Teses / dissertações: "Brood parasitism"

1

Nair, Radha Goh. "Neural adaptations for brood parasitism". Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409117.

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2

Gloag, Rosalyn Suzanne. "Brood parasitism by shiny cowbirds". Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:b9a9d900-ed14-4bb0-8979-7fd782584f00.

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Brood parasitic birds lay eggs amongst the clutches of other species, which then assume all costs of parental care on their behalf. This thesis addresses several puzzles of avian brood parasitism, using field studies and theoretical modelling of the generalist parasite, the shiny cowbird (Molothrus bonariensis) and select hosts in Argentina. Key findings and conclusions were: • High parasitism intensity in a host population can result in a cost to hosts of removing parasite eggs from their clutches, and so help to maintain host’s acceptance of parasite eggs in evolutionary equilibrium. The cost is to host egg survival: hosts that remove parasite eggs from the clutch increase the risk that their eggs are destroyed by subsequent parasites that visit the nest. • The principal benefit of mobbing as a front-line defence of hosts may be to reduce egg loss due to parasite attack, rather than prevent parasitism itself. • Differences in the acoustic structure of begging calls between parasites and their host’s young can be to the parasite’s advantage. Parents provisioned unparasitized broods more during broadcast at the nest of shiny cowbird calls than calls of their own species’ chicks, in both a common host and a non-host. The long tremulous quality of a cowbird’s call functions analogously to a rapid call rate, thereby exploiting a common provisioning rule of avian parents. • A trade-off for maximum growth in parasite nestlings will variously favour or not favour the evolution of nestmate-killing behaviour, depending on a parasite’s abilities, relative to host young, to solicit and attain provisions from host parents. Generalist parasites can encounter both sides of the trade-off in different hosts. Meanwhile, indirect fitness costs are unlikely to constrain the evolution of nestmate-killing in shiny cowbirds, as they rarely, if ever, share the nest with siblings.

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3

Reichart, Letitia Marie. "Conspecific brood parasitism in ruddy ducks (Oxyura jamaicensis)". Online access for everyone, 2008. http://www.dissertations.wsu.edu/Dissertations/Summer2008/L_Reichart_072408.pdf.

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4

Lindholm, Anna Kristina. "Evolution of host defences against avian brood parasitism". Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627230.

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5

Harrison, Martin D. "Using game theory to model interspecific brood parasitism in bird populations". Thesis, University of Sussex, 2010. http://sro.sussex.ac.uk/id/eprint/6290/.

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The interaction between hosts and parasites in bird populations has been studied extensively. I use game theoretic methods to model this interaction. This has been done previously but has not been studied taking into account the detailed sequential nature of this game. I introduce models allowing the host and parasite to make a number of decisions which will depend on a number of natural factors. A sequence of events follows, which is broken down into two key stages; firstly the interaction between the host and the parasite adult, and secondly that between the host and the parasite chick. The final decision involves the host choosing whether to raise or abandon the chicks that are in the nest. There are certain natural parameters and probabilities which are central to these various decisions; in particular the host is generally uncertain whether parasitism has taken place, but can assess the likelihood of parasitism based upon certain cues (e.g. how many eggs remain in its nest). I have taken elements of games which have been previously created and constructed my own models to fully describe this interaction. These parasites have different methods of parasitizing the nests of their hosts, and the hosts can in turn have different reactions to these parasites. This is later built into a model where there is more than one host nesting over a breeding season. We have a number of nesting sites and different time points in which the host can begin to nest. In the previous models the host was given the opportunity to abandon the nest. In this game the host is allowed to abandon and then restart the nesting process. The probability that the host is parasitized can be decided using a number of factors including the number of hosts laying during a given time period, the nesting site or the number of parasites during the course of the season. Using these models we are able to find situations which match those which we have seen in nature. Also the models are able to predict what natural changes such as parasitism rate or mimicry will do to the interaction. Overall I believe these models to give as good an indication of the key elements of the interaction and how they can change over time.

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6

Porneluzi, Paul A. "Effects of forest fragmentation on the biology of the Ovenbird /". free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9821351.

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7

McRae, Susan Barbara. "An ecological and genetic analysis of breeding strategies in the moorhen, Gallinula chloropus". Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309703.

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8

Groulx, Adam. "Nesting aggregation as a Determinant of Brood Parasitism in Mason Bees (Osmia spp.)". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34322.

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Identifying forces that affect population dynamics can allow us to better understand the distribution and abundance of animals. Both top-down and bottom-up factors can significantly influence animal populations. Mason bees (members of the genus Osmia; Hymenoptera: Megachilidae) are important pollinators for agricultural systems and are vulnerable to exploitation by brood parasites, such as kleptoparasitic wasps. High levels of nesting density have the potential to increase rates of brood parasitism by attracting larger numbers of parasites to areas with aggregations of nests. I conducted a field study in subalpine meadows at the Rocky Mountain Biological Laboratory in Colorado, USA, to assess whether mason bees suffer increased brood parasitism as the size of nesting aggregations increases. Mason bees were allowed to nest in artificial nest boxes and establish natural variations in numbers of nesting individuals within nest boxes. Nest cells constructed by bees were then checked for the presence of kleptoparasite larvae shortly after they were completed. Overall, nest cells constructed in blocks containing multiple active bees were significantly more likely to be oviposited in by brood parasites compared to cells constructed in blocks with fewer active nesting bees. This suggests that gathering in large aggregations for nesting can negatively affect populations of mason bees, given the high levels of brood parasitism observed in areas of high nesting density. In addition, the last nest cell in mason bee nests was significantly more likely to be parasitized than inner cells, suggesting bees may be abandoning nests that are parasitized, representing a potential defensive response of bees to brood parasitism. These results have implications for the management of mason bees as agricultural pollinators, as cultivating them in large groups could reduce their survival.

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9

Hughes, Janice Maryan. "Systematics of New World cuckoos (Aves, Cuculidae) and the evolution of brood parasitism". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0019/NQ27664.pdf.

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10

Fernando, Raniero. "Brood parasitism and genetic parentage in Goldeneye ducks, an analysis using DNA fingerprinting". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0027/MQ51602.pdf.

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11

Janishevski, Lisa. "Nest parasitism in red-breasted mergansers (Mergus serrator) in New Brunswick". Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31244.

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Intraspecific nest parasitism was studied in a group of colonial Red-breasted Mergansers (Mergus serrator) nesting on the Tern Islands of Kouchibouguac National Park in New Brunswick in 1992. Nest parasitism is very common in this colony, and may influence the high rate of nest abandonment observed. Emphasis was placed on determining rates of successful parasitism (i.e. eggs added during the laying period of the hen at that nest), which are evolutionarily significant, and can easily go undetected. Three methods were used to determine if a nest contained egg(s) from another hen: abnormally large clutch size: more than one egg laid per day: and comparisons of DNA fingerprints of the hen versus putative chicks. When eggs were added to a nest during incubation, the nest was also labelled parasitized, but such eggs were not fully incubated (non-term) and thus were not successful. A new method of blood sampling ducklings in pipped eggs was tested and found to have negative effects on survival. As many as 14.8% (13/88) of the ducklings sampled subsequently died. Researchers wishing to use this method should proceed with caution. DNA fingerprinting determined that 50.0% of nests tested (6/12) were successfully parasitized. Two of six parasitized nests would have gone undetected using the other criteria to detect parasitism, thus proving the value of DNA fingerprinting. Of hatched young genetically analyzed, 30.9% (17/55) were parasitic. Nest parasitism appears to be an alternative breeding strategy in this population. Extra-pair copulation, previously unrecorded in this species, was discovered through DNA fingerprinting in two of four nests analyzed.

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12

Tucker, Anna. "The occurrence and consequences of conspecific brood parasitism in the Prothonotary Warbler (Protonotaria citrea)". VCU Scholars Compass, 2014. http://scholarscompass.vcu.edu/etd/3450.

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Brood parasites avoid costs associated with raising young by adding eggs to another individual’s clutch and providing no parental care. When conspecific brood parasitism occurs in species with high parental investment, we expect hosts to suffer costs for raising an enlarged brood. Here I describe conspecific brood parasitism (CBP) in the prothonotary warbler using maternal exclusion analyses of 333 family groups. I found that 23.4% of clutches contained at least one offspring that was not matched to the social mother and determined that parasitism seems to be an opportunistic tactic. Hosts had lower average annual reproductive success than non-hosts, but CBP did not affect adult survival or nestling body condition and likelihood of recruitment. Clutches with CBP received less provisioning from the male, but not female, parent. Future research is needed to understand the effects of density and competition on the breeding behaviors of this and other similar species.

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13

Dugger, Bruce D. "The impact of brood parasitism on host fitness in common pochards and tufted ducks /". free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9809678.

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14

Burhans, Dirk E. "Anti-brood parasite defenses and nest-site selection by forest-edge songbirds in Central Missouri /". free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9712795.

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15

Shizuka, Daizaburo. "Parental strategies and family life of American Coots: brood parasitism, sibling rivalry, and life history /". Diss., Digital Dissertations Database. Restricted to UC campuses, 2009. http://uclibs.org/PID/11984.

