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Ex situ management is an important conservation tool that allows the preservation of biological diversity outside natural habitats while supporting survival in the wild. Captive breeding followed by re-introduction is a possible approach for endangered species conservation and preservation of genetic variability. The Cayman Turtle Centre Ltd was established in 1968 to market green turtle (Chelonia mydas) meat and other products and replenish wild populations, thought to be locally extirpated, through captive breeding. We evaluated the effects of this re-introduction programmme using molecular markers (13 microsatellites, 800-bp D-loop and simple tandem repeat mitochondrial DNA sequences) from captive breeders (N = 257) and wild nesting females (N = 57) (sampling period: 2013-2015). We divided the captive breeders into three groups: founders (from the original stock), and then two subdivisions of F1 individuals corresponding to two different management strategies, cohort 1995 ("C1995") and multicohort F1 ("MCF1"). Loss of genetic variability and increased relatedness was observed in the captive stock over time. We found no significant differences in diversity among captive and wild groups, and similar or higher levels of haplotype variability when compared to other natural populations. Using parentage and sibship assignment, we determined that 90% of the wild individuals were related to the captive stock. Our results suggest a strong impact of the re-introduction programmme on the present recovery of the wild green turtle population nesting in the Cayman Islands. Moreover, genetic relatedness analyses of captive populations are necessary to improve future management actions to maintain genetic diversity in the long term and avoid inbreeding depression.

Given differing trajectories of sea turtle populations worldwide, there is a need to assess and report long-term population trends and determine which conservation strategies are effective. In this study, we report on sea turtle nest monitoring in the Cayman Islands over a 22-year period. We found that green (Chelonia mydas) and loggerhead (Caretta caretta) nest numbers increased significantly across the three islands since monitoring began in 1998, but that hawksbill nest numbers remained low with a maximum of 13 nests recorded in a season. Comparing the first 5 years of nest numbers to the most recent 5 years, the greatest percentage increase in green turtle nests was in Grand Cayman from 82 to 1,005 nests (1,126%), whereas the greatest percentage increase for loggerhead turtle nests was in Little Cayman from 10 to 290 nests (3,800%). A captive breeding operation contributed to the increase in the Grand Cayman green turtle population, however, loggerhead turtles were never captive-bred, and these populations began to increase after a legal traditional turtle fishery became inactive in 2008. Although both species have shown significant signs of recovery, populations remain at a fragment of their historical level and are vulnerable to threats. Illegal harvesting occurs to this day, with multiple females taken from nesting beaches each year. For nests and hatchlings, threats include artificial lighting on nesting beaches, causing hatchlings to misorient away from the sea, and inundation of nests by seawater reducing hatch success. The impacts of lighting were found to increase over the monitoring period. Spatial data on nest distribution was used to identify critical nesting habitat for green and loggerhead turtles and is used by the Cayman Islands Department of Environment to facilitate remediation of threats related to beachside development and for targeted future management efforts.

