970 resultados para conservation management


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Executive Summary: Baseline characterization of resources is an essential part of marine protected area (MPA) management and is critical to inform adaptive management. Gray’s Reef National Marine Sanctuary (GRNMS) currently lacks adequate characterization of several key resources as identified in the 2006 Final Management Plan. The objectives of this characterization were to fulfill this need by characterizing the bottom fish, benthic features, marine debris, and the relationships among them for the different bottom types within the sanctuary: ledges, sparse live bottom, rippled sand, and flat sand. Particular attention was given to characterizing the different ledge types, their fish communities, and the marine debris associated with them given the importance of this bottom type to the sanctuary. The characterization has been divided into four sections. Section 1 provides a brief overview of the project, its relevance to sanctuary needs, methods of site selection, and general field procedures. Section 2 provides the survey methods, results, discussion, and recommendations for monitoring specific to the benthic characterization. Section 3 describes the characterization of marine debris. Section 4 is specific to the characterization of bottom fish. Field surveys were conducted during August 2004, May 2005, and August 2005. A total of 179 surveys were completed over ledge bottom (n=92), sparse live bottom (n=51), flat sand (n=20), and rippled sand (n=16). There were three components to each field survey: fish counting, benthic assessment, and quantification of marine debris. All components occurred within a 25 x 4 m belt transect. Two divers performed the transect at each survey site. One diver was responsible for identification of fish species, size, and abundance using a visual survey. The second diver was responsible for characterization of benthic features using five randomly placed 1 m2 quadrats, measuring ledge height and other benthic structures, and quantifying marine debris within the entire transect. GRNMS is composed of four main bottom types: flat sand, rippled sand, sparsely colonized live bottom, and densely colonized live bottom (ledges). Independent evaluation of the thematic accuracy of the GRNMS benthic map produced by Kendall et al. (2005) revealed high overall accuracy (93%). Most discrepancies between map and diver classification occurred during August 2004 and likely can be attributed to several factors, including actual map or diver errors, and changes in the bottom type due to physical forces. The four bottom types have distinct physical and biological characteristics. Flat and rippled sand bottom types were composed primarily of sand substrate and secondarily shell rubble. Flat sand and rippled sand bottom types were characterized by low percent cover (0-2%) of benthic organisms at all sites. Although the sand bottom types were largely devoid of epifauna, numerous burrows indicate the presence of infaunal organisms. Sparse live bottom and ledges were colonized by macroalgae and numerous invertebrates, including coral, gorgonians, sponges, and “other” benthic species (such as tunicates, anemones, and bryozoans). Ledges and sparse live bottom were similar in terms of diversity (H’) given the level of classification used here. However, percent cover of benthic species, with the exception of gorgonians, was significantly greater on ledge than on sparse live bottom. Percent biotic cover at sparse live bottom ranged from 0.7-26.3%, but was greater than 10% at only 7 out of 51 sites. Colonization on sparse live bottom is likely inhibited by shifting sands, as most sites were covered in a layer of sediment up to several centimeters thick. On ledge bottom type, percent cover ranged from 0.42-100%, with the highest percent cover at ledges in the central and south-central region of GRNMS. Biotic cover on ledges is influenced by local ledge characteristics. Cluster analysis of ledge dimensions (total height, undercut height, undercut width) resulted in three main categories of ledges, which were classified as short, medium, and tall. Median total percent cover was 97.6%, 75.1%, and 17.7% on tall, medium, and short ledges, respectively. Total percent cover and cover of macroalgae, sponges, and other organisms was significantly lower on short ledges compared to medium and tall ledges, but did not vary significantly between medium and tall ledges. Like sparse live bottom, short ledges may be susceptible to burial by sand, however the results indicate that ledge height may only be important to a certain threshold. There are likely other factors not considered here that also influence spatial distribution and community structure (e.g., small scale complexity, ocean currents, differential settlement patterns, and biological interactions). GRNMS is a popular site for recreational fishing and boating, and there has been increased concern about the accumulation of debris in the sanctuary and potential effects on sanctuary resources. Understanding the types, abundance, and distribution of debris is essential to improving debris removal and education efforts. Approximately two-thirds of all observed debris items found during the field surveys were fishing gear, and about half of the fishing related debris was monofilament fishing line. Other fishing related debris included leaders and spear gun parts, and non-gear debris included cans, bottles, and rope. The spatial distribution of debris was concentrated in the center of the sanctuary and was most frequently associated with ledges rather than at other bottom types. Several factors may contribute to this observation. Ledges are often targeted by fishermen due to the association of recreationally important fish species with this bottom type. In addition, ledges are structurally complex and are often densely colonized by biota, providing numerous places for debris to become stuck or entangled. Analysis of observed boat locations indicated that higher boat activity, which is an indication of fishing, occurs in the center of the sanctuary. On ledges, the presence and abundance of debris was significantly related to observed boat density and physiographic features including ledge height, ledge area, and percent cover. While it is likely that most fishing related debris originates from boats inside the sanctuary, preliminary investigation of ocean current data indicate that currents may influence the distribution and local retention of more mobile items. Fish communities at GRNMS are closely linked to benthic habitats. A list of species encountered, probability of occurrence, abundance, and biomass by habitat is provided. Species richness, diversity, composition, abundance, and biomass of fish all showed striking differences depending on bottom type with ledges showing the highest values of nearly all metrics. Species membership was distinctly separated by bottom type as well, although very short, sparsely colonized ledges often had a similar community composition to that of sparse live bottom. Analysis of fish communities at ledges alone indicated that species richness and total abundance of fish were positively related to total percent cover of sessile invertebrates and ledge height. Either ledge attribute was sufficient to result in high abundance or species richness of fish. Fish diversity (H`) was negatively correlated with undercut height due to schools of fish species that utilize ledge undercuts such as Pareques species. Concurrent analysis of ledge types and fish communities indicated that there are five distinct combinations of ledge type and species assemblage. These include, 1) short ledges with little or no undercut that lacked many of the undercut associated species except Urophycis earlii ; 2) tall, heavily colonized, deeply undercut ledges typically with Archosargus probatocephalus, Mycteroperca sp., and Pareques sp.; 3) tall, heavily colonized but less undercut with high occurrence of Lagodon rhomboides and Balistes capriscus; 4) short, heavily colonized ledges typically with Centropristis ocyurus, Halichoeres caudalis, and Stenotomus sp.; and 5) tall, heavily colonized, less undercut typically with Archosargus probatocephalus, Caranx crysos and Seriola sp.. Higher levels of boating activity and presumably fishing pressure did not appear to influence species composition or abundance at the community level although individual species appeared affected. These results indicate that merely knowing the basic characteristics of a ledge such as total height, undercut width, and percent cover of sessile invertebrates would allow good prediction of not only species richness and abundance of fish but also which particular fish species assemblages are likely to occur there. Comparisons with prior studies indicate some major changes in the fish community at GRNMS over the last two decades although the causes of the changes are unknown. Species of interest to recreational fishermen including Centropristis striata, Mycteroperca microlepis, and Mycteroperca phenax were examined in relation to bottom features, areas of assumed high versus low fishing pressure, and spatial dispersion. Both Mycteroperca species were found more frequently when undercut height of ledges was taller. They often were found together in small mixed species groups at ledges in the north central and southwest central regions of the sanctuary. Both had lower mode size and proportion of fish above the fishery size limit in heavily fished areas of the sanctuary (i.e. high boat density) despite the presence of better habitat in that region. Black sea bass, C. striata, occurred at 98% of the ledges surveyed and appeared to be evenly distributed throughout the sanctuary. Abundance was best explained by a positive relationship with percent cover of sessile biota but was also negatively related to presence of either Mycteroperca species. This may be due to predation by the Mycteroperca species or avoidance of sites where they are present by C. striata. Suggestions for monitoring bottom features, marine debris, and bottom fish at GRNMS are provided at the end of each chapter. The present assessment has established quantitative baseline characteristics of many of the key resources and use issues at GRNMS. The methods can be used as a model for future assessments to track the trajectory of GRNMS resources. Belt transects are ideally suited to providing efficient and quantitative assessment of bottom features, debris, and fish at GRNMS. The limited visibility, sensitivity of sessile biota, and linear nature of ledge habitats greatly diminish the utility of other sampling techniques. Ledges should receive the bulk of future characterization effort due to their importance to the sanctuary and high variability in physical structure, benthic composition, and fish assemblages. (PDF contains 107 pages.)