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16

Kozlovic, Daniel Raymond. "Consequences of brood parasitism by cowbirds on house finches in a new area of sympatry". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0013/NQ27981.pdf.

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17

Begum, Sajeda. "Brood Parasitism in Asian Cuckoos: Different Aspects of Interactions between Cuckoos and their Hosts in Bangladesh". Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for biologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14913.

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The interaction between brood parasitic cuckoos and their hosts represents a traditional example of coevolution, whereby obligate interspecific brood parasitic cuckoos completely rely on their hosts to do their parental care for them by laying their eggs in the host’s nest. This thesis brings together a great deal of information documenting and clarifying the interactions between different species of hosts and their respective parasitic cuckoos in Bangladesh. I recorded parasitism rates to determine the extent of brood parasitism and to identify the host species that were parasitised by sympatric cuckoos. Four parasitic cuckoos were documented: the Asian koel ( Eudynamys scolopacea), the common hawk cuckoo (Cuculus varius; previously known as Hierococcyx varius), the pied cuckoo (Clamator jacobinus) and the Indian cuckoo (Cuculus micropterus). These cuckoos were sympatric and parasitised different host species, including the house crow (Corvus splendens), the long-tailed shrike (Lanius schach), the common myna (Acridotheres tristis), the jungle babbler (Turdoides striatus) and the black drongo (Dicrurus macrocercus). All of these cuckoo species are obligate brood parasites. The Asian koel utilised the following three hosts: the house crow, the common myna and the long-tailed shrike. The latter was recorded for the first time as a host for the Asian koel in Bangladesh. We found that koel eggs were highly non-mimetic to those of common myna and long-tailed shrike, but showed good mimicry to house crow eggs. Indian cuckoos showed excellent egg mimicry with the eggs of their black drongo hosts, as did common hawk cuckoos and pied cuckoos with their jungle babbler host. The hosts accepted the eggs of all four cuckoo species. However, the common myna was more likely to abandon nests parasitised by the koel than unparasitised ones. All of the host species suffered the costs of koel parasitism, showing reduced breeding success. Proximity to fruit trees was an important predictor of the probability of parasitism in the three koel host species studied. There was a significant positive relationship between nest volume and probability of parasitism by Asian koels. Furthermore, the colonial breeding house crows suffered comparatively less parasitism than the other two koel host species. Long-tailed shrike nests close to conspecific neighbours were less likely to be parasitised, and the risk of parasitism was increased in nests lower to the ground. The risk of parasitism increased during the breeding season for house crows and common mynas. All three Asian koel hosts tolerated multiple parasitism. We investigated whether there was any interspecific competition among the sympatric cuckoos. In theory, sympatric parasites should show niche segregation through variation in host use. As predicted, each cuckoo species parasitised different host species; however, host use overlapped in common hawk cuckoos and pied cuckoos, but interspecific competition was reduced because these two cuckoo species have different breeding seasons. Furthermore, there was a significant difference in parasitism rate among the three main habitats: human habitations, mixed scrub forests and monoculture plantations. This indicated that different cuckoos favour specific habitats, even if their favourite host also occurs elsewhere. Finally, I tested responses against foreign eggs by the cuckoo hosts as well as by potential cuckoo hosts in the study area. For this purpose, I used differently sized and coloured model eggs. Common mynas and jungle babblers accepted all non-mimetic eggs, as did most of the house crows (91 %). Long-tailed shrikes rejected 75 % of the non-mimetic model eggs. Finally, black drongos turned out to be strong rejectors and could do so without damaging any of their own eggs, most likely because they grasped and ejected the non-mimetic model egg. This result indicates that the black drongo has been in a coevolutionary arms race with the Indian cuckoo since drongos accepted mimetic cuckoo eggs. Species such as the Oriental magpie robin (Copsychus saularis), red-vented bulbul (Pycnonotus cafer) and Asian pied starling (Gracupica contra), which likely have no history of interaction with cuckoos, accepted 100 % of the non-mimetic model eggs. In conclusion, our findings describe host nest use cues used by the Asian koel, which may provide background for further studies in other sympatric brood parasites. In spite of the high degree of acceptance of parasitic eggs, the breeding success of both cuckoos and hosts should be more closely studied to obtain a better understanding of the costs of parasitism. Future experimental studies are highly recommended to achieve a better understanding of host responses to Asian cuckoo species.

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18

Eadie, John McAllister. "Alternative reproductive tactics in a precocial bird : the ecology and evolution of brood parasitism in goldeneyes". Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29092.

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Facultative brood parasitism is common among waterfowl (Anatidae), but we have limited understanding of the ecological or evolutionary basis for this behaviour. I studied facultative brood parasitism in two species of cavity-nesting ducks, the Barrow's goldeneye (Bucephala islandica) and the common goldeneye (B. clangula). During a four year study in central British Columbia, I used field experiments, observational studies of marked individuals, and simulation models to (i) examine the consequences of brood parasitism to hosts, and (ii) identify the factors that promote and maintain parasitic behaviour. In order to assess the costs and benefits of brood parasitic behaviour, I first examined proximate influences on reproductive performance of goldeneye females. Variance in reproductive success among females was substantial and some females were consistently more successful than others. Reproductive success was also influenced by breeding experience, time of breeding, and by the availability and quality of nest-sites. Circumstantial evidence suggests that females compete exploitatively and aggressively for nest-sites and brood territories. I argue that such conditions favour the evolution of parasitic reproductive behaviours. Parasitic egg-laying occurred frequently during the four years of this study; 35% of all nests were parasitized, while 17% of all eggs were parasitic. Parasitism had few deleterious effects on the reproductive success of hosts. On average, parasitized females produced as many of their own young as non-parasitized females, and there was no effect of parasitism on female survival or on the growth and survival of host young. Hatch success was reduced in some host nests when the frequency of parasitism was high, but such levels of parasitism were uncommon. These results suggest that the costs of brood parasitism to precocial hosts are low. My findings do not support recent speculations that hosts benefit from being parasitized. Goldeneye females exhibited few defences against parasitic intrusions. Females were more likely to desert their nests when clutch sizes were extreme (i.e., > 16 eggs), but desertion rates did not differ significantly between parasitized and non-parasitized nests. I found no evidence that hosts reduce the size of their own clutch when parasitized, contrary to Anders son & Eriksson's (1982) findings for common goldeneyes in Sweden. On some occasions, hosts removed eggs from their nests, but this appeared to be a response to damaged eggs, rather than a defence against parasitism. Finally, females with territories adjacent to their nest sites were parasitized as often as females with non-adjacent territories, indicating that site-specific territoriality in goldeneyes does not serve to guard nests from parasites. I tested three hypotheses that have been proposed to explain parasitic behaviour. Brood parasites did not attempt to incubate clutches to which they had contributed, even when host females were experimentally removed from those nests. I therefore reject the hypothesis that brood parasitism is an inadvertent consequence of contests among females for the same nest site. In contrast, parasitic behaviour was more frequent in young females, and was strongly related to the availability of nest-sites. These results support the hypothesis that parasitic laying is a conditional strategy pursued by young females when nest-sites are limited. However, other evidence was consistent with the hypothesis that 'parasitic' and 'parental' behaviours are alternative tactics in a mixed strategy. Estimated lifetime reproductive success was nearly identical for the two groups of females, and the relative reproductive success of parasites was negatively frequency-dependent. A simulation model incorporating the effects of both density-dependence and frequency-dependence resolved this paradox. The model revealed a density threshold below which frequency-dependence effects were negligible, but above which frequency-dependence played a prominent role. I show that results consistent with both hypotheses are possible when the effects of population density are included. Current theories for the evolution of alternative reproductive tactics focus primarily on the frequency-dependent components of fitness and ignore the effects of population density. My results indicate that density-dependence and frequency-dependence can interact in an unanticipated way to maintain alternative nesting tactics in goldeneyes.
Science, Faculty of
Zoology, Department of
Graduate

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19

Bouchard, M'Liki Jovette. "Determining rates of intraspecific nest parasitism in a colony of Red-breasted Mergansers (Mergus serrator) using microsatellite analysis". Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32764.

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The rate of intraspecific nest parasitism was determined for a colony of Red-breasted Mergansers (Mergus serrator) nesting on the Tern Islands in Kouchibouguac National Park, New Brunswick. In order to recognize instances of nest parasitism, field criteria and microsatellite analysis testing for parentage between attending hens and the eggs in their nests were used. Traditionally, molecular analysis has involved collecting blood samples from females and offspring, however, for the purpose of this study, DNA was extracted successfully from feathers, egg membranes, and unhatched embryos which were collected during the summers of 1999 and 2000. A total of 8 primer pairs which amplified microsatellite loci in closely related avian species were tested (Sfimu-2, Sfimu-3, Sfimu-4, Sfimu-5, Sfimu-6, Sfimu-7, Bcamu-6, and Alamu-1). Four of these primers produced product of the expected size (Sfimu-3, Sfimu-4, Sfimu-7, and Bcamu-6). Amplification of these loci, however was inconsistent and subsequent sequence analysis revealed that the amplicons did not contain tandem repeats and therefore were not useful in genotyping. From field criteria we were able to establish rates of parasitism of 46% and 44% for each season. Rates of parasitism tended to be higher at the beginning of the season, compared to nests initiated later. Field criteria bring support to several hypotheses on causes of nest parasitism, indicating that more than one may influence rates of parasitism in a population.

