To see the other types of publications on this topic, follow the link: Connectivité larvaire.
Journal articles on the topic 'Connectivité larvaire'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Connectivité larvaire.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Afandy, Zulfikar, Ario Damar, Syamsul Bahri Agus, and Budy Wiryawan. "CORAL LARVAL DISPERSAL MODEL ON CONSERVATION AREA OF KAPOPOSANG MARINE TOURISM PARK." Coastal and Ocean Journal (COJ) 1, no. 2 (2017): 39–51. http://dx.doi.org/10.29244/coj.1.2.39-51.
Full textAbstract:

 The availability of information related to the pattern of connectivity between coral reef is one of the key in coral reef conservation management. The identification of pattern of connectivity in the form of dispersion dynamics of coral larvae is very important as the development of coral reef itself is highly depended upon the external input, which this input must be accordingly managed in order to support the continuity of coral larvae supply. This research’s objectives are including to create the coral larvae dispersal model of Marine Protected Area (MPA) of Kapoposang. For instance, the modelling of coral larvae dispersal had been conducted using the biophysics modelling which combined the biological and physics factor in order to obtain the recruitment scenario and the traces of larvae dispersal. This simulation used coral larvae object with the Pelagic Larval Duration (PLD) for 30 days, the larvae release was conducted during the full moon and during the west and east monsoon. The result of the larvae dispersion model has indicated that the coral larvae dispersion process was influenced by the currents and variation of monsoons. Based coral connectivity pattern on Kapoposang found site Gondongbali, Kapoposang2, Suranti and Pamanggangang as a source. Then other location as sink by received larvae from other site are Gondongbali, Kapoposang, Pamanggangang, Taka Karangkarangang, Taka Pallawangang and Taka Palekko.
 
 
 Keywords
 connectivity, coral reef, larva dispersal, marine protected area, twp kapoposang
2
Fox, Alan D., Lea-Anne Henry, David W. Corne, and J. Murray Roberts. "Sensitivity of marine protected area network connectivity to atmospheric variability." Royal Society Open Science 3, no. 11 (2016): 160494. http://dx.doi.org/10.1098/rsos.160494.
Full textAbstract:
International efforts are underway to establish well-connected systems of marine protected areas (MPAs) covering at least 10% of the ocean by 2020. But the nature and dynamics of ocean ecosystem connectivity are poorly understood, with unresolved effects of climate variability. We used 40-year runs of a particle tracking model to examine the sensitivity of an MPA network for habitat-forming cold-water corals in the northeast Atlantic to changes in larval dispersal driven by atmospheric cycles and larval behaviour. Trajectories of Lophelia pertusa larvae were strongly correlated to the North Atlantic Oscillation (NAO), the dominant pattern of interannual atmospheric circulation variability over the northeast Atlantic. Variability in trajectories significantly altered network connectivity and source–sink dynamics, with positive phase NAO conditions producing a well-connected but asymmetrical network connected from west to east. Negative phase NAO produced reduced connectivity, but notably some larvae tracked westward-flowing currents towards coral populations on the mid-Atlantic ridge. Graph theoretical metrics demonstrate critical roles played by seamounts and offshore banks in larval supply and maintaining connectivity across the network. Larval longevity and behaviour mediated dispersal and connectivity, with shorter lived and passive larvae associated with reduced connectivity. We conclude that the existing MPA network is vulnerable to atmospheric-driven changes in ocean circulation.
3
Yund, Philip O., Charles E. Tilburg, and Michael A. McCartney. "Across-shelf distribution of blue mussel larvae in the northern Gulf of Maine: consequences for population connectivity and a species range boundary." Royal Society Open Science 2, no. 12 (2015): 150513. http://dx.doi.org/10.1098/rsos.150513.
Full textAbstract:
Studies of population connectivity have largely focused on along-shelf, as opposed to across-shelf, processes. We hypothesized that a discontinuity in across-shelf mixing caused by the divergence of the Eastern Maine Coastal Current (EMCC) from shore acts as an ecological barrier to the supply of mussel larvae to the coast. Existing data on the relative abundance of two congeneric blue mussels, Mytilus edulis and M. trossulus , were analysed to quantify the association of M. trossulus with the colder temperature signal of the EMCC and generate larval distribution predictions. We then sampled the across-shelf distribution of larvae along two transects during 2011. Larvae were identified using restriction digests of PCR amplicons from the mitochondrial 16S rDNA. Mytilus edulis larvae were consistently abundant on either the inshore and offshore transect ends, but not homogeneously distributed across the shelf, while M. trossulus larvae were less common throughout the study area. The divergence of the EMCC from shore appears to create a break in the connectivity of M. edulis populations by isolating those inshore of the EMCC from upstream larval sources. Across-shelf transport processes can thus produce connectivity patterns that would not be predicted solely on the basis of along-shelf processes.
4
Lu, Jiaying, Yuanjie Chen, Zihan Wang, et al. "Larval Dispersal Modeling Reveals Low Connectivity among National Marine Protected Areas in the Yellow and East China Seas." Biology 12, no. 3 (2023): 396. http://dx.doi.org/10.3390/biology12030396.
Full textAbstract:
Marine protected areas (MPAs) are vital for protecting biodiversity, maintaining ecosystem integrity, and tackling future climate change. The effectiveness of MPA networks relies on connectivity, yet connectivity assessments are often skipped in the planning process. Here we employed a multi-species biophysical model to examine the connectivity patterns formed among the 21 national MPAs in the Yellow and East China Seas. We simulated the potential larval dispersal of 14 oviparous species of five classes. Larvae of non-migratory species with pelagic larval duration (PLD) were assumed to be passive floating particles with no explicit vertical migration. A total of 217,000 particles were released according to spawning period, living depth, and species distribution, and they were assumed to move with currents during the PLD. Most larvae were dispersed around the MPAs (0–60 m isobaths) and consistent with the currents. Larval export increased with PLD and current velocity, but if PLD was too long, few larvae survived due to high daily mortality during pelagic dispersal. The overall connectivity pattern exhibited a north-to-south dispersal trend corresponding to coastal currents. Our results indicated that the national MPAs in the Yellow and East China Seas did not form a well-connected network and nearly 30% of them were isolated. These MPAs formed three distinct groups, one in the Yellow Sea ecoregion and two in the East China Sea ecoregion. Four MPAs (all in coastal Zhejiang) emerged as key nodes for ensuring multi-generational connectivity. Under the pressure of future climate change, high self-recruitment and low connectivity present significant challenges for building well-connected MPA networks. We suggest adding new protected areas as stepping stones for bioecological corridors. Focused protection of the Yellow Sea ecoregion could have a good effect on the southern part of the population recruitment downstream. Conservation management should be adjusted according to the life cycles and distributions of vulnerable species, as well as seasonal changes in coastal currents. This study provides a scientific basis for improving ecological connectivity and conservation effectiveness of MPAs in the Yellow and East China Seas.
5
Takeyasu, Kimika, Yusuke Uchiyama, Xu Zhang, Kosei Matsushita, and Satoshi Mitarai. "A Numerical Analysis on Coral Larval Networks across Reef Areas on the Northwest Coast of Okinawa Main Island, Japan." IOP Conference Series: Earth and Environmental Science 945, no. 1 (2021): 012030. http://dx.doi.org/10.1088/1755-1315/945/1/012030.
Full textAbstract:
Abstract Coral bleaching has recently occurred extensively over the world’s oceans, primarily due to high water temperatures. Mesophotic corals that inhabit at depths of approximately 30–150 m are expected to survive during bleaching events and to reseed shallow water corals afterward. In particular, in Okinawa, Japan, mesophotic coral ecosystems (MCEs) have been reported to serve as a refuge to preserve genotypic diversities of bleaching-sensitive corals. Connectivity of larval populations between different habitats is a key element that determines the area to be conserved for desirable coral ecosystems. Coral larvae generally behave passively to the surrounding currents and are transported by the advective and dispersive effects of ambient ocean currents. Thus, numerical ocean circulation models enable us to quantify connectivity with detailed spatiotemporal network structures. Our aim in this study is to quantify the short-distance and vertical connectivity of coral larvae in reef areas on the northwest coast of Okinawa Main Island. For the reason that both short-distance and vertical larval transport are influenced by complex nearshore topography, a very high-resolution 3-D circulation model is required. Therefore, we developed a quadruple nested high-resolution synoptic ocean model at a lateral spatial resolution of 50 m, coupled with an offline 3-D Lagrangian particle-tracking model. After validation of the developed model, short-distance horizontal coral connectivity across reef areas on the northwest coast was successfully evaluated. Furthermore, a series of Lagrangian particle release experiments were conducted to identify the vertical coral migration and 3-D connectivity required for the preservation of MCEs. The model revealed that coral larvae released from the semi-enclosed areas tended to remain near the source area, whereas they were diffused and dispersed gradually with time. The mesophotic corals were dispersed vertically to the deeper zone below the mixed layer, while upward transport occurred to induce the mesophotic corals to emerge near the surface, under the influence of the surface mixed layer. The model results solidly indicated significant connectivity between MCEs and shallow coral ecosystems.
