871 resultados para Endangered breeds


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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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An early establishment of selective breeding programs on Atlantic salmon has been crucial for the success of developing efficient and sustainable salmon farming in Norway. A national selective breeding program was initiated by AKVAFORSK at the beginning of the 1970s, by collecting fertilized eggs from more than 40 Norwegian river populations. Several private selective breeding programs were also initiated in the 1970s and 1980s. While these private programs were initiated using individual selection (i.e. massselection) to genetically improve growth, the national program was designed to gradually include all economically important traits in the breeding objective (i.e. growth, age at sexual maturation, disease resistance and quality traits) using a combined family and within-family selection strategy. Independent of which selection strategy and program design used, it is important to secure and maintain a broad genetic variation in the breeding populations to maximize selection response. It has been documented that genetically improved salmon from the national selective breeding program grow twice as fast as wild Atlantic salmon and require 25 per cent less feed, while salmon representing the private breeding programs all show an intermediate growth performance. As a result of efficient dissemination of genetically improved Atlantic salmon, the Norwegian salmon farming industry has reduced its feed costs by more than US$ 230 million per year! The national selective breeding program on Atlantic salmon was commercialized into a breeding company (AquaGen) in 1992. Five years later, several private companies and the AKVAFORSK Genetics Center (AFGC) established a second breeding company (SalmoBreed) using breeding candidates from one of the private breeding programs. These two breeding companies have similar products, but different strategies on how to organize the breeding program and to disseminate the genetically improved seed to the Norwegian salmon industry. Greater competition has increased the necessity to document the genetic gain obtained from the different programs and to market the economic benefits of farming the genetically improved breeds. Both breeding companies have organized their dissemination to get a sufficient share of the economic benefits in order to sustain and improve their breeding programs.

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The Cape Canaveral, Florida, marine ecosystem is unique. There are complex current and temperature regimes that form a faunal transition zone between Atlantic tropical and subtropical waters. This zone is rich faunistically and supports large commercial fISheries for fish, scallops, and shrimp. Canaveral is also unique because it has large numbers of sea turtles year-round, this turtle aggregation exhibiting patterned seasonal changes in numbers, size frequency, and sex ratio. Additionally, a significant portion of this turtle aggregation hibernates in the Canaveral ship channel, a phenomenon rare in marine turtle populations. The Cape Canaveral area has the largest year-round concentration of sea turtles in the United States. However, the ship channel is periodically dredged by the U.S. Army Corps of Engineers in order to keep Port Canaveral open to U.S. Navy vessels, and preliminary surveys showed that many sea turtles were incidentally killed during dredging operations. In order for the Corps of Engineers to fulfill its defense dredging responsibilities, and comply with the Endangered Species Act of 1973, an interagency Sea Turtle Task Force was formed to investigate methods of reducing turtle mortalities. This Task Force promptly implemented a sea turtle research plan to determine seasonal abundance, movement patterns, sex ratios, size frequencies, and other biological parameters necessary to help mitigate dredging conflicts in the channel. The Cape Canaveral Sea Turtle Workshop is a cooperative effort to comprehensively present research results of these important studies. I gratefully acknowledge the support of everyone involved in this Workshop, particularly the anonymous team of referees who painstakingly reviewed the manuscripts. The cover illustration was drawn by Jack C. Javech. (PDF file contains 86 pages.)

