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Journal articles on the topic 'Lamna nasus'

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Published: 7 June 2025
Last updated: 26 June 2025

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1

Cameron, Luke W. J., William Roche, Peter Green, Jonathan D. R. Houghton, and Paul J. Mensink. "Transatlantic movement in porbeagle sharks, Lamna nasus." Fisheries Research 207 (November 2018): 25–27. http://dx.doi.org/10.1016/j.fishres.2018.05.014.

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2

Stevens, J. D. "Further results from a tagging study of pelagic sharks in the north-east Atlantic." Journal of the Marine Biological Association of the United Kingdom 70, no. 4 (1990): 707–20. http://dx.doi.org/10.1017/s0025315400058999.

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A further 69 recaptures are reported from a tagging study of pelagic sharks initiated in 1970 in the north-east Atlantic. Galeorhinus galeus tagged in England were recaptured in the eastern Atlantic from southern Spain to north-west of Iceland. Among the 42 G. galeus recaptured the longest time at liberty was about 12 years and the greatest distance travelled was 2461 km. Among the 21 Prionace glauca recaptured the l ongest time at liberty was 10.7 years, and seven sharks moved distances between 4362 and 7176 km. One shark tagged in south-west England was recaptured in the South Atlantic off South America. An Isurus oxyrinchus was at liberty for 4–6 years and a Lamna nasus for up to about 13 years. Lamna nasus were recaptured from northern Norway to northern Spain. The growth rates of the tagged sharks were close to the predicted values for G. galeus, were slower for P. glauca and faster for L. nasus.
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3

Haugen, Janne, Gregory Skomal, Tobey Curtis, and Steven Cadrin. "Interdisciplinary stock identification of North Atlantic porbeagle (Lamna nasus)." Journal of Northwest Atlantic Fishery Science 53 (April 19, 2022): 1–18. http://dx.doi.org/10.2960/j.v53.m732.

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We conducted an interdisciplinary review of available information (i.e., genetics, life-history, and movement) to evaluate the stock structure of a previously targeted shark species, the porbeagle (Lamna nasus), in the North Atlantic. Most available information supports the conclusion that porbeagle consist of a single genetic population in the North Atlantic, which is relevant for determining species conservation status. However, the observed movement rates between the Northwest, Northeast Atlantic, and the Mediterranean appear to be low enough to consider separate spatial units for stock assessment and fishery management. The review reveals different interpretations among the organizations involved with the conservation, management, and assessments of porbeagle in the North Atlantic regarding biological population and stock boundaries. Differences in the spatial definition of management units among management organizations may pose an impediment to conserving porbeagle populations and achieving management objectives. We recommend an increased collaboration between organizations involved in highly migratory shark species as it would be beneficial for data collection, data inclusiveness, the robustness of assessments, and provide clarity for fishery managers, scientists, and the public on stocks and status. This review demonstrates that the interdisciplinary approach to stock identification is particularly valuable for data-limited species because no single approach typically has enough information to be definitive. Clearly defining management units that reflect the biological populations of porbeagle in the North Atlantic is expected to reduce uncertainty in stock assessments and help achieve current management and conservation goals of rebuilding North Atlantic porbeagle stocks.
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4

Cortés, Federico, and Juan A. Waessle. "Hotspots for porbeagle shark (Lamna nasus) bycatch in the southwestern Atlantic (51°S–57°S)." Canadian Journal of Fisheries and Aquatic Sciences 74, no. 7 (2017): 1100–1110. http://dx.doi.org/10.1139/cjfas-2016-0114.

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Fisheries bycatch can severely affect the population status of species with low resilience such as sharks. Bycatch monitoring is an important issue for the development of conservation and management plans for these species. The main objectives of this study were to quantify and model the spatiotemporal trend of bycatch for porbeagle shark (Lamna nasus) in the Argentinean surimi trawl fleet to identify hotspots in the southwestern Atlantic Ocean. Using onboard observer data, we have demonstrated that L. nasus was usually caught as bycatch by the surimi trawl fleet operating in the southern limits of the southwestern Atlantic (51°S–57°S), representing an important part of the reported catch for the Atlantic Ocean. Delta and Tweedie models indicated that bycatch had a relatively stable trend, was concentrated in a limited region of the study area, and was associated with spatiotemporal, operational, environmental, and prey availability variables. The model with the best predictive capability used for the spatial delineation of hotspots for L. nasus bycatch showed that the areas located south of 54°12′S and over the continental shelf-break were critical for the porbeagle conservation and management strategies in the southwestern Atlantic Ocean.
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5

Ellis, J. R., and S. E. Shackley. "Notes on porbeagle sharks, Lamna nasus, from the Bristol Channel." Journal of Fish Biology 46, no. 2 (1995): 368–70. http://dx.doi.org/10.1111/j.1095-8649.1995.tb05976.x.

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6

Mollen, Frederik H., and John W. M. Jagt. "The taxonomic value of rostral nodes of extinct sharks, with comments on previous records of the genus Lamna (Lamniformes, Lamnidae) from the Pliocene of Lee Creek Mine, North Carolina (USA)." Acta Geologica Polonica 62, no. 1 (2012): 117–27. http://dx.doi.org/10.2478/v10263-012-0005-z.

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ABSTRACT Mollen, F.H. and Jagt, J.W.M. 2012. The taxonomic value of rostral nodes of extinct sharks, with comments on previous records of the genus Lamna (Lamniformes, Lamnidae) from the Pliocene of Lee Creek Mine, North Carolina (USA). Acta Geologica Polonica, 62 (1), 117-127. Warszawa. Shark rostral nodes from the Yorktown Formation (Zanclean, early Pliocene) of Lee Creek Mine, North Carolina (USA), previously assigned to the genus Lamna Cuvier, 1816, have been reinterpreted using a preliminary identification key for extant Lamniformes based on rostral morphology. In addition, the fossil rostral nodes have been compared in detail with Recent material of both the porbeagle, Lamna nasus (Bonnaterre, 1788) and the salmon shark, Lamna ditropis Hubbs & Follet, 1947. Despite the fact that the rostra compared relatively well with those of Recent Lamna, the Lee Creek Mine specimens proved to differ significantly in having near-parallel lateral rostral cartilages that join the rostral node individually, instead of abutting ones. Based on this observation, we here propose to strike the genus Lamna from the Lee Creek Mine faunal list, so long as no other diagnostic material is forthcoming. These partially preserved rostra are likely to have belonged to extinct taxa within the families Lamnidae or Otodontidae, both of which have been documented from the Yorktown Formation on the basis of isolated teeth of at least three species, Cosmopolitodus hastalis (Agassiz, 1838), Megaselachus megalodon (Agassiz, 1835) and Parotodus benedenii (Le Hon, 1871).
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7

Díaz-Jaimes, Píndaro, Manuel Uribe-Alcocer, Douglas H. Adams, Jose Miguel Rangel-Morales, and Natalia J. Bayona-Vásquez. "Complete mitochondrial genome of the porbeagle shark, Lamna nasus (Chondrichthyes, Lamnidae)." Mitochondrial DNA Part B 1, no. 1 (2016): 730–31. http://dx.doi.org/10.1080/23802359.2016.1233465.