6
Fobert, Emily K., Eric A. Treml, and Stephen E. Swearer. "Dispersal and population connectivity are phenotype dependent in a marine metapopulation." Proceedings of the Royal Society B: Biological Sciences 286, no. 1909 (2019): 20191104. http://dx.doi.org/10.1098/rspb.2019.1104.
Full textAbstract:
Larval dispersal is a key process determining population connectivity, metapopulation dynamics, and community structure in benthic marine ecosystems, yet the biophysical complexity of dispersal is not well understood. In this study, we investigate the interaction between disperser phenotype and hydrodynamics on larval dispersal pathways, using a temperate reef fish species, Trachinops caudimaculatus . We assessed the influence of larval traits on depth distribution and dispersal outcomes by: (i) using 24-h depth-stratified ichthyoplankton sampling, (ii) quantifying individual phenotypes using larval growth histories extracted from the sagittal otoliths of individual larvae, and (iii) simulating potential dispersal outcomes based on the empirical distribution of larval phenotypes and an advanced biological-physical ocean model. We found T. caudimaculatus larvae were vertically stratified with respect to phenotype, with high-quality phenotypes found in the bottom two depth strata, and poor-quality phenotypes found primarily at the surface. Our model showed high- and average-quality larvae experienced significantly higher local retention (more than double) and self-recruitment, and travelled shorter distances relative to poor-quality larvae. As populations are only connected when dispersers survive long enough to reproduce, determining how larval phenotype influences dispersal outcomes will be important for improving our understanding of marine population connectivity and persistence.
7
Kvile, Kristina Øie, Giovanni Romagnoni, Knut-Frode Dagestad, Øystein Langangen, and Trond Kristiansen. "Sensitivity of modelled North Sea cod larvae transport to vertical behaviour, ocean model resolution and interannual variation in ocean dynamics." ICES Journal of Marine Science 75, no. 7 (2018): 2413–24. http://dx.doi.org/10.1093/icesjms/fsy039.
Full textAbstract:
Abstract Transport with ocean currents affects the spatial distribution and survival of fish eggs and larvae and thereby population connectivity. Biophysical models are commonly used to understand these dynamics. Advancements such as implementing vertical swimming behaviour and higher resolution ocean circulation models are known to improve model performance, however, the relative importance of vertical behaviour vs. ocean model resolution is elusive. Here, we use North Sea cod (Gadus morhua) as a case study to assess how vertical movement, ocean model resolution and interannual variation in ocean dynamics influence drift patterns and population connectivity. We couple a fine (1.6 km, 3 h) and coarser (4 km, 24 h) ocean model to an individual-based model for cod eggs and larvae, and compare simulations with and without vertical movement of eggs and larvae. The results are moderately influenced by vertical movement and ocean model resolution but differ substantially between years. While ocean model resolution is consistently more influential than vertical movement, the effect of vertical movement strongly depends on the spatiotemporal scale of the analyses. This study highlights which aspects of biophysical modelling of connectivity that most critically affect the results, allowing better investing computational resources and proposing goal-based guidelines for future studies.
8
Crocetta, Fabio, Luigi Caputi, Sofia Paz-Sedano, Valentina Tanduo, Angelo Vazzana, and Marco Oliverio. "High genetic connectivity in a gastropod with long-lived planktonic larvae." Journal of Molluscan Studies 86, no. 1 (2019): 42–55. http://dx.doi.org/10.1093/mollus/eyz032.
Full textAbstract:
Abstract Genetic connectivity plays a crucial role in shaping the geographic structure of species. Our aim in this study was to explore the pattern of genetic connectivity in Bursa scrobilator, an iconic marine caenogastropod with long-lived pelagic larvae. Our study was based on the analysis of DNA sequence data for the 658-bp barcoding fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene. This is the largest DNA sequence dataset assembled to date for B. scrobilator. These data confirm that the two recently described subspecies B. scrobilator scrobilator (Linnaeus, 1758), from the Mediterranean and Macaronesia, and B. s. coriacea (Reeve, 1844), from West Africa, constitute two evolutionarily significant units (ESUs). We found that for the nominal subspecies, the variation in morphology (shell, radula and gross anatomy) and DNA sequences was not geographically structured, and this agrees with what we would expect in a species with high connectivity at the larval stage. The divergence between the two subspecies cannot be easily explained by isolation by distance, and we would argue that one or more extrinsic factors may have played a role in isolating the two ESUs and maintaining that isolation.
9
Bradbury, I. R., S. E. Campana, and P. Bentzen. "Low genetic connectivity in an estuarine fish with pelagic larvae." Canadian Journal of Fisheries and Aquatic Sciences 65, no. 2 (2008): 147–58. http://dx.doi.org/10.1139/f07-154.
Full textAbstract:
We evaluated the spatial scale of metapopulation structure and genetic connectivity in rainbow smelt, Osmerus mordax, using eight microsatellite loci at 22 spawning locations throughout Newfoundland and Labrador. Consistent with low gene flow and limited dispersal, significant genetic structuring (FST ≈ 0.11) was present at small spatial scales (<200 km). Moreover, strong isolation by distance (IBD, P < 0.001, r2 = 0.47) was observed, which was linear at small scales and nonlinear at large distances (>200 km). We hypothesized that despite high dispersal potential associated with a pelagic larval stage, behaviours restricting gene flow may result in structuring at the estuary scale. Multidimensional scaling and neighbour-joining of multilocus genotypes indicate some bay-scale associations. However, a comparison of FST values and IBD residuals at both estuary and bay scales indicated low structure within and elevated structure among estuaries. Estuarine structuring was further supported by the presence of significant small-scale IBD within several coastal embayments (50–100 km), as well as Bayesian clustering consistent with estuarine-scale independence. Finally, estimates of dispersal based on the IBD relationship are consistent with local estuarine recruitment (<1.5 km·generation–1). We conclude that the unexpectedly high genetic structure observed is consistent with behavioral influences reducing dispersal, supporting previous work implicating active larval retention.
10
Couton, Louise, Alex S. Mauss, Temur Yunusov, Soeren Diegelmann, Jan Felix Evers, and Matthias Landgraf. "Development of Connectivity in a Motoneuronal Network in Drosophila Larvae." Current Biology 25, no. 5 (2015): 568–76. http://dx.doi.org/10.1016/j.cub.2014.12.056.
Full text
11
Betzel, Richard F. "Organizing principles of whole-brain functional connectivity in zebrafish larvae." Network Neuroscience 4, no. 1 (2020): 234–56. http://dx.doi.org/10.1162/netn_a_00121.
Full textAbstract:
Network science has begun to reveal the fundamental principles by which large-scale brain networks are organized, including geometric constraints, a balance between segregative and integrative features, and functionally flexible brain areas. However, it remains unknown whether whole-brain networks imaged at the cellular level are organized according to similar principles. Here, we analyze whole-brain functional networks reconstructed from calcium imaging data recorded in larval zebrafish. Our analyses reveal that functional connections are distance-dependent and that networks exhibit hierarchical modular structure and hubs that span module boundaries. We go on to show that spontaneous network structure places constraints on stimulus-evoked reconfigurations of connections and that networks are highly consistent across individuals. Our analyses reveal basic organizing principles of whole-brain functional brain networks at the mesoscale. Our overarching methodological framework provides a blueprint for studying correlated activity at the cellular level using a low-dimensional network representation. Our work forms a conceptual bridge between macro- and mesoscale network neuroscience and opens myriad paths for future studies to investigate network structure of nervous systems at the cellular level.