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20

Burgham, Mark Colin John. "The impact of brood parasitism by the brown-headed cowbird on the reproductive tactics of the yellow warbler". Thesis, University of Ottawa (Canada), 1985. http://hdl.handle.net/10393/5043.

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21

Jensen, William Eric. "Spatial variation in brown-headed cowbird (Molothrus ater) abundance and brood parasitism in the Flint Hills tallgrass prairie /". Search for this dissertation online, 2003. http://wwwlib.umi.com/cr/ksu/main.

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22

Rasmussen, Justin Lee. "Investigations of evolutionary arms races and host diversity in avian brood parasite systems". Thesis, University of Canterbury. Biological Sciences, 2013. http://hdl.handle.net/10092/8959.

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Obligate brood parasites rely solely on other species, the hosts, to incubate their eggs and raise their offspring, which often reduces the host’s reproductive output. This reproductive cost has led to the evolution of anti-parasite adaptations among hosts, which in turn, has led to better trickery by parasites, a process termed an evolutionary arms race. The objective of this thesis was to investigate host-parasite coevolutionary arms races to address questions of host-use diversity. Host diversity varies dramatically among brood-parasitic species, but reasons for variations in host-use among brood parasites are not well understood. In Chapter 2, I address questions on host diversity specifically, whereas I address questions about coevolutionary interaction between hosts and parasites in Chapters 3, 4 and 5 using two host-parasite systems, one in New Zealand and one in North America. Chapter 2 investigates if host diversity is constrained by aggressive nest defence behaviour. I compared the nest defence behaviour of the exclusive host of the shining cuckoo Chrysococcyx lucidus lucidus on the main islands of New Zealand, the grey warbler Gerygone igata, to two other potentially suitable hosts that are not currently parasitised, the fantail Rhipidura fuliginosa and the silvereye Zosterops lateralis. The results suggest that grey warblers are as aggressive as fantails and silvereyes towards shining cuckoos at the nest and thus, host specialisation in shining cuckoos in New Zealand, at least, does not appear to be the result of nest-defence constraints imposed by potential but unused host species. Chapter 3 investigates if red-winged blackbirds Agelaius phoeniceus, a species that typically accepts the eggs of parasites, recognises, as indicated by changes in incubation behaviour, when they have been parasitised by brown-headed cowbirds Molothrus ater. Recognition without rejection suggests that rejection may be context-dependent but the results suggest that red-winged blackbirds do not recognise when their nests have been parasitised by brown-headed cowbirds, at least at the egg stage. This study was the first to investigate if hosts that almost invariably accept the eggs of parasites recognise when they have been parasitised. Chapter 4 investigated the possibility of coevolutionary arms races occurring through olfactory channels in contrast to earlier work that focussed only on visual and auditory cues. Recent research has revealed that olfactory abilities in birds are more common than previously thought. Uropygial gland secretions are posited to be a key source of avian body odour and its composition has been found to vary among species and individuals as well as between the sexes. I compared gas-chromatography (GC-FID) traces of shining cuckoo preen wax to the GC-FID traces of the grey warbler, the only host of the shining cuckoo in mainland New Zealand, as well as the preen wax of seven other species for evidence of mimicry. Preliminary results suggest there is evidence for mimicry and the potential for odour-based nestling discrimination in grey warblers. Further tests recording the response of grey warblers to odour-manipulated nestlings are necessary. Finally, in Chapter 5, I investigated the response of the song thrush Turdus philomelos, a species that rejects the eggs of the common cuckoo Cuculus canorus and conspecifics at intermediate and low frequencies, respectively, to nest-odour manipulations using the preen wax of conspecifics and heterospecifics. The results suggest song thrush do not use odour to assess the risk of parasitism at least as indicated in terms of changes in incubation behaviour. Investigations of the role of olfaction in avian brood parasite systems can provide a better understanding of brood-parasite coevolution. Only by considering all channels of communication can we be sure to completely understand the coevolutionary dynamics between brood parasites and their hosts.

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23

Tate, Douglas Patrick. "Occurrence patterns of the brown-headed cowbird, Molothrus ater, and rates of brood parasitism in island vs. mainland habitats". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ33280.pdf.

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24

Anderson, Michael Gareth. "Evolutionary interactions of brood parasites and their hosts : recognition, communication and breeding biology : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, Auckland, New Zealand". Massey University, 2009. http://hdl.handle.net/10179/1167.

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Obligate brood parasites lay their eggs in nests of other species, relying on these host parents to care for their offspring. This phenomenon has been a curiosity amongst researchers since its first description and has become a model study system for testing such ideas as coevolution and species recognition. This thesis examines a few of the many questions that arise from this breeding system. The New Zealand Grey Warbler (Gerygone igata) and its brood parasite, the Shining Cuckoo (Chrysococcyx lucidus) are used as the main study species, although research on the eviction behaviour of Common Cuckoos (Cuculus canorus) has also been conducted. First, the current state of knowledge and recent discoveries regarding nestling rejection abilities of hosts is reviewed in chapter one. Second, a comparative study of New Zealand passerine begging calls has been conducted to test for begging call similarity between a brood parasite and its host, as well as developing a new technique for detecting the mode of coevolution that may be occurring in the parasite – host relationship. Parent-offspring communication in Grey Warblers is also examined to test for both parental and nestlings Parents use both alarm calls to warn offspring of potential danger, and also parental feeding calls to elicit a begging response from nestlings. By contrast, nestlings are able to signal both age and short term levels of need to parents through the acoustic structure of the begging call. The evolutionary costs and benefits of egg eviction behaviour in the Common Cuckoo are also tested. An experimental approach showed that egg eviction had a growth cost, but this cost was temporary and restricted to during and immediately after the egg eviction phase. A pattern of compensatory growth was observed after the eviction period, so that during the later nestling stages there was no difference in mass, and no difference in fledging age. Finally, variation in the Grey Warbler breeding biology and Shining Cuckoo parasitism rates are examined through both time and across latitudes. This research has shown a counterintuitive pattern of breeding phenology across latitudes. These patterns have implications for Shining Cuckoos both in terms of timing of available nests and host selection. Keywords: Begging call, breeding phenology, brood parasitism, coevolution, Common Cuckoo, eviction, Grey Warbler, parent-offspring communication, Shining Cuckoo.

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25

Kosciuch, Karl L. "Host-parasite interactions on an experimental landscape". Diss., Manhattan, Kan. : Kansas State University, 2006. http://hdl.handle.net/2097/186.

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26

Tolvanen, J. (Jere). "Informed habitat choice in the heterogeneous world: ecological implications and evolutionary potential". Doctoral thesis, Oulun yliopisto, 2018. http://urn.fi/urn:isbn:9789526218939.