Although sea turtles have received substantial focus worldwide, research on the immature life stages is still relatively limited. The latter is of particular importance, given that a large proportion of sea turtle populations comprises immature individuals. We set out to identify knowledge gaps and identify the main barriers hindering research in this field. We analyzed the perceptions of sea turtle experts through an online survey which gathered their opinions on the current state of affairs on immature sea turtle research, including species and regions in need of further study, priority research questions, and barriers that have interfered with the advancement of research. Our gap analysis indicates that studies on immature leatherback Dermochelys coriacea and hawksbill Eretmochelys imbricata turtles are lacking, as are studies on all species based in the Indian, South Pacific, and South Atlantic Oceans. Experts also perceived that studies in population ecology, namely on survivorship and demography, and habitat use/behavior, are needed to advance the state of knowledge on immature sea turtles. Our survey findings indicate the need for more interdisciplinary research, collaborative efforts (e.g. data-sharing, joint field activities), and improved communication among researchers, funding bodies, stakeholders, and decision-makers. Fil: Wildermann, Natalie E.. Florida State University; Estados Unidos Fil: Gredzens, Christian. Florida State University; Estados Unidos Fil: Avens, Larisa. National Ocean And Atmospheric Administration; Estados Unidos Fil: Barrios Garrido, Héctor A.. Universidad del Zulia; Venezuela. Florida State University; Estados Unidos Fil: Bell, Ian. Aquatic Species Program. Conservation And Biodiversity Operations Branch; Australia Fil: Blumenthal, Janice. Cayman Islands Department Of Environment; Islas Caimán Fil: Bolten, Alan B.. University of Florida; Estados Unidos Fil: McNeill, Joanne Braun. National Ocean And Atmospheric Administration; Estados Unidos Fil: Casale, Paolo. Università degli Studi di Pisa; Italia Fil: Di Domenico, Maikon. Universidade Federal do Paraná; Brasil Fil: Domit, Camila. Universidade Federal do Paraná; Brasil Fil: Epperly, Sheryan P.. National Ocean And Atmospheric Administration; Estados Unidos Fil: Godfrey, Matthew H.. North Carolina Wildlife Resources Commission; Estados Unidos. University of North Carolina; Estados Unidos. University of Duke; Estados Unidos Fil: Godley, Brendan J.. University of Exeter; Reino Unido Fil: González Carman, Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Subsede Instituto Nacional de Investigación y Desarrollo Pesquero; Argentina Fil: Hamann, Mark. James Cook University; Australia Fil: Hart, Kristen M.. United States Geological Survey; Estados Unidos Fil: Ishihara, Takashi. Sea Turtle Association of Japan; Japón. Suma Aqualife Park; Japón Fil: Mansfield, Kate L.. University Of Central Florida; Estados Unidos Fil: Metz, Tasha L.. No especifica; Fil: Miller, Jeffrey D.. No especifica; Fil: Pilcher, Nicolas J.. Marine Research Foundation; Malasia Fil: Read, Mark A.. Great Barrier Reef Marine Park Authority; Australia Fil: Sasso, Christopher. National Ocean And Atmospheric Administration; Estados Unidos Fil: Seminoff, Jeffrey A.. National Ocean And Atmospheric Administration; Estados Unidos Fil: Seney, Erin E.. University Of Central Florida; Estados Unidos Fil: Williard, Amanda Southwood. University of North Carolina; Estados Unidos Fil: Tomás, Jesús. Universidad de Valencia; España Fil: Vélez Rubio, Gabriela M.. Universidad de la República; Uruguay. Karumbé Ngo; Uruguay Fil: Ware, Matthew. Florida State University; Estados Unidos Fil: Jessica L. Williams. Tartarugas para o Amanhã; Mozambique Fil: Wyneken, Jeanette. Florida Atlantic University; Estados Unidos Fil: Fuentes, Mariana M. P. B. Florida State University; Estados Unidos

Somatic growth is an integrated, individual-based response to environmental conditions, especially in ectotherms. Growth dynamics of large, mobile animals are particularly useful as bio-indicators of environmental change at regional scales. We assembled growth rate data from throughout the West Atlantic for green turtles, Chelonia mydas, which are long-lived, highly migratory, primarily herbivorous mega-consumers that may migrate over hundreds to thousands of kilometers. Our dataset, the largest ever compiled for sea turtles, has 9690 growth increments from 30 sites from Bermuda to Uruguay from 1973 to 2015. Using generalized additive mixed models, we evaluated covariates that could affect growth rates; body size, diet, and year have significant effects on growth. Growth increases in early years until 1999, then declines by 26% to 2015. The temporal (year) effect is of particular interest because two carnivorous species of sea turtles-hawksbills, Eretmochelys imbricata, and loggerheads, Caretta caretta-exhibited similar significant declines in growth rates starting in 1997 in the West Atlantic, based on previous studies. These synchronous declines in productivity among three sea turtle species across a trophic spectrum provide strong evidence that an ecological regime shift (ERS) in the Atlantic is driving growth dynamics. The ERS resulted from a synergy of the 1997/1998 El Niño Southern Oscillation (ENSO)-the strongest on record-combined with an unprecedented warming rate over the last two to three decades. Further support is provided by the strong correlations between annualized mean growth rates of green turtles and both sea surface temperatures (SST) in the West Atlantic for years of declining growth rates (r = -.94) and the Multivariate ENSO Index (MEI) for all years (r = .74). Granger-causality analysis also supports the latter finding. We discuss multiple stressors that could reinforce and prolong the effect of the ERS. This study demonstrates the importance of region-wide collaborations.