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Shortnose sturgeon (Acipenser brevirostrum), an endangered species, has experienced a several-fold increase in abundance in the Hudson River in recent decades. This population growth followed a substantial improvement in water quality during the 1970s to a large portion (c. 40%) of the species' summertime nursery area. Age structure and growth were investigated to evaluate the hypothesis that improvements in water quality stimulated population recovery through increased survival of young of the year juveniles. Specimens were captured using gill nets bi-monthly from November 2003 to November 2004 (n = 596). Annuli in fin spine sections were used to generate estimates of sturgeon age. Based upon a marginal increment analysis, annuli were determined to form at an annual rate. Age determinations yielded a catch composed of age 5-30 years for sizes 49-105cm Total Length (n = 554). Individual growth rate (von Bertalanffy coefficients: TL, = 1045mm, K = 0.07) for the population was similar to previous growth estimates within the Hudson River as well as proximal estuaries. Hindcast year-class strengths, based upon a recent stock assessment (Bain et al. 2000) and corrected for gill net mesh selectivity and cumulative mortality indicated high recruitments (28,000-43,000 yearlings)during 1986-1992, which were preceded and succeeded by c.5-year periods of lower recruitment (5,000-1 5,000 yearlings). Recruitment patterns were corroborated by trends in shortnose sturgeon bycatch from a Hudson utilities-sponsored monitoring program. Results indicated that Hudson River shortnose sturgeon abundance increased due to the formation of several strong year-classes occurring about five years subsequent to improved water quality in important nursery and forage habitats in the upper Hudson River estuary. (PDF contains 108 pages.)

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Quantitative data on twaite shad are collected annually in spring and autumn since 1974 by the Demersal Young Fish Survey. Results for occurrence of these anadromous species show that twaite shad has been caught in the entire Wadden Sea area despite of the poorly suited 3-m shrimp beam trawl applied in the survey. Regional differences occur: Only sporadic catches are observed in the northern part of the German Wadden Sea, while more frequent ones occurred southwards and in the East Frisian Islands region. The obvious recent increase of abundance of Alosa fallax in spring allows for a lower ranking in the Red List of Endangered Species, while Allis shad (Alosa alosa) requires the same classification, as it was the never caught during the thirty years of surveys.

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A short review of the actual assessments on the northeast atlantic groundfish stocks of cod, saithe, haddock, redfish and Greenland halibut provided by the ICES „Arctic Fisheries Working Group“is given. All these stocks are presently considered outside safe biological limits. For the first time since 5 years the cod stock is in an endangered situation, because the assessment was to optimistic and the TAC therefore set to high. According to the recent assessments necessary changes in the commercial fishery of the year 1998 off the Nowegian coast and in the Barent-Sea area are discussed. Information on distribution and fishery of cod, haddock, saithe and redfish is given. Biological investigations were carried out onboard the German factory trawler FMS „KIEL“ in January/March and September/ Occtober 1998 in order to collect data of the German fishery in that area. Aspects of length and age distributions, and stomach- and gonad investigation are represented.

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HIGHLIGHTS FOR FY 2008 1. Completed the first of a two-year Gulf sturgeon population study on the Choctawhatchee River, Florida. The sub adult and adult Gulf sturgeon population was estimated at 2,800 fish. 2. Gulf sturgeon eggs were collected at three hard bottom sites in the Apalachicola River, Florida; two sites were previously confirmed spawning areas and one was a newly confirmed spawning area. 3. Documented 55 potential environmental threats to Gulf sturgeon spawning habitat in the Pea River, Florida and Alabama. 4. Assigned the Eglin AFB Road-Stream Crossing Working Group to guide the closure, repair and maintenance of roads and road stream crossings that impact threatened and endangered species. 5. Conducted 81 assessments of fish and stream invertebrates on and in watersheds surrounding Eglin AFB. 6. Provided technical support for the 5-year status review and reclassification proposed rule for the Okaloosa darter. 7. Initiated an intensive population genetic analysis of the Okaloosa darter throughout its range. Tissues from over 200 Okaloosa darters were collected and analyzed. 8. Established a GIS database to serve as a host for data from any sites sampled for mussels in Northeast Gulf of Mexico drainages. 9. Conducted habitat surveys at 115 locations in the Apalachicola River to assess the effects of drought-related mussel mortality and strandings, evaluate habitat conditions, and assess population demography. 10. A land use/aerial imagery threats assessment data analysis was completed for the Chipola River. A total of 266 impoundments/borrow pits and 471 unpaved road crossings were identified among the threats. 11. Okaloosa darters marked with elastomeric dyes were monitored in Mill Creek, Eglin AFB, to determine movement and habitat use following completion of a fish passage project. 3 12. Partners for Fish and Wildlife funded a streambank and riparian restoration project on Econfina Creek consisting of 3,900 feet of streambank fencing to exclude cattle access. One acre of riparian floodplain was planted with native trees. 13. We provided design and on-the-ground assistance for restoring surface hydrology at St. Vincent NWR. The project restored approximately 1.5 miles of tidal stream and 100 acres of wetlands. 14. A study was completed on 11 coastal streams to document large wood debris relationships with fluvial geomorphic characteristics. 15. We developed a Population Viability Analysis model for the fat threeridge mussel to determine current and future risk of extinction. 17. A Gulf Sturgeon Friends Group, “Gulf Sturgeon Preservation Society” was organized in FY 08. 18. Multiple outreach projects were completed to detail aquatic resource conservation needs and opportunities, including National Fishing Week, Earth Day, several festivals and school outreach.