12
Quinn, Brady K., Joël Chassé, and Rémy Rochette. "Potential connectivity among American lobster fisheries as a result of larval drift across the species’ range in eastern North America." Canadian Journal of Fisheries and Aquatic Sciences 74, no. 10 (2017): 1549–63. http://dx.doi.org/10.1139/cjfas-2016-0416.
Full textAbstract:
We used a biophysical model to estimate for the first time the effect of larval drift on potential connectivity among American lobster (Homarus americanus) fisheries management areas over the geographic range of the species. The model predicted drift of larvae over distances of 50–805 km (mean = 129 km), which connected many management areas and caused marked spatial heterogeneity in retention and self-seeding versus export and import of larvae by different fisheries areas. Including mortality functions in the model resulted in less drift and settlement and had complex effects on the amount, but not the incidence, of potential connectivity among fisheries. The model’s predictions received support from comparison of predicted settlement to landings 6 or 7 years later in some, but not all, parts of the model domain. Although improvements are still needed to capture larval behaviours and spatial variability in larval release and mortality across the species’ range, this information is important to lobster fisheries management because the amount and direction of connectivity among fisheries can inform cooperative management strategies to sustain interconnected fisheries.
13
Jessopp, M. J. "The quick and the dead: larval mortality due to turbulent tidal transport." Journal of the Marine Biological Association of the United Kingdom 87, no. 3 (2007): 675–80. http://dx.doi.org/10.1017/s0025315407055580.
Full textAbstract:
Marine populations are typically connected over greater spatial scales than their terrestrial counterparts due to many species having a highly dispersive, planktonic larval phase. However, high levels of larval mortality in the plankton may reduce connectivity between populations. The effect of turbulence on larval mortality was investigated under natural conditions in a field experiment. Larvae were collected before and after being subjected to turbulent tidal flow from a marine reserve, with differential mortality being observed between taxa. Thin-shelled veligers of gastropods and bivalves showed significantly increased mortality, while barnacle nauplii and cyprids, bryozoan cyphonaute larvae and polychaete trochophores showed no effect of turbulent tidal transport. Where appropriate, marine reserve design should account for the reduced connectivity between populations associated with turbulent tidal transport between reserve and adjacent areas.
14
Ziegler, Amanda F., Lisa Hahn-Woernle, Brian Powell, and Craig R. Smith. "Larval Dispersal Modeling Suggests Limited Ecological Connectivity Between Fjords on the West Antarctic Peninsula." Integrative and Comparative Biology 60, no. 6 (2020): 1369–85. http://dx.doi.org/10.1093/icb/icaa094.
Full textAbstract:
Synopsis Larval dispersal is a key process for community assembly and population maintenance in the marine environment, yet it is extremely difficult to measure at ecologically relevant spatio-temporal scales. We used a high-resolution hydrodynamic model and particle-tracking model to explore the dispersal of simulated larvae in a hydrographically complex region of fjords on the West Antarctic Peninsula. Modeled larvae represented two end members of dispersal potential observed in Antarctic benthos resulting from differing developmental periods and swimming behavior. For simulations of low dispersing larvae (pre-competency period = 8 days, settlement period = 15 days, swimming downward) self-recruitment within fjords was important, with no larval settlement occurring in adjacent fjords &lt;50 km apart. For simulations of highly dispersing organisms (pre-competency period = 35–120 days, settlement period = 30–115 days, no swimming behavior), dispersal between fjords occurred when larvae were in the water column for at least 35 days, but settlement was rarely successful even for larvae spending up to 150 days in the plankton. The lack of ecological connectivity between fjords within a single spawning event suggests that these fjords harbor ecologically distinct populations in which self-recruitment may maintain populations, and genetic connectivity between fjords is likely achieved through stepping-stone dispersal. Export of larvae from natal fjord populations to the broader shelf region (&gt;100 km distance) occurred within surface layers (&lt;100 m depth) and was enhanced by episodic katabatic wind events that may be common in glaciomarine fjords worldwide.
15
Goodwin, Jacob D., Daphne M. Munroe, Zafer Defne, Neil K. Ganju, and James Vasslides. "Estimating Connectivity of Hard Clam (Mercenaria mercenaria) and Eastern Oyster (Crassostrea virginica) Larvae in Barnegat Bay." Journal of Marine Science and Engineering 7, no. 6 (2019): 167. http://dx.doi.org/10.3390/jmse7060167.
Full textAbstract:
Many marine organisms have a well-known adult sessile stage. Unfortunately, our lack of knowledge regarding their larval transient stage hinders our understanding of their basic ecology and connectivity. Larvae can have swimming behavior that influences their transport within the marine environment. Understanding the larval stage provides insight into population connectivity that can help strategically identify areas for restoration. Current techniques for understanding the larval stage include modeling that combines particle attributes (e.g., larval behavior) with physical processes of water movement to contribute to our understanding of connectivity trends. This study builds on those methods by using a previously developed retention clock matrix (RCM) to illustrate time dependent connectivity of two species of shellfish between areas and over a range of larval durations. The RCM was previously used on physical parameters but we expand the concept by applying it to biology. A new metric, difference RCM (DRCM), is introduced to quantify changes in connectivity under different scenarios. Broad spatial trends were similar for all behavior types with a general south to north progression of particles. The DRCMs illustrate differences between neutral particles and those with behavior in northern regions where stratification was higher, indicating that larval behavior influenced transport. Based on these findings, particle behavior led to small differences (north to south movement) in transport patterns in areas with higher salinity gradients (the northern part of the system) compared to neutral particles. Overall, the dominant direction for particle movement was from south to north, which at times was enhanced by winds from the south. Clam and oyster restoration in the southern portion of Barnegat Bay could serve as a larval supply for populations in the north. These model results show that coupled hydrodynamic and particle tracking models have implications for fisheries management and restoration activities.
16
Feng, Ming, Nick Caputi, James Penn, et al. "Ocean circulation, Stokes drift, and connectivity of western rock lobster (Panulirus cygnus) population." Canadian Journal of Fisheries and Aquatic Sciences 68, no. 7 (2011): 1182–96. http://dx.doi.org/10.1139/f2011-065.
Full textAbstract:
An individual-based model, incorporating outputs of a data-assimilating hydrodynamic model, was developed to investigate the role of ocean circulation in the recruitment processes of western rock lobster ( Panulirus cygnus ) during its 9- to 11-month larval phase off the west coast of Australia. During austral summer, strong northward alongshore winds aid the offshore movement of early-stage model larvae from midshelf hatching sites into open ocean; during austral winter, eastward flows that feed the enhanced Leeuwin Current facilitate onshore movement of late-stage larvae towards nearshore habitats. Stokes drift induced by swells from the Southern Ocean is critical to retain larvae off the west coast. Diurnal migration and temperature-dependent growth are also important. Model larvae hatched in late spring – early summer grow faster because of longer exposure to warm summer temperature, which allows them to be transported towards the coast by the strong onshore flows in winter and reduces their natural mortality. Preliminary source–sink relationship indicates that the population was well mixed off the coast, with higher likelihood of settlement success from hatching sites in the north, mostly due to higher surface temperature. Weighted with the breeding stock distribution, the area between 27.5°S and 29.5°S, including the Abrolhos Islands, is the most important hatching area to the success of settlement.
17
Calò, Antonio, Fabiana C. Félix-Hackradt, Jessica Garcia, et al. "A review of methods to assess connectivity and dispersal between fish populations in the Mediterranean Sea." Advances in Oceanography and Limnology 4, no. 2 (2013): 150. http://dx.doi.org/10.4081/aiol.2013.5342.
Full textAbstract:
Fish populations are linked to each other via dispersal of individuals as eggs, larvae, juveniles or adults. The understanding of this process, known as connectivity, has a pivotal role for the management of overexploited fish stocks and the development of accurate conservation strategies. Knowledge on connectivity and fish movements is considered fundamental toward the correct design of marine protected area (MPA) networks for the achievement of the benefits of protection. Connectivity patterns are still largely unknown worldwide. A general lack of knowledge is particularly evident for the Mediterranean Sea where few studies dealing with this topic have been carried out and some methods, currently available for assessing connectivity, have not been used yet. In this review we present the methods used for studying connectivity patterns and fish movements at different life history stages and the main results achieved until now in the Mediterranean Sea. We encompass the pros and cons of each method, and conclude with future perspectives on the use of these methodologies in the Mediterranean context.