Unsustainable wildlife trade affects biodiversity and the livelihoods of communities dependent upon those resources. Wildlife farming has been proposed to promote sustainable trade, but characterizing markets and understanding consumer behavior remain neglected but essential steps in the design and evaluation of such operations. We used sea turtle trade in the Cayman Islands, where turtles have been farm raised for human consumption for almost 50 years, as a case study to explore consumer preferences toward wild-sourced (illegal) and farmed (legal) products and potential conservation implications. Combining methods innovatively (including indirect questioning and choice experiments), we conducted a nationwide trade assessment through in-person interviews from September to December 2014. Households were randomly selected using disproportionate stratified sampling, and responses were weighted based on district population size. We approached 597 individuals, of which 37 (6.2%) refused to participate. Although 30% of households had consumed turtle in the previous 12 months, the purchase and consumption of wild products was rare (e.g., 64-742 resident households consumed wild turtle meat [i.e., 0.3-3.5% of households] but represented a large threat to wild turtles in the area due to their reduced populations). Differences among groups of consumers were marked, as identified through choice experiments, and price and source of product played important roles in their decisions. Despite the long-term practice of farming turtles, 13.5% of consumers showed a strong preference for wild products, which demonstrates the limitations of wildlife farming as a single tool for sustainable wildlife trade. By using a combination of indirect questioning, choice experiments, and sales data to investigate demand for wildlife products, we obtained insights about consumer behavior that can be used to develop conservation-demand-focused initiatives. Lack of data from long-term social-ecological assessments hinders the evaluation of and learning from wildlife farming. This information is key to understanding under which conditions different interventions (e.g., bans, wildlife farming, social marketing) are likely to succeed.

Somatic growth dynamics are an integrated response to environmental conditions. Hawksbill sea turtles (Eretmochelys imbricata) are long‐lived, major consumers in coral reef habitats that move over broad geographic areas (hundreds to thousands of kilometers). We evaluated spatio‐temporal effects on hawksbill growth dynamics over a 33‐yr period and 24 study sites throughout the West Atlantic and explored relationships between growth dynamics and climate indices. We compiled the largest ever data set on somatic growth rates for hawksbills – 3541 growth increments from 1980 to 2013. Using generalized additive mixed model analyses, we evaluated 10 covariates, including spatial and temporal variation, that could affect growth rates. Growth rates throughout the region responded similarly over space and time. The lack of a spatial effect or spatio‐temporal interaction and the very strong temporal effect reveal that growth rates in West Atlantic hawksbills are likely driven by region‐wide forces. Between 1997 and 2013, mean growth rates declined significantly and steadily by 18%. Regional climate indices have significant relationships with annual growth rates with 0‐ or 1‐yr lags: positive with the Multivariate El Niño Southern Oscillation Index (correlation = 0.99) and negative with Caribbean sea surface temperature (correlation = −0.85). Declines in growth rates between 1997 and 2013 throughout the West Atlantic most likely resulted from warming waters through indirect negative effects on foraging resources of hawksbills. These climatic influences are complex. With increasing temperatures, trajectories of decline of coral cover and availability in reef habitats of major prey species of hawksbills are not parallel. Knowledge of how choice of foraging habitats, prey selection, and prey abundance are affected by warming water temperatures is needed to understand how climate change will affect productivity of consumers that live in association with coral reefs.

The advent of telemetry has improved knowledge of the spatio-temporal distribution of marine species of conservation concern. Among the sea turtles, the movements of the hawksbill turtle Eretmochelys imbricata are among the least well described. We tracked 10 adult female hawksbill turtles by satellite after nesting in the Dominican Republic (DR) and describe a dichotomy in patterns of movement: some (n = 2) turtles remained in the DR, while others migrated to waters off Honduras and Nicaragua (n = 5) and the Bahamas (n = 1). Transmitters on 2 turtles failed during migration, before they reached their final foraging grounds. We present results from long tracking durations for 3 turtles, including 3 entire remigration intervals, high- lighting foraging ground and nest-site fidelity. Threats to hawksbill turtles are not well docu- mented for Nicaragua or neighbouring Honduras and represent a major information gap. We sug- gest that directing conservation efforts to regionally important foraging areas, such as those in Nicaragua, and strengthening national conservation in each nation with significant hawksbill nesting offers a clear way forward for the conservation of hawksbill turtles in the region.

