Sea turtles face many threats to their populations globally. Loggerhead sea turtles (Caretta caretta) and green sea turtles (Chelonia mydas) are listed by the International Union for the Conservation of Nature Red List as Endangered. In Florida, loggerhead and green sea turtles nest along the coastline during April-September. Mechanical beach cleaning is an aesthetic service performed daily on some beaches in Florida to clean the wrack line and/or the entire beach of debris. Alterations made to beaches by methods such as mechanical beach cleaning have the potential to impact sea turtle nesting, hatching, and emergence success. Generalized linear mixed models were performed to investigate the impacts of mechanical beach cleaning on nesting, hatching and emergence success of loggerhead and green turtles from 1997-2015 in Broward County, Florida. The results showed mechanical beach cleaning had an effect on nesting success, however, hatching and emergence success were not affected by mechanical beach cleaning. These results indicate that mechanical beach cleaning cannot solely be used to determine sea turtle management or conservation guidelines in Broward County.

<p dir="ltr">The Leatherback Sea Turtle (<i>Dermochelys coriacea</i>) is a globally vulnerable species suffering from declining populations due to anthropogenic pressures. There are seven recognized Leatherback Sea Turtle regional management units; however, the Southeast Atlantic unit is considered data deficient. Bioko Island, Equatorial Guinea, is a primary nesting rookery for the Southeast Atlantic regional management unit and has some of the world’s highest numbers of nesting Leatherback Sea Turtles. Despite Bioko Island’s importance to the species, little is known about the nesting ecology or post-nesting migratory movement and behaviors of its nesting Leatherback Sea Turtles. Here, I present the findings of two individual research projects on the nesting ecology of Leatherback Sea Turtles on Bioko Island. First, I explored the long-term clutch success rates (i.e., hatching success and emergence success) of <i>in situ</i> Leatherback Sea Turtle nests on Bioko and searched for associated variables. I found significant spatiotemporal variation over nine nesting seasons, likely driven by individual beach characteristics rather than regional climate patterns. Secondly, I described a novel effort to use solar-reliant towable transmitters to track the post-nesting migratory movements and behaviors of Leatherback Sea Turtles nesting on Bioko Island. With the results from each project, I make recommendations to further the current conservation and research initiatives of Leatherback Sea Turtles.</p>

The Wilson’s Plover (Charadrius wilsonia) is a species of concern in most southeastern U.S. coastal states, where it breeds and winters. The U.S. Shorebird Conservation Plan listed this species as a Species of High Concern (Prioritization Category 4), and the U.S. Fish and Wildlife Service has designated it as a Bird of Conservation Concern (BCC). Despite its conservation status, Wilson’s Plover population trends are poorly understood and little research has been conducted examining habitat factors affecting this species’ breeding and foraging ecology. I collected Wilson’s Plover demographic data and explored which habitat characteristics influenced breeding success and foraging site selection among three coastal habitat types (i.e. fiddler crab (Uca spp.) mud flats, beach front, and interdune sand flats) at Onslow Beach, Marine Corps Base Camp Lejeune, North Carolina, 2008-2009. I observed little difference between years in nest success (≥ 1 egg hatched), failure, and overall nest survival. The majority of nest failures were caused by mammalian predators. For those nests that hatched successfully, greater proportions were located in clumped vegetation than on bare ground or sparsely vegetated areas. In-season chick survival for both years was higher for nests that hatched earlier in the season, and for nests farthest from the broods’ final foraging territory. Productivity estimates (chicks fledged per breeding pair) were not significantly different between years (0.88 ± 0.26 fledged/pair in 2008, 1.00 ± 0.25 fledged/pair in 2009) despite a shift in foraging behavior, possibly related to habitat alterations and availability in 2009. My findings indicate that Wilson’s Plover adults and broods were flexible in establishing final foraging territories; in 2008 all