Download or read book Identifying Suitable Habitat for Three Highly Migratory Sharks Great Hammerhead Tiger and Bull and Assessing Their Spatial Vulnerability to Commercial Longline Fishing in the Southwest Atlantic Ocean and Gulf of Mexico written by Hannah Calich and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Aquatic highly migratory species (HMS) are economically and ecologically important, however, their highly migratory nature makes them difficult to study and thus there are knowledge gaps relating to their movement and habitat use patterns. Highly migratory sharks are likely to interact with commercial longline fishing gear and be caught as target or bycatch, which can threaten their populations. Understanding the environmental factors that influence and drive the movements of highly migratory sharks may help researchers better predict their presence and subsequently identify areas where they are vulnerability to fisheries. Here I evaluated the overlap between habitat suitability and gear restricted zones for three co-occurring apex predatory sharks in the Southwest Atlantic Ocean and Gulf of Mexico (great hammerhead Sphyrna mokarran, tiger Galeocerdo cuvier, and bull sharks Carcharhinus leucas) to identify areas in this region where these species are vulnerable to and protected from commercial longline fishing. This research was accomplished in three integrated steps. First, I reviewed and summarized what is known about the environmental drivers of great hammerhead, tiger, and bull shark habitat use and movement patterns. Second, I used the results of this review to parameterize and subsequently generate habitat suitability models for these three species. Third, I used these models to spatially compare where each species' highly suitable habitat overlaps with longline gear restricted areas within the Southwest Atlantic Ocean and Gulf of Mexico, to identify regions where these species were both vulnerable to and protected from longline fishing gear. The results of this thesis have implications to the management of these species as well as for the conservation of other highly migratory aquatic species.
Download or read book Quantifying Habitat Protection and Preference for Shark Species in South Florida and The Bahamas Using Satellite Telemetry written by Fiona Graham and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine protected areas (MPAs) are effective at employing ecosystem-based management as a conservation tool, however these networks of protected zones must be carefully chosen. Therefore, strategic area placement and size is crucial for the best conservation outcome. While the benefits of implementing clear protected zones are obvious for species that live sedentary lifestyles, the proportion of habitat protection that they offer to wide-ranging species is less clear. Here, we analyze satellite telemetry data in order to determine key habitat areas for three wide-ranging shark species in both the south Florida and Bahamas regions, and then quantify the level of potential habitat protection that is offered to these species by both management zones within Florida and The Bahamas EEZ. We further assess their movements and habitat use with regards to habitat preference, specifically water column depth and distance from land. The three species selected for this study are the great hammerhead (Sphyrna mokarran), tiger shark (Galeocerdo cuvier), and bull shark (Carcharhinus leucas). These species were selected primarily because, as a group, they are the apex predators in the region, are representative of the region's marine megafauna, and they rank as a conservation priority. The study area encompasses a number of different MPAs, each differing in qualities such as purpose, management agency, level of protection, and restrictions on human uses. However, for this study we are most concerned with locational boundaries and level of protection offered. More specifically, we primarily look at those areas that restrict fishing, which is a major anthropogenic threat to the study species. To accomplish this analysis, we use ArcGIS, a geographical information systems program, to overlay MPA data in the study region with analysis of satellite telemetry data. Core activity space was determined using kernel density estimates, and the 50% kernel density estimate isolpleth was considered "critical habitat." The proportion of critical habitat that is protected for each target species was then calculated by determining the percent overlap of the critical habitat area with protected areas relevant to each species. To supplement this assessment, we then evaluate habitat preference based on overlap of critical habitat use areas and physical factors, where bathymetry data is overlaid with kernel density estimate isopleths. Mean and max distance from land was also calculated for all interpolated points for each species, and all interpolated points within defined critical habitat boundaries. This analysis allowed us to quantify habitat use with regards to water column depth and distance from shore. Finally, we created separate seasonal kernel density estimates for all species for the wet and dry seasons, in order to evaluate seasonal habitat preference. Results from 26 tagged bull sharks demonstrate that Biscayne and Everglades National Parks are high use areas for