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8

MOLLEN, FREDERIK H., SABINE P. WINTNER, SAMUEL P. IGLÉSIAS, SEAN R. VAN SOMMERAN, and JOHN W. M. JAGT. "Comparative morphology of rostral cartilages in extant mackerel sharks (Chondrichthyes, Lamniformes, Lamnidae) using CT scanning." Zootaxa 3340, no. 1 (2012): 29. http://dx.doi.org/10.11646/zootaxa.3340.1.2.

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A comparative study of rostral morphology of extant mackerel sharks (Lamniformes, Lamnidae) is presented. Based oncomputed tomography (CT) scans of fresh specimens, 3D reconstructions, dried museum chondrocrania and the availableliterature, detailed morphological descriptions of the rostral cartilages are provided for the type species of all three extantlamnid genera, namely Carcharodon carcharias (Linnaeus, 1758), Isurus oxyrinchus Rafinesque, 1810 and Lamna nasus(Bonnaterre, 1788), and compared with those of I. paucus Guitart Manday, 1966 and L. ditropis Hubbs & Follett, 1947.Despite intraspecific variation, the rostral cartilages of all extant lamnids present significant differences that allow genus-and species-level identification, which is especially of use to identify fossil rostral nodes of these particular taxa. The maindifferences were found to be in overall calcification of the rostrum (Lamna > Isurus > Carcharodon), general configura-tion of the rostral open space, position of the base of the lateral rostral cartilages, (non-)abutting lateral cartilages, (absent)rostral keels and shape of the rostral node. In cross section, the base of the rostral node is rounded in Lamna, Y-shaped in Isurus and uncalcified in juvenile and subadult Carcharodon (tesserae absent).
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9

Nicolaus, E. E. Manuel, Victoria A. Bendall, Thi P. C. Bolam, Thomas Maes, and Jim R. Ellis. "Concentrations of mercury and other trace elements in porbeagle shark Lamna nasus." Marine Pollution Bulletin 112, no. 1-2 (2016): 406–10. http://dx.doi.org/10.1016/j.marpolbul.2016.07.047.

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10

Cameron, Luke W. J., William K. Roche, Jonathan D. R. Houghton, and Paul J. Mensink. "Population structure and spatial distribution of porbeagles (Lamna nasus) in Irish waters." ICES Journal of Marine Science 76, no. 6 (2019): 1581–90. http://dx.doi.org/10.1093/icesjms/fsz046.

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Abstract Porbeagles throughout the North Atlantic have experienced severe population decline through overfishing, with the northeastern population listed as critically endangered. Management of this population is constrained by the paucity of data on porbeagle population structure, distribution and behaviour in this region. Here we use a long-term (47 year) Irish capture-mark-recapture dataset to investigate the population structure, spatial distribution and seasonal movements of this species. From 1970–2017, a total of 268 sharks (9 recaptures) were ID tagged, with most individuals likely being juvenile based on length at maturity estimates (mean total length = 143.9 cm, SD = 35.4). Almost all captures were recorded at three distinct locations near angling hubs along the south, west and north coasts with catches peaking in August. Long-term trends in capture date indicated a shift towards earlier capture dates in the northern site (n = 153). Our findings suggest Irish waters may act as a persistent summer aggregation site for juveniles, which show evidence for seasonal site fidelity, returning to nearby locations between years. These findings demonstrate the utility of such programmes, which can be implemented, with minimal expense by engaging with the angling sector, to elucidate the population structure and distribution of wide-ranging fish species.
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11

Chiaramonte, Gustavo, Ana Alarcos, Diego Vazquez, et al. "ecurrent juvenile stranding of the porbeagle shark Lamna nasus along the South West Atlantic coast." Revista del Museo Argentino de Ciencias Naturales 26 (2024): 171–84. https://doi.org/10.22179/revmacn.26.836.

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12

Bendall, Victoria A., Jonathan L. Barber, Alexandra Papachlimitzou, et al. "Organohalogen contaminants and trace metals in North-East Atlantic porbeagle shark (Lamna nasus)." Marine Pollution Bulletin 85, no. 1 (2014): 280–86. http://dx.doi.org/10.1016/j.marpolbul.2014.05.054.

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13

Pazzagli, Luigia, Giampaolo Manao, Gianni Cappugi, et al. "The amino acid sequences of two acylphosphatase isoforms from fish muscle (Lamna nasus)." Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology 1387, no. 1-2 (1998): 264–74. http://dx.doi.org/10.1016/s0167-4838(98)00134-4.

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14

Campana, S. E., and W. N. Joyce. "Temperature and depth associations of porbeagle shark (Lamna nasus) in the northwest Atlantic." Fisheries Oceanography 13, no. 1 (2004): 52–64. http://dx.doi.org/10.1111/j.1365-2419.2004.00236.x.

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15

Maisey, John G., and Victor G. Springer. "Chondrocranial Morphology of the Salmon Shark,Lamna ditropis, and the Porbeagle,L. nasus(Lamnidae)." Copeia 2013, no. 3 (2013): 378–89. http://dx.doi.org/10.1643/cg-12-130.

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16

Haugen, Janne B., and Yannis Papastamatiou. "Observation of a porbeagle shark Lamna nasus aggregation at a North Sea oil platform." Journal of Fish Biology 95, no. 6 (2019): 1496–99. http://dx.doi.org/10.1111/jfb.14149.

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17

Semba, Yasuko, Kotaro Yokawa, Hiroaki Matsunaga, and Hiroshi Shono. "Distribution and trend in abundance of the porbeagle (Lamna nasus) in the southern hemisphere." Marine and Freshwater Research 64, no. 6 (2013): 518. http://dx.doi.org/10.1071/mf12272.