Tracking fine-scale movements in relation to threats is fundamental to the management of exploited marine species, yet there is considerable difficulty associated with gathering such data at sea. By combining a capture-recapture study with deployment of time-depth recorders (TDRs) and ultrasonic tags, we elucidated distribution and daily movements of juvenile green turtles Chelonia mydas exposed to a legal marine turtle fishery in the Cayman Islands. For instrumented turtles, dis- tinct diel activity patterns were observed: dives during the day were shorter and more active than those at night, implying diurnal foraging and nocturnal resting. Spatially, while capture and recap- ture locations suggested fidelity to a shallow lagoon, when turtles were fitted with TDRs and ultra- sonic tags we demonstrated that they regularly moved out of the lagoon and onto the reef, where they could legally be captured in the marine turtle fishery. Our results are thus novel and valuable in a management context in that we demonstrated that seemingly protected aggregations of juvenile green turtles within a lagoon were, in fact, exposed to legal capture on a near-daily basis. This emphasizes the importance of assessing diel activity patterns of juvenile marine turtles, particularly with respect to directed take and other threats.

Acquiring knowledge of the spatial ecology of many aquatic species, particularly their juvenile life stages, is challenging when they are small in size; this limits the attachment of tracking devices that routinely provide spatially explicit information on larger juveniles and adults. Using depth utilisation data gathered by time-depth recorders, we inferred patterns of habitat utilisation of juvenile hawksbill turtles Eretmochelys imbricata occupying a shallow reef system in the Caribbean. Hawksbill turtles (n = 9, curved carapace length = 42.3 ± 9.7 cm, range = 27.7 to 60.0 cm) demon- strated diel patterns of behaviour, with greater activity and shorter dives during the day (mean dura- tion = 7.5 ± 5.0 min, range = 2.6 to 34.4 min) and longer, less active dives during the night (mean dura- tion = 16.6 ± 12.0 min, range = 2.5 to 61.5 min). A level of fidelity to sites facilitated recaptures (mean minimum straight-line distance from release of TDR-equipped turtles to their subsequent recapture locations = 0.9 ± 0.9 km, range = 0.01 to 2.3 km), but recapture success after 130 h, over a 43 d period, was relatively low: of 19 individuals instrumented, 9 were recaptured. From depth records, i.e. max- imum depths achieved, it was clear that some recaptured individuals moved considerably during the monitoring period; 3 individuals moved to deeper waters, with minimum possible straight-line move- ment distances from their capture sites of 3.7 to 9.2 km. These findings emphasize the likely influence of habitat structure on site fidelity and further highlight that data from traditional capture-mark- recapture studies could lead to an underestimation of home-range size.

Where mechanisms inherent within the biology of a species affect individual fitness at low density, demographic-scale depensation may occur, hastening further decline and leading ultimately to population extirpation and species extinction. Reduction in fertility at low population densities has been identified in marine and terrestrial species. Using data on hatch success and hatchling-emergence success as proxies for fertilization success, we conducted a global meta-analysis of data from breeding aggregations of green turtles (Chelonia mydas) and loggerhead turtles (Caretta caretta). We found that there has been no reduction in fertility in small nesting aggregations in either of these species worldwide. We considered mechanisms within the mating strategies and reproductive biology of marine turtles that may allow for novel genetic input and facilitate enhanced gene flow among rookeries. Behavioral reproductive mechanisms, such as natal philopatry and polyandry, may mitigate potential impacts of depensation and contribute to the resilience of these species.