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The 17th Annual Sea Turtle Symposium was held at the Delta Orlando Resort in Orlando, Florida U.S.A. from March 4-8, 1997. The symposium was hosted by Florida Atlantic University, Mote Marine Laboratory, University of Central Florida, University of Florida, Florida Atlantic University and the Comité Nacional para la Conservación y Protección de las Totugas Marinas. The 17th was the largest symposium to date. A total of 720 participants registered, including sea turtle biologists, students, regulatory personnel, managers, and volunteers representing 38 countries. In addition to the United States, participants represented Australia, Austria, the Bahamas, Bonaire, Bermuda, Brazil, Canada, Colombia, Costa Rica, Croatia, Cuba, Cyprus, Dominican Republic, Ecuador, England, Guatemala, Greece, Honduras, India, Italy, Japan, Madagascar, Malaysia, Mexico, The Netherlands, Nicaragua, Peru, Philippines, Republic of Seychelles, Scotland, Spain, Sri Lanka, Switzerland, Taiwan, Turkey, Uruguay, and Venezuela. In addition to the 79 oral, 2 video, and 120 poster presentations, 3 workshops were offered: Selina Heppell (Duke University Marine Laboratory) provided “Population Modeling,” Mike Walsh and Sam Dover (Sea World-Orlando) conducted “Marine Turtle Veterinary Medicine” and “Conservation on Nesting Beaches” was offered by Blair Witherington and David Arnold (Florida Department of Environmental Protection). On the first evening, P.C.H. Pritchard delivered a thoughtful retrospect on Archie Carr that showed many sides of a complex man who studied and wrote about sea turtles. It was a presentation that none of us will forget. The members considered a number of resolutions at the Thursday business meeting and passed six. Five of these resolutions are presented in the Commentaries and Reviews section of Chelonian Conservation and Biology 2(3):442-444 (1997). The symposium was fortunate to have many fine presentations competing for the Archie Carr Best Student Presentations awards. The best oral presentation award went to Amanda Southwood (University of British Columbia) for “Heart rates and dive behavior of the leatherback sea turtle during the internesting interval.” The two runners-up were Richard Reina (Australian National University) for “Regulation of salt gland activity in Chelonia mydas” and Singo Minamikawa (Kyoto University) for “The influence that artificial specific gravity change gives to diving behavior of loggerhead turtles”. The winner of this year’s best poster competition was Mark Roberts (University of South Florida) for his poster entitled “Global population structure of green sea Turtles (Chelonia mydas) using microsatellite analysis of male mediated gene flow.” The two runners-up were Larisa Avens (University of North Carolina-Chapel Hill) for “Equilibrium responses to rotational displacements by hatchling sea turtles: maintaining a migratory heading in a turbulent ocean” and Annette Broderick (University of Glasgow) for “Female size, not length, is a correlate of reproductive output.” The symposium was very fortunate to receive a matching monetary and subscription gift from Anders J. G. Rhodin of the Chelonian Research Foundation. These enabled us to more adequately reward the fine work of students. The winners of the best paper and best poster awards received $400 plus a subscription to Chelonian Conservation and Biology. Each runner up received $100. The symposium owes a great debt to countless volunteers who helped make the meeting a success. Those volunteers include: Jamie Serino, Alan Bolton, and Karen Bjorndal, along with the UF students provided audio visual help, John Keinath chaired the student awards committee, Mike Salmon chaired the Program Commiteee, Sheryan Epperly and Joanne Braun compiled the Proceedings, Edwin Drane served as treasurer and provided much logistical help, Jane Provancha coordinated volunteers, Thelma Richardson conducted registration, Vicki Wiese coordinated food and beverage services, Jamie Serino and Erik Marin coordinated entertainment, Kenneth Dodd oversaw student travel awards, Traci Guynup, Tina Brown, Jerris Foote, Dan Hamilton, Richie Moretti, and Vicki Wiese served on the time and place committee, Blair Witherington created the trivia quiz, Tom McFarland donated the symposium logo, Deborah Crouse chaired the resolutions committee, Pamela Plotkin chaired the nominations committee, Sally Krebs, Susan Schenk, and Larry Wood conducted the silent auction, and Beverly and Tom McFarland coordinated all 26 vendors. Many individuals from outside the United States were able to attend the 17th Annual Sea Turtle Symposium thanks to the tireless work of Karen Eckert, Marydele Donnelly, and Jack Frazier in soliciting travel assistance for a number of international participants. We are indebted to those donating money to the internationals’ housing fund (Flo Vetter Memorial Fund, Marinelife Center of Juno Beach, Roger Mellgren, and Jane Provancha). We raise much of our money for international travel from the auction; thanks go to auctioneer Bob Shoop, who kept our auction fastpaced and entertaining, and made sure the bidding was high. The Annual Sea Turtle Symposium is unequaled in its emphasis on international participation. Through international participation we all learn a great deal more about the biology of sea turtles and the conservation issues that sea turtles face in distant waters. Additionally, those attending the symposium come away with a tremendous wealth of knowledge, professional contacts, and new friendships. The Annual Sea Turtle Symposium is a meeting in which pretenses are dropped, good science is presented, and friendly, open communication is the rule. The camaraderie that typifies these meetings ultimately translates into understanding and cooperation. These aspects, combined, have gone and will go a long way toward helping to protect marine turtles and toward aiding their recovery on a global scale. (PDF contains 342 pages)