final brood foraging territories were on fiddler flats while in 2009, final foraging territories were sometimes split between fiddler flats, beach front, and interdune sand flats. For those Wilson’s Plovers establishing territories on fiddler flats, area of the flat was the most important feature explaining use versus non-use of a particular flat; area ≥ 1250 m² was preferred. Close proximity to water and vegetative cover were also important habitat features in foraging site selection on fiddler crab mud flats, and in all habitat types combined. My findings will directly contribute to population and habitat research goals outlined in the U.S. Shorebird Plan and will supplement limited data about foraging and habitat use related to Wilson’s Plover breeding ecology. / Master of Science

O presente estudo avalia como a estrutura e a produção da comunidade de copépodes pelágicos da plataforma interna ao largo de Ubatuba (SP, Brasil) responderam às variações ambientais durante o período de julho de 2005 a junho de 2008. Durante estes três anos, a produção secundária dos copépodes foi estudada por meio da aplicação de modelos empíricos de crescimento e de estimativas de crescimento peso-específico obtidas através de experimentos de produção de ovos. Aspectos reprodutivos de 16 espécies de copépodes (9 calanóides, 3 ciclopóides e 4 harpacticóides) foram analisados neste período, através de experimentos de incubação e de métodos indiretos de obtenção de taxas de produção e viabilidade dos ovos. A comunidade de copépodes esteve representada por 70 espécies e foi caracterizada por altos valores de riqueza, diversidade e eqüitabilidade. Os copépodes apresentaram grande variabilidade nos valores médios de densidade (4726 ± 3711 ind. m-3) e de biomassa (7,42 ± 5,64 mg C m-3) e foram dominados por espécies de pequeno porte (< 1000 µm), destacando-se as fêmeas adultas de Oncaea waldemari e os copepoditos imaturos de paracalanídeos e clausocalanídeos. Quando comparada com outros ambientes tropicais e subtropicais, a região estudada apresentou valores elevados de densidade e biomassa. Da mesma maneira, a produção secundária média apresentou variabilidade temporal elevada (1,13 ± 1,11 mg C m-3 dia-1), com uma importante contribuição dos copepoditos imaturos de espécies dispersoras de ovos. No geral, os valores médios registrados foram considerados altos quando comparado com outros ambientes tropicais e subtropicais, embora a razão Produção/Biomassa média tenha sido similar às registradas nestes locais. A intrusão periódica da ACAS parece ter sido a principal responsável pelas alterações observadas na estrutura e produção da comunidade. A maioria dos meses não influenciados pela ACAS apresentou valores de densidade, biomassa e produção inferiores às respectivas médias. Entretanto, os resultados observados sugerem que as flutuações da comunidade de copépodes podem responder não apenas à intrusão da ACAS, mas também a uma complexa conjunção de fatores, incluindo as próprias relações inter e intra-específicas. Com relação à reprodução, as espécies dispersoras de ovos apresentaram taxas médias de produção de ovos similares às obtidas em outras regiões tropicais e subtropicais, enquanto que as retentoras apresentaram valores levemente inferiores. Entretanto, foram registrados picos ocasionais de produção destas últimas espécies, sugerindo que estes copépodes possuem estratégias que compensam os meses de baixa produtividade. A reprodução de algumas espécies analisadas parece ser associada a fatores intra-específicos, tais como o tamanho dos ovos e a razão entre machos e fêmeas. Além disso, as espécies dispersoras analisadas são provavelmente influenciadas pela temperatura e pelo alimento. A relação entre os tamanhos e pesos de fêmeas e ovos de 32 espécies de copépodes pelágicos mostrou que a variabilidade interespecífica observada nessas proporções é similar à tendência observada para espécies de altas latitudes. Comparando as taxas de produção estimadas a partir das equações empíricas com as obtidas experimentalmente, observa-se diferenças expressivas nas estimativas de produção secundária, o que sugere a influência de outras variáveis além daquelas consideradas pelos modelos. / The present study evaluates how the pelagic copepod community structure and production from the inner shelf off Ubatuba (SP, Brazil) responded to environmental variability from July 2005 to June 2008. During these three years copepod secondary production was