Tartarugas marinhas da Bacia Potiguar/RN: diagnóstico, biologia alimentar e ameaças

This work aimed to study the diversity and distribution of marine sea turtles stranded in Potiguar Basin, Rio Grande do Norte, as well as aspects related to feeding behavior associated with human impacts. The study was conducted through the analysis of data from stranded animals, recorded in a daily monitoring in an area bounded on the north by the municipality of Aquiraz, in the state of Ceará, and the east by the municipality of Caicara do Norte, in the state of Rio Grande do Norte. Stranded dead animals were necropsied and for the analysis of the diet of animals, esophagus, stomach and intestines were fixed in 10% formalin and after that, the stomach contents were sorted and stored in 70% alcohol. Representative fragments of these organs were removed for making histological slides, with a view to histological characterization of the digestive tract. 2.046 occurrences of turtles were recorded during the period from 01/01/2010 to 31/12/2012. The Chelonia mydas species showed the highest number of records and it was observed in 66.81 % (N = 1,367) of cases; followed by Eretmochelys imbricata with 4.45 % (N = 91) and by Lepidochelys olivacea with 1.22% (N = 25). The Caretta caretta and Dermochelys coriacea species were, respectively, 0.93 % (N = 19) and 0.05 % (N = 1) records of strandings. In 26.54 % of cases, it was not possible to identify the species. Regarding the spatial distribution, the stretch A was the one that had the highest number of strandings and a larger number of records were registered in the warm months of the year. The dietary analysis showed that C. mydas fed preferentially on algae; C. caretta had a diet with a predominance of the item "coral´s fragments" and E. imbricata species showed preference for an animal origin material. Related to this anthropic interaction, 57.14 % (n = 76) of animals that died at the rehabilitation s base, showed cause of death due to complications from ingesting debris. According to the data presented, the Potiguar Basin presents itself as an area with important diversity and distribution of marine sea turtle as well is characterized as a feeding and nidification area for these species

Occurrence of Amphiorchis solus (Simha & Chattopadhyaya, 1970) (Digenea: Spirorchiidae) Infecting the Green Turtle Chelonia mydas Linnaeus, 1758 (Testudines: Cheloniidae) in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Helmintofauna de Chelonia mydas necropsiadas na base do Projeto Tamar-Ibama em Ubatuba, Estado de São Paulo, Brasil

Pós-graduação em Biologia Geral e Aplicada - IBB

Estudo da helmintofauna de tartarugas marinhas procedentes da costa brasileira

Pós-graduação em Biologia Geral e Aplicada - IBB

Ecosistemas errantes: Epibiontes como indicadores biogeográficos de tortugas marinas de Canarias

Programa de doctorado: Ecología y gestión de recursos vivos marinos

Letter from the Editor Spring/Summer 2010

Despite the horrific oil spill in the Gulf and possible extinction of Kemp's Ridley sea turtles, there are still reasons to celebrate the shore--for example, Connecticut's shorebirds.

What was natural in the coastal oceans?

Humans transformed Western Atlantic coastal marine ecosystems before modern ecological investigations began. Paleoecological, archeological, and historical reconstructions demonstrate incredible losses of large vertebrates and oysters from the entire Atlantic coast. Untold millions of large fishes, sharks, sea turtles, and manatees were removed from the Caribbean in the 17th to 19th centuries. Recent collapses of reef corals and seagrasses are due ultimately to losses of these large consumers as much as to more recent changes in climate, eutrophication, or outbreaks of disease. Overfishing in the 19th century reduced vast beds of oysters in Chesapeake Bay and other estuaries to a few percent of pristine abundances and promoted eutrophication. Mechanized harvesting of bottom fishes like cod set off a series of trophic cascades that eliminated kelp forests and then brought them back again as fishers fished their way down food webs to small invertebrates. Lastly, but most pervasively, mechanized harvesting of the entire continental shelf decimated large, long-lived fishes and destroyed three-dimensional habitats built up by sessile corals, bryozoans, and sponges. The universal pattern of losses demonstrates that no coastal ecosystem is pristine and few wild fisheries are sustainable along the entire Western Atlantic coast. Reconstructions of ecosystems lost only a century or two ago demonstrate attainable goals of establishing large and effective marine reserves if society is willing to pay the costs. Historical reconstructions provide a new scientific framework for manipulative experiments at the ecosystem scale to explore the feasibility and benefits of protection of our living coastal resources.

The vertebrate fauna of the Selma Formation of Alabama. Rainer Zangerl.

v.3:no.5(1960)

Green turtle somatic growth dynamics in a spatially disjunct Great Barrier Reef metapopulation

The growth dynamics of green sea turtles resident in four separate foraging grounds of the southern Great Barrier Reef genetic stock were assessed using a nonparametric regression modeling approach. Juveniles recruit to these grounds at the same size, but grow at foraging-ground-dependent rates that result in significant differences in expected size- or age-at-maturity. Mean age-at-maturity was estimated to vary from 25-50 years depending on the ground. This stock comprises mainly the same mtDNA haplotype, so geographic variability might be due to local environmental conditions rather than genetic factors, although the variability was not a function of latitudinal variation in environmental conditions or whether the food stock was seagrass or algae. Temporal variability in growth rates was evident in response to local environmental stochasticity, so geographic variability might be due to local food stock dynamics. Despite such variability, the expected size-specific growth rate function at all grounds displayed a similar nonmonotonic growth pattern with a juvenile growth spurt at 60-70 cm curved carapace length, (CCL) or 15-20 years of age. Sex-specific growth differences were also evident with females tending to grow faster than similar-sized males after the Juvenile growth spurt. It is clear that slow sex-specific growth displaying both spatial and temporal variability and a juvenile growth spurt are distinct growth behaviors of green turtles from this stock.