18
Compaire, Jesus C., Paula Pérez‐Brunius, Sylvia Patricia Adelheid Jiménez‐Rosenberg, Javier Rodríguez Outerelo, Laura del Pilar Echeverri García, and Sharon Z. Herzka. "Connectivity of coastal and neritic fish larvae to the deep waters." Limnology and Oceanography 66, no. 6 (2021): 2423–41. http://dx.doi.org/10.1002/lno.11762.
Full text
19
Bell, JJ. "Similarity in connectivity patterns for two gastropod species lacking pelagic larvae." Marine Ecology Progress Series 357 (April 7, 2008): 185–94. http://dx.doi.org/10.3354/meps07301.
Full text
20
Ospina-Alvarez, A., S. de Juan, J. Alós, et al. "MPA network design based on graph theory and emergent properties of larval dispersal." Marine Ecology Progress Series 650 (September 17, 2020): 309–26. http://dx.doi.org/10.3354/meps13399.
Full textAbstract:
Despite the recognised effectiveness of networks of marine protected areas (MPAs) as a biodiversity conservation instrument, MPA network design frequently disregards the importance of connectivity patterns. In the case of sedentary marine populations, connectivity stems not only from the stochastic nature of the physical environment that affects dispersal of early life stages, but also from the spawning stock attributes that affect reproductive output (e.g. passive eggs and larvae) and survivorship. Early life stages are virtually impossible to track in the ocean. Therefore, numerical ocean current simulations coupled with egg and larval Lagrangian transport models remain the most common approach for the assessment of marine larval connectivity. Inferred larval connectivity may differ depending on the type of connectivity considered; consequently, the prioritisation of sites for the conservation of marine populations might also differ. Here, we introduce a framework for evaluating and designing MPA networks based on the identification of connectivity hotspots using graph theoretic analysis. As a case study, we used a network of open-access areas and MPAs off Mallorca Island (Spain), and tested its effectiveness for the protection of the painted comber Serranus scriba. Outputs from network analysis were used to (1) identify critical areas for improving overall larval connectivity, (2) assess the impact of species’ biological parameters in network connectivity and (3) explore alternative MPA configurations to improve average network connectivity. Results demonstrate the potential of graph theory to identify non-trivial egg/larval dispersal patterns and emerging collective properties of the MPA network, which are relevant for increasing protection efficiency.
21
Johnstone, Carolina, Montse Pérez, Estrella Malca, et al. "Genetic connectivity between Atlantic bluefin tuna larvae spawned in the Gulf of Mexico and in the Mediterranean Sea." PeerJ 9 (June 14, 2021): e11568. http://dx.doi.org/10.7717/peerj.11568.
Full textAbstract:
The highly migratory Atlantic bluefin tuna (ABFT) is currently managed as two distinct stocks, in accordance with natal homing behavior and population structuring despite the absence of barriers to gene flow. Larval fish are valuable biological material for tuna molecular ecology. However, they have hardly been used to decipher the ABFT population structure, although providing the genetic signal from successful breeders. For the first time, cooperative field collection of tuna larvae during 2014 in the main spawning area for each stock, the Gulf of Mexico (GOM) and the Mediterranean Sea (MED), enabled us to assess the ABFT genetic structure in a precise temporal and spatial frame exclusively through larvae. Partitioning of genetic diversity at nuclear microsatellite loci and in the mitochondrial control region in larvae spawned contemporarily resulted in low significant fixation indices supporting connectivity between spawners in the main reproduction area for each population. No structuring was detected within the GOM after segregating nuclear diversity in larvae spawned in two hydrographically distinct regions, the eastern GOM (eGOM) and the western GOM (wGOM), with the larvae from eGOM being more similar to those collected in the MED than the larvae from wGOM. We performed clustering of genetically characterized ABFT larvae through Bayesian analysis and by Discriminant Analysis of Principal Components (DAPC) supporting the existence of favorable areas for mixing of ABFT spawners from Western and Eastern stocks, leading to gene flow and apparent connectivity between weakly structured populations. Our findings suggest that the eastern GOM is more prone for the mixing of breeders from the two ABFT populations. Conservation of this valuable resource exploited for centuries calls for intensification of tuna ichthyoplankton research and standardization of genetic tools for monitoring population dynamics.
22
Eble, Jeff A., Luiz A. Rocha, Matthew T. Craig, and Brian W. Bowen. "Not All Larvae Stay Close to Home: Insights into Marine Population Connectivity with a Focus on the Brown Surgeonfish (Acanthurus nigrofuscus)." Journal of Marine Biology 2011 (2011): 1–12. http://dx.doi.org/10.1155/2011/518516.
Full textAbstract:
Recent reports of localized larval recruitment in predominately small-range fishes are countered by studies that show high genetic connectivity across large oceanic distances. This discrepancy may result from the different timescales over which genetic and demographic processes operate or rather may indicate regular long-distance dispersal in some species. Here, we contribute an analysis of mtDNA cytochromebdiversity in the widely distributed Brown Surgeonfish (Acanthurus nigrofuscus;N=560), which revealed significant genetic structure only at the extremes of the range (ΦCT=0.452;P<.001). Collections from Hawaii to the Eastern Indian Ocean comprise one large, undifferentiated population. This pattern of limited genetic subdivision across reefs of the central Indo-Pacific has been observed in a number of large-range reef fishes. Conversely, small-range fishes are often deeply structured over the same area. These findings demonstrate population connectivity differences among species at biogeographic and evolutionary timescales, which likely translates into differences in dispersal ability at ecological and demographic timescales. While interspecific differences in population connectivity complicate the design of management strategies, the integration of multiscale connectivity patterns into marine resource planning will help ensure long-term ecosystem stability by preserving functionally diverse communities.
23
Cantrell, Danielle, Ramón Filgueira, Crawford W. Revie, et al. "The relevance of larval biology on spatiotemporal patterns of pathogen connectivity among open-marine salmon farms." Canadian Journal of Fisheries and Aquatic Sciences 77, no. 3 (2020): 505–19. http://dx.doi.org/10.1139/cjfas-2019-0040.
Full textAbstract:
Warming waters are changing marine pathogen dispersal patterns and infectivity worldwide. Coupled biological–physical modelling has been used in many systems to determine the connectivity of metapopulations via infectious disease particles. Here we model the connectivity of sea lice larvae (Lepeophtheirus salmonis) among salmon farms in the Broughton Archipelago, British Columbia, Canada, using a coupled biological–physical model. The physical model simulated pathogen dispersal, while the biological component influenced the survival and developmental rates of the sea lice. Model results predicted high temporal variability in connectivity strength among farms, an emergent effect from the interacting parts of the simulation (dispersion versus survival and development). Drivers of temporal variability were disentangled using generalized additive modeling, which revealed the variability was most strongly impacted by the spring freshet, which can act as a natural aid for sea lice control in the Broughton Archipelago. Our results suggest that farm management strategies can benefit by accounting for short-term spikes in regional pathogen connectivity among farms. Additionally, future scenarios of a warming climate with reduced snowpack can make sea lice control more challenging.
24
Fontoura, Luisa, Stephanie D’Agata, Majambo Gamoyo, et al. "Protecting connectivity promotes successful biodiversity and fisheries conservation." Science 375, no. 6578 (2022): 336–40. http://dx.doi.org/10.1126/science.abg4351.
Full textAbstract:
The global decline of coral reefs has led to calls for strategies that reconcile biodiversity conservation and fisheries benefits. Still, considerable gaps in our understanding of the spatial ecology of ecosystem services remain. We combined spatial information on larval dispersal networks and estimates of human pressure to test the importance of connectivity for ecosystem service provision. We found that reefs receiving larvae from highly connected dispersal corridors were associated with high fish species richness. Generally, larval “sinks” contained twice as much fish biomass as “sources” and exhibited greater resilience to human pressure when protected. Despite their potential to support biodiversity persistence and sustainable fisheries, up to 70% of important dispersal corridors, sinks, and source reefs remain unprotected, emphasizing the need for increased protection of networks of well-connected reefs.