studied by the application of growth empirical models and weight-specific growth estimates obtained through egg production experiments. Reproductive aspects of 17 copepod species (10 calanoid, 3 cyclopoid and 4 harpacticoid) were analyzed through incubation experiments and indirect methods to obtain production and egg hatching success rates. Copepod community was represented by 70 species and was characterized by high values of richness, diversity and evenness. Copepods had great variability in mean abundance values (4,726 ± 3,711 ind. m-3) and biomass (7.42 ± 5.64 mg C m-3) and were dominated by small size species (< 1,000 µm), especially Oncaea waldemari adult females and immature copepodites of paracalanids and clausocalanids. When compared to other tropical and subtropical environments, the copepod community in the study area had high average abundance and biomass. Mean secondary production rates had high temporal variability (1.13 ± 1.11 mg C m-3 day-1), with an important contribution from immature copepodites of broadcast spawner species. Production values were also high but mean Production/Biomass ratios were similar when compared to other tropical and subtropical environments. The periodic SACW (South Atlantic Central Water) intrusions seem to be the main responsible for the variability in community structure and production. Most months non-influenced by SACW had abundance, biomass and production values lower than the annual average. However, copepod community fluctuations may not have responded only to SACW intrusions, but also to inter- and intra-specific relations. Broadcast spawner species had mean egg production rates similar to the ones obtained in other tropical and subtropical regions, while sac spawners showed slightly lower values. Nevertheless, occasional production peaks were recorded for the latter, suggesting that these copepods have reproductive strategies to compensate for low productivity periods. Some species reproduction traits seem to be related to intra-specific factors, such as egg size and the male/female ratio. Besides, broadcast spawners were probably influenced by temperature and food. The relationship between female and egg size and weight from 32 pelagic copepod species showed that inter-specific variability observed in these proportions was similar to those observed for high-latitude species. When reproduction rates estimated from empirical equations with those obtained experimentally are compared, expressive differences in secondary production estimates emerge, which suggests the influence of other variables in addition to those accounted for by empirical models.

O presente estudo avalia como a estrutura e a produção da comunidade de copépodes pelágicos da plataforma interna ao largo de Ubatuba (SP, Brasil) responderam às variações ambientais durante o período de julho de 2005 a junho de 2008. Durante estes três anos, a produção secundária dos copépodes foi estudada por meio da aplicação de modelos empíricos de crescimento e de estimativas de crescimento peso-específico obtidas através de experimentos de produção de ovos. Aspectos reprodutivos de 16 espécies de copépodes (9 calanóides, 3 ciclopóides e 4 harpacticóides) foram analisados neste período, através de experimentos de incubação e de métodos indiretos de obtenção de taxas de produção e viabilidade dos ovos. A comunidade de copépodes esteve representada por 70 espécies e foi caracterizada por altos valores de riqueza, diversidade e eqüitabilidade. Os copépodes apresentaram grande variabilidade nos valores médios de densidade (4726 ± 3711 ind. m-3) e de biomassa (7,42 ± 5,64 mg C m-3) e foram dominados por espécies de pequeno porte (< 1000 µm), destacando-se as fêmeas adultas de Oncaea waldemari e os copepoditos imaturos de paracalanídeos e clausocalanídeos. Quando comparada com outros ambientes tropicais e subtropicais, a região estudada apresentou valores elevados de densidade e biomassa. Da mesma maneira, a produção secundária média apresentou variabilidade temporal elevada (1,13 ± 1,11 mg C m-3 dia-1), com uma importante contribuição dos copepoditos imaturos de espécies dispersoras de ovos. No geral, os valores médios registrados foram considerados altos quando comparado com outros ambientes tropicais e subtropicais, embora a razão Produção/Biomassa média tenha sido similar às registradas nestes locais. A intrusão periódica da ACAS parece ter sido a principal responsável pelas alterações observadas na estrutura e