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Knowledge of a species’ distribution is an important element in its effective management and conservation. The porbeagle (Lamna nasus) is a common by-catch shark in the tuna longline fishery in the southern hemisphere, but its distribution and abundance are largely unknown. The investigation of observer data from the tuna longline fishery and other fishery survey data has revealed that (1) porbeagles are distributed in the pelagic waters across the oceans of the southern hemisphere, (2) juveniles and adults are distributed in cooler environments than are neonates, (3) pregnant females occur in the pelagic waters of the Indian Ocean and the Tasman Sea, most being frequently recorded around the Cape of Good Hope between June and July and (4) the standardised catch per unit effort (CPUE) based on tuna longline fishery (1994–2011) and driftnet survey (1982–1990) data indicate no continuous decreasing trend in the abundance of the southern porbeagle, contrary to the declining trend reported in a limited region in the South Atlantic. Considering its circumglobal distribution, stock status of this population should be assessed using information from the areas of its major distribution, including pelagic waters, and international coordination across oceans is necessary for the effective management of this population.
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18

Larsen, Christina, Hans Malte, and Roy E. Weber. "ATP-induced Reverse Temperature Effect in Isohemoglobins from the Endothermic Porbeagle Shark (Lamna nasus)." Journal of Biological Chemistry 278, no. 33 (2003): 30741–47. http://dx.doi.org/10.1074/jbc.m301930200.

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19

Saunders, Ryan A., François Royer, and Maurice W. Clarke. "Winter migration and diving behaviour of porbeagle shark, Lamna nasus, in the Northeast Atlantic." ICES Journal of Marine Science 68, no. 1 (2010): 166–74. http://dx.doi.org/10.1093/icesjms/fsq145.

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Abstract Saunders, R. A., Royer, F., and Clarke, M. W. 2011. Winter migration and diving behaviour of porbeagle shark, Lamna nasus, in the Northeast Atlantic. – ICES Journal of Marine Science, 68: 166–174. The porbeagle is one of the top marine predators in the North Atlantic. However, little is known about its biology, abundance, or spatial ecology there. Results are presented on the migration and behaviour of three porbeagles tagged with archival pop-up tags off Ireland between September 2008 and January 2009. One shark migrated >2400 km to the northwest of Morocco, residing around the Bay of Biscay for approximately 30 days. The other two remained more localized in off-shelf regions around the Celtic Sea/Bay of Biscay and off western Ireland. The sharks occupied a broad vertical depth range (0–700 m) and a relatively limited temperature range (∼9–17°C), with notable variations in diving behaviour between individual sharks. There were distinct day–night differences in depth distribution, each shark being positioned higher in the water column by night than by day. Night-time depth distribution also appeared to be driven by the lunar cycle during broad-scale migration through oceanic waters. Our results show that porbeagles occupy and traverse regions of high fishing activity where they are potentially vulnerable to population depletion. Such large-scale movement outside the ICES Area underlines the need for international coordination in their assessment and management.
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20

Natanson, Lisa J., Gregory B. Skomal, Sarah L. Hoffmann, Marianne E. Porter, Kenneth J. Goldman, and David Serra. "Age and growth of sharks: do vertebral band pairs record age?" Marine and Freshwater Research 69, no. 9 (2018): 1440. http://dx.doi.org/10.1071/mf17279.

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Inaccurate age estimates can have severe consequences in the management of elasmobranchs. Numerous studies in shark age validation have demonstrated a disconnect between band pair counts and age, resulting in age underestimation, particularly in older individuals. To investigate the relationship between band pairs, vertebral shape and growth, we quantified intracolumn differences in centrum morphology (size and structure) and band pair counts in seven shark species: Squatina dumeril, Carcharodon carcharias, Lamna nasus, Isurus oxyrinchus, Alopias vulpinus, Prionace glauca and Carcharhinus obscurus. In all species examined, band pair deposition was closely related to body girth and the structural properties of the cartilaginous skeleton, relative to maximum size, and body type. These results have strong implications for accurately assessing age for fisheries management of these species.
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21

Joyce, W. "Analysis of stomach contents of the porbeagle shark (Lamna nasus Bonnaterre) in the northwest Atlantic." ICES Journal of Marine Science 59, no. 6 (2002): 1263–69. http://dx.doi.org/10.1006/jmsc.2002.1286.

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22

Cassoff, Rachel M., Steven E. Campana, and Sigmund Myklevoll. "Changes in baseline growth and maturation parameters of Northwest Atlantic porbeagle, Lamna nasus, following heavy exploitation." Canadian Journal of Fisheries and Aquatic Sciences 64, no. 1 (2007): 19–29. http://dx.doi.org/10.1139/f06-167.

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We tested for density-dependent changes in growth and maturation of Northwest Atlantic porbeagle (Lamna nasus) after the population declined by 75%–80% from fishing. Vertebrae and reproductive data collected from the virgin (1961–1966) and exploited (1993–2004) populations were analysed to test for differences in growth rate and age and length at maturity between the time periods. We detected significant differences between reparameterized von Bertalanffy growth models for each period, using likelihood ratio tests. Beyond an age of 7 years, mean length at age was greater during 1993–2004 than during 1961–1966. Between 1961–1963 and 1999–2001, length at maturity decreased in males (from 179 to 174 cm curved fork length (CFL)) and was invariant in females (216 cm CFL), whereas age at maturity declined in both males (from 8 to 7 years) and females (from 19 to 14 years). An analysis of porbeagle temperature associations indicated that sharks occupied comparable temperature conditions during the mid-1960s and 1990s, ruling out the possibility of temperature-induced growth changes. The observed increase in growth rate and decrease in age at maturity following exploitation support the hypothesis of a compensatory density-dependent growth response.
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23

Collareta, Alberto, Simone Casati, and Andrea Di Cencio. "The porbeagle shark, Lamna nasus (Elasmobranchii: Lamniformes), from the late Pliocene of the central Mediterranean Basin." Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen 287, no. 3 (2018): 307–16. http://dx.doi.org/10.1127/njgpa/2018/0718.

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24

Campana, Steven E., Warren Joyce, and Mark Fowler. "Subtropical pupping ground for a cold-water shark." Canadian Journal of Fisheries and Aquatic Sciences 67, no. 5 (2010): 769–73. http://dx.doi.org/10.1139/f10-020.

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Porbeagle sharks ( Lamna nasus ) are large pelagic sharks apparently restricted to the cold temperate waters of the northern and southern hemispheres. Despite considerable knowledge of their biology, their pupping (birthing) grounds have never been identified. Pop-up archival transmission tags applied to 21 sharks off eastern Canada indicated that males and immature sharks of both sexes remained primarily on the continental shelf for periods of up to 348 days after tagging. However, mature female porbeagles migrated up to 2356 km through the winter, at depths down to 1360 m beneath the Gulf Stream, to a subtropical pupping ground in the Sargasso Sea. In addition to this pupping ground being well south of their documented range, the placement of such a key life history stage in international, largely unregulated waters poses problems for the conservation and management of a species that is largely fished in Canadian waters.
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25

Jung, Armelle, Arthur Ory, Paul Abaut, and Lucas Zaccagnini. "First Use of Free-Diving Photo-Identification of Porbeagle Shark (Lamna nasus) off the Brittany Coast, France." Diversity 16, no. 3 (2024): 155. http://dx.doi.org/10.3390/d16030155.