A bloom of Lyngbya majuscula in Shoalwater Bay, Queensland, Australia: An important feeding ground for the green turtle (Chelonia mydas)

Lyngbya majuscula, a toxic cyanobacterium, was observed blooming during June-July (winter) 2002 in Shoalwater Bay, Queensland, Australia, an important feeding area for a large population of green turtles (Chelonia mydas). The bloom was mapped and extensive mats of L majuscula were observed overgrowing seagrass beds along at least 18 km of coast, and covering a surface area of more than I I km(2). Higher than average rainfall preceded the bloom and high water temperatures in the preceding summer may have contributed to the bloom. In bloom samples, lyngbyatoxin A (LA) was found to be present in low concentration (26 mu g kg(-1) (dry weight)), but debromoaplysiatoxin (DAT) was not detected. The diet of 46 green turtles was assessed during the bloom and L. majuscula was found in 51% of the samples, however, overall it contributed only 2% of the animals' diets. L. majuscula contribution to turtle diet was found to increase as the availability of the cyanobacterium increased. The bloom appeared to have no immediate impact on turtle body condition, however, the presence of a greater proportion of damaged seagrass leaves in diet in conjunction with decreases in plasma concentrations of sodium and glucose could suggest that the turtles may have been exposed to a Substandard diet as a result of the bloom. This is the first confirmed report of L. majuscula blooming in winter in Shoalwater Bay, Queensland, Australia and demonstrates that turtles consume the toxic cyanobacterium in the wild, and that they are potentially exposed to tumour promoting compounds produced by this organism. (c) 2005 Elsevier B.V. All rights reserved.

Patterns and ecosystem consequences of shark declines in the ocean

Whereas many land predators disappeared before their ecological roles were studied, the decline of marine apex predators is still unfolding. Large sharks in particular have experienced rapid declines over the last decades. In this study, we review the documented changes in exploited elasmobranch communities in coastal, demersal, and pelagic habitats, and synthesize the effects of sharks on their prey and wider communities. We show that the high natural diversity and abundance of sharks is vulnerable to even light fishing pressure. The decline of large predatory sharks reduces natural mortality in a range of prey, contributing to changes in abundance, distribution, and behaviour of small elasmobranchs, marine mammals, and sea turtles that have few other predators. Through direct predation and behavioural modifications, top-down effects of sharks have led to cascading changes in some coastal ecosystems. In demersal and pelagic communities, there is increasing evidence of mesopredator release, but cascading effects are more hypothetical. Here, fishing pressure on mesopredators may mask or even reverse some ecosystem effects. In conclusion, large sharks can exert strong top-down forces with the potential to shape marine communities over large spatial and temporal scales. Yet more empirical evidence is needed to test the generality of these effects throughout the ocean.

Temporary sequences and description of the emergency of newborns loggerhead in the Cape Verde archipelago

[EN] Sea turtles bury their eggs in the sand of the beach, where they incuba te. After a period of approximately two months, hatchlings break the eggshell and remain inside the chamber for three to seven days (Hays & Speakman, 1993). Then they leave the nest and emerge to the surface of the beach, going quickly towards the surf, to begin their pelagic and developmental stage (e.g., López-Jurado & Andreu, 1998). Hatchlings usually do not emerge from the nest as a single group. They emerge in groups at different moments, resulting in more than one emergence per nest during sorne days (Whitherington et al.,4 1990; Hays et al., 1992; Peters et al., 1994).

Preliminary approach to the hatchlings sex-ratio of a population of Caretta caretta of Boavista island, Cape Verde Archipielago (Western Africa).

[EN] A nesting population of loggerhead sea turtles Caretta caretta has recently been described for Boa Vista Island, Cape Verde Archipelago (Western Africa). Since 1998, “Projecto Cabo Verde Natura 2000” has monitored three beaches during the turtle breeding season. The beaches being monitored - Calheta, Errata and Ponta Cosme - are located in the southeast part of Boa Vista Island. This work intends to give a first insight into the Boa Vista Island sea turtle population’s sex ratio using a histological approach, as sexual determination in sea turtles is known to be temperature-dependent (TSD or temperature-dependent sex determination).

Climate change and the evolution of loggerhead sex-ratio in Cabo Verde

[EN] Global warming can affect nesting success of sea turtles due to the rise of the sea level and the subsequent increased inundation or erosion of nesting beaches. Moreover, it can reduce male production to levels that can alter reproduction due to their temperature dependant sex determination (TSD). Now, mean nest temperatures all around the world predict a predominance of female hatchlings, and this trend may increase with global warming in the next decades.