25
Landeira, José M., Timothée Brochier, Evan Mason, Fernando Lozano-Soldevilla, Santiago Hernández-León, and Eric D. Barton. "Transport pathways of decapod larvae under intense mesoscale activity in the Canary-African coastal transition zone: implications for population connectivity." Scientia Marina 81, no. 3 (2017): 299. http://dx.doi.org/10.3989/scimar.04599.06a.
Full textAbstract:
We investigate the transport dynamics of decapod larvae in the Canary-African coastal transition zone (C-ACTZ), where larval assemblages are poorly known. In August 1999, during the FAX99 cruise, the waters downstream of the Canary Island archipelago displayed intense mesoscale activity, with numerous cyclonic and anticyclonic eddies as well as upwelling filaments. Our results illustrate a close relationship between these mesoscale oceanographic structures and the distribution of decapod larvae, using both field observations and Lagrangian transport modelling. Analysis of plankton samples shows that larvae of pelagic species were excluded from filament waters, whereas larvae of neritic species were heterogeneously distributed, suggesting that the C-ACTZ is a mixing area where larvae originating from both the Canary Islands and the African coast may be present at the same time. This finding was supported by the simulations, which suggested that the larvae collected in the offshore waters south of Gran Canaria came mainly from the African population (between Cape Bojador and Cape Juby) during early August, whereas during the second half of August the targeted area was dominated by larvae released from Fuerteventura populations. Our observations introduce new insights into our understanding of marine population connectivity, the dispersal pathways of the terrestrial biota, and general biogeography in the region.
26
Monroy, Pedro, Vincent Rossi, Enrico Ser-Giacomi, Cristóbal López, and Emilio Hernández-García. "Sensitivity and robustness of larval connectivity diagnostics obtained from Lagrangian Flow Networks." ICES Journal of Marine Science 74, no. 6 (2017): 1763–79. http://dx.doi.org/10.1093/icesjms/fsw235.
Full textAbstract:
Abstract Lagrangian Flow Network (LFN) is a modelling framework in which ocean sub-areas are represented as nodes in a network interconnected by links representing transport of propagules (eggs and larvae) by currents. We asses the sensitivity and robustness of four LFN-derived connectivity metrics measuring retention and exchange. The most relevant parameters are tested over large ranges and a wide region with contrasting hydrodynamics: density of released particles, node size (spatial scale of discretization), Pelagic Larval Duration (PLD) and spawning modality. We find a minimum density of released particles that guarantees reliable values for most of the metrics examined. We also find that node size has a nontrivial influence on them. Connectivity estimates for long PLDs are more robust against biological uncertainties (PLD and spawning date) than for short PLDs. For mass-spawners releasing propagules over short periods (≈ 2-10 days), daily release must be simulated to properly consider connectivity fluctuations due to variable currents. In contrast, average connectivity estimates for species that spawn repeatedly over longer durations (few weeks to few months) remain robust even using longer periodicity (5-10 days). Our results have implications to design connectivity experiments with particle-tracking models and to evaluate the reliability of their results.
27
Kaplan, David M., Marion Cuif, Cécile Fauvelot, et al. "Uncertainty in empirical estimates of marine larval connectivity." ICES Journal of Marine Science 74, no. 6 (2016): 1723–34. http://dx.doi.org/10.1093/icesjms/fsw182.
Full textAbstract:
Abstract Despite major advances in our capacity to measure marine larval connectivity (i.e. the pattern of transport of marine larvae from spawning to settlement sites) and the importance of these measurements for ecological and management questions, uncertainty in experimental estimates of marine larval connectivity has been given little attention. We review potential uncertainty sources in empirical larval connectivity studies and develop Bayesian statistical methods for estimating these uncertainties based on standard techniques in the mark-recapture and genetics literature. These methods are implemented in an existing R package for working with connectivity data, ConnMatTools, and applied to a number of published connectivity estimates. We find that the small sample size of collected settlers at destination sites is a dominant source of uncertainty in connectivity estimates in many published results. For example, widths of 95% CIs for relative connectivity, the value of which is necessarily between 0 and 1, exceeded 0.5 for many published connectivity results, complicating using individual results to conclude that marine populations are relatively closed or open. This “small sample size” uncertainty is significant even for studies with near-exhaustive sampling of spawners and settlers. Though largely ignored in the literature, the magnitude of this uncertainty is straightforward to assess. Better accountability of this and other uncertainties is needed in the future so that marine larval connectivity studies can fulfill their promises of providing important ecological insights and informing management questions (e.g. related to marine protected area network design, and stock structure of exploited organisms). In addition to using the statistical methods developed here, future studies should consistently evaluate and report a small number of critical factors, such as the exhaustivity of spawner and settler sampling, and the mating structure of target species in genetic studies.
28
Jordan, Steve, Brian K. Hand, Scott Hotaling, et al. "Genomic data reveal similar genetic differentiation in aquifer species with different dispersal capabilities and life histories." Biological Journal of the Linnean Society 129, no. 2 (2019): 315–22. http://dx.doi.org/10.1093/biolinnean/blz173.
Full textAbstract:
Abstract Little is known about the life histories, genetic structure and population connectivity of shallow groundwater organisms. We used next-generation sequencing (RAD-seq) to analyse population genomic structure in two aquifer species: Paraperla frontalis (Banks, 1902), a stonefly with groundwater larvae and aerial (winged) adults; and Stygobromus sp., a groundwater-obligate amphipod. We found similar genetic differentiation in each species between floodplains separated by ~70 river km in the Flathead River basin of north-west Montana, USA. Given that Stygobromus lacks the above-ground life stage of P. frontalis, our findings suggest that connectivity and the magnitude of genetic structure cannot be definitively assumed from life history differences.
29
Gancel, HN, RH Carmichael, J. Du, and K. Park. "Use of settlement patterns and geochemical tagging to test population connectivity of eastern oysters Crassostrea virginica." Marine Ecology Progress Series 673 (September 2, 2021): 85–105. http://dx.doi.org/10.3354/meps13796.
Full textAbstract:
Freshwater-dominated estuaries experience large fluctuations in their physical and chemical environments which may influence larval dispersal, settlement, and connectivity of populations with pelagic larval stages. We used settlement patterns and natural tagging along with numerical hydrodynamic model results to assess settlement and connectivity among oysters across the freshwater-dominated Mobile Bay-eastern Mississippi Sound (MB-EMS) system. Specifically, we (1) tested how freshwater inputs and associated environmental attributes influenced settlement patterns during high and low discharge conditions in 2014 and 2016, respectively, and (2) analyzed trace element (TE) ratios incorporated into multiple shell types (larval and settled shell of spat and adult shells) to determine if shells collected in situ incorporate temporally stable site-specific signatures. We also assessed if TE ratios compared between adult (TE natal signature proxy) and larval shells could infer connectivity. Larval settlement was 4× higher during low discharge than during high discharge when oyster larvae only settled in higher salinity regions (EMS). Spat and adult shells incorporated site-specific TE ratios that varied from weeks to months. Connectivity results (May-June 2016 only) suggest that EMS is an important larval source to EMS and lower MB. While we were able to infer probable connectivity patterns using adult and larval shells, more study is needed to assess the utility of adult shells as proxies for natal-location TE signatures. Results provide a baseline for measuring future larval connectivity and adult distribution changes in the MB-EMS system. Biological and geochemical data demonstrate the potential to identify environmental attributes that spatiotemporally mediate settlement and connectivity in dynamic systems.
30
Rudorff, Camila Aguirre Góes, João Antônio Lorenzzetti, Douglas F. M. Gherardi, and Jorge Eduardo Lins-Oliveira. "Application of remote sensing to the study of the pelagic spiny lobster larval transport in the Tropical Atlantic." Brazilian Journal of Oceanography 57, no. 1 (2009): 7–16. http://dx.doi.org/10.1590/s1679-87592009000100002.