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HIGHLIGHTS FOR FY 2007 1. Completed a three-year Gulf sturgeon population study on the Escambia River, Florida. The population was estimated at 451 fish. 2. Implemented the Gulf Striped Bass Restoration Plan by coordinating the 24th Annual Morone Workshop, leading the technical committee, transporting broodfish, coordinating stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system, and evaluating post-stocking success. 3. Completed a survey to document the extent of aquatic resources, recreational fishing opportunities, and fishery management needs on Department of Defense (DoD) facilities located in Region 4. 4. Continued a project in the Apalachicola River to describe the effects of exceptional drought conditions on freshwater mussel recovery. 5. Initiated a study to locate extant populations of the federally endangered Ochlockonee moccasinshell in the Ochlockonee River Basin. We documented the first live individuals in 14 years. 6. Completed a five-year status review for seven threatened and endangered freshwater mussels in the NEG drainages. 7. Restored Mill Creek to improve habitat for the endangered Okaloosa darter by removing six fish passage barriers and creating approximately 3,000 linear feet of new and regenerated stream channel with floodplain and native vegetation. 8. Completed a fish passage project that connected about 5 miles of habitat in Little Rocky Creek, Eglin Air Force Base, to benefit the Okaloosa darter. 9. Completed a threats analysis to aquatic species in the Chipola River watershed using GIS stream data, aerial imagery, and land cover data. 10. Multiple outreach projects were completed to detail aquatic resource conservation needs and opportunities, including National Fishing Week, Earth Day, several festivals, and school outreach.