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Executive Summary: Observations show that warming of the climate is unequivocal. The global warming observed over the past 50 years is due primarily to human-induced emissions of heat-trapping gases. These emissions come mainly from the burning of fossil fuels (coal, oil, and gas), with important contributions from the clearing of forests, agricultural practices, and other activities. Warming over this century is projected to be considerably greater than over the last century. The global average temperature since 1900 has risen by about 1.5ºF. By 2100, it is projected to rise another 2 to 11.5ºF. The U.S. average temperature has risen by a comparable amount and is very likely to rise more than the global average over this century, with some variation from place to place. Several factors will determine future temperature increases. Increases at the lower end of this range are more likely if global heat-trapping gas emissions are cut substantially. If emissions continue to rise at or near current rates, temperature increases are more likely to be near the upper end of the range. Volcanic eruptions or other natural variations could temporarily counteract some of the human-induced warming, slowing the rise in global temperature, but these effects would only last a few years. Reducing emissions of carbon dioxide would lessen warming over this century and beyond. Sizable early cuts in emissions would significantly reduce the pace and the overall amount of climate change. Earlier cuts in emissions would have a greater effect in reducing climate change than comparable reductions made later. In addition, reducing emissions of some shorter-lived heat-trapping gases, such as methane, and some types of particles, such as soot, would begin to reduce warming within weeks to decades. Climate-related changes have already been observed globally and in the United States. These include increases in air and water temperatures, reduced frost days, increased frequency and intensity of heavy downpours, a rise in sea level, and reduced snow cover, glaciers, permafrost, and sea ice. A longer ice-free period on lakes and rivers, lengthening of the growing season, and increased water vapor in the atmosphere have also been observed. Over the past 30 years, temperatures have risen faster in winter than in any other season, with average winter temperatures in the Midwest and northern Great Plains increasing more than 7ºF. Some of the changes have been faster than previous assessments had suggested. These climate-related changes are expected to continue while new ones develop. Likely future changes for the United States and surrounding coastal waters include more intense hurricanes with related increases in wind, rain, and storm surges (but not necessarily an increase in the number of these storms that make landfall), as well as drier conditions in the Southwest and Caribbean. These changes will affect human health, water supply, agriculture, coastal areas, and many other aspects of society and the natural environment. This report synthesizes information from a wide variety of scientific assessments (see page 7) and recently published research to summarize what is known about the observed and projected consequences of climate change on the United States. It combines analysis of impacts on various sectors such as energy, water, and transportation at the national level with an assessment of key impacts on specific regions of the United States. For example, sea-level rise will increase risks of erosion, storm surge damage, and flooding for coastal communities, especially in the Southeast and parts of Alaska. Reduced snowpack and earlier snow melt will alter the timing and amount of water supplies, posing significant challenges for water resource management in the West. (PDF contains 196 pages)