Full textAbstract:
The connectivity of marine populations via larval dispersal is crucial for the maintenance of fisheries production and biodiversity. Because larval dispersion takes place on different spatial scales, global operational satellite data can be successfully used to investigate the connectivity of marine populations on different spatial and temporal scales. In fact, satellite data have long been used for the study of the large and mesoscale biological processes associated with ocean dynamics. This paper presents simulations of spiny lobster larvae transport in the Tropical Atlantic using the geostrophic currents, generated by altimetry that feeds an advection/diffusion model. Simulations were conducted over the Tropical Atlantic (20ºN to 15ºS), considering four larvae release areas: the Cape Verde Archipelago, the Ivory Coast, Ascension Island and Fernando de Noronha Archipelago. We used mean geostrophic current (MGC) calculated from 2001 to 2005 to represent the mean circulation of the Tropical Atlantic. We also ran the model for the El Niño geostrophic current regime (ENGC) using part of the MGC data, representing the El Niño 2002/2003 event. Results suggest that the intensification of the mesoscale ocean processes associated with El Niño events promotes the connectivity between populations, increasing the chances of a genetic flux among different stocks. We concluded that the altimetry geostrophic current data together with a relatively simple advection/diffusion model can provide useful information about the physical dynamics necessary to conduct studies on larval dispersion.
31
Chan, Wan Wen Rochelle, Ywee Chieh Tay, Hui Ping Ang, et al. "Reproduction in Urbanised Coastal Waters: Shallow-Water Sea Anemones (Entacmaea quadricolor and Stichodactyla haddoni) Maintain High Genetic Diversity and Panmixia." Diversity 12, no. 12 (2020): 467. http://dx.doi.org/10.3390/d12120467.
Full textAbstract:
Sea anemones are sedentary marine animals that tend to disperse via planktonic larvae and are predicted to have high population connectivity in undisturbed habitats. We test whether two sea anemone species living in two different tidal zones of a highly disturbed marine environment can maintain high genetic connectivity. More than 1000 loci with single-nucleotide polymorphisms (SNPs) were obtained with double-digest RADseq for 81 Stichodactyla haddoni and 99 Entacmaea quadricolor individuals to test for population genetic structure. We find evidence that both species predominantly propagate via sexual reproduction, and asexual reproduction is limited. We observe panmixia that indicates the absence of effective dispersal barriers for these species living in a highly anthropogenically disturbed environment. This is positive news for both species that are also found in the aquarium trade. More fundamentally, our results suggest that inhabiting different parts of a shallow reef may not affect a species’ population connectivity nor favour asexual reproduction.
32
Abesamis, Rene. "Connectivity of Coral Reefs and other Nearshore Habitats: Implications for Marine Resource Management in the Philippines." Transactions of the National Academy of Science and Technology 40, no. 2018 (2022): 1–13. http://dx.doi.org/10.57043/transnastphl.2018.1084.
Full textAbstract:
Marine protected areas (MPAs) have become a mainstay of marine resource management in the Philippines in the past three decades and there is growing advocacy to implement MPA networks — systems of MPAs that effectively protect sufficient proportions of the populations of targeted species. MPA networks aim to reduce fishery-induced mortality of targeted species during critical life stages. Thus, a primary consideration of protecting populations using MPA networks is connectivity — the linking of local populations through the movement of adults or juveniles and the dispersal of larvae. This paper discusses the implications of emerging new knowledge on connectivity for MPA-centric marine resource management in the Philippines, with focus on demersal fishes inhabiting coral reefs, seagrass beds, algal beds, mangroves, and other vital nearshore habitats. The major successes and shortcomings of implementing MPAs are summarized and the evidence for MPA networks improving fisheries via connectivity is assessed. Highlighted are five major challenges for managing marine resources using MPA networks.
33
Godfrey, Paul C., Angela H. Arthington, Richard G. Pearson, Fazlul Karim, and Jim Wallace. "Fish larvae and recruitment patterns in floodplain lagoons of the Australian Wet Tropics." Marine and Freshwater Research 68, no. 5 (2017): 964. http://dx.doi.org/10.1071/mf15421.
Full textAbstract:
Floodplain lagoons in the Queensland Wet Tropics bioregion, Australia, are important and threatened habitats for fish. As part of studies to assess their ecological condition and functions, we examined patterns of occurrence of fish larvae, juveniles and adults in 10 permanent lagoons on the Tully–Murray floodplain. Lagoons contained early life-history stages of 15 of the 21 native species present, including 11 species that complete their life cycle in fresh waters and 4 that require access to saline habitats for larval development. Lagoon connectivity to the rivers, distance from the coast and flood dynamics influenced temporal variation in fish abundance, population size structures and recruitment patterns. This study and the literature show that wet, post-wet and dry-season habitats are utilised by small opportunists (e.g. Melanotaenia splendida), an equilibrium species (Glossamia aprion) and larger periodic strategists (neosilurid catfishes). Maintenance of natural seasonal patterns of flow and connectivity, and active protection of permanent floodplain lagoons from riparian and land-use disturbance, will be essential if their roles in fish recruitment are to be sustained.
34
Doropoulos, Christopher, and George Roff. "Coloring coral larvae allows tracking of local dispersal and settlement." PLOS Biology 20, no. 12 (2022): e3001907. http://dx.doi.org/10.1371/journal.pbio.3001907.
Full textAbstract:
Quantifying patterns of dispersal and settlement in marine benthic invertebrates is challenging, largely due the complexity of life history traits, small sizes of larvae (<1 mm), and potential for large-scale dispersal (>100 km) in the marine environment. Here, we develop a novel method that allows for immediate differentiation and visual tracking of large numbers of coral larvae (106 to 109) from dispersal to settlement. Neutral red and Nile blue stains were extremely effective in coloring larvae, with minimal impacts on survival and settlement following optimization of incubation times and stain concentrations. Field validation to wild-captured larvae from the Great Barrier Reef demonstrates the efficacy of staining across diverse taxa. The method provides a simple, rapid (<60 minutes), low-cost (approximately USD$1 per 105 larva) tool to color coral larvae that facilitates a wide range of de novo laboratory and field studies of larval behavior and ecology with potential applications for conservation planning and understanding patterns of connectivity.
35
Rodriguez-Perez, Ana, Mark A. James, and William G. Sanderson. "A small step or a giant leap: Accounting for settlement delay and dispersal in restoration planning." PLOS ONE 16, no. 8 (2021): e0256369. http://dx.doi.org/10.1371/journal.pone.0256369.
Full textAbstract:
Understanding larval duration and hence dispersal potential of the European oyster Ostrea edulis is crucial to inform restoration strategies. Laval duration has an obligatory period of maturity to pediveliger (when larvae are ready to settle), but also an unknown period until metamorphosis is triggered by a settlement cue. The extent to which larvae can prolong the pediveliger period and delay metamorphosis has not been studied. Here we show that O. edulis larvae can delay metamorphosis for a period of 11 days, while retaining the capability to settle in high proportions when presented with a suitable settlement cue. O. edulis larvae are likely to be able to delay metamorphosis even further, since 80% of larvae in the control treatment were still alive when the experiment was terminated at day 14. The results indicate the ability of O. edulis larvae to more than double pelagic duration and probably further delay metamorphosis. We discuss these findings in the context of larval mortality, and the importance of O. edulis’ larval settlement requirements for dispersal potential, recruitment success and connectivity of restoration sites.
36
Huwer, B., H. H. Hinrichsen, K. Hüssy, and M. Eero. "Connectivity of larval cod in the transition area between North Sea and Baltic Sea and potential implications for fisheries management." ICES Journal of Marine Science 73, no. 7 (2016): 1815–24. http://dx.doi.org/10.1093/icesjms/fsw043.
Full textAbstract:
Abstract Connectivity of pelagic, early life stages via transport by ocean currents may affect survival chances of offspring, recruitment success, and mixing of stocks across management units. Based on drift model studies, transport patterns of particles representing exogenously feeding cod larvae in the transition area between North Sea and Baltic were investigated to (i) determine long-term trends and variability in advective transport of larvae from spawning grounds to juvenile nursery areas, (ii) estimate the degree of exchange between different management areas, and (iii) compare the results with spatial distributions of juvenile cod. The transport of particles showed considerable intra- and interannual variability, but also some general patterns of retention within and dispersion to different management areas. Good spatial overlap of particle end positions, representing potential juvenile settlement areas, with observed distributions of juveniles in bottom trawl surveys suggests that the drift simulations provide reasonable estimates of early life stage connectivity between cod populations in the investigated areas. High exchange rates of particles between management areas of up to ca. 70% suggest that cod populations in the investigated areas are demographically correlated. Results are discussed in relation to their relevance for stock structure, fish stock assessment, and management.