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Abstract Animals live in a heterogeneous world where threats and abundance and quality of resources vary across space and time. Heterogeneity induces uncertainty in decisions that animals must make, e.g., where to breed. Adaptive decisions may be facilitated by personally collecting information on the quality of the environment and by observing the behaviour and success of other individuals. Such social information use is common in nature. I investigate information use in relation to ecological threats (brood parasites, nest predators) and long-term information use in breeding site choice in the wild. Moreover, I examine the genetic basis of social cue use in breeding site choice. I demonstrated experimentally that open-nesting hosts of a brood parasite, the common cuckoo (Cuculus canorus), can cue on cuckoo vocalizations to estimate cuckoo abundance and avoid breeding sites with high perceived parasitism risk. Another experiment showed that pied flycatchers (Ficedula hypoleuca) derive predation risk information from the fates of heterospecific nests, can associate the information with a nest site characteristic and generalize the association to own nest site choice. However, apparently only young females that made their choice quickly used the information in nest site choice. Pied flycatchers were further observed to collect habitat quality information based on the old nest contents during the post-breeding period. Use of the information in breeding site choice in the following spring varied between sex and age groups as well as geographically. Some birds integrated the post-breeding period information with the information available during settlement suggesting sequential social information use. Finally, quantitative genetic analyses revealed low additive genetic variances and genetic heritabilities of social cue use in breeding site choice in a collared flycatcher (Ficedula albicollis) population. These results demonstrate new aspects of informed habitat choice in wild animals which have important implications for species coexistence and community ecology, parasite-host coevolution, between-species niche dynamics and evolution. Between-individual variation in information use is highlighted throughout the thesis and warrants further research. The evolutionary potential of information use appears low, but more studies in other populations and species are needed
Tiivistelmä Eläimet elävät ympäristössä, jossa resurssit ja uhat vaihtelevat ajallisesti ja alueellisesti. Tämä vaihtelu aiheuttaa epävarmuutta eläinten päätöksentekoon, kuten pesimäpaikan valintaan. Hyödyllisten päätösten tekoa voi edesauttaa keräämällä tietoa ympäristön laadusta itsenäisesti tai seuraamalla muiden yksilöiden käytöstä ja menestystä. Tällainen sosiaalisen informaation käyttö on yleistä eläinkunnassa. Tutkin informaation käyttöä ekologisten uhkien (pesäloiset, -pedot) suhteen ja pitkäaikaista informaation käyttöä pesimäpaikan valinnassa luonnonpopulaatioissa. Lisäksi selvitän pesimäpaikan valintaan liittyvän informaation käyton geneettistä periytyvyyttä. Selvitin kokeellisesti, että pesäloisen, käen (Cuculus canorus), isäntälajit voivat käyttää käkien ääntelyä vihjeenä alueellisesta loisintauhasta ja siten välttää korkean uhan alueita pesimäpaikan valinnassa. Toisessa kokeessa havaittiin kirjosieppojen (Ficedula hypoleuca) keräävän tietoa pesäpetouhasta toisen lajin pesätuhojen kautta, kykenevän yhdistämään tiedon erilliseen pesäpaikan ominaisuuteen ja käyttämään tätä assosiaatiota omassa pesäpaikan valinnassa. Kuitenkin vain nuoret naaraat, jotka tekivät valintansa nopeasti, käyttivät kyseistä informaatiota valinnassaan. Lisäksi havaitsin kirjosieppojen keräävän tietoa ympäristön laadusta pesinnän jälkeen vanhojen pesäsisältöjen avulla. Kyseisen tiedon käyttö pesimäpaikan valinnassa seuraavana keväänä vaihteli lintujen sukupuolen ja iän suhteen, kuin myös alueellisesti. Osa linnuista yhdisti pesimäpaikan valinnassaan aikaisempaa, pesinnän jälkeen kerättyä tietoa ja keväällä saatavilla olevaa sosiaalista informaatiota. Geneettinen analyysi viittasi pesimäpaikan valintaan liittyvän informaation käytön alhaiseen additiivisen geneettisen varianssin määrään ja siten alhaiseen geneettiseen periytyvyyteen sepelsiepolla (Ficedula albicollis). Väitöskirjani tulokset kuvaavat uudenlaisia informaation käytön muotoja eläinten pesimäpaikan valinnassa. Havainnot auttavat ymmärtämään pesälois-isäntä rinnakkaisevoluutiota, lajien välisiä vuorovaikutuksia, lajiyhteisöjen toimintaa ja evoluutiota. Yksilöiden välinen vaihtelu informaation käytössä näyttää olevan yleistä, ja lisätutkimuksen tarpeessa. Informaation käytön evolutiivinen potentiaali näyttää rajalliselta, mutta lisätutkimukset eri populaatioilla ja lajeilla ovat tarpeen

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27

Mcclean, Luke Alexander. "Coevolution between brood-parasitic honeyguides and their hosts". Doctoral thesis, Faculty of Science, 2021. http://hdl.handle.net/11427/32856.

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Obligate brood parasites lay their eggs in the nests of other species, foisting the costs of parental care onto the host parents. The success of the parasite and host are then at odds, with both parties evolving defences and countermeasures in an evolutionary arms race. This reciprocal influence of acting upon both species' evolution — a process known as coevolution — has forged the natural world around us. Avian brood parasites and their hosts are now model systems for studying such coevolutionary interactions between species, providing striking examples of the adaptations that arise when the life histories of two species become entangled. In this thesis I highlight the adaptations that have arisen in response to coevolutionary selection pressures in a group of understudied avian brood parasites, the honeyguides (Indicatoridae), and their hosts. This study focuses on the greater (Indicator indicator) and lesser (I. minor) honeyguides, and their respective primary hosts, the little bee-eater (Merops pusillus) and the black-collared barbet (Lybius torquatus). The interactions between honeyguides and their cavity-nesting hosts of the Old World tropics are evolutionarily ancient, contrasting with the majority of studies of avian brood parasitism which have predominantly focused on temperate brood-parasitic species targeting open cup-nesting hosts. Therefore, honeyguides and their hosts are an ideal study system in which look for novel adaptations that have not evolved in other systems. Using field observations and experimental manipulations at each stage of the parasitic life cycle — before parasitism, during egg-laying, during incubation, and during chickrearing — I examine how honeyguides and their hosts have evolved in response to the selection pressures they exert on each other. First, in chapter two, I consider whether the nest structure of the little bee-eater – host to the greater honeyguide – can act as a defence against brood parasitism. Experimental manipulation of the size of bee-eater nest tunnels demonstrates that bee-eaters with narrower nest tunnels are less likely to be parasitized by greater honeyguides than those bee-eaters whose nests have wider nest tunnel entrances. This study provides the first experimental evidence of a host nest functioning as a frontline defence against brood parasitism. In chapter three, I take a comparative approach and use a phylogenetic framework to investigate, across multiple avian brood parasite species, the evolutionary drivers of rapid egglaying. This trait is shared by most brood-parasitic birds, but not by non-parasitic birds. I find strong evidence that the egg-laying speed of avian brood parasites is ecologically and physiologically constrained, but find no evidence that variation in the costs incurred duringparasitism events have driven variation in the rapidity of egg-laying among brood-parasitic species. In chapter four, I examine whether there are costs associated with the virulent egg puncturing behaviour of greater honeyguides, and whether honeyguides can adjust their level of virulence in accordance with these costs. I find strong support for the idea that virulence is costly to honeyguides, as bee-eater hosts are more likely to reject clutches that contained eggs punctured by honeyguides. Such punctured clutches are also more likely to be predated. Honeyguides appear to adjust how much they puncture host eggs in accordance with the severity of these costs, providing the first evidence of an avian brood parasite moderating its virulence in response to the associated costs. In chapter five, I examine egg rejection behaviour in the black-collared barbet, a common host of the lesser honeyguide. I consider whether the (smaller) size of a parasitic egg could be used as a cue for egg rejection inside the dark environment of a cavity nest. Through observations of natural parasitism events, and experimental parasitism of host nests using different sized eggs, I demonstrate that barbets are more likely to reject a clutch of eggs when they detect a small egg within the nest. This seems to be achieved through a process of true recognition, a mechanism that involves a specific innate or learnt template of what size eggs a host should reject. Barbets do not appear to rely on discordancy – comparing all eggs within their clutch in order to reject the odd one out – in order to make rejection decisions. Finally, in chapter six I explore whether honeyguides elicit additional provisioning from their foster parents by using vocal mimicry, and investigate why such extra food would be required. I demonstrate that both greater and lesser honeyguides mimic the sound of a brood of chicks of their respective hosts in order to receive higher levels of provisioning from their foster parents. I establish that greater and lesser honeyguides do this for contrasting reasons. Greater honeyguides require higher levels of provisioning to support their fast growth rate to a size much larger than their host siblings, whereas lesser honeyguides require more food in order to offset a sub-optimal diet provided to them by their foster parents.

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28

Stokke, Bård Gunnar. "Coevolutionary adaptations in avian brood parasites and their hosts". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Natural Sciences and Technology, 2001. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-161.

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Dette prosjektet har satt søkelyset på to problemstillinger knyttet til samevolusjonen mellom parasitt og vert; 1) utvikling av vertstilpasninger som mottrekk mot tilpasninger hos parasitten, med spesiell fokus på eggtilpasninger, og 2) mekanismer som kan forklare den store variasjonen i forsvarsatferd mot kullparasittisme blant ulike verter.

1) Flere gjøk- (Cuculus canorus) stammer eller gentes har utviklet egg som er veldig like vertens egne egg, såkalt eggmimikry, for å vanskeliggjøre vertenes eggavvisning. For å svare på dette har mange verter på sin side gjort det vanskeligere for parasitten ved å utvikle en lavere variasjon i utseende mellom sine egg innen kullet (innenkull-variasjon), og en høyere variasjon mellom egg fra kull til kull (mellomkull-variasjon). Mange nordamerikanske spurvefugler blir benyttet som verter av brunhodetrupialen (Molothrus ater), men denne parasitten har ikke utviklet eggmimikry i forhold til vertseggene. Vi sammenlignet kullvariasjonen mellom spurvefugler i Europa og Nord-Amerika og fant en høyere innenkull-variasjon og en lavere mellomkull-variasjon i eggutseende hos nordamerikanske spurvefugler, selv om forskjellen i innenkull-variasjon mellom kontinentene var mindre enn forventet.Hos europeiske spurvefugler er det i tidligere eksperimenter funnet at det er en sammenheng som forventet mellom avvisningsraten overfor parasittiske ikkemimikry egg og kullvariasjonen i eggutseende. Vi fant at det ikke var noen slik sammenheng hos spurvefugler i Nord-Amerika. Resultatene gir støtte til hypotesen om at parasitter med eggmimikry utøver et betydelig seleksjonstrykk for utvikling av bestemte eggkarakterer hos sine verter.