these sharks, and that none of their critical habitat is currently within areas that protect the species from fishing pressure, more specifically prohibiting the landing of the species. Analysis of data from 22 tagged great hammerhead sharks illustrates that 17.88% of their critical habitat is currently protected, almost all of which is due to regulations that prohibit the landing of the species within Florida state waters. Finally, 34.74% of tagged tiger shark (n=44) critical habitat is currently protected, due to regulations that prohibit the landing of the species within Florida state waters and regulations prohibiting shark fishing within The Bahamas EEZ. Habitat preference results are consistent with our previous analysis, and show that bull sharks prefer depths of less than 10 meters and are, on average, very close to land. We found that mean distance to shore for all interpolated bull shark points was 6.4 km, and mean distance to shore for all interpolated bull shark points that lie within their defined critical habitat area was 4.3 km. Data from our 44 tagged tiger sharks demonstrated that 78.25% of their critical habitat consists of depths greater than 100 meters and mean distance from land for all points was furthest for this species, at 176.6. Average distance to shore for all points within the tiger shark critical habitat was 71.9. We found that great hammerhead critical habitat was split relatively evenly between each depth range, and their mean distance to shore for all points and for only those points within their critical habitat was 82.8km and 16.6km, respectively. Finally, seasonal kernel density estimates created for the wet and dry seasons showed that habitat use does indeed seem to vary by season. Many wide-ranging marine top predators are experiencing population declines globally (Pauly et al. 1998, Myers & Worm 2003, Hampton et al. 2005, Dulvy et al. 2008). Marine reserves are the first step toward evaluating how effective these MPAs are as conservation tools and understanding how we can work to improve them. The results from this study have valuable implications for marine conservation planning and help to develop an understanding of the current and potential level of protection for the top predator species that play integral roles in south Florida's and The Bahamas' ecosystems.
Download or read book Global Perspectives on the Biology and Life History of the White Shark written by Michael L. Domeier and published by CRC Press. This book was released on 2012-02-03 with total page 571 pages. Available in PDF, EPUB and Kindle. Book excerpt: Inspired by the International White Shark Symposium in 2010, Global Perspectives on the Biology and Life History of the White Shark incorporates the most important contemporary research findings into a single peer-reviewed book. This beautifully illustrated reference represents a historic change in the context of White Shark (Carcharodon carcharias) research. Once considered one of the most poorly understood and difficult sharks to study, this timely book recognizes a new sophisticated focus on the White Shark, raising its status from obscurity to enlightenment. The Global Perspectives on the Biology and Life History of the White Shark celebrates the White Shark as the most studied shark in the sea. Within the chapters one can find new insights into a vast range of topics, such as behavior, physiology, migration patterns, habitat preferences, daily activity patterns, molecular genetics, reproductive biology and new research methods. The book also delves into population monitoring and policy options for managers and researchers.
Download or read book Habitats and Biota of the Gulf of Mexico Before the Deepwater Horizon Oil Spill written by C. Herb Ward and published by Springer. This book was released on 2017-06-26 with total page 948 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is open access under a CC BY-NC 2.5 license. The Gulf of Mexico is an open and dynamic marine ecosystem rich in natural resources but heavily impacted by human activities, including agricultural, industrial, commercial and coastal development. The Gulf of Mexico has been continuously exposed to petroleum hydrocarbons for millions of years from natural oil and gas seeps on the sea floor, and more recently from oil drilling and production activities located in the water near and far from shore. Major accidental oil spills in the Gulf are infrequent; two of the most significant include the Ixtoc I blowout in the Bay of Campeche in 1979 and the Deepwater Horizon Oil Spill in 2010. Unfortunately, baseline assessments of the status of habitats and biota in the Gulf of Mexico before these spills either were not available, or the data had not been systematically compiled in a way that would help scientists assess the potential short-term and long-term effects of such events. This 2-volume series compiles and summarizes thousands of data sets showing the status of habitats and biota in the Gulf of Mexico before the Deepwater Horizon Oil Spill. Volume 2 covers historical data on commercial and recreational fisheries, with an analysis of marketing trends and drivers; ecology, populations and risks to birds, sea turtles and marine mammals in the Gulf; and diseases and mortalities of fish and other animals that inhabit the Gulf of Mexico.