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A large number of pelagic shark species have declined significantly in recent decades due to overfishing, bycatch, and habitat degradation. Whereas porbeagle sharks have become scarce due to a reduction in their populations around the world, recent stock evaluations are giving positive signals about the evolution of the North-Eastern Atlantic stock size. The porbeagle shark (Lamna nasus), an offshore pelagic species with a wide distribution, is designated by IUCN as Globally Vulnerable and Critically Endangered for Europe and subject to various international conservation conventions. An increasing number of observations are reported off the Brittany coast of Trégor. The ecological role of this area for the species is still unknown and greater knowledge is needed to develop and apply sustainable management measures on a local and international scale. This study represents the first use of photo-identification on porbeagle sharks in order to improve the ecological knowledge of the species in the Trégor area. These results confirm the effectiveness of this method, with 19 of the 131 individuals identified being re-sighted, indicating an interesting degree of site fidelity and showing a sex ratio of 100% females. Observations of individuals over several years allowed the researchers to discuss the relevance of the different types of marks. The findings suggest that the Trégor area off the Brittany coast serves as a seasonal residence for female porbeagle sharks, especially between May and October. This study represents a successful first step in the use of photo-identification for this species. It offers technical support for the sharing of the methodology and provides some biological knowledge allowing researchers to discuss potential sustainable management measures for the conservation of porbeagle sharks in the study area and their habitats while needed.
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26

Lacroix, Gilles L. "Large pelagic predators could jeopardize the recovery of endangered Atlantic salmon." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 3 (2014): 343–50. http://dx.doi.org/10.1139/cjfas-2013-0458.

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Long-term population viability of Bay of Fundy Atlantic salmon (Salmo salar) is threatened by high levels of marine mortality during migration. Pop-up satellite archival tags on repeat spawners provide direct evidence of extensive natural mortality of migrating salmon in coastal zones attributed to predation by large pelagic fish and no evidence of fishing mortality. Ingested tags show that salmon with a coastal migration are eaten by porbeagle shark (Lamna nasus) inside the Bay of Fundy, whereas distant migrants are consumed by Atlantic bluefin tuna (Thunnus thynnus) and other apex predators along the Scotian Shelf. Mortality is clustered in a few zones because of similar predator–prey habitat preferences and overlapping migration paths. The extent of predation in salmon populations with different migration strategies can account for observed decline rates in neighbouring populations with different life histories. The impact on endangered salmon populations that rely on multiple repeat spawners for population stability may be sufficient to hamper ongoing recovery efforts.
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27

Abdullah, Asadatun, Apta Yatma, and Nurjanah. "Application of mitochondrial gene markers and real-time PCR for the identification of Isurus spp. and Lamna nasus species." BIO Web of Conferences 112 (2024): 08003. http://dx.doi.org/10.1051/bioconf/202411208003.

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Sharks are predator species that play an important role in marine ecosystems and have high economic value. Exploiting shark parts, including fins, scales, teeth, cartilage, skin, liver, meat, and tails, is difficult to identify visually, necessitating molecular identification to determine traded shark products. This study aimed to design species-specific primers based on mitochondrial gene markers for shark species Isurus spp. and Lamna nasus, and their application in real-time PCR-based fisheries product authentication. The research was conducted in silico for specific primer design and in vitro for DNA sample isolation, DNA quantity and quality testing, DNA amplification, and real-time PCR analysis. The primer pairs of species included in the CITES II list with different genetic markers have been successfully created. The primers used were able to amplify DNA and showed a Ct difference between the target and non-target DNA, proving their ability to identify the target shark species.
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28

Francis, Malcolm P., John C. Holdsworth, and Barbara A. Block. "Life in the open ocean: seasonal migration and diel diving behaviour of Southern Hemisphere porbeagle sharks (Lamna nasus)." Marine Biology 162, no. 11 (2015): 2305–23. http://dx.doi.org/10.1007/s00227-015-2756-z.

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29

Biais, Gérard, Yann Coupeau, Bernard Séret, et al. "Return migration patterns of porbeagle shark (Lamna nasus) in the Northeast Atlantic: implications for stock range and structure." ICES Journal of Marine Science 74, no. 5 (2017): 1268–76. http://dx.doi.org/10.1093/icesjms/fsw233.

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During two surveys in 2011 and 2013, we deployed pop-up satellite archival tags (PSATs) on subadult or adult porbeagles at the Bay of Biscay shelf break. We collected data that enabled the reconstruction of nine migrations (eight females, one male) that uncover the large spatial extent of these sharks in the Northeast Atlantic. The mean duration of each deployment was 292 d, with four reaching 365 d. The reconstructions show that, after migrations that extended up to 2000 km away from the point of release, the tagged porbeagles returned to their location of tagging. All the reconstructed migrations followed the same general pattern of a migration away from the Bay of Biscay in late summer, and a return in spring the following year. The total distance of the migrations was estimated at 5000–13 000 km for PSATs deployed for a full year (n = 4), with examples of migration to the Arctic Circle, southward to Madeira and westward to the mid-Atlantic Ridge. The observed site fidelity to the Bay of Biscay and the common migration pattern of all females provide evidence of complex spatial structure and dynamics that encompasses both the open ocean and heavily fished coastal areas, and highlights the challenge of assessing and managing the porbeagle stock in this area.
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30

Jambura, Patrick L., Pero Ugarković, Mišo Pavičić, et al. "New Evidence for the Contemporary Presence of Juvenile White Sharks (Carcharodon carcharias) in the Adriatic Sea." Fishes 10, no. 1 (2025): 25. https://doi.org/10.3390/fishes10010025.