Vi undersøkte om det var noen forskjell i innenkull-variasjon hos avvisere og akseptorer av parasittegg innen bestemte populasjoner av tre europeiske spurvefugler; rørsanger (Acrocephalus scirpaceus), bokfink (Fringilla coelebs) og munk (Sylvia atricapilla). Det ble funnet at det var en signifikant forskjell i innenkull-variasjon i eggutseende mellom avvisere og akseptorer av kunstige ikke-mimikry gjøkegg i en rørsanger-populasjon i Tsjekkia; avviserne hadde en lavere innenkull variasjon enn akseptorer av slike egg. Denne vertspopulasjonen har en intermediær avvisningsrate overfor ikke-mimikry egg. Et tilsvarende forsøk ble utført hos en bokfink-populasjon i Norge og en munk-populasjon i Tsjekkia. Begge artene er meget gode avvisere av ikke-mimikry egg, noe som indikerer at de aller fleste individer er i stand til å avvise slike egg. Vi valgte derfor å benytte egg fra artsfrender i forsøkene med disse artene. I motsetning til hos rørsangeren fant vi at det ikke var noen forskjell i innenkullvariasjon mellom akseptorer og avvisere av fremmede egg hos bokfink og munk. Hos begge artene ble det funnet at avvisningen av fremmede egg i stor grad avhenger av kontrasten (grad av mimikry) mellom egne egg og parasittegget. Dette viser at selv om individene er i stand til å avvise parasittegg, så finnes det kognitive begrensninger som medfører at egg som utseendemessig ligger under en viss terskelverdi med hensyn til likhet med egne egg vil bli akseptert. Det ble ikke funnet noen indikasjoner på at avvisningsatferden var avhengig av vertenes alder eller av kondisjonelle stimuli for noen av de tre artene. Dette kan tyde på at det er en genetisk basert kobling mellom det å kunne gjenkjenne fremmede egg og innenkull-variasjon.

2) Mange vertsarter viser ingen eller kun intermediære avvisningsrater overfor fremmede ikke-mimikry egg. En slik tilsynelatende suboptimal atferd kan skyldes at det er kostnader forbundet med avvisningen som forhindrer evolusjon av perfekt avvisningsatferd. Slike kostnader kan være feilaktig avvisning av egne egg i uparasitterte reir (gjenkjenningsfeil), eller avvisning av egne egg i tillegg til parasittegget i parasitterte reir (avvisningskostnader). Hos gjøkverter, som ved suksessfull gjøkparasittisme har en reproduktiv suksess tilnærmet lik null, vil kun gjenkjenningsfeil være kilde til et potensielt seleksjonstrykk mot utvikling av høy avvisning av fremmede egg. Vi undersøkte om slike kostnader forekommer hos bokfink og munk; to arter som antas å ha blitt benyttet av gjøken tidligere, men som i dag ikke blir regelmessig parasittert. På grunn av at avvisningsatferden opprettholdes i fravær av parasittisme, forventet vi at disse artene begår få gjenkjenningsfeil.

Undersøkelsen gav støtte til denne prediksjonen; avvisningskostnader i parasitterte reir var relativt høye, men gjenkjenningsfeil i uparasitterte reir var meget sjeldent forekommende.

En hypotese ("spatiell habitat-struktur hypotesen") basert på metapopulasjonsdynamikk og med vekt på karakteristikker vedrørende vertsartenes hekkebiotop ble framsatt for å forklare de store variasjonene i avvisning hos europeiske spurvefugler. Hypotesen bygger på at gjøken benytter de verter som hekker nær utkikkspunkter for parasitten, dvs. nær trær. Arter som hekker både nær og langt fra trær er de beste gjøkvertene, i og med at genflyt fra uparasitterte populasjoner vil forhindre utvikling av perfekt avvisning i parasitterte populasjoner. Arter som alltid hekker nær trær har høye avvisningsrater fordi få eller ingen populasjoner har unnsluppet parasittering, og det har derfor vært sterk seleksjon for utvikling av vertsforsvar. Data for gjøkverter i Europa gav god støtte til hypotesen. Grad av parasitt eggmimikry og parasitteringsrater er høyest hos de vertsarter som kan hekke både langt fra trær og nær trær, noe som tyder på at gjøken har størst suksess hos slike arter.

This thesis deals with two topics in the coevolution between brood parasites and their hosts: 1) evolution of host adaptations against parasite egg mimicry, and 2) sources that could explain the considerable variation in rejection behaviour found among various passerines.

1) Several common cuckoo (Cuculus canorus) tribes or gentes in Europe have evolved eggs that are remarkably similar to the host eggs in both size and appearance (i.e. egg mimicry). To counter this adaptation in the parasite, hosts can produce eggs with similar appearance within clutches (low intraclutch variation) as well as eggs with diverging appearance between different clutches (high interclutch variation). Many North American passerines are utilised as hosts by the brown-headed cowbird (Molothrus ater). However, this parasite generally lays non-mimetic eggs. As predicted, we found that European passerines had a lower intraclutch variation and a higher interclutch variation in egg appearance than North American passerines.

However, the difference in intraclutch variation between the continents was less than expected. A relationship has previously been found among European passerines between the rejection rate of non-mimetic eggs and clutch variation in egg appearance, and this is thought to reflect the stage in the coevolution between parasite and host. We found no evidence of such patterns among North American species. These results provide support for the hypothesis that specific host clutch variation is a counteradaptation against parasite egg mimicry.

We investigated whether there was any difference in clutch variation between acceptors and rejecters of parasitic eggs within populations of three European passerines; reed warblers (Acrocephalus scirpaceus), chaffinches (Fringilla coelebs), and blackcaps (Sylvia atricapilla). In a Czech reed warbler population with an intermediate rejection rate of non-mimetic cuckoo eggs, it was found that rejecters had a statistically significant lower intraclutch variation than acceptors of such eggs. Age or conditional stimuli did not seem to have any influence on the rejectionbehaviour. A similar experiment was carried out in a Norwegian chaffinch population and a Czech blackcap population, which, however, were experimentally parasitised with foreign conspecific eggs because they are both very good rejecters of nonmimetic parasitic eggs. We found no difference in intraclutch variation among acceptors and rejecters of foreign eggs in chaffinches and blackcaps. However, it was found that the rejection of conspecific eggs greatly depends upon the contrast (i.e. mimicry) between the parasitic and their own eggs. It therefore seems that even though individuals have the ability to reject foreign eggs, limitations in their cognitive system entails that parasitic eggs that are too similar to the host eggs will be accepted. We also looked for potential effects of age on rejection behaviour and intraclutch variation, but no relationship between these variables was found. The results indicate that in these three species both rejection behaviour and clutch variation are more or less innate features, and also that there is a genetically based linkage between recognition of odd eggs and intraclutch variation in egg appearance.

2) Many hosts of brood parasites show no or only intermediate rejection rates of foreign non-mimetic eggs. Evolution of proper rejection behaviour could be prevented by costs related to egg rejection. Important in this respect are erroneous rejection of their own eggs in non-parasitised nests (recognition errors) and rejection of their own eggs in addition to the parasitic egg in parasitised clutches (rejection costs). Because successful cuckoo parasitism usually is detrimental to the breeding success of the host, only recognition errors are believed to be important as an opposing selective pressure against proper host defence in cuckoo hosts. We examined whether such costs exist in chaffinches and blackcaps. These species maintain a high rejection rate of foreign eggs, even though they are not currently used as hosts by the cuckoo. We therefore predicted that recognition errors should be absent or at least rare in these species. We found support for this prediction; rejection costs were relatively high but recognition errors were at best rare events.

In another investigation, we proposed a hypothesis (the "spatial habitat structure hypothesis") based upon metapopulation dynamics and characteristics concerning host breeding habitats to explain the variation in rejection behaviour found among European passerines. This hypothesis is based upon the fact that the cuckoo, as well as other avian brood parasites, needs access to vantage points in trees to monitor host nests, and thus only species breeding near trees are available as hosts. Our results were very much in accordance with this hypothesis. Species that breed both near and far away from trees are the best cuckoo hosts, because gene flow from non-parasitised populations breeding far from trees will prevent the evolution of proper rejection behaviour in parasitised populations breeding near trees. However, species that always breed near trees have high rejection rates because the majority of the populations have been utilised as hosts, and thus there has been a strong selection for the evolution of host defences. Furthermore, the level of parasite egg mimicry and the level of parasitism was found to be highest among hosts breeding both near and far away from trees, indicating that the cuckoo is most successful when utilising such species as hosts.

Paper VI is not included as a paper in this thesis, but is included as the introduction.

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29

Silva, Emmanuel Moralez da. "Garça-vaqueira (Bulbucus ibis): a diversidade genética no estudo do comportamento reprodutivo e na caracterização da população invasora brasileira". Universidade Federal de São Carlos, 2013. https://repositorio.ufscar.br/handle/ufscar/5406.