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This report documents abundance and cover for selected elements of the benthic coral reef assemblage at the site of the 1984 grounding of the M/V Wellwood on Molasses Reef, Florida Keys. The purpose of the effort was to establish a pre-construction baseline before the installation of reef modules at the site. The installation process is intended to stabilize fractured substrates that were recently exposed by storm impacts, and to provide three-dimensional relief in order to enhance reef community recovery. It is hoped that the restoration effort will result in a biological assemblage with the character of the transition community that would exist there had the incident not occurred. To date, the assemblage has developed the character of a comparatively featureless hard ground similar in composition to hard ground areas and transition zones surrounding the grounding site. These data will allow scientists and resource managers to better track the trajectory of recovery following the installation of modules. Direct counts of scleractinian and gorgonian corals, hydrocorals of the genus Millepora, and zoanthids of the genus Palythoa were made in three areas within and around the grounding site. The site is poorly developed with respect to scleractinian colony size and cover compared to surrounding areas. Key scleractinian species necessary for the development of topographic relief in the area denuded by the grounding are not well represented in the current community. Though gorgonian cover and richness is similar in all study areas, gorgonian community recovery in the damaged area is not complete. Unlike surrounding areas, one species, Pseudopterogorgia americana, accounts for over half of all corals at the grounding site, over 80% of all gorgonians, and nearly all the coral cover. Based on these findings and other observations made in the 18 years since the grounding, recommendations are made that should be considered in the course of human intervention targeted at stabilizing and enhancing the site. (PDF contains 24 pages.)