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HIGHLIGHTS FOR FY 2006 1. Captured and tagged 475 Gulf sturgeons in five Florida rivers and one bay. 2. Documented Gulf sturgeon marine movement and habitat use in the Gulf of Mexico. 3. Assisted the National Oceanic and Atmospheric Administration (NOAA) with the collection of Gulf sturgeon, implantation of acoustic tags, and monitoring of fish in a study to examine movement patterns and habitat use in Pensacola and Choctawhatchee bays post-Hurricane Ivan. 4. Provided technical assistance to Jon “Bo” Sawyer in completing a study – Summer Resting Areas of the Gulf Sturgeon in the Conecuh/Escambia River System, Alabama-Florida – for acquiring a Degree of Master of Science at Troy University, Alabama. 5. Coordinated tagging and data collection with NOAA observers aboard trawlers while collecting Gulf sturgeon during dredging operations in the coastal Gulf of Mexico. 6. Hosted the 7th Annual Gulf Sturgeon Workshop. 7. Implemented Gulf Striped Bass Restoration Plan by coordinating the 23rd Annual Morone Workshop, leading the technical committee, transporting broodfish, coordinating the stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system, and evaluating post-stocking success. 8. Continued updating and managing the Freshwater Mussel Survey Database, a Geographic Information System (GIS) database, for over 800 unique sites in the Northeast Gulf (NEG) drainages in Alabama (AL), Georgia (GA), and Florida (FL). 9. Formed a recovery implementation team for listed mussels in the ACF river basin and oversaw grant cooperative agreements for 14 listed and candidate freshwater mussels in the NEG watersheds. 10. Initiated a project in the Apalachicola River to relocate mussels stranded as a result of drought conditions, and calculate river flows at which mussels would be exposed. 11. Initiated a project in Sawhatchee Creek, Georgia to determine the status of threatened and endangered (T&E) freshwater mussels and target restoration projects, population assessments, and potential population augmentation to lead toward recovery of the listed species. 12. Initiated a study to determine the age and growth of the endangered fat threeridge mussel (Amblema neislerii). 13. Provided technical assistance to the Panama City Ecological Services office for a biological opinion on the operations of Jim Woodruff Lock and Dam and its effects on the listed species and designated and proposed critical habitat in the Apalachicola River, Florida. 14. Assisted with a multi-State, inter-agency team to develop a management plan to restore the Alabama shad in the ACF river system. 15. Conducted fishery surveys on Tyndall AFB, Florida and Ft. Benning, Georgia and completed a report with recommendations for future recreational fishery needs. 16. Provided fishery technical assistance to four National Wildlife Refuges (NWR) (i.e., Okefenokee NWR, Banks Lake NWR, St. Vincent NWR, and St. Marks NWR). 17. Initiated an Aquatic Resources and Recreation Fishing Survey on Department of Defense facilities located in Region 4. 18. Identified 130 road-stream crossings on Eglin AFB for rehabilitation and elimination of sediment imputs. 19. Continued the Aquatics Monitoring Program at Eglin AFB to assess techniques that determine current status and sustainability of aquatic habitat and develop a measure to determine quality or degradation of habitat. 20. Assisted Eglin AFB Natural Resource managers in revising the installation’s Integrated Natural Resources Management Plan (INRMP) and its associated component plans. 21. Coordinated recovery efforts for the endangered Okaloosa darter including population/life history surveys, stream restoration, and outreach activities. 22. Initiated a comprehensive status review of the Okaloosa darter with analyses performed to assess available habitat, preferred habitats, range expansions/reductions/fragmentations, population size, and probability of extinction. 23. Assisted the Gulf Coastal Plain Ecosystem Partnership and the Florida Fish and Wildlife Conservation Commission (FWC) under a Memorandum of Agreement to develop conservation strategies, implement monitoring and assessment programs, and secure funds for aquatic management programs in six watersheds in northwest Florida and southeast Alabama. 24. Entered into a cooperative agreement with the U.S. Air Force to encourage the conservation and rehabilitation of natural resources at Hurlburt Field, Florida. 25. Multiple outreach projects were completed to detail aquatic resources’ conservation needs and opportunities; including National Fishing Week, Earth Day, several festivals, and school outreach.