Despite intense interest in conservation of marine turtles, spatial ecology during the oceanic juvenile phase remains relatively unknown. Here, we used mixed stock analysis and examination of oceanic drift to elucidate movements of hawksbill turtles (Eretmochelys imbricata) and address management implications within the Caribbean. Among samples collected from 92 neritic juvenile hawksbills in the Cayman Islands we detected 11 mtDNA control region haplotypes. To estimate contributions to the aggregation, we performed 'many-to-many' mixed stock analysis, incorporating published hawksbill genetic and population data. The Cayman Islands aggregation represents a diverse mixed stock: potentially contributing source rookeries spanned the Caribbean basin, delineating a scale of recruitment of 200-2500 km. As hawksbills undergo an extended phase of oceanic dispersal, ocean currents may drive patterns of genetic diversity observed on foraging aggregations. Therefore, using high-resolution Aviso ocean current data, we modelled movement of particles representing passively drifting oceanic juvenile hawksbills. Putative distribution patterns varied markedly by origin: particles from many rookeries were broadly distributed across the region, while others would appear to become entrained in local gyres. Overall, we detected a significant correlation between genetic profiles of foraging aggregations and patterns of particle distribution produced by a hatchling drift model (Mantel test, r = 0.77, P < 0.001; linear regression, r = 0.83, P < 0.001). Our results indicate that although there is a high degree of mixing across the Caribbean (a 'turtle soup'), current patterns play a substantial role in determining genetic structure of foraging aggregations (forming turtle groups). Thus, for marine turtles and other widely distributed marine species, integration of genetic and oceanographic data may enhance understanding of population connectivity and management requirements.

We present results of an inwater research program focusing on basic ecology of juvenile hawksbill turtles (Eretmochelys imbricata) in the Cayman Islands. We made 206 captures of 135 hawksbills in Little Cayman and 103 captures of 97 hawksbills in Grand Cayman. The Cayman Islands aggregation demonstrated a broad size distribution (20.5–62.6 cm straight carapace length), slow growth rate (3.0 ± 0.9 cm/y), and multiple recaptures, suggesting long-term residence in some individuals. Demonstrated home range was small (mean distance from capture to recapture 545 ± 514 m, range 2–2080 m); although, an international tag return suggested a long-range developmental migration. Vertical features provided important habitat in Little Cayman, and larger turtles were generally captured in deeper waters. Behavior at sighting varied by habitat: resting, swimming, and feeding were observed in coral reef, reef wall, and hardbottom colonized by sponges and gorgonians, and resting was frequently observed in uncolonize...

Here we present data from a 26-month program "Caribbean Turtle Watch," initiated as part of the "Turtles in the Caribbean Overseas Territories" (TCOT) program and designed to harness recreational divers to assess in-water populations of marine turtles in the Cayman Islands. We recorded 521 dives in Grand Cayman and Little Cayman between September 1, 2002 and November 29, 2003. Data, presented as the mean number of turtles sighted per dive, provide insight into spatiotemporal patterns of sightings as a proxy of abundance. Widespread sightings were recorded of two marine turtle species, green turtles Chelonia mydas and hawksbill turtles Eretmochelys imbricata, around both islands. There was no obvious relationship between the existence of Marine Protected Areas (MPAs) and the abundance of turtle sightings. Diving is allowed in Marine Park Zones and dive pressure may impact overall habitat quality in these areas. The vast majority of sightings of both species (94% in each case) were considered to be juvenile or subadults. While turtle sighting potential was not a major influence on dive site choice, actual turtle sighting greatly enhanced dive enjoyment. Spatiotemporal and morphological analyses of data collected by volunteers compared favorably with those based on data collected by scientists. This technique is transferable to other countries and may hold particular value in areas where resources assigned to marine turtle research are low.

As historically abundant spongivores, hawksbill turtles Eretmochelys imbricata likely played a key ecological role on coral reefs. However, coral reefs are now experiencing global declines and many hawksbill populations are critically reduced. For endangered species, tracking movement has been recognized as fundamental to management. Since movements in marine vertebrates encompass three dimensions, evaluation of diving behavior and range is required to characterize marine turtle habitat. In this study, habitat use of hawksbill turtles on a Caribbean coral reef was elucidated by quantifying diel depth utilization and movements in relation to the boundaries of marine protected areas. Time depth recorders (TDRs) and ultrasonic tags were deployed on 21 Cayman Islands hawksbills, ranging in size from 26.4 to 58.4 cm straight carapace length. Study animals displayed pronounced diel patterns of diurnal activity and nocturnal resting, where diurnal dives were significantly shorter, deeper, and more active. Mean diurnal dive depth (±SD) was 8 ± 5 m, range 2–20 m, mean nocturnal dive depth was 5 ± 5 m, range 1–14 m, and maximum diurnal dive depth was 43 ± 27 m, range 7–91 m. Larger individuals performed significantly longer dives. Body mass was significantly correlated with mean dive depth for nocturnal but not diurnal dives. However, maximum diurnal dive depth was significantly correlated with body mass, suggesting partitioning of vertical habitat by size. Thus, variable dive capacity may reduce intraspecific competition and provide resistance to degradation in shallow habitats. Larger hawksbills may also represent important predators on deep reefs, creating a broad ecological footprint over a range of depths.