Download or read book Review of Studies of Tuna Food in the Atlantic Ocean written by Alexander Dragovich and published by . This book was released on 1969 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Elasmobranch Husbandry Manual written by Mark F. L. Smith and published by . This book was released on 2004 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Field Identification Guide to the Sharks and Rays of the Red Sea and Gulf of Aden written by Ramón Bonfil and published by Food & Agriculture Org.. This book was released on 2004 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a fully illustrated field guide for the identification of the sharks and rays most relevant to the fisheries of the Red Sea and Gulf of Aden. An extensive literature review and two field surveys in the region were carried out for the preparation of this document. A total of 49 sharks and 45 batoids reliably reported for the region are listed and those common in the fisheries or likely to be found through fisheries operations are fully treated. The guide includes sections on technical terms and measurements for sharks and batoids, and fully illustrated keys to those orders and families that occur in the region. Color plates for a large number of the species are included.
Download or read book The Galapagos Marine Reserve written by Judith Denkinger and published by Springer Science & Business Media. This book was released on 2014-01-24 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on how marine systems respond to natural and anthropogenic perturbations (ENSO, overfishing, pollution, tourism, invasive species, climate-change). Authors explain in their chapters how this information can guide management and conservation actions to help orient and better manage, restore and sustain the ecosystems services and goods that are derived from the ocean, while considering the complex issues that affect the delicate nature of the Islands. This book will contribute to a new understanding of the Galapagos Islands and marine ecosystems.
Download or read book Fishery Management Plan Fisheries Management Plan FMP for Sharks of the Atlantic Ocean written by and published by . This book was released on 1992 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spatial and Behavioral Ecology of the Sand Tiger Shark Carcharias Taurus in the Northwestern Atlantic written by Danielle E. Haulsee and published by . This book was released on 2017 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantifying the biogeography of coastal marine species is difficult and requires innovative study designs. These challenges are the motivation behind this dissertation. The Sand Tiger shark (Carcharias taurus) is an important apex predator in the coastal oceans along the Eastern Coast of the United States. I conducted a study in the Delaware Bay and Mid-Atlantic coastal Ocean, which used historical species location records from acoustic telemetry matched to static and satellite-measured dynamic environmental predictor variables, to create a near-real time predictive species distribution model. Notably we found Sand Tigers were predicted by water temperature, water depth, day length and ocean color absorption in the near-infrared, which likely relates to turbidity in the coastal ocean. In this study I identified the timing and location of migratory corridors used by Sand Tigers, as well as how the timing and location of migration differed between juvenile, mature male and mature female Sand Tigers. ☐ In my second study, I investigated the timing and migration of Sand Tigers along the Delmarva Peninsula on much smaller spatiotemporal scales during their fall migration south, a time during which Sand Tigers are susceptible to anthropogenic threats. For the first time, I used an autonomous underwater vehicle to concurrently detect Sand Tigers carrying acoustic tags, and measure fine scale environmental properties of the sub-surface ocean to determine habitat selectivity. I found that Sand Tigers migrated rapidly and en masse through the coastal ocean off the Delmarva Peninsula and were selecting for waters near-shore, lower in salinity, and higher in color dissolved organic matter. These results support the larger scale patterns in environmental predictors I found in my first study, as well as prove that using autonomous underwater vehicles is an effective method for extending our capabilities of detecting acoustically tagged marine species. ☐ Finally, I developed a novel tagging method that implanted an archival acoustic receiver into the body cavity of Sand Tigers, which were released alive and continued to conduct their annual migration before they were recaptured and the tags were removed. This tagging method allowed me to record associations between Sand Tigers and other acoustically tagged species for one year of the Sand Tigers life. Analysis of that dataset revealed potential fission-fusion behavior, or the change in size and composition of groups, in the Sand Tiger population depending on where the Sand Tigers were along the East Coast, and what they were likely doing during that time (i.e. feeding, searching for mates, migrating, etc.). I observed Sand Tiger aggregations change from mixed groups of male and female juveniles and adults, to groups of only adult males, to solitary phases where Sand Tigers were completely dispersed for weeks at a time. This study is important because it suggests the potential for social behavior in a shark species, but also identifies the possibility of anthropogenic impacts disproportionally impacting one sector of the Sand Tiger population as the composition of their aggregations changes in time and space. This dissertation uses advances in remote sensing and animal tagging methods to provide insights into the species distribution, habitat selection, and the migratory and grouping behavior of a coastal shark species under threat of population decline due to anthropogenic impacts along the East Coast of the United States and provides insights into the ecology and biogeography of this species that will assist managers and researchers in future conservation efforts for this and other imperiled species.