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HIGHLIGHTS FOR FY 2005 1. Assisted with a study to assess hurricane impacts to Gulf sturgeon critical foraging habitat. 2. Documented Gulf sturgeon marine movement and habitat use in the Gulf of Mexico. 3. Documented Gulf sturgeon spawning with the collection of fertilized eggs in the Apalachicola River, Florida. 4. Documented Gulf sturgeon spawning with the collection of fertilized eggs in the Yellow River, Florida. 5. Assisted with benthic invertebrate survey at Gulf sturgeon marine foraging grounds. 6. Implemented Gulf Striped Bass Restoration Plan by coordinating the 22nd Annual Morone Workshop, leading the technical committee, transporting broodfish, and coordinating the stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system. 7. Over 87,000 Phase II Gulf striped bass were marked with sequential coded wire tags and stocked in the Apalachicola River. Post-stocking evaluations were conducted at 45 sites in the fall and spring and 8 thermal refuges in the summer. 8. Completed fishery surveys on 4 ponds on Eglin AFB totaling 53 acres, and completed a report with recommendations for future recreational fishery needs. 9. Completed final report for aquatic monitoring at Eglin AFB from 1999 to 2004. 10. Completed a field collection of the endangered Okaloosa darter to be incorporated into a status review to be completed in FY06. 11. Provided technical assistance to the Region 4 National Wildlife Refuge (NWR) program on changes to the fishery conservation targets for the region. Also provided technical assistance to four NWRs (i.e., Okefenokee NWR, Banks Lake NWR, St. Vincent NWR, and St. Marks NWR) relative to hurricanes and recreational fishing. 12. A draft mussel sampling protocol was tested in wadeable streams in Northwest Florida and southwest Georgia, and an associated field guide, poster, and Freshwater Mussel Survey Protocol and Identification workshop were completed in FY05. 13. Implemented recovery plan and candidate conservation actions for 14 listed and candidate freshwater mussels in the Northeast Gulf Watersheds. 14. Initiated or completed multiple stream restoration and watershed management projects. A total of 7.5 stream miles were restored for stream fishes, and 11 miles of coastline were enhanced for sea turtle lighting. A total of 630 acres of wetlands and 2,401 acres of understory habitat were restored. 15. Conducted a watershed assessment to develop a threats analysis for prioritizing restoration, protection, and enhancement to natural resources of Spring Creek, Georgia and Canoe Creek, Florida. 16. Continued the formation of an Unpaved Road Interagency Team of Federal, State, and local agencies in Northwest Florida to promote stream protection and restoration from unpaved road sediment runoff. Began the development of a technical committee agreement. 17. Conducted Alabama Unpaved Road Inventory within the Northeast Gulf Ecosystem. Data collection will be completed during FY06. 18. Finalized the development of two North Florida hydrophysiographic regional curves for use by the Florida Department of Transportation (DOT) and others involved with stream restoration and protection. Initiated the development of the Alabama Coastal Plain Riparian Reference Reach and Regional Curves for use by the Alabama Department of Environmental Management (ADEM). 19. Provided technical assistance in collecting data, analysis, and thesis formulation with Troy University, Alabama, to identify the influence of large woody debris in southeastern coastal plain streams. 20. Completed pre- and post-restoration fish community monitoring at several restoration projects including Big Escambia Creek, Magnolia Creek, and Oyster Lake, Florida. 21. Established a watershed partnership for the Chipola River in Alabama and Florida and expanded development and participation in the Spring Creek Watershed Partnership, Georgia. 22. Continued to identify barriers which inhibit the movement of aquatic species within the Northeast Gulf Ecoregion. 23. Completed a report on road crossing structures in Okaloosa darter streams to guide the closure/repair/maintenance of roads to contribute to recovery of the endangered species. In cooperation with Three Rivers RC&D Council, fish passage sites identified in the report were prioritized for restoration. 24. Monitored Aquatic Nuisance Species in the Apalachicola River and tested the sterility of exotic grass carp. 25. Multiple outreach projects were completed to detail aquatic resources conservation needs and opportunities. Participated in National Fishing Week event, several festivals, and school outreach.