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In Central California, and elsewhere around the world, a great deal of discussion is occurring about the use of marine protected areas (MPAs) as a tool to help manage marine resources. This discussion is taking place because there is growing evidence that humans have depleted marine resources in many parts of the world, often despite strong regulatory efforts. Moreover, there is also mounting evidence that the degradation of marine resources began long ago, and we do not fully realize how much humans have altered “natural” environments. This uncertainty has led people to discuss the use of MPAs as a precautionary tool to prevent depletion or extinction of marine resources, and as a means of redressing past damages. The discussion about the use of marine reserves is increasing in intensity in California because several resource management agencies are considering reserves as they create or revise management plans. Often, the discussions surrounding this important public policy debate lead to questions about the biological or ecological value of existing marine protected areas. More than 100 MPAs exist along the coast of California. Many of these were established arbitrarily and lack specific purposes. Some California marine protected areas also have co-occurring or overlapping boundaries, have conflicting designations for use, and have conflicting rules and regulations. Because few of the existing marine protected areas have clearly articulated goals or objectives, however, it is difficult or impossible to evaluate their ecological effectiveness. (PDF contains 18 pages.)

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The Olympic Coast National Marine Sanctuary (OCNMS or Sanctuary) planned and organized the 1998 Research Workshop as part of its mission to protect and improve understanding of its marine resources through research and education programs. The Sanctuary is also mandated to coordinate and facilitate information exchanges and sponsors periodic research workshops to that end. The goals of the 1998 Research Workshop were as follows: A. Highlight and prioritize research needs for the Sanctuary relative to the development of a framework for a five-year research plan; B. Build on results from the Olympic Coast Marine Research Workshop of 1996; C. Present recent/ongoing research; D. Share multi-disciplinary information; E. Select priority sites for multi-disciplinary studies; and F. Promote student participation and research. (PDF contains 93 pages.)

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Coastal ecosystems and the services they provide are adversely affected by a wide variety of human activities. In particular, seagrass meadows are negatively affected by impacts accruing from the billion or more people who live within 50 km of them. Seagrass meadows provide important ecosystem services, including an estimated $1.9 trillion per year in the form of nutrient cycling; an order of magnitude enhancement of coral reef fish productivity; a habitat for thousands of fish, bird, and invertebrate species; and a major food source for endangered dugong, manatee, and green turtle. Although individual impacts from coastal development, degraded water quality, and climate change have been documented, there has been no quantitative global assessment of seagrass loss until now. Our comprehensive global assessment of 215 studies found that seagrasses have been disappearing at a rate of 110 square kilometers per year since 1980 and that 29% of the known areal extent has disappeared since seagrass areas were initially recorded in 1879. Furthermore, rates of decline have accelerated from a median of 0.9% per year before 1940 to 7% per year since 1990. Seagrass loss rates are comparable to those reported for mangroves, coral reefs, and tropical rainforests and place seagrass meadows among the most threatened ecosystems on earth.

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In 1992 and 1993, researchers from the National Marine Mammal Laboratory initiated photo-identification studies on Alaskan killer whales, Orcinus orca. Waters from Kodiak Island west to the central and eastern Aleutian Islands and southeastern Bering Sea were surveyed. A total of 289 individual whales were identified. A photographic record of the whales encountered during these surveys is presented. When photographs of the 289 individual whales were compared among various regions in Alaska (Prince William Sound and Southeast Alaska) and areas outside Alaska (British Columbia, Washington, and California), 11 matches were found. The count is conservative because the 1992 and 1993 surveys were limited in geographical range, restricted to summer periods, and whales may have been missed along the survey trackline. Future research incorporating both photoidentification studies and line transect surveys will provide reliable abundance estimates of Alaskan killer whales. (PDF file contains 58 pages.)