37
Nishimoto, Mary M., Rachel D. Simons, and Milton S. Love. "Offshore oil production platforms as potential sources of larvae to coastal shelf regions off southern California." Bulletin of Marine Science 95, no. 4 (2019): 535–58. http://dx.doi.org/10.5343/bms.2019.0033.
Full textAbstract:
A diverse assemblage of adult reef fishes and invertebrates occurs at offshore oil production platforms in the Southern California Bight (SCB). Coincident with the initiation of the decommissioning of six platforms in the SCB, the goal of this study was to examine how a platform's geographical location plays a role in its potential contribution of larval recruits to natural areas. Using a three-dimensional biophysical model, we quantified the potential connectivity of larvae, particularly relevant to reef fishes, from three offshore platforms to four coastal shelf regions where the majority of rocky settlement habitat occurs in the SCB. The regions cover the shelves of the mainland coast and islands and offshore banks in the southern SCB. The main findings indicate that (1) the potential for larval subsidies from platforms in the southern SCB to populations in the northern SCB are greater than the potential for larval subsidies from platforms in the northern SCB to the southern SCB; (2) there is greater seasonal variability of potential connectivity from platforms to the mainland shelf region of the northern SCB than to the mainland shelf region of the southern SCB or shelves around islands and banks; and (3) there is consistency across years in the relative magnitude of potential connectivity from the platforms to the four shelf regions. We conclude that a platform's function as a larval source should be considered an ecological criterion when evaluating whether a platform is to be converted to an artificial reef and implementing marine spatial planning.
38
Veliz, David, Noemi Rojas-Hernández, Pablo Fibla, Boris Dewitte, Sebastián Cornejo-Guzmán, and Carolina Parada. "High levels of connectivity over large distances in the diadematid sea urchin Centrostephanus sylviae." PLOS ONE 16, no. 11 (2021): e0259595. http://dx.doi.org/10.1371/journal.pone.0259595.
Full textAbstract:
Most benthic marine invertebrates with sedentary benthic adult phases have planktonic larvae that permit connectivity between geographically isolated populations. Planktonic larval duration and oceanographic processes are vital to connecting populations of species inhabiting remote and distant islands. In the present study, we analyzed the population genetic structure of the sea urchin Centrostephanus sylviae, which inhabits only the Juan Fernández Archipelago and the Desventuradas islands, separated by more than 800 km. For 92 individuals collected from Robinson Crusoe and Selkirk Islands (Juan Fernández Archipelago) and San Ambrosio Island (Desventuradas Islands), 7,067 single nucleotide polymorphisms (SNPs) were obtained. The results did not show a spatial genetic structure for C. sylviae; relative high migration rates were revealed between the islands. An analysis of the water circulation pattern in the area described a predominant northward water flow with periods of inverted flow, suggesting that larvae could move in both directions. Overall, this evidence suggests that C. sylviae comprises a single large population composed of individuals separated by more than 800 km.
39
Hameed, Sarah O., J. Wilson White, Seth H. Miller, Kerry J. Nickols, and Steven G. Morgan. "Inverse approach to estimating larval dispersal reveals limited population connectivity along 700 km of wave-swept open coast." Proceedings of the Royal Society B: Biological Sciences 283, no. 1833 (2016): 20160370. http://dx.doi.org/10.1098/rspb.2016.0370.
Full textAbstract:
Demographic connectivity is fundamental to the persistence and resilience of metapopulations, but our understanding of the link between reproduction and recruitment is notoriously poor in open-coast marine populations. We provide the first evidence of high local retention and limited connectivity among populations spanning 700 km along an open coast in an upwelling system. Using extensive field measurements of fecundity, population size and settlement in concert with a Bayesian inverse modelling approach, we estimated that, on average, Petrolisthes cinctipes larvae disperse only 6.9 km (±25.0 km s.d.) from natal populations, despite spending approximately six weeks in an open-coast system that was once assumed to be broadly dispersive. This estimate differed substantially from our prior dispersal estimate (153.9 km) based on currents and larval duration and behaviour, revealing the importance of employing demographic data in larval dispersal estimates. Based on this estimate, we predict that demographic connectivity occurs predominantly among neighbouring populations less than 30 km apart. Comprehensive studies of larval production, settlement and connectivity are needed to advance an understanding of the ecology and evolution of life in the sea as well as to conserve ecosystems. Our novel approach provides a tractable framework for addressing these questions for species occurring in discrete coastal populations.
40
Foley, Carolyn J., and Jeffrey D. Holland. "Do flying beetles respond to human-dominated landscapes as complex mosaics or binary patterns." Landscape Online 16 (February 5, 2010): 1–18. http://dx.doi.org/10.3097/lo.200916.
Full textAbstract:
Understanding and measuring functional connectivity for animals with habitats that have been fragmented by human activity requires that the biology and movement of the species be considered. We used least cost paths in GIS to test hypotheses regarding how different species of longhorned beetles likely connect habitats with dispersal. We predicted that there would be differences in the functional connectivity of landscapes depending on species larval niche breadth, adult feeding habits, and the potential for use of non-forest habitats. For the species with very specialized larvae, we developed a classification tree to determine areas likely to contain the appropriate species of host tree. Connectivity calculated using least cost paths did not out-perform Euclidean distances for three generalist beetles. This was also the case for the specialist beetle species when all forest was considered habitat. However, when we delineated habitat based on areas likely to support the host tree the functional connectivity incorporating least cost paths was a much better predictor than that using Euclidean distances. Generalists may respond to fragmented habitat in a binary habitat-matrix way while more specialized species may respond to a mosaic. These trends are obscured if habitat is defined by human perceptions rather than species biology.
41
Foley, Carolyn J., and Jeffrey D. Holland. "Do flying beetles respond to human-dominated landscapes as complex mosaics or binary patterns." Landscape Online 16 (February 5, 2010): 1–18. http://dx.doi.org/10.3097/lo.201016.
Full textAbstract:
Understanding and measuring functional connectivity for animals with habitats that have been fragmented by human activity requires that the biology and movement of the species be considered. We used least cost paths in GIS to test hypotheses regarding how different species of longhorned beetles likely connect habitats with dispersal. We predicted that there would be differences in the functional connectivity of landscapes depending on species larval niche breadth, adult feeding habits, and the potential for use of non-forest habitats. For the species with very specialized larvae, we developed a classification tree to determine areas likely to contain the appropriate species of host tree. Connectivity calculated using least cost paths did not out-perform Euclidean distances for three generalist beetles. This was also the case for the specialist beetle species when all forest was considered habitat. However, when we delineated habitat based on areas likely to support the host tree the functional connectivity incorporating least cost paths was a much better predictor than that using Euclidean distances. Generalists may respond to fragmented habitat in a binary habitat-matrix way while more specialized species may respond to a mosaic. These trends are obscured if habitat is defined by human perceptions rather than species biology.
42
Berenshtein, Igal, Claire B. Paris, Hezi Gildor, et al. "Auto-correlated directional swimming can enhance settlement success and connectivity in fish larvae." Journal of Theoretical Biology 439 (February 2018): 76–85. http://dx.doi.org/10.1016/j.jtbi.2017.11.009.
Full text
43
Porri, Francesca, Tembisa Jordaan, and Christopher D. McQuaid. "Does cannibalism of larvae by adults affect settlement and connectivity of mussel populations?" Estuarine, Coastal and Shelf Science 79, no. 4 (2008): 687–93. http://dx.doi.org/10.1016/j.ecss.2008.06.010.
Full text
44
Thum, A. S., B. Leisibach, N. Gendre, M. Selcho, and R. F. Stocker. "Diversity, variability, and suboesophageal connectivity of antennal lobe neurons in D. melanogaster larvae." Journal of Comparative Neurology 519, no. 17 (2011): 3415–32. http://dx.doi.org/10.1002/cne.22713.
Full text
45
Brodnik, Reed M., Michael E. Fraker, Eric J. Anderson, et al. "Larval dispersal underlies demographically important intersystem connectivity in a Great Lakes yellow perch (Perca flavescens) population." Canadian Journal of Fisheries and Aquatic Sciences 73, no. 3 (2016): 416–26. http://dx.doi.org/10.1139/cjfas-2015-0161.