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HIGHLIGHTS FOR FY 2003 1. Continued a 3-year threatened Gulf sturgeon population estimate in the Escambia River, Florida and conducted presence-absence surveys in 4 other Florida river systems and 1 bay. 2. Five juvenile Gulf sturgeon collected, near the mouth of the Choctawhatchee River, Florida, were equipped with sonic tags and monitored while over-wintering in Choctawhatchee Bay. 3. Continued to examine Gulf sturgeon marine habitat use. 4. Implemented Gulf Striped Bass Restoration Plan by coordinating the 20th Annual Morone Workshop, leading the technical committee, transporting broodfish, and coordinating the stocking on the Apalachicola-Chattahoochee-Flint (ACF) river system. 5. Over 73,000 Phase II Gulf striped bass were marked with sequential coded wire tags and stocked in the Apalachicola River. Post-stocking evaluations were conducted at 31 sites. 6. Three stream fisheries assessment s were completed to evaluate the fish community at sites slated for habitat restoration by the Partners for Fish and Wildlife Program (PFW). 7. PFW program identified restoration needs and opportunities for 10 areas. 8. Developed an Unpaved Road Evaluation Handbook. 9. Completed restoration of Chipola River Greenway, Seibenhener Streambank Restoration, Blackwater River State Forest, and Anderson Property. 10. Assessments for fluvial geomorphic conditions for design criteria were completed for 3 projects. 11. Geomorphology in Florida streams initiated development of Rosgen regional curves for Northwest Florida for use by the Florida Department of Transportation. 12. Developed a Memorandum of Understanding between partners for enhancing, protecting, and restoring stream, wetland, and upland habitat in northwest Florida 13. Completed aquatic fauna and fish surveys with new emphasis on integration of data from reach level into watershed and landscape scale and keeping database current. 14. Compliance based sampling of impaired waterbodies on Eglin Air Force Base in conjunction with Florida Department of Environmental Protection for Total Maximum Daily Load development support. 15. Surveyed 20 sites for the federally endangered Okaloosa darter, provided habitat descriptions, worked with partners to implement key recovery tasks and set priorities for restoration. 16. Worked with partners to develop a freshwater mussel survey protocol to provide standard operating procedures for establishing the presence/absence of federally listed mussel species within a Federal project area. 17. GIS database was created to identify all known freshwater mussel records from the northeast Gulf ecosystem. 18. Completed recovery plan for seven freshwater mussels and drafted candidate elevation package for seven additional mussels. Developed proposals to implement recovery plan. 19. Worked with Corps of Engineers and State partners to develop improved reservoir operating policies to benefit both riverine and reservoir fisheries for the ACF river system. 20. Multiple outreach projects were completed to detail aquatic resources conservation opportunities. 21. Multiple stream restoration and watershed management projects initiated or completed (see Appendix A).

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Rasbora tawarensis is an endemic freshwater fish in Lake Laut Tawar, Aceh Province, Indonesia. Unfortunately, its status is regarded a critical endangered with populations decreasing in recent years. To date no information on the spawning activities of the fish are available. Therefore, this study provides a contribution to the. knowledge on reproductive biology of R. tawarensis especially on spawning seasons as well as basic information for conservation of the species. Monthly sampling was conducted from April 2008 to March 2009 by using selective gillnets. The gonadosomatic index, size composition and sex ratio were assessed. The gonadal development was evaluated based on macroscopic and microscopic examinations of the gonads. The gonadosomatic index (GSI) varied between 6.65 to 18.16 in female and 4.94 to 8.56 for male. GSI of the female R. tawarensis was higher in March, September and December indicating the onset of reproductive seasons, the GSI and oocyte size being directly correlated with gonadal development stages. Although, a greater proportion of mature male than female was detected during the study, the sex ratio showed that the overall number of female was higher than male. The ovaries had multiple oocyte size classes at every stage of gonadal development, thus R. tawarensis can be classified as a group synchronous spawner or a fractional multiple spawner. The spawning seasons of R. tawarensis were three times a year and September being the peak of the reproductive season and the female was the predominant sex. This species is classified as a group synchronous spawner. (PDF contains 8 pages)