The use of satellite tracking for the fundamental and applied study of marine turtles began in the 1980s but has undergone rapid growth in recent years. To provide a background against which to judge the past success and future directions of these research efforts we carried out a com- prehensive review of over 130 scientific papers on the use of this technique in this taxon. We show how satellite tracking has changed over time as well as outlining biases in spatial, species and life- stage coverage. Descriptions of migration routes and other habitats have offered novel insights into the basic life history patterns of some species, highlighted focal areas for conservation and reinforced the multi-national nature of the stakeholders of many populations. In foraging areas, knowledge is growing as to how animals move within dynamic seascapes, thus facilitating our understanding of 3-dimensional habitat use and seasonal patterns of behaviour. More experimental approaches have elucidated navigational capabilities and post-release survival following fisheries interaction and long-term captivity. In addition, through the Internet and other media, satellite tracking appears to have been effective in engaging public attention in many countries. Finally, we discuss why the use of the technique has increased so markedly over time and point out key areas of concern that we feel should be addressed by the community of researchers and donors who focus on sea turtles.

Historically, nesting marine turtles were abundant in the Cayman Islands and were an integral part of the economy and culture. Today, nesting of loggerhead turtle Caretta caretta and green turtles Chelonia mydas takes place at very low levels. Hawksbill Eretmochelys imbricata nesting has not been recorded since 1999. We overview highly detailed monitoring data gathered over a 6-year period allowing insight into the magnitude and spatial and temporal patterns of marine turtle nesting, cost-effectiveness of monitoring such reduced populations, impacts of development on reproductive success and current threats to the recovery of the population. Nesting is diffuse and widely distributed for both nesting species on Grand and Little Cayman. Modelled nesting detection profiles for Grand Cayman show that in order to maintain data resolution, most sandy coastline must be surveyed throughout each season. However, in Little Cayman it may be possible to reduce effort. Legal take of adults and illegal take of eggs may be significantly impacting the remaining population. Surprisingly, we observed no significant correlation between density of coastal development and clutch density, adult emergence success or hatching success for either species. A significant relationship exists however, between density of coastal development and incidence of misorientation events in loggerhead hatchlings but not in green turtle hatchlings. Effective protection of known nesting habitat and the elimination of exploitation of remaining adults and eggs within the population are critical to its recovery.

We present detailed results of a satellite tracking project following 10 adult female tur- tles from the Cayman Islands, thought to have once been one of the world's largest rookeries. By tracking the movements of 7 green turtles Chelonia mydas and 3 loggerhead turtles Caretta caretta from now critically reduced rookeries we defined key habitats for internesting movement, migration, and foraging in a range of Caribbean jurisdictions. Turtles tracked from the Cayman Islands traveled to foraging grounds in Belize, Guatemala, Honduras, Mexico, Nicaragua and the USA. This range encompasses a >2000 km stretch of Caribbean coastline and the Florida Keys, highlighting the need for international cooperation in identifying and mitigating foraging ground threats. For one of the green turtles, foraging site fidelity was elucidated over the course of two reproductive seasons, and oceanic internesting intervals/post-nesting oceanic circles were defined for the first time in Atlantic loggerhead turtles. In addition to fundamental and applied insights into the biology of the 2 species, this research elucidates geographic scale for potential ecological effects of past decimation of rook- eries in the Cayman Islands and highlights the effectiveness of community efforts in support of conservation research.

Many marine turtle populations are smaller than they once were, having been exploited at varying levels since prehistory. However, in areas where exploitation of adults has been substan- tially reduced or halted, increases in local nesting populations of several species have been shown. There is a paucity of published information on catch rates, methodologies, target species and size classes in small scale marine turtle fisheries. In the Cayman Islands a legal, highly regulated turtle fishery exists; laws regarding turtle protection regulate seasonality, capture location and method, size class, and levels of take via a licensing system. Licenses have only been issued to 'traditional' fishermen and will not be issued to other individuals in the future. Analysis of fishery data from legally captured animals (n = 27) shows that all turtles reported as captured were either adults or very large juveniles, and many were captured during periods when adults were likely to have been in the waters of the Cayman Islands to breed. We conclude that, given the critically small size of the local nesting populations, it is possible that this directed take, although at very low levels in regional terms, may impede the local population recovery sought through other conservation and manage- ment steps being taken in the Cayman Islands.