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The presence of the white shark (Carcharodon carcharias) in the Mediterranean Sea is well documented, but mainly through historical and opportunistic records. Historically, the Adriatic Sea, particularly its eastern coastline, was considered a hotspot for white sharks, with relatively frequent reports of juvenile specimens suggesting a potential nursery area. However, since the second half of the 20th century, the abundance of white sharks in the Adriatic has experienced a dramatic decline, with the last confirmed sighting recorded in 2011. In this study, we report the recent capture of a young-of-the-year (YOY) white shark off the Croatian coast, previously misidentified as a porbeagle shark (Lamna nasus). In addition, we revisit historical records of white sharks in the Adriatic Sea to assess whether this region can be considered a nursery area. Our findings highlight significant gaps in the understanding of white shark spatial ecology and reproductive biology in the Mediterranean Sea. Furthermore, this study emphasizes the critical role citizen science and public engagement can play in documenting occurrences of these elusive and endangered predators, offering valuable insights for future conservation efforts.
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31

Campana, Steven E. "Transboundary movements, unmonitored fishing mortality, and ineffective international fisheries management pose risks for pelagic sharks in the Northwest Atlantic." Canadian Journal of Fisheries and Aquatic Sciences 73, no. 10 (2016): 1599–607. http://dx.doi.org/10.1139/cjfas-2015-0502.

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The shortfin mako (Isurus oxyrinchus), porbeagle (Lamna nasus), and blue shark (Prionace glauca) are three frequently caught shark species in the northwestern Atlantic Ocean. Satellite tagging studies show that all three species range widely across many national boundaries but spend up to 92% of their time on the high seas, where they are largely unregulated and unmonitored. All are caught in large numbers by swordfish and tuna fishing fleets from a large number of nations, usually unintentionally, and all are unproductive by fish standards, which makes them particularly sensitive to fishing pressure. Landing statistics that grossly underrepresent actual catches, unreported discards that often exceed landings, and high discard mortality rates are threats to the populations and roadblocks to useful population monitoring. The influence of these threats is greatly magnified by inattention and ineffective management from the responsible management agency, the International Commission for the Conservation of Atlantic Tunas (ICCAT), whose prime focus is the more valuable swordfish and tuna stocks. Although practical management options are available, none will be possible if organizations like ICCAT continue to treat sharks like pests.
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Francis, Malcolm P., Steven E. Campana, and Cynthia M. Jones. "Age under-estimation in New Zealand porbeagle sharks (Lamna nasus): is there an upper limit to ages that can be determined from shark vertebrae?" Marine and Freshwater Research 58, no. 1 (2007): 10. http://dx.doi.org/10.1071/mf06069.

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Annual deposition of growth bands in vertebrae has been validated for many shark species, and is now widely regarded as the norm. However, vertebrae are part of the shark’s axial skeleton, and band deposition may stop in old sharks when somatic growth ceases. We aged vertebral sections from New Zealand porbeagle sharks (Lamna nasus) under reflected white light and using X-radiographs. Bomb radiocarbon assays supported vertebral age estimates up to ~20 years, but not at older ages. The results suggest that older porbeagles were under-aged by as much as 50% from vertebral band counts, presumably because band width declined to a point where it became unresolvable. This has important implications for growth studies on other long-lived sharks. Estimated ages at sexual maturity were 8–11 years for males and 15–18 years for females, and longevity may be ~65 years. New Zealand and North Atlantic porbeagles differ in these parameters, and in length at maturity and maximum length, suggesting genetic isolation of the two populations.
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Campana, Steven E., Lisa J. Natanson, and Sigmund Myklevoll. "Bomb dating and age determination of large pelagic sharks." Canadian Journal of Fisheries and Aquatic Sciences 59, no. 3 (2002): 450–55. http://dx.doi.org/10.1139/f02-027.

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Despite their notoriety and role as apex predators, the longevity of large pelagic sharks such as the porbeagle (Lamna nasus) and shortfin mako (Isurus oxyrinchus) is unknown. Vertebral growth bands provide an accurate indicator of age in young porbeagle, but age validation has never been reported for any large shark species past the age of sexual maturity. Here, we report the first application of bomb radiocarbon as an age validation method for long-lived sharks based on date-specific incorporation of radiocarbon into vertebral growth bands. Our results indicate that porbeagle vertebrae recorded and preserved a bomb radiocarbon pulse in growth bands formed during the 1960s. Through comparison of radiocarbon assays in young, known-age porbeagle collected in the 1960s with the corresponding growth bands in old porbeagle collected later, we confirm the validity of porbeagle vertebral growth band counts as accurate annual age indicators to an age of at least 26 years. The radiocarbon signatures of porbeagle vertebral growth bands appear to be temporally and metabolically stable and derived mainly from the radiocarbon content of their prey. Preliminary radiocarbon assays of shortfin mako vertebrae suggest that current methods for determining shortfin mako age are incorrect.
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Francis, Malcolm P., Lynda H. Griggs, and Susan Jane Baird. "Pelagic shark bycatch in the New Zealand tuna longline fishery." Marine and Freshwater Research 52, no. 2 (2001): 165. http://dx.doi.org/10.1071/mf00086.

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Tuna longline effort declined from 23—26 million hooks per year in 1979mdash;82 to 2mdash;4 million hooks per year in 1995mdash;98. Scientific observer coverage averaged 7.5%since 1988mdash;89, but increased in 1992mdash;93 (mean 23%). Observed catch per unit effort (CPUE) and the numbers of hooks set were used to estimate shark catches. Between 1988mdash;89 and 1997mdash;98,about 450 000 blue sharks (Prionace glauca), 65 000 porbeagles (Lamna nasus ) and 25 000 shortfin makos (Isurus oxyrinchus) were caught. In 1997mdash;98,about 45 000 blue sharks, 4000 porbeagles and 3000 makos were caught. Corresponding weight estimates were 1400 t, 150 t and 200 t. CPUE varied between foreign and domestic vessels, between north and south regions and among years, but there were no consistent temporal trends. Most males and females were immature, and most sharks were alive when recovered. Most sharks were processed, but usually only the fins were retained. The New Zealand tuna longline fishery is probably not seriously affecting pelagic shark stocks, but adequate assessment is not currently feasible. Accurate monitoring of Pacific Ocean catches is an important first step towards ensuring sustainability of their populations.
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Natanson, Lisa J., Bethany M. Deacy, Warren Joyce, and James Sulikowski. "Presence of a resting population of female porbeagles (Lamna nasus), indicating a biennial reproductive cycle, in the western North Atlantic Ocean." Fishery Bulletin 117, no. 1-2 (2019): 70–77. http://dx.doi.org/10.7755/fb.117.1-2.8.

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36

Francis, Malcolm P. "New Zealand shark fisheries: development, size and management." Marine and Freshwater Research 49, no. 7 (1998): 579. http://dx.doi.org/10.1071/mf97076.