produção da comunidade. A maioria dos meses não influenciados pela ACAS apresentou valores de densidade, biomassa e produção inferiores às respectivas médias. Entretanto, os resultados observados sugerem que as flutuações da comunidade de copépodes podem responder não apenas à intrusão da ACAS, mas também a uma complexa conjunção de fatores, incluindo as próprias relações inter e intra-específicas. Com relação à reprodução, as espécies dispersoras de ovos apresentaram taxas médias de produção de ovos similares às obtidas em outras regiões tropicais e subtropicais, enquanto que as retentoras apresentaram valores levemente inferiores. Entretanto, foram registrados picos ocasionais de produção destas últimas espécies, sugerindo que estes copépodes possuem estratégias que compensam os meses de baixa produtividade. A reprodução de algumas espécies analisadas parece ser associada a fatores intra-específicos, tais como o tamanho dos ovos e a razão entre machos e fêmeas. Além disso, as espécies dispersoras analisadas são provavelmente influenciadas pela temperatura e pelo alimento. A relação entre os tamanhos e pesos de fêmeas e ovos de 32 espécies de copépodes pelágicos mostrou que a variabilidade interespecífica observada nessas proporções é similar à tendência observada para espécies de altas latitudes. Comparando as taxas de produção estimadas a partir das equações empíricas com as obtidas experimentalmente, observa-se diferenças expressivas nas estimativas de produção secundária, o que sugere a influência de outras variáveis além daquelas consideradas pelos modelos. / The present study evaluates how the pelagic copepod community structure and production from the inner shelf off Ubatuba (SP, Brazil) responded to environmental variability from July 2005 to June 2008. During these three years copepod secondary production was studied by the application of growth empirical models and weight-specific growth estimates obtained through egg production experiments. Reproductive aspects of 17 copepod species (10 calanoid, 3 cyclopoid and 4 harpacticoid) were analyzed through incubation experiments and indirect methods to obtain production and egg hatching success rates. Copepod community was represented by 70 species and was characterized by high values of richness, diversity and evenness. Copepods had great variability in mean abundance values (4,726 ± 3,711 ind. m-3) and biomass (7.42 ± 5.64 mg C m-3) and were dominated by small size species (< 1,000 µm), especially Oncaea waldemari adult females and immature copepodites of paracalanids and clausocalanids. When compared to other tropical and subtropical environments, the copepod community in the study area had high average abundance and biomass. Mean secondary production rates had high temporal variability (1.13 ± 1.11 mg C m-3 day-1), with an important contribution from immature copepodites of broadcast spawner species. Production values were also high but mean Production/Biomass ratios were similar when compared to other tropical and subtropical environments. The periodic SACW (South Atlantic Central Water) intrusions seem to be the main responsible for the variability in community structure and production. Most months non-influenced by SACW had abundance, biomass and production values lower than the annual average. However, copepod community fluctuations may not have responded only to SACW intrusions, but also to inter- and intra-specific relations. Broadcast spawner species had mean egg production rates similar to the ones obtained in other tropical and subtropical regions, while sac spawners showed slightly lower values. Nevertheless, occasional production peaks were recorded for the latter, suggesting that these copepods have reproductive strategies to compensate for low productivity periods. Some species reproduction traits seem to be related to intra-specific factors, such as egg size and the male/female ratio. Besides, broadcast spawners were probably influenced by temperature and food. The relationship between female and egg size and weight from 32 pelagic copepod species showed that inter-specific variability observed in these proportions was similar to those observed for high-latitude species. When reproduction rates estimated from empirical equations with those obtained experimentally are compared, expressive differences in secondary production estimates emerge, which suggests the influence of other variables in addition to those accounted for by empirical models.