Reduction in the use of fallow in traditional wheat-fallow cropping systems, along with other management changes such as reduced tillage, raise questions about nutrient management, particularly phosphorus (P) management, in such soils. Phosphorus is focused on because of its low soil mobility and it

The Cayman islands are three small low-lying subtropical islands in the NW Caribbean. The islands are tips of an underwater mountain chain and have a very narrow coastal shelf, usually of less than 1 km wide, which support considerable reef development. The major sublittoral habitats are coral reefs, lagoons, seagrass beds and mangroves, and fringing reefs shelter large areas of seagrasses and mangroves, the latter being important nursery areas also. There is a high diversity of marine invertebrates, with several molluscs and crustaceans providing commercially significant species. However, substantial recent developments have increased pressures on the marine systems, added to which more recently are stressors resulting from climate change. The islands are hit by hurricanes about once every 10 years, and suffer near-misses four times more often, which greatly affects these habitats. There are a number of different categories of Marine Protected Areas but even so, due to a number of direct anthropogenic stressors as well, coral cover has declined from 25 % to about 11 % over the past 15 years. Physical destruction from shipping and recreational boating has contributed significantly to this, as have various forms of pollution, dredging and shoreline construction, and poaching. The Marine Protected Area system is being reviewed, with specific measures to manage Grouper spawning aggregation sites, and a culling programme is underway in an attempt to control the invasive lionfish which pose the most recent threat to the coral reef fish communities.

The four islands of Cayman Islands are among the most isolated in the West Indies. They support 25 native species of amphibians and reptiles. Fifteen additional species have been deliberately or accidently introduced. The immediate source for 11 of the 15 is the United States. Eight of the 15 have become established. There have been two introductions in which both the source and target islands are in the Cayman Islands, one successful and the other a failure. Eleven native species have been evaluated with respect to CITES and/or IUCN. Nine species have not been evaluated and some of these may be found to warrant listing. Seventeen species, some with multiple subspecies, are endemic to the Cayman Islands. Threats to the native species of the Cayman Islands include habitat modification or destruction, over-exploitation, introduced species, and the effects of anthropogenic global climate change. Conservation actions are discussed, emphasizing marine turtles and Cyclura lewisi, as is legal protection afforded the herpetofauna.

Legumes obtain a substantial portion of their nitrogen (N) from symbiotic N2 fixation in root nodules. The glutamine synthetase (GS, EC 6.3.1.2)/glutamate synthase (GOGAT) cycle is responsible for the initial N assimilation. This report describes the analysis of a transgenic alfalfa (Medicago sativa L.) line containing an antisense NADH-GOGAT (EC 1.4.1.14) under the control of the nodule-enhanced aspartate amino-transferase (AAT-2) promoter. In one transgenic line, NADH-GOGAT enzyme activity was reduced to approximately 50%, with a corresponding reduction in protein and mRNA. The transcript abundance for cytosolic GS, ferredoxin-dependent GOGAT (EC 1.4.7.1), AAT-2 (EC 2.6.1.1), asparagine synthase (EC 6.3.5.4), and phosphoenolpyruvate carboxylase (PEPC, EC 4.1.1.31) were unaffected, as were enzyme activities for AAT, PEPC and GS. Antisense NADH-GOGAT plants grown under symbiotic conditions were moderately chlorotic and reduced in growth and N content, even though symbiotic N2 fixation was not significantly reduced. The addition of nitrate relieved the chlorosis and restored growth and N content. Surprisingly, the antisense NADH-GOGAT plants were male sterile resulting from inviable pollen. A reduction in NADH-GOGAT enzyme activity and transcript abundance in the antisense plants was measured during the early stages of flower development. Inheritance of the transgene was stable and resulted in progeny with a range of NADH-GOGAT activity. These data indicate that NADH-GOGAT plays a critical role in the assimilation of symbiotically fixed N and during pollen development.