Full textAbstract:
Ability to quantify connectivity among spawning subpopulations and their relative contribution of recruits to the broader population is a critical fisheries management need. By combining microsatellite and age information from larval yellow perch (Perca flavescens) collected in the Lake St. Clair – Detroit River system (SC-DRS) and western Lake Erie with a hydrodynamic backtracking approach, we quantified subpopulation structure, connectivity, and contributions of recruits to the juvenile stage in western Lake Erie during 2006–2007. After finding weak (yet stable) genetic structure between the SC-DRS and two western Lake Erie subpopulations, microsatellites also revealed measurable recruitment of SC-DRS larvae to the juvenile stage in western Lake Erie (17%–21% during 2006–2007). Consideration of precollection larval dispersal trajectories, using hydrodynamic backtracking, increased estimated contributions to 65% in 2006 and 57% in 2007. Our findings highlight the value of complementing subpopulation discrimination methods with hydrodynamic predictions of larval dispersal by revealing the SC-DRS as a source of recruits to western Lake Erie and also showing that connectivity through larval dispersal can affect the structure and dynamics of large lake fish populations.
46
Morse, Bryan L., Brady K. Quinn, Michel Comeau, and Rémy Rochette. "Stock structure and connectivity of the American lobster (Homarus americanus) in the southern Gulf of St. Lawrence: Do benthic movements matter?" Canadian Journal of Fisheries and Aquatic Sciences 75, no. 11 (2018): 2096–108. http://dx.doi.org/10.1139/cjfas-2017-0346.
Full textAbstract:
The long-range dispersal of pelagic larvae is often assumed to be the dominant force behind connectivity in the marine environment, with little consideration given to benthic movements. We analyzed data from an American lobster (Homarus americanus) tagging study (1980–1996) in the Gulf of St. Lawrence during which 37 579 adults from 14 locations were tagged and 6296 were recaptured after 1–6 years at large. The 10th percentile greatest distance moved by tagged lobsters after 1 year at large contributed to demographic connectivity between neighbouring statistical districts, fishing ports, and (in one location) management areas. Considering the incremental dispersal of lobsters after 2 versus 1 year at large, we estimated that the 10th percentile greatest benthic dispersal distances after 1, 2, and 5 years at large represented, respectively, 7%, 14%, and 35% of larval dispersal in the “downstream” direction and 75%, 111%, and 220% of larval dispersal in the “upstream” direction (similar results obtained based on mean dispersal values). We conclude that more attention should be given to benthic movements in estimating connectivity and stock structure in American lobster.
47
Leis, Jeffrey M., Richard F. Piola, Amanda C. Hay, Colin Wen, and Kun-Ping Kan. "Ontogeny of behaviour relevant to dispersal and connectivity in the larvae of two non-reef demersal, tropical fish species." Marine and Freshwater Research 60, no. 3 (2009): 211. http://dx.doi.org/10.1071/mf08186.
Full textAbstract:
In demersal marine fishes, the dispersal of larvae determines the geographical scale of population connectivity, and larval behaviour may influence dispersal. Yet, little is known of the ontogeny of behaviours that can influence dispersal. The present study examined the development of these behaviours in pelagic larvae of tropical marine fishes (4–21 mm) that occupy non-reef habitats as adults: Eleutheronema tetradactylum (Polynemidae) and Leiognathus equulus (Leiognathidae). In the laboratory, critical speed (Ucrit) increased from 3 to 34 cm s–1 at 1.3–1.7 cm s–1 per mm of size, with the fastest larvae up to 50% faster. In situ speed increased from 4 to 25 cm s–1 at 0.7–2.2 cm s–1 per mm, and was 10–14 body length s–1 (60–90% of Ucrit). Endurance increased from 0 to >40 km at 2.4–4.7 km per mm. In the sea, orientation precision did not change ontogenetically, both species tended to swim in loops, and neither significant overall directionality nor ontogenetic change in orientation was present. Larval orientation of these non-reef species was less precise than that of reef fishes. The two species differed in depth distribution, and one ascended ontogenetically. These behaviours can potentially influence dispersal outcomes over the full size range of these larvae.
48
Lechner, Aaron, Hubert Keckeis, Elisabeth Schludermann, et al. "Shoreline configurations affect dispersal patterns of fish larvae in a large river." ICES Journal of Marine Science 71, no. 4 (2013): 930–42. http://dx.doi.org/10.1093/icesjms/fst139.
Full textAbstract:
Abstract The dispersal patterns of marked larvae of the nase carp (Chondrostoma nasus L.) were observed alongside dissimilar shoreline configurations in the main channel of the free-flowing Austrian Danube and compared with those of floating particles to investigate the mode of dispersal (active–passive). Individuals of different larval stages and floats at similar densities were released at an artificial rip-rap with groynes and a rehabilitated gravel bar. In both habitats, marked individuals were recaptured during the sampling period of 4 d after release. Relevant shoreline attributes for larval dispersal, such as the accessibility of nursery habitats, connectivity between adjacent habitats, and retention potential, were more pronounced at the gravel bar than at the rip-rap. At the gravel bar, larvae moved upstream and downstream within the connected bankside nurseries and displayed longer residence times. Larvae settled in groyne fields along the rip-rap as well; however, longitudinal dispersal was disrupted by groynes, forcing larvae to enter the main channel. Rather than settling in subsequent groyne fields, we assume that these larvae are displaced downstream and potentially lost from the local population.
49
Cruz, Raúl, Carlos A. Borda, João V. M. Santana, et al. "Life cycle and connectivity of the spiny lobster, Panulirus spp.: case studies from Brazil and the Wider Caribbean (Decapoda, Achelata)." Crustaceana 94, no. 5 (2021): 603–45. http://dx.doi.org/10.1163/15685403-bja10116.
Full textAbstract:
Abstract In this study, we look at recent developments in our understanding of the life cycle of the red spiny lobster Panulirus argus (Latreille, 1804) and examine the evidence for connectivity between geographical regions, especially the north-northeast Brazilian continental shelf and the Wider Caribbean. The study also covers aspects of reproduction, phyllosoma density, large-scale oceanic circulation, self-recruitment, settlement patterns, ecological behaviour, and the impact of the Amazon and Orinoco river discharge on recruitment. Our findings support the hypothesis that lobster larvae are transported by ocean currents and free eddies from Brazil to the Caribbean via the Lesser Antilles, outlining a south-to-north connectivity. In addition, we look into the probable existence of hybrids between sympatric lobster species, as evidenced by differences in colour patterns and morphology.
50
Hinrichsen, Hans-Harald, Christoph Petereit, Anders Nissling, Isa Wallin, Didzis Ustups, and Ann-Britt Florin. "Survival and dispersal variability of pelagic eggs and yolk-sac larvae of central and eastern baltic flounder (Platichthys flesus): application of biophysical models." ICES Journal of Marine Science 74, no. 1 (2016): 41–55. http://dx.doi.org/10.1093/icesjms/fsw163.
Full textAbstract:
A hydrodynamic model coupled with a Lagrangian particle tracking technique was utilized to simulate spatially and temporally resolved long-term environmentally related (i) size of habitat suitable for reproduction, (ii) egg/yolk-sac larval survival, (iii) separation of causes of mortality, and (iv) connectivity between spawning areas of Baltic flounder with pelagic eggs. Information on reproduction habitat requirements and mortality sources were obtained from field or laboratory studies. In our modelling study we only quantified physical processes generating heterogeneity in spatial distribution of eggs and yolk-sac larvae, as e.g. predation is not accounted for. The spatial extent of eggs and larvae represented as modelled particles is primarily determined by oxygen and salinity conditions. The reproduction habitat most suitable was determined for the Gdansk Deep, followed by the Bornholm Basin. Relatively low habitat suitability was obtained for the Arkona Basin and the Gotland Basin. The model runs also showed yolk-sac larval survival to be to a large extent affected by sedimentation. Eggs initially released in the Arkona Basin and Bornholm Basin are strongly affected by sedimentation compared with those released in the Gdansk Deep and Gotland Basin. Highest relative survival of eggs occurred in the Gdansk Deep and in the Bornholm Basin. Relatively low survival rates in the Gotland Basin were attributable to oxygen-dependent mortality. Oxygen content had almost no impact on survival in the Arkona Basin. For all spawning areas mortality caused by lethally low temperatures was only evident after severe winters. Buoyancy of eggs and yolk-sac larvae in relation to topographic features appear as a barrier for the transport of eggs and yolk-sac larvae and potentially limits the connectivity of early life stages between the different spawning areas.