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Current information is reviewed that provides clues to the intraspecific structure of dolphin species incidently killed in the yellowfin tuna purse-seine fishery of the eastern tropical Pacific (ETP). Current law requires that management efforts are focused on the intraspecific level, attempting to preserve local and presumably locally adapted populations. Four species are reviewed: pantropical spotted, Stenella attenuata; spinner, S. longirostTis; striped, S. coeruleoalba; and common, Delphinus delphis, dolphins. For each species, distributional, demographic, phenotypic, and genotypic data are summarized, and the putative stocks are categorized based on four hierarchal phylogeographic criteria relative to their probability of being evolutionarily significant units. For spotted dolphins, the morphological similarity of animals from the south and the west argues that stock designations (and boundaries) be changed from the current northern offshore and southern offshore to northeastern offshore and a combined western and southern offshore. For the striped dolphin, we find little reason to continue the present division into geographical stocks. For common dolphins, we reiterate an earlier recommendation that the long-beaked form (Baja neritic) and the northern short-beaked form be managed separately; recent morphological and genetic work provides evidence that they are probably separate species. Finally, we note that the stock structure of ETP spinner dolphins is complex, with the whitebelly form exhibiting characteristics of a hybrid swarm between the eastern and pantropical subspecies. There is little morphological basis at present for division of the whitebelly spinner dolphin into northern and southern stocks. However, we recommend continued separate management of the pooled whitebelly forms, despite their hybrid/intergrade status. Steps should be taken to ensure that management practices do not reduce the abundance of eastern relative to whitebelly spinner dolphins. To do so may lead to increased invasion of the eastern's stock range and possible replacement of the eastern spinner dolphin genome.(PDF file contains 24 pages.)

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Eight hundred sixty-five records of Kemp's ridley sea turtles (Lepidochelys kempi) reported from Texas between the late 1940's to April 1990 were compiled from six data bases and the literature, then plotted on a series of Texas maps. Four categories of Kemp's ridleys are identified throughout the atlas: head-started (turtles that are raised in captivity their first year of life), wild, historical (pre-1980), and nesters. Geographic, seasonal, and size distributions of the turtle categories are plotted by regions. Most Kemp's ridleys were reported from the northeast and central Texas coast. They were reported from both inshore (landward of barrier islands) and offshore (seaward of barrier islands). Scattered nestings occurred in the central to southern regions. Kemp's ridleys were found more often during the spring and summer. A total of 546 turtle records contained measurements; most were 20-59.9 cm curved carapace length and considered sub-adults. Comparison of distributions of head-started and wild Kemp's ridleys suggests head-started Kemp's ridleys inhabit the same areas as wild Kemp's ridleys. (PDF file contains 56 pages.)

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Over a decade ago, in August 1977, the First Marine Mammal Stranding Workshop was convened in Athens, Georgia. That workshop, organized by j.R. Geraci and D.J. St. Aubin, not only considered biology and pathology of stranded marine mammals, but it also served as a springboard for the formation of regional marine mammal stranding networks in the United States. The ramifications have been extremely important to the field of marine mammalogy since, for some species, examination or rehabilitation of stranded specimens serves as virtually the only source of information on distribution, anatomy, physiology, reproduction, and pathology. The First Marine Mammal Stranding Workshop led to increased awareness of the marine mammals themselves, as well as the logistic and legal factors associated with effective handling of the animals. A number of individuals indicated that they felt that a Second Marine Mammal Stranding Workshop held prior to the Seventh Biennial Conference on the Biology of Marine Mammals (Miami, Florida; December 1987) would be both timely and productive. Accordingly, we organized the workshop and scheduled it to occur on 3-5 December. Our goals for the workshop were several, including 1) providing descriptions of some research, especially new techniques, regarding stranded marine mammals; 2) providing a forum where scientists could interact and possibly initiate cooperative research activities; 3) presenting information regarding procedures used effectively to handle stranded animals; 4) assessing ways to standardize data and specimen collection, archiving, and retrieval; and 5) providing a forum for assessing accomplishments and status of regional stranding networks to date, as well as for making recommendations regarding future activities of the networks. Nearly 100 individuals representing Federal and State governments, academic institutions, the oceanarium industry, consulting groups, conservation organizations, and the private sector attended the workshop (see Workshop Participants, this volume). (PDF file contains 166 pages.)