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New Zealand’s shark fisheries have increased steadily since 1975 to reach 17 000–19 000 t per year. Commercial fisheries catch mainly spiny dogfish (Squalus acanthias), school shark (Galeorhinus galeus), skates (Raja nasuta and R. innominata), ghost sharks (Hydrolagus novaezealandiae and Hydrolagus sp.), rig (Mustelus lenticulatus) and elephantfish (Callorhinchus milii). School shark, rig and elephantfish fisheries have long histories, and catches are limited by Individual Transferable Quotas. Fisheries for spiny dogfish, skates and ghost sharks have only developed since 1979. Spiny dogfish and skate landings are partially regulated by total quotas. Other sharks are prohibited target species. Blue (Prionace glauca), porbeagle (Lamna nasus) and mako (Isurus oxyrinchus) sharks are taken as by-catch of the tuna longline fishery. There is a small recreational catch of spiny dogfish, school shark, rig, mako shark and blue shark. Historically important Maori fisheries for spiny dogfish, school shark and rig are now minor. A beach netting programme has operated off Dunedin beaches since 1969 to protect swimmers from shark attacks. Fisheries management measures include commercial quotas, prohibitions on target fishing many species, recreational bag limits, limits on set-net length, mesh size and soak time, and closure of many inshore waters to set-netting, trawling and Danish seining.
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Pade, Nicolas G., Nuno Queiroz, Nicolas E. Humphries, et al. "First results from satellite-linked archival tagging of porbeagle shark, Lamna nasus: Area fidelity, wider-scale movements and plasticity in diel depth changes." Journal of Experimental Marine Biology and Ecology 370, no. 1-2 (2009): 64–74. http://dx.doi.org/10.1016/j.jembe.2008.12.002.

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38

Mc Nicholl, Darcy G., Les N. Harris, Tracey Loewen, et al. "Noteworthy occurrences among six marine species documented with community engagement in the Canadian Arctic." Animal Migration 8, no. 1 (2021): 74–83. http://dx.doi.org/10.1515/ami-2020-0113.

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Abstract Arctic marine ecosystems are changing, one aspect of which appears to be distributional expansions of sub-arctic species. For Arctic marine systems, there is limited occurrence information for many species, especially those found in restricted habitats (e.g., ice-covered, far north, or deep-water). Increasing observations through on-going Fisheries and Oceans Canada (DFO) community-based monitoring programs (e.g., Arctic Coast, Cambridge Bay Arctic Char stock assessment, Arctic Salmon, and Kugluktuk coastal surveys), community observation networks, and local media have augmented opportunities to document new occurrences of marine fishes. Combined data from historical records and contemporary observations at the local scale can then delineate these among three types of occurrences: gradual distributional expansion, episodic vagrants, and rare endemics. Here we document nine occurrences of unusual sightings across six fish species (Pink Salmon Oncorhynchus gorbuscha, Bering Wolffish Anarhichas orientalis, Greenland Shark Somniosus microcephalus, Broad Whitefish Coregonus nasus, Banded Gunnel Pholis fasciata and Salmon Shark Lamna ditropis) from six northern Canadian communities and classify the nature of each observation as rare, vagrant, or expanding distributions. Uniting scientific and local observations represents a novel approach to monitor distributional changes suitable for a geographically large but sparsely populated area such as the Canadian Arctic. The new occurrences are important for discerning the potential effects of the presence of these species in Arctic ecosystems. These observations more broadly will build on our understanding of northern biodiversity change associated with warming Arctic environments.
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Campana, Steven E., Warren Joyce, Mark Fowler, and Mark Showell. "Discards, hooking, and post-release mortality of porbeagle (Lamna nasus), shortfin mako (Isurus oxyrinchus), and blue shark (Prionace glauca) in the Canadian pelagic longline fishery." ICES Journal of Marine Science: Journal du Conseil 73, no. 2 (2015): 520–28. http://dx.doi.org/10.1093/icesjms/fsv234.

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40

FARRELL, A. P., P. S. DAVIE, and R. SPARKSMAN. "The absence of coronary arterial lesions in five species of elasmobranchs, Raja nasuta, Squalus acanthias L., Isurus oxyrinchus Rafinesque, Prionace glauca (L.) and Lamna nasus (Bonnaterre)." Journal of Fish Diseases 15, no. 6 (1992): 537–40. http://dx.doi.org/10.1111/j.1365-2761.1992.tb00686.x.

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41

Pratt, Joseph, Stephen Turnbull, Pamela Emery, and Donald McAlpine. "Prevalence, Intensity, and Site of Infection of Echthrogaleus Coleoptratus (Guérin-Méneville, 1837) (Siphonostomatoida, Pandaridae), Ectoparasitic on the Porbeagle Shark (Lamna Nasus) in the Bay of Fundy, Canada." Crustaceana 83, no. 3 (2010): 375–79. http://dx.doi.org/10.1163/001121610x12627655658203.

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42

Höltke, Olaf, Erin E. Maxwell, and Michael W. Rasser. "A Review of the Paleobiology of Some Neogene Sharks and the Fossil Records of Extant Shark Species." Diversity 16, no. 3 (2024): 147. http://dx.doi.org/10.3390/d16030147.

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In recent years, new findings and new methods (stable isotopes of oxygen, zinc, and nitrogen; 2D and 3D modeling; and geometric morphometric analyses of the teeth) have enhanced our knowledge of the Neogene shark fauna and its paleobiology. Several papers deal with the large Otodus (Megaselachus) species, including the construction of a 3D model, as well as insights into its lifestyle and diet. In addition, the skeletal remains of Carcharias gustrowensis, Carcharodon hastalis, and Keasius parvus and a natural tooth set of Carcharodon hubbelli have been described in the last 13 years, and the dentition of the Neogene species Carcharoides catticus, Megachasma applegatei, and Parotodus benedenii has been reconstructed. Stable isotope analyses of the teeth from the Neogene species of Araloselachus, Carcharias, Carcharodon, Galeocerdo, Hemipristris, and Mitsukurina have given insights into the trophic positions of these genera during the Neogene, and shark teeth preserved near the skeletal remains of prey animals (mammals) and shark bite traces on these remains provide direct evidence of trophic interactions. The tooth shape, fossil locality, and paleoenvironment have been used to better understand the taxa Carcharhinus dicelmai, Megalolamna paradoxodon, Pachyscyllium dachiardii, and P. distans. Among extant species, Galeorhinus galeus can be traced back to the Eocene. Alopias superciliosus, Rhincodon typus, and possibly A. vulpinus can be traced back to the Oligocene. Species present by the Miocene include Alopias vulpinus, Carcharhinus amblyrhynchoides, C. amblyrhynchos, C. albimarginatus, C. amboinensis, C. brachyurus, C. brevipinna, C. falciformis, C. glaucus, C. leucas, C. limbatus, C. longimanus, C. macloti, C. obscurus, C. perezi, C. sealei, Centrophorus granulosus, Cetorhinus maximus, Dalatias licha, Deania calcea, Galeocerdo cuvier, Glyphis glyphis, Heptranchias perlo, Isurus paucus, Lamna nasus, Negaprion brevirostris, Odontaspis ferox, Pseudocarcharias kamoharai, Sphyrna media, S. mokarran, and possibly Carcharodon carcharias. First appearing in the Pliocene are Scymnodon ringens, Somniosus rostratus, and Zameus squamulosus. For some extant species (Carcharias taurus, Hexanchus griseus, Isurus oxyrinchus, Notorynchus cepedianus, and Sphyrna zygaena), it is not clear whether the assigned Neogene teeth represent the same species. The application of new methods to more fossil shark taxa, a detailed search for shark fossils, and better knowledge of the dentition of extant species (especially those with minute-sized teeth) will further enhance our knowledge of the evolution and paleobiology of sharks.
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43