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The genetic diversity of the cattle egret (Bubulcus ibis) was analyzed to investigate reproductive behavior and characterize Brazilian populations of the species. Genotypes at seven microsatellite loci were used to investigate the occurrence of more than one female laying eggs in the same nest, characterizing the occurrence of multiple maternity. DNA was extracted from swabs collected from the outer surface of eggs and sexed; males were excluded. Forty-eight clutches from two breeding seasons (2010 and 2011) were genetically analyzed. Thirty-nine eggs laid by a second or third female were recorded. In five nests, the first egg of the clutch was from a different female, the laying happening prior to that of the incubating female. Suggesting nest takeover by another pair of egrets that kept the pre-existing eggs together with its own clutch. In the other 43 nests, the hypothesis of brood parasitism was posed to explain why one or two additional females were found laying eggs in a nest. A 463-bp fragment of the mitochondrial DNA control region Domain I was amplified for 148 individuals from seven Brazilian populations to investigate genetic-population and demographic parameters. Genetic diversity indices, the population structure tests Fst and AMOVA, a haplotype network, mismatch distribution and neutrality tests (Tajima s D, Fu s Fs, Fu and Li s D* and F*, Ramos-Onsins and Rozas R2) revealed the following: i) a high level of diversity was recorded for the cattle egret in Brazil in comparison to other closely related species studied in the country; ii) genetic diversity levels determined for the Brazilian regions are similar; iii) genetic structuring was not observed between the seven studied populations; and iv) the different tests performed to determine demographic expansion revealed no significant results. This is the first genetic characterization study for Bubulcus ibis to date and the findings indicate a high degree of plasticity in reproductive behavior and confirm a marked dispersion behavior of the species, leading to the homogenization of Brazilian populations.
A diversidade genética da garça-vaqueira (Bubulcus ibis) foi utilizada para se investigar o comportamento reprodutivo e para se caracterizar populações brasileiras da espécie. Genótipos em locos de microssatélites foram utilizados na detecção da presença de mais de uma fêmea ovipositando em um mesmo ninho, o que pode caracterizar a ocorrência de maternidade múltipla. O DNA extraído dos swabs coletados na superfície externa dos ovos foi sexado e eventuais amostras de machos foram excluídas. Quarenta e oito ninhadas, de duas temporadas reprodutivas (2010 e 2011) foram analisadas geneticamente. Foram registrados 39 ovos ovipositados por uma segunda ou terceira fêmea. Em 33 ninhos foram encontrados genótipos distintos de duas fêmeas e em seis ninhos genótipos de três fêmeas. Em cinco ninhos o primeiro ovo na sequência de oviposição mostrou-se ser de uma fêmea diferente, tendo a oviposição acontecido previamente àquela da fêmea incubante. Esse achado foi explicado supondo a tomada de ninho por um segundo casal de garças, com a manutenção do ovo pré-existente juntamente com os da própria ninhada. Nos outros 43 ninhos, a presença das fêmeas extras foi explicada hipotetizando a ocorrência de parasitismo de ninho intraespecífico. Um fragmento de 463 pb do Domínio I da região controladora do DNA mitocondrial foi amplificado para 148 indivíduos para a investigação de parâmetros genéticopopulacionais e processos demográficos nas sete populações estudadas. A estimativa de índices de diversidade genética, testes de estruturação populacional Fst e AMOVA, a construção de uma rede de relação entre haplótipos, a análise de mudanças no tamanho populacional pela mismatch distribution e a realização de testes de neutralidade (D de Tajima, Fs de Fu, D* e F* de Fu e Li, R2 de Ramos-Onsins e Rozas) permitiram identificar: i) um nível alto de diversidade genética para B. ibis no Brasil, quando comparado a espécies proximamente relacionadas estudadas no país; ii) níveis semelhantes de diversidade genética determinados para as regiões brasileiras; iii) ausência de estruturação genética entre as sete populações estudadas; e iv) ausência de sinais de expansão demográfica pelos testes realizados. Os resultados aqui apresentados são os primeiros resultados genéticos na espécie até o momento e apontam para uma alta plasticidade no comportamento reprodutivo e confirmam a dispersão bastante acentuada da espécie, levando a homogeneização das populações brasileiras.

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30

Mines, Ben Michael. "Interactions between the brood parasitic whydahs and their hosts in southern Africa". Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619948.

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Börner, Martina. "The life history of brood parasites : co-evolutionary constraints and competitive begging". Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608752.

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32

Dearborn, Donald C. "Nestling behavior of a brood parasite : food acquisition and predation risk of brown-headed cowbirds /". free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9837723.

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33

Conley, David C. (David Charles). "Hatching, copepodid survival and larval development of Salmincola edwardsii (Crustacea:Copepoda) on brook trout (Salvelinus fontinalis)". Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61189.

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Salmincola edwardsii is an ectoparasitic copepod typically found on the gills of brook trout (Salvelinus fontinalis). Laboratory experiments were conducted to determine: (i) the effects of temperature and photoperiod on early life cycle events, and (ii) the rate of larval development to adult. Egg incubation time, duration of copepodid swimming activity and copepodid survival time all decreased with increasing temperature. Different photoperiods had no effect. Hatching duration and hatching success were not influenced by either temperature or photoperiod. Copepodids remained alive and active for up to 16 days at 8$ sp circ$ and 5 days at 20$ sp circ$C. Adult male copepods were observed at 3 to 8 days after host exposure. They lived for up to 3 days. Adult females became permanently attached to hosts between 11 and 16 days post-infection.

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34

Albert, Elaine. "Parasite acquisition in relation to brook trout Salvelinus fontinalis population structure in a subarctic lake". Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61846.

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Miño, Carolina Isabel. "Genética de populações e relações de parentesco em Ciconiiformes (Aves)". Universidade Federal de São Carlos, 2010. https://repositorio.ufscar.br/handle/ufscar/5386.

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Universidade Federal de Sao Carlos
Population genetic parameters and genetic relatedness estimates were carried out for Roseate Spoonbill (Platalea ajaja), Wood Stork (Mycteria americana) and Great Egret (Ardea alba egretta) reproductive colonies in Amapa, Pantanal and Rio Grande do Sul (RS), Brazil. Microsatellite genotypes were used to investigate kinship patterns between nestlings sampled inside the same nests, using a variety of analytical approaches. Unrelated nestling-pairs were observed in Roseate Spoonbill nests (6.12% of analyzed nests) and in Wood Stork nests (11.34%); half-siblings were present in Roseate Spoonbill nests as well (1.36%). Only full-siblings were detected inside Great Egret nests. Conspecific brood parasitism (CBP) and extra-pair paternity were proposed to account for the presence of unrelated nestmates and half-siblings, respectively, in Roseate Spoonbill and Wood Stork nests. Those results suggest the occurrence of a mating system different than genetic monogamy in natural populations of those waterbirds. Genetic relatedness was also investigated for adults and offspring, as well as for supposed siblings in Roseate Spoonbill families kept in three zoological facilities in the U.S. Paternity and maternity allocation analyses through maximum-likelihood revealed that errors were present in zoo‟s studbooks in relation to the familial records. We also identified mating between related individuals that were not detected previously by zookeepers. Population genetic parameters were also estimated and demographic processes were assessed for Great Egret reproductive colonies in the Pantanal and Rio Grande do Su, Brazil. Bayesian clustering analyses, assignment tests, analysis of molecular variance, F-statistics estimates, allelic frequency distribution and the G-W index revealed that: i) Pantanal reproductive colonies are genetically differentiated from Rio Grande do Sul colonies; ii) an IBD-like pattern alone cannot explain that differentiation; and iii) genetic signal of a reduction of population size was present for two colonies in the Pantanal and one in Rio Grande do Sul. Results were discussed considering a metapopulation dynamic and also considering that populations from both Brazilian regions represent distinct units and deserve to be treated separately when planning and carrying out conservation and management programs that aim to preserve the species‟ genetic diversity.
Estudos de genética de populações e de parentesco genético foram desenvolvidos em colhereiro (Platalea ajaja), cabeça-seca (Mycteria americana) e garça-branca-grande (Ardea alba egretta), de colônias reprodutivas do Amapá, Pantanal e Rio Grande do Sul (RS), Brasil. Genótipos em locos de microssatélites foram utilizados para se investigar os padrões de relacionamento entre ninhegos amostrados dentro dos mesmos ninhos com diferentes metodologias de análise. Pares de ninhegos não-relacionados foram encontrados nos ninhos de colhereiro (6,12% dos pares analisados) e de cabeça-seca (11,34%); meio-irmãos foram observados nos ninhos de colhereiro (1,36%). Em garça branca grande foi detectada apenas a presença de irmãos-completos dentro dos ninhos. Parasitismo de ninho intraespecífico e paternidade extra-par podem explicar a presença de ninhegos não-relacionados e meio-irmãos nos ninhos de colhereiro e cabeça-seca, o que indica a presença de um sistema de acasalamento diferente da monogamia genética nas populações naturais dessas espécies. Relações de parentesco entre adultos e filhotes e entre supostos irmãos foram determinadas em famílias de colhereiro de três zoológicos dos EUA. Análises de atribuição de maternidade e paternidade por máxima verossimilhança revelaram erros nos registros dos zoológicos quanto às relações progenitor-progênie e identificaram acasalamentos entre indivíduos aparentados que não tinham sido registrados. Parâmetros genético-populacionais e processos demográficos foram investigados em populações de garça-branca-grande do Pantanal e do Rio Grande do Sul. Análises Bayesianas, testes de alocação de indivíduos, análises de variância molecular, estimativa de estatísticas F, exame da distribuição das freqüências alélicas e cálculo do índice de G-W permitiram identificar que: i) há diferenciação genética significativa entre colônias reprodutivas do Pantanal e do Rio Grande do Sul; ii) o padrão de isolamento pela distância não explica essa diferenciação; e iii) duas populações no Pantanal e uma população no RS apresentaram sinais genéticos de redução demográfica. Os resultados foram discutidos considerando que as populações de garça-branca-grande localizadas no Pantanal e no Rio Grande do Sul são unidades populacionais independentes e devem se tratar separadamente no planejamento e desenvolvimento de programas de manejo para a conservação da diversidade genética total da espécie.