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This paper is aimed at government, non-government organizations, intergovernmental organizations and the general public as they work toward the development of their individual strategies and action plans. It has been recognized that community-based organizations have a particular relevance to the pursuit of sustainable resource management and may well contribute to the foundations of self-sustenance. Women on Lake Victoria, Tanzania presently face great challenges within the fishery. These include the lack of capital, interference by men, theft of fishing gear, time constraints and socio-cultural problems. In recent years, the fish trading and marketing sectors of the fishery, which have traditionally been dominated by women, have seen large incursions by male entrepreneurs. This move has endangered the role of women within the fishery. This paper focuses on the Tweyambe Fishing Enterprise (TFE), a well-known women's group based in Kasheno village in the Muleba District of Kagera Region in northwestern Tanzania. Inhabitants from the Haya ethnic group who make up some 95% of the population of Kagera Region dominate this village. The TFE has a series of initiatives aimed towards ecologically sound self-development

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Rising global temperatures threaten the survival of many plant and animal species. Having already risen at an unprecedented rate in the past century, temperatures are predicted to rise between 0.3 and 7.5C in North America over the next 100 years (Hawkes et al. 2007). Studies have documented the effects of climate warming on phenology (timing of seasonal activities), with observations of early arrival at breeding grounds, earlier ends to the reproductive season, and delayed autumnal migrations (Pike et al. 2006). In addition, for species not suited to the physiological demands of cold winter temperatures, increasing temperatures could shift tolerable habitats to higher latitudes (Hawkes et al. 2007). More directly, climate warming will impact thermally sensitive species like sea turtles, who exhibit temperature-dependent sexual determination. Temperatures in the middle third of the incubation period determine the sex of sea turtle offspring, with higher temperatures resulting in a greater abundance of female offspring. Consequently, increasing temperatures from climate warming would drastically change the offspring sex ratio (Hawkes et al. 2007). Of the seven extant species of sea turtles, three (leatherback, Kemp’s ridley, and hawksbill) are critically endangered, two (olive ridley and green) are endangered, and one (loggerhead) is threatened. Considering the predicted scenarios of climate warming and the already tenuous status of sea turtle populations, it is essential that efforts are made to understand how increasing temperatures may affect sea turtle populations and how these species might adapt in the face of such changes. In this analysis, I seek to identify the impact of changing climate conditions over the next 50 years on the availability of sea turtle nesting habitat in Florida given predicted changes in temperature and precipitation. I predict that future conditions in Florida will be less suitable for sea turtle nesting during the historic nesting season. This may imply that sea turtles will nest at a different time of year, in more northern latitudes, to a lesser extent, or possibly not at all. It seems likely that changes in temperature and precipitation patterns will alter the distribution of sea turtle nesting locations worldwide, provided that beaches where the conditions are suitable for nesting still exist. Hijmans and Graham (2006) evaluate a range of climate envelope models in terms of their ability to predict species distributions under climate change scenarios. Their results suggested that the choice of species distribution model is dependent on the specifics of each individual study. Fuller et al. (2008) used a maximum entropy approach to model the potential distribution of 11 species in the Arctic Coastal Plain of Alaska under a series of projected climate scenarios. Recently, Pike (in press) developed Maxent models to investigate the impacts of climate change on green sea turtle nest distribution and timing. In each of these studies, a set of environmental predictor variables (including climate variables), for which ‘current’ conditions are available and ‘future’ conditions have been projected, is used in conjunction with species occurrence data to map potential species distribution under the projected conditions. In this study, I will take a similar approach in mapping the potential sea turtle nesting habitat in Florida by developing a Maxent model based on environmental and climate data and projecting the model for future climate data. (PDF contains 5 pages)

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The study assessed qualitatively the threat status of all nigerian freshwater fishes using such criteria as rarity, size at maturity, mode of reproduction, human population density, habitat degradation, pollution and range of each species among others. The biology of 48% (129n) of nigerian freshwater species is not well known. Of the 266 known freshwater fishes, 47 species represented 17% are critically endangered, 15 (5%) are endangered , 8(3%), are vulnerable while 23(8%) are near threatened. The paper suggests increased basic knowledge of threatened species and conservation policy along three lines public awareness, legislation and creation of national parks, aquaria and reserves as measures needed to ensure the conservation of the fishes