Guzmán-Rivas, Fabián, Marco Quispe-Machaca, Jorge Lazo, et al. "Fatty acid profiles of highly migratory resources from the Southeastern Pacific Ocean, Chile: a potential tool for biochemical and nutritional traceability." PeerJ 13 (March 20, 2025): e19101. https://doi.org/10.7717/peerj.19101.

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The traceability of fish species and their resulting food products is essential to maintain the global supply of these goods, allowing us to distinguish and reconstruct the origin and history of their production chain. One way to trace food is through biochemical determinations, which aid in identifying their geographical origin quickly. This study analyzed the fatty acid (FA) profiles of highly migratory fishery resource species (HMRS) from the Southeastern Pacific Ocean (SEPO), and their use as potential tools to determine the geographic origin and nutritional condition of these marine resources. The fatty acids (FAs) presented in fillet or muscle tissue of 18 HMRS were measured as FA methyl esters by gas chromatography. Our results reveal that the swordfish Xiphias gladius presented the greatest variety of FAs, strongly characterized by the presence of saturated, monounsaturated, and polyunsaturated FAs. A similar trend of high diversity in all classes of FAs was observed in tuna species (i.e., Thunnus alalunga; T. albacares; T. obesus), oilfish (Ruvettus pretiosus) and escolar fish (Lepidocybium flavobrunneum). In turn, Lampris guttatus, Makaira indica, and Tetrapturus audax presented an intermediate variety of FAs and the highest amount of saturated and monounsaturated FAs of the evaluated species. Finally, Luvarus imperialis, Coryphaena hippurus and the sharks (Lamna nasus; Alopias vulpinus; Prionace glauca; Isurus oxyrinchus; Sphyrna zygaena) presented a low diversity of FAs, with only saturated FAs strongly predominating. Regarding the total concentration of FAs, the highest average values were recorded in X. gladius, L. flavobrunneum and R. pretiosus. The present study revealed notable differences in the FA compositions of the muscle of diverse HMRS from the SEPO off the coast of Chile, with the swordfish showing the healthiest FAs (i.e., mono and polyunsaturated) for human consumption. The data on FAs collected for HMRS could be used as a reference to characterize the FA profiles of other fisheries in the SEPO (e.g., coastal pelagic fishes). In an ecosystem approach, our findings help us to understand how essential nutrients (i.e., FA biomolecules) are transferred through the marine food web in the SEPO, revealing the diet type and/or feeding habits of HMRS considered as top predators. Furthermore, identifying the FA profiles of fishery resources at a spatial level provides crucial information for their management and conservation, particularly in those resources that are overexploited and also have a critical nutritional importance for human consumption.
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44

Rodriguez, Lauren Kelly, Bonis Lorenzo De, Jack McKee, et al. "Inter-laboratory ring test for environmental DNA extraction protocols: implications for marine megafauna detection using three novel qPCR assays." Metabarcoding and Metagenomics 9 (January 7, 2025): e128235. https://doi.org/10.3897/mbmg.9.128235.

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The comparability of methods applied to environmental DNA (eDNA) samples across laboratories remains a significant challenge for biodiversity monitoring on a global scale. Performance differences between protocols can jeopardize effective conservation strategies across regions and focal species. To address potential discrepancies amongst four international partners within a collaborative eDNA initiative, an inter-laboratory comparison (i.e., ring test) was conducted to compare efficiencies of established DNA extraction methodologies based on 39 eDNA samples. Each laboratory contributed eight to eleven samples collected throughout the North-East Atlantic and the Mediterranean Sea near sperm whales, porbeagle sharks, basking sharks, bottlenose dolphins and common dolphins. After lysis, aliquots were exchanged between laboratories before subsequent DNA extraction using each facility's preferred method. Extracts were returned to the lysates' respective laboratories of origin for measurements of total DNA concentration, as well as quantitative PCR using three novel species-specific assays for marine megafauna. Our findings revealed similar concentrations of total DNA, yet a significant reduction in extraction performance for targeted qPCR reactions by one laboratory, who has therefore modified their extraction method to be used for the remainder of this project. Overall, detection success differed based on the target taxa with sharks being less often detected (and at lower concentrations) than marine mammals. Significant interaction effects were found between combinations of laboratories and species, suggesting a link between extraction protocols and variable environmental conditions. Our study serves as a foundational step towards establishing reproducible practices that are crucial for the success of multinational eDNA projects to enable comparable results.
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45

Ruiz-C., R. I. D., and C. Román-Valencia. "Aspectos taxonómicos de Cetopsorhamdia boquillae y C. nasus (Pisces, Heptapteridae), con anotaciones sobre su ecología en la cuenca alta de los ríos Magdalena y Cauca, Colombia." Animal Biodiversity and Conservation 29, no. 2 (2006): 123–31. http://dx.doi.org/10.32800/abc.2006.29.0123.

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Taxonomic aspects of Cetopsorhamdia boquillae and C. nasus (Pisces, Heptapteridae), with annotations on their ecology from Magdalena and Cauca rivers upper basin, Colombia Ataxonomic analysis of Cetopsorhamdia boquillae and Cetopsorhamdia nasus from the Magdalena and Cauca river basin in Colombia is reported here based on fresh topotypical materials. Cetopsorhamdia boquillae can be differentiated from its congener by the color pattern, mainly concerning three dark lines: one on the supraoccipital bone, another at the dorsal fin base and a third at the caudal fin base. The pterygiophore of the dorsal fin first ray is inserted anterior to the ninth vertebra. C. nasus is readily distinguished from its congener by its lack of supraneural spines, fewer than 60 premaxilla teeth, the posterior edge of mesethmoid, and orbitonasal lamina joined by a cartilage band, and the shape of the frontal canal. Cetopsorhamdia boquillae can be distinguished from C. nasus by the length of the adipose-dorsal fin base (statistically significant) (F = 21, P = 0.05), the number of principal unbranched anal rays (5-6 in C. boquillae, 4 in C. nasus), and fewer vertebrae (36 in C. boquillae, 39 in C. nasus). Chemical, physical and ecological data are included to characterize the species habitats.
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46

Benz, George W., Andy Kingman, and Joanna D. Borucinska. "Gillnet survival and healing by a Porbeagle, Lamna nascus." Canadian field-naturalist 115, no. 3 (2001): 506–9. http://dx.doi.org/10.5962/p.363834.