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Each year, more than 500 motorized vessel groundings cause widespread damage to seagrasses in Florida Keys National Marine Sanctuary (FKNMS). Under Section 312 of the National Marine Sanctuaries Act (NMSA), any party responsible for the loss, injury, or destruction of any Sanctuary resource, including seagrass, is liable to the United States for response costs and resulting damages. As part of the damage assessment process, a cellular automata model is utilized to forecast seagrass recovery rates. Field validation of these forecasts was accomplished by comparing model-predicted percent recovery to that which was observed to be occurring naturally for 30 documented vessel grounding sites. Model recovery forecasts for both Thalassia testudinum and Syringodium filiforme exceeded natural recovery estimates for 93.1% and 89.5% of the sites, respectively. For Halodule wrightii, the number of over- and under-predictions by the model was similar. However, where under-estimation occurred, it was often severe, reflecting the well-known extraordinary growth potential of this opportunistic species. These preliminary findings indicate that the recovery model is consistently generous to Responsible Parties in that the model forecasts a much faster recovery than was observed to occur naturally, particularly for T. testudinum, the dominant seagrass species in the region and the species most often affected. Environmental setting (i.e., location, wave exposure) influences local seagrass landscape pattern and may also play a role in the recovery dynamics for a particular injury site. An examination of the relationship between selected environmental factors and injury recovery dynamics is currently underway. (PDF file contains 20 pages.)

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Biología pesquera de agua dulce.Curso 1990. Ictiología Continental Argentina. Curso de posgrado 2000. Ictiología Continental Argentina. Curso de posgrado 2002. pdf contains 147 pages.

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In accordance with the recommendations of the Committee on Fisheries (COFI), FAO prepared the first draft of the technical guidelines in relation to Fishing Operations, which were submitted to the Technical Consultation on the Code of Conduct for Responsible Fishing, Rome, 26 September to 5 October 1994. The draft was prepared taking into account the Declaration of Cancún, Agenda 21 of United Nations Conference on Environment and Development (UNCED) and the Report of the Expert Consultation on Responsible Fishing Operations, Sidney, British Colombia, Canada, 6 -11 June 1994. Thereafter, the draft was revised taking into account, the negotiations at the UN Conference on Straddling Fish Stocks and Highly Migratory Fish Stocks, the elaboration of the Code as well as developments at the International Maritime Organization (IMO) with regard to the Protocol to the Torremolinos International Convention on Fishing Vessel Safety and the new International Convention on Training, Certification and Watchkeeping for Fishing Vessel Personnel, 1995. Technical Guidelines are given in support of the implementation of the Code in relation to fishing operations. These are addressed to States, international organizations, fisheries management bodies, owners, managers and charterers of fishing vessels as well as fishers and their organizations. Guidance is also given with respect to the general public. (PDF contains 93 pages)

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The present fishing effort regulation for bottom trawls in the North Sea (EU 40/2008) reduces the fishing effort with larger co-dend mesh sizes (> 100 mm mesh opening) to 86 fishing days per year. The aim of this technical measure is the protection of the weak cod stock usually harvested with this mesh opening. By combining the results of our selectivity investigations on plaice during a commercial fishing trip and the samples taken within the frame of the EU data collection regulation (DCR) we could draw conclusions on commercial and non-commercial fish species. When using codend meshes with larger mesh opening the discard was reduced remarkably. In the reference codend with 80 mm mesh opening the undersized bycatch was 47 % of the total catch of plaice, in the experimental codends with 120 mm mesh opening it was only 7 % and with 130 mm mesh opening just 3 %. On the other hand however, the applied mesh openings in the experimental codends let escape marketable plaice to some extent. The loss of catch was assessed on the basis of fish numbers per length class using a length-weight conversion rate from the DCR. The loss by weight of marketable fish with 120 mm codend mesh opening was 18 %, and 28 % with 130 mm codend mesh opening. To assure the protection of young round and flatfish with one general mesh size, a new regulation should prescribe a minimum mesh opening of 120 mm, accompanied by an expansion of the fishing effort.