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36

Wright, Bernard James. "Effects of intensive stock reduction on a brook trout population and its parasite community". Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60691.

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The brook trout population in a 4.7 hectare subarctic lake was sampled in 1986 and intensively fished in 1987, 1988 and 1989 in order to study the effect of stock depletion on fish parasite transmission. Population density was originally high, with slow individual growth rates, and small maximum size. Brook trout bore infections of Eubothrium salvelini, Phyllodistomum umblae, Crepidostomum farionis and Diplostomum sp. as well as some rare parasites. After intensive fishing the growth rates and size of the remaining fish increased. In 1987 all parasites increased in abundance. E. salvelini decreased in 1988 whereas the abundance of the other parasites remained high. In 1989 two new parasites, Echinorhynchus lateralis and Philonema sp. appeared. Parasite community changes and improves fish growth were related to trout diets and the pattern of intermediate host consumption. In 1987 zooplankton feeding increased. It then declined in 1988 and 1989 as populations of large benthic invertebrate prey increased. Feeding shifts may also have been mediated in part by intraspecific competition and aggression.

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Shull, Heather C. "Demography, selection and comparative molecular evolution in brood parasitic indigobirds (vidua spp.) and their firefinch (lagonosticta spp.) hosts". Thesis, Boston University, 2012. https://hdl.handle.net/2144/31601.

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Thesis (Ph.D.)--Boston University
PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
The interaction of natural selection and genetic drift is key to understanding patterns of genomic variation and the adaptation of organisms to their environments. I examined how demographic and selective factors shape patterns of genetic variation at the Major Histocompatibility Complex (MHC) in three species of brood parasitic indigobirds ( Vidua spp.) and their firefinch hosts (Lagonosticta spp.). These two genera experience similar ecological and physiological conditions due to their close contact and shared environment as nestlings, but they have vastly different demographic histories. I characterized variation at the second exon of Class IIB MHC loci by 454 amplicon sequencing. Results suggest a minimum of three to four putatively functional MHC Class IIB loci. Balancing selection appears to outweigh genetic drift to maintain nearly equal variation at MHC loci in the two genera, despite estimates from neutral loci indicating that indigobirds have a long-tetm effective population size about one-tenth that of firefinches. Balancing selection at MHC is likely influenced by avian haematozoan parasites. I compared malarial infections in indigobirds and firefinches by amplifying and sequencing a portion of the haematozoan cytochrome b gene from avian blood samples. Indigo birds exhibit a lower prevalence of avian malaria than firefinches and other sympatric estrildids, but share more parasite lineages with their hosts than they do with non-hosts. A reduction in parasite load due to reduced reproductive effort may be a general life history advantage of brood parasitism, while close association in the nest may facilitate host-switching in some endoparasites. I found no significant relationships between MHC genotype and infection status in either indigobirds or firefinches. Shared genetic variation among species can also represent retained ancestral polymorphism, which is now widely recognized as a complicating factor in phylogeny estimation. The extent of retained ancestral polymorphism and discordance among gene trees should be a function of variable demographic history among lineages. Using firefinches as an example of a genus with a typical bifurcating evolutionary history, I reconstructed demographic and speciation history using a multi-locus coalescent method (BEST), which more appropriately incorporates the stochastic effects of genetic drift than single-locus or concatenation approaches, and found that gene tree incongruence correlated with time between divergence events but not with population sizes.
2031-01-01

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Waghchoure-Camphor, Elizabeth S. "Studies on the biology and control of Tropilaelaps clareae : Asian parasitic brood mites in Apis mellifera colonies in Islamabad Pakistan". Thesis, Cardiff University, 1998. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364646.

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Hanekom, Marc C. "The effect of brood and queen pheromones, as well as the colony environment, in the success of Apis mellifera capensis social parasites". Thesis, Link to the online version, 2007. http://hdl.handle.net/10019/426.

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Melathopoulos, Adony P. "Laboratory and field evaluation of neem pesticides for the control of honey bee mite parasites Varroa jacobsoni and Acarapis woodi and brood pathogens Paenibacillus larvae and Ascophaera apis". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51417.pdf.

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41

Bazin, Ronald C. "Defences against brood parasitism in the eastern kingbird". 1991. http://hdl.handle.net/1993/12127.

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42

Medina-Guzman, Iliana. "Macroevolutionary outcomes of coevolution between avian brood parasites and their hosts". Phd thesis, 2016. http://hdl.handle.net/1885/101811.

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Almost one hundred bird species in the world are known to be obligate interspecific brood parasites. These lay their eggs in the nests of other species, their hosts, which take care of a usually larger parasitic chick. Brood parasitism constitutes one of the best examples of coevolution in the animal kingdom. This strategy is usually costly to the host, and has led to the evolution of a suite of adaptations in hosts, in order to defend themselves against parasitism, and in parasites, in order to effectively parasitize their hosts. In this thesis I explore the effects of brood parasitism on macro-evolutionary patterns in both hosts and parasites. In the first six chapters of my thesis I explore how defences evolve in hosts. First I present a literature review about the evolution of egg acceptance and tolerance mechanisms in hosts of brood parasites, in which I discuss how other co-evolutionary interactions, such as those between plants and herbivores, may be informative for understanding brood parasitic systems. In the second chapter I perform a large-scale comparative analysis on the evolution of clutch size as a tolerance mechanism in hosts. This chapter also incorporates a mathematical model and a field experiment on the Horsfield’s bronze-cuckoo Chalcites basalis. In the third chapter I investigate why one type of defence, egg rejection, evolves in some host species and not in others. In the fourth chapter I present a comparative analysis which tests the idea that the benefits of group defence against brood parasites has led to the evolution of cooperative breeding in hosts. For the fifth and sixth chapters, I describe field experiments to test the evolution of defences in the yellow-rumped thornbill (Acanthiza chrysorrhoa), the main host of the shining bronze-cuckoo (Chalcites lucidus) in Australia. My main aim is to understand which types of defences have evolved in this major host. I also perform field experiments to understand which factors constrain the evolution of defences in this species. In the second part of my thesis I study how brood parasitism can be associated with the evolution of diversity in both hosts and parasites, especially in traits that are likely to be under selective pressures, such as the egg phenotype. In chapter 7 I study how egg phenotype has evolved to be more diverse within and among species that are hosts of brood parasites. In chapter 8 I explore whether a brood parasitic breeding strategy promotes the generation of new species and phenotypic diversity. Specifically, I test whether brood parasitic lineages have faster rates of speciation and phenotypic evolution. Finally, in chapter 9, I discuss how together, these chapters offer a broad evolutionary landscape that demonstrate the diverse impacts of brood parasitism as a co-evolutionary interaction. I provide evidence that brood parasitism, besides driving the evolution of defenses, is linked to trait diversity, and may be an important force behind the evolution of clutch size, cooperative breeding, egg pattern, egg size and plumage diversity.

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Clotfelter, Ethan D. "Impact of brown-headed cowbird brood parasitism on red-winged blackbirds and factors influencing patterns of parasitism". 1998. http://catalog.hathitrust.org/api/volumes/oclc/40742915.html.

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Lemos, Sharon A. C. "Host suitability in the Diderik cuckoo Chrysococcyx caprius - ploceid brood parasitism breeding system". Thesis, 2003. http://hdl.handle.net/10413/4816.