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47

Hocking, P. J., P. J. Randall, D. De Marco, and I. Bamforth. "Assessment of the nitrogen status of field-grown canola (Brassica napus) by plant analysis." Australian Journal of Experimental Agriculture 37, no. 1 (1997): 83. http://dx.doi.org/10.1071/ea95068.

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Summary. Field trials were conducted over 2 seasons at Greenethorpe and Canowindra in the Cowra region of New South Wales to develop and calibrate plant tests for assessing the nitrogen (N) status of canola (Brassica napus). Plants were tested at 3 and 7 growth stages up to the start of flowering at Greenethorpe and Canowindra, respectively. The petiole of the youngest mature leaf (YML) was the most suitable plant part to sample for tests based on nitrate-N. Suitable plant parts for tests based on total N were the YML petiole or lamina, or the whole shoot. There was good agreement between the 2 sites in the just-adequate fertiliser N rates (rates giving 90% of maximum yield) and the critical N concentrations in the plant parts tested. Critical nitrate-N concentrations in the fresh YML petiole for dry matter production at the time of sampling the plants decreased from 1.62 to 0.14 mg nitrate-N/g fresh weight between the 4–5 leaf rosette stage (4–5 RS) and the start of flowering (SF). Critical nitrate-N concentrations in the dry YML petiole decreased from 16.5 to 0.8 mg/g dry weight between 4–5 RS and SF. Critical total N concentrations decreased from 4.5 to 2.0, 7.2 to 5.0 and 6.2 to 2.8% dry weight, in the YML petiole, YML lamina, and whole shoot, respectively, between 4–5 RS and SF. Critical nitrate-N and total N concentrations for assessing potential seed yield were similar to those for dry matter production at the time of sampling for each of the growth stages. The critical total N concentrations obtained for the YML petiole and lamina, and the whole shoot before the start of stem elongation are likely to be less precise than the critical nitrate-N concentrations in the YML petiole because of the limited response of total N concentrations to increasing rates of fertiliser N. However, total N in the YML petiole or lamina, or in the whole shoot may be a better indicator of N status for plants sampled after the start of stem elongation as nitrate-N concentrations become low and more variable, and it is harder to identify the YML. The decline in critical N concentrations must be taken into account when interpreting the results of plant tests for diagnosing the N status of canola, as sampling needs to correspond to the plant growth stage for which a particular critical N concentration has been obtained.
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48

Upadhyay, Rajesh Kumar. "Thanatosis impact of Athalianevadensis lacourt (Hymenoptera: Tenthredinidae), a case study on Brassica napus (l), at Ramgarh (Jharkhand, India)." PROCEEDINGS OF THE ZOOLOGICAL SOCIETY OF INDIA 23, no. 02 (2024): 247. https://doi.org/10.59467/pzsi.2024.23.247.

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Athelia nevadensis Lacourtis aninsect pest of Brassica napus widely distributed in Indian subcontinent. It comprises the great degree of adaptation to protect itself from predators as well as adverse climate. The larvae of Athalianevadensis Lacourthaving a special character when it feel any disturbance or threat it falls down on ground from the host plant , turn curl and show feigning death to confuse the predators, later theyspeedily escape to cracks of soil or under the fallen leaves this character is called thanatosis. Larvae of the pest feed on the leaves of the host plant. It is the only infective stage damage the crop of Brassica napus (L) and tender a significant loss to the farmers of Ramgarh (Jharkhand,India ) .Brassica napus ( L ) is an important cash crop.Farmers cultivate it for marketing; green shoot of this plant as edible green vegetable (sarso sag) later as seed for oil and various uses. Infestation not onlydecline the production of crop but it directly decline the financial status of farmers also.Athelia nevadensis Lacourt is a small insect about 05mm to 6.6mm long orange yellow in colour.It is active in morning and evening. The female lay egg singly at the margin of tender leaves in morning and evening. After incubation period tinygrubs appear,and voraciously feed the lamina of leaf and skeletonise it. The infested host plant retarder in their growth, flowers and seed production.Infestations on Brassica napus is very difficult to control. To makeeffective pest management strategies attractthe researcher to observe the impact on pest and execute for effective control of pest. Farmers are advised for biological control, and apply some parasite as Perilissus cingulator and bacterium serratia marcescens.For quick relief chemical control require Malathion,fenitrothion,endosulphan and quinalphos application.. KEYWORDS :Insect,adaptation,climate,survival,crop,feigning death, biological control, chemical control.
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49

Griffiths, M., and N. G. Simms. "Observations on the anatomy of mammary glands in two species of conilurine rodent (Muridae: Hydromyinae) and in an opossum (Marsupialia: Didelphidae)." Australian Mammalogy 16, no. 1 (1993): 9. http://dx.doi.org/10.1071/am93002.

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The pups of Pseudomys nanus and P. australis are attached to their mothers' teats for extended periods of time, analogous to the situation encountered in pouchless marsupials. The structures in the mammary glands involved in facilitating prolonged attachment are different in the two rodent species and both kinds are different from those in marsupial glands including those of Monodelphis domestica, the subject of the present study. In P. nanus, the teats are anchored to postero-ventrally directed, tubular diverticula of the body wall. In P. australis there are no diverticula. However, support for the mammary glands and teats is afforded by the body wall, in the form of two well-developed fan-shaped muscles dorsal to the mammary glands in conjunction with a broad lamina of connective tissue, smooth and striated muscle situated between the skin of the belly and the mammary glands. In M. domestica, the teats are anchored to swathes of striated voluntary muscle, derived from the ilio-marsupialis muscles which pass ventrally through the secretory parenchyma to be inserted onto the bases of the teats. Since this musculature has not been observed in the mammary glands of any eutherians so far studied, nor in those of Monotremata, it is put that it is a character unique to the Marsupialia.
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50

"Lamna nasus." CABI Compendium CABI Compendium (January 7, 2022). http://dx.doi.org/10.1079/cabicompendium.77726.

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