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For the Western Indian Ocean region, there is a significant knowledge gap regarding marine turtle nesting on the continental coast of East Africa. Here we present results from a long-term (2000–2020) community-based monitoring programme in and around Watamu Marine National Park, Kenya, covering 30 km of coastline (c. 6% of the national total). Conservation actions effectively protected nesting turtles and resulted in a near-total cessation of illegal egg harvesting in Watamu Marine National Park. Collected data indicate this is an important marine turtle nesting index site in Kenya and the wider region. Green turtle Chelonia mydas nests were most common (95%), followed by olive ridley turtles Lepidochelys olivacea (4%), with occasional nests of hawksbill Eretmochelys imbricata and leatherback turtles Dermochelys coriacea. Clutches per season increased significantly over the 20-year monitoring period for green turtles (50%) and showed a positive trend for olive ridley turtles. Watamu remains an area at risk from human pressures such as coastal development. Clutch distribution along the Watamu Marine National Park beach has shifted over time, probably because of coastal development and disturbance. Illegal take of adults and eggs continues in areas north and south of the Watamu Marine National Park, possibly slowing rates of recovery. Clutches deemed at risk were moved to a safe location within the National Park, and hatching success was high. Continued conservation efforts, including wider engagement with stakeholders to reduce human pressures, are needed to ensure the perpetuation of this nesting site. [ABSTRACT FROM AUTHOR]

The leatherback turtle Dermochelys coriacea, the only extant species in its family, is categorized as Vulnerable on the IUCN Red List. The protection of nesting beaches and the associated conservation efforts along the Western Atlantic coast of Central America have improved the population trends of some of the most important rookeries. Here we report the life history, ecology and population trends of leatherback turtles over 18 years (1994–2012, excluding 1998) of effective protection in the Pacuare Nature Reserve, on the Caribbean coast of Costa Rica. A mean density of 142 nests per km, probably the highest in Central America, indicates the importance of this rookery within the Caribbean region. Long-term conservation efforts at the Reserve have significantly reduced poaching and contributed to maintaining a high level of hatchling production. Long-term monitoring has also facilitated estimation of relevant demographic parameters of the population, such as nesting success (mean 69.8 ± SD 7.3%), clutch size (which is positively correlated with female size), hatching success (mean 55.2 ± SD 6.0%), remigration interval (2.5 years), and growth rate of remigrant females (mean 0.3 ± SD 1.0 cm per year), which is slightly faster than growth rates reported for Pacific leatherback turtles. Overall, efforts at Pacuare have been successful in protecting leatherback turtles and understanding their life history, highlighting the importance of long-term conservation projects for maintaining threatened leatherback populations. [ABSTRACT FROM AUTHOR]

The beaches of Jaragua National Park in the Dominican Republic are the country's last known major nesting site for the leatherback marine turtle Dermochelys coriacea. This nesting aggregation is threatened by widespread illegal egg take, and clutch relocation and artificial incubation have been carried out as protection measures since 1974. We assess the efficacy of such efforts and investigate how artificial incubation may be influencing the success and sex ratios of clutches. We compare hatching success, incubation duration and embryo mortality in in-situ clutches (n = 43) with those incubated artificially at sites in the east and west of the Park (n = 35 and n = 31, respectively). Our results show that in the west, artificial incubation significantly decreases hatching success in clutches. In the east the duration of incubation is increased, which we predict would result in an increase in the number of males from these clutches. Clutch relocation is currently the only viable conservation option for clutches on eastern beaches because of illegal egg take but action is needed to ensure that the natural sex ratio is not distorted. However, on the western beaches in situ clutch incubation seems possible through beach protection. Further community engagement and enforcement are required to improve conservation measures at eastern beaches if long-term, less sustainable intervention is to be avoided. [ABSTRACT FROM AUTHOR]

The article offers news briefs related to natural conservation. A study has identified areas that are particularly significant for migration patterns of leatherback turtles in the Pacific Ocean. A research of the effectiveness of protected areas in mitigating extinction risks has revealed that species in site with greater protected area coverage have had smaller growth in extinction risk than species in unprotected area. A report published by the Royal Society highlighted global challenges.

Predation can be an important driver of population dynamics but can also pose a dilemma to conservation managers if the species interacting are of conservation concern or have a high public profile. For 5 years we conducted regular transect surveys to monitor the spatial and temporal patterns of predation of adult marine turtles by jaguars Panthera onca in Tortuguero National Park, Costa Rica. Predation occurs throughout the study site on Tortuguero Beach although at lower rates at the northern and southern ends, probably because of increased human presence in these areas. There was a marked increase in predation, from an average of < 2 turtles predated per survey in the first season to > 5 predated per survey in the last, with 676 jaguar-predated marine turtles recorded during the study period. With a minimum of 189 individuals predated in the last season, predation of adult turtles has now reached a magnitude never before recorded in a marine turtle rookery. Although the nesting population of marine turtles in Tortuguero is one of the largest in the world and suffers from both direct and indirect anthropogenic pressures, the increase in predation by jaguars makes this ecological interaction relevant to the management of both the jaguar and marine turtle populations. The situation could lead to a potential conflict in conservation strategies that, given the flagship role of the species involved, will need to be addressed both in the context of species management and conservation marketing. [ABSTRACT FROM AUTHOR]

We examined impacts from effective predator management on nesting success of marine turtles in an exceptional nesting year at Hobe Sound National Wildlife Refuge, Florida, USA, a beach with a high density of nesting marine turtles that has a history of severe nest predation. Historically up to 95% of nests were predated, primarily by raccoons Procyon lotor and, more recently, armadillos Dasypus novemcinctus. Predator control was identified as the most important conservation tool for marine turtle reproduction. Predator management by refuge staff as ancillary duties typically only held predation levels to c. 50%. However, when experts in predator control were employed predation was substantially reduced. An extraordinary opportunity to evaluate the biological and economic benefits of this management approach occurred in 2008, a year with exceptionally heavy nesting. Loggerhead turtle Caretta caretta nesting resurged, green Chelonia mydas and leatherback Dermochelys coriacea turtles nested in record numbers, producing twice or more than their median number of nests, and the first Kemp’s ridley Lepidochelys kempii nest was observed. Overall predation was 14.7%, resulting in an estimated > 128,000