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Host suitability is critically important to the success of brood parasitism. Parasites must select a host that not only accepts its egg but also is capable of successfully rearing the parasite to fledging. Nearly all brood-parasites appear to avoid low-quality hosts that are likely to reject their eggs, that are of inappropriate size, or that feed their nestlings nutritionally inadequate or insufficient food. The diderik cuckoo, (Chrysococcyx caprius), is an obligate brood parasite known to parasitise a wide spectrum of ploceids, including the yellow weaver (Ploceus subaureus) and the southern red bishop (Euplectes orix). Theory predicts that brood parasites should exploit insectivorous passerines of similar adult size to themselves that provision large quantities of high protein food to their young. However, the relatively smaller granivorous red bishop is the most heavily parasitised host species of the diderik cuckoo in southern Africa. To investigate why an apparently unsuitable host species was so heavily parasitized several populations of parasitised red bishops and yellow weavers (omnivores) were studied in the Pietermaritzburg region, KwaZulu-Natal, South Africa. Host suitability was assessed by examining diet quality, host-provisioning rates, cuckoo nestling growth and cuckoo fledging success. Diderik cuckoo nestlings were provisioned the same diet as the host nestlings in red bishop and yellow weaver nests. However, cuckoos in bishop nests received a protein-deficient seed diet from as early as six days following hatching. In contrast, weaver-cuckoo faeces contained 1~ times more insect than their bishop counterparts throughout their nestling period. Provisioning rates by bishop females were significantly slower than by yellow weavers, and neither bishop nor weaver hosts showed any 'supernormal' effort when feeding a young cuckoo. Both host species provisioned cuckoo nestlings at a similar rate and with a similar food mass as their own nestlings. Diderik cuckoos in bishop nests grew at a slower rate and fledged in a poorer condition than their yellow weaver counterparts. Red bishops are likely the most exploited host of the diderik cuckoo because i) cuckoo eggs are more readily accepted by the less discriminating bishop and ii) the bishop-breeding season coincides more closely with that ofthe diderik cuckoo than the yellow weaver. Thus, diderik cuckoos may preferentially exploit bishop hosts because of the low frequency of cuckoo egg rejection, which ultimately results in many cuckoos fledging from bishop nests despite the lowquality diet provisioned and 53% (n = 53) fledging success in nests of this species. In the yellow weaver system, the protein-rich diet and the greater probability of cuckoo nestling survival (80%, n = 5) may compensate for the high rejection rate of cuckoo eggs by this host. Thus, both host systems seem to represent evolutionary compromises for the diderik cuckoo, with neither red bishops nor yellow weavers being entirely ideal as host species.
Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.

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Underwood, Todd J. "Proximate and ultimate influences on egg recognition and rejection behaviour in response to avian brood parasitism". 2004. http://hdl.handle.net/1993/15737.

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46

Klippenstine, Dwight Russell. "Can egg mimicry by brown-headed cowbirds explain the acceptance of brood parasitism by grassland passerines?" 2005. http://hdl.handle.net/1993/18095.

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47

Curson, David R. "Nest predation and brood parasitism of passerine birds in pinyon-juniper woodland in northeast New Mexico". 1996. http://catalog.hathitrust.org/api/volumes/oclc/36668003.html.

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Thesis (M.S.)--University of Wisconsin--Madison, 1996.
Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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48

Fonnesbeck, Christopher James. "The abundance, distribution and brood parasitism of upland-breeding warbling vireos in a fragmented forest landscape". Thesis, 1998. http://hdl.handle.net/2429/8081.

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In a two-year study of the Warbling Vireo Vireo gilvus, I explore patterns of distribution, habitat, and brood parasitism along an elevation gradient in the South Okanagan region, British Columbia using landscape analyses. The Warbling Vireo is threatened at low elevations in the Okanagan by intense parasitism pressure by Brown-headed Cowbirds Molothrus ater. Vireo persistence may depend upon neighbouring source populations in the montane forests overlooking the valley. In the first part of the study, I found brood parasitism to be significantly lower in higher elevation forests compared to the valley. Cowbirds are less and parasitise fewer species upland. Of sampled nests, only the Warbling Vireo is parasitised frequently, with approximately 30 percent of all nests suffering parasitism in the forest. Such low levels of cowbird activity are likely due to food limitation, since host species dominate the songbird community. Levels of upland parasitism were not linearly correlated with proximity to the valley, either due to sampling error or to local-scale ecological factors. Forest cover appears to affect parasitism levels, with most parasitism occurring on sites of moderate tree density. The second part of my study employs variables derived from digital forest inventory maps that are used to predict Warbling Vireo distribution and avian species richness across the Okanagan Forest at two spatial scales. The presence of vireos is positively correlated with early serai stage variables at both the local stand level and the landscape level. At the landscape scale, species richness is associated positively with habitat diversity, and negatively with mature forest area in a multiple regression model. Though sustained industrial forestry in the Okanagan Forest may enhance avian diversity and Warbling Vireo habitat alike, the frequency of vireo detections is significantly lower at higher elevation. This reduces the likelihood that montane forest is a source of Warbling Vireos for the valley, in spite of decreased parasitism pressure in upland habitat.

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Abernathy, Virginia. "Investigating the first stages of coevolution between the Pacific koel and its newest host,the red wattlebird". Phd thesis, 2017. http://hdl.handle.net/1885/128297.

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Avian obligate brood parasites lay their eggs in the nests of other bird species and never provide their own parental care. This behaviour is a model example of coevolution and while multiple studies and reviews have discussed the different types of adaptations and counter-adaptations hosts and brood parasites evolve, there have only been a handful of empirical studies focused on how quickly coevolution can occur in a host-brood parasite system. Additionally, little is known about the early stages of brood parasite and host coevolutionary interactions. Understanding the rates of coevolution between brood parasites and their hosts is an important step in uncovering aspects about the process of speciation, determining which traits represent true genetic change and can aid in conservation decisions of endangered potential hosts, especially as brood parasites expand their breeding ranges with environmental changes. I investigated these issues by capitalising on the recent exploitation of the Red Wattlebird (Anthochaera carunculata) by the brood-parasitic Pacific Koel (Eudynamys orientalis). I conducted a literature review on factors that influence the rate of coevolution between avian obligate brood parasites and their hosts and performed observational and experimental studies at two sites where wattlebirds have experienced different durations of parasitism: Sydney (parasitism for 38-86 years) and Canberra (parasitism for 8-33 years). I determined that host switching can pose challenges for both the host and brood parasite, as parasitised wattlebird nests fledged significantly fewer young than unparasitised wattlebird nests, but fledged similar numbers of wattlebird and koel young. The koel’s later breeding season relative to the wattlebird’s and the koel’s poor timing of egg laying may have contributed to the low success of koel eggs. Mobbing experiments demonstrated that naïve hosts can learn to recognise a brood parasite within 33 years or less, but the speed at which this defence spreads throughout the population may be constrained by low parasitism rates. Egg rejection experiments indicated that more than 38 years is required for egg ejection to evolve in wattlebirds, as they only ejected model eggs at an extremely low rate in Sydney and Canberra, while two older hosts showed high levels of ejection at both sites. Lastly, I found evidence that the koel likely evolved mimicry of the eggs of one of its old hosts, which allowed it to exploit several other host species, including the wattlebird, due to all of its hosts having similar egg morphology. My results support the many theoretical models which agree that at least 30 or more years is required for egg ejection alleles to spread throughout a population. This process may be slowed because wattlebird eggs appear so similar to koel eggs, making it more difficult for wattlebirds to recognise parasitic eggs. However, I discovered that naïve hosts without specific anti-parasite traits can still utilise generalised defences, such as mobbing, in order to reduce the impact of brood parasitism, and that host switching can also be difficult for the brood parasite, as it may not be well-adapted to the new host’s breeding season or behavioural habits.

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Guigueno, Melanie Francoise. "Acceptance or Rejection of Cowbird Parasitism: Cues Used in Decision-Making by Yellow Warblers (Dendroica petechia)". 2010. http://hdl.handle.net/1993/3958.

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The proximate causes triggering nest abandonment are unclear for most species, including the Yellow Warbler (Dendroica petechia), which abandons nests parasitized by cowbirds (via burial or desertion). Cowbird parasitism and rejection of parasitism are costly to some hosts; therefore cues affecting their responses have important evolutionary implications. Manipulative experiments showed that experimentally adding a cowbird egg elicited similar rejection frequencies (2008: 31.8%; 2009: 26.1%) as naturally laid eggs (2008: 27.1%; 2009: 20.0%). In 2008, interaction with an egg-removing model increased the probability of abandonment and the most aggressive individuals were more likely to bury the model cowbird egg. In 2009, eggs added to nests before sunrise were rejected at a frequency (29.7%) similar to eggs added to nests after sunrise (22.9%). Warblers returning to nests after egg addition peered significantly longer at their clutch than at control nests, shuffled their bodies more frequently when on the eggs and spent more time probing eggs with their bill once settled on their parasitized clutch. Furthermore, although non-mimetic blue eggs were not abandoned significantly more frequently than cowbird eggs (blue 31.1% versus cowbird 21.4%), only blue eggs were ejected from some nests. Thus, warblers use both tactile and visual cues to detect the presence of a parasitic egg in their nest. Eggs added to nests were not rejected at a lower frequency than naturally parasitized nests, as was recorded in a previous study. It is difficult to know whether this increase in abandonment of experimental eggs is due to phenotypic plasticity, genetic changes, or other factors. Egg recognition abilities may have changed because I have shown that the warblers’ behaviour changes before versus after egg addition, whereas no changes were recorded in an earlier study. Finally, not all individuals that buried eggs for the first time in 2009 (21.4%) buried again after being re-parasitized (5.3%), when less time remained in the breeding season relative to the first parasitism event. This suggests that egg rejection and host responsiveness in warblers, and likely other avian hosts that use abandonment as a form of rejection, is affected by environmental cues which may act as genetic expressers.

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