Download or read book Elasmobranchs of the Mediterranean and Black Sea written by Mohamed Nejmeddine Bradai and published by Food & Agriculture Organization of the UN (FAO). This book was released on 2012 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: In many fisheries they are, however, often landed and marketed.
Download or read book Trophic Cascades written by John Terborgh and published by Island Press. This book was released on 2013-06-25 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt: Trophic cascades—the top-down regulation of ecosystems by predators—are an essential aspect of ecosystem function and well-being. Trophic cascades are often drastically disrupted by human interventions—for example, when wolves and cougars are removed, allowing deer and beaver to become destructive—yet have only recently begun to be considered in the development of conservation and management strategies. Trophic Cascades is the first comprehensive presentation of the science on this subject. It brings together some of the world’s leading scientists and researchers to explain the importance of large animals in regulating ecosystems, and to relate that scientific knowledge to practical conservation. Chapters examine trophic cascades across the world’s major biomes, including intertidal habitats, coastal oceans, lakes, nearshore ecosystems, open oceans, tropical forests, boreal and temperate ecosystems, low arctic scrubland, savannas, and islands. Additional chapters consider aboveground/belowground linkages, predation and ecosystem processes, consumer control by megafauna and fire, and alternative states in ecosystems. An introductory chapter offers a concise overview of trophic cascades, while concluding chapters consider theoretical perspectives and comparative issues. Trophic Cascades provides a scientific basis and justification for the idea that large predators and top-down forcing must be considered in conservation strategies, alongside factors such as habitat preservation and invasive species. It is a groundbreaking work for scientists and managers involved with biodiversity conservation and protection.
Download or read book Sharks of the World written by Leonard J. V. Compagno and published by Food & Agriculture Org.. This book was released on 2001 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: An extensively rewritten, revised and updated version of the original FAO Catalogue of Sharks of the World. This volume reviews all 15 families, 25 genera and 57 species of living bullhead, mackerel and carpet sharks, including certain well-established but currently undescribed species, mainly from Australia.
Download or read book The Conservation Status of Australasian Chondrichthyans written by Rachel D. Cavanagh and published by . This book was released on 2003 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sharks of the World written by David A. Ebert and published by Princeton University Press. This book was released on 2021-07-20 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Fully revised and updated"--Back cover.
Download or read book Sharks of the Open Ocean written by Merry D. Camhi and published by John Wiley & Sons. This book was released on 2009-01-21 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: This important and exciting title represents the first authoritative volume focussed on pelagic (open ocean) sharks as a group. Virtually every pelagic shark expert in the world has contributed to this landmark publication which includes the latest data and knowledge on pelagic shark biology, fisheries, management, and conservation. Pelagic sharks face unprecedented levels of exploitation in all the world's oceans through both direct fisheries and by-catch, and effective management for these species is contingent upon solid science and data, which this book brings together for the first time. All those involved in shark biology will need to have a copy of this book.
Download or read book Sharks Rays and Chimaeras written by Sarah L. Fowler and published by IUCN. This book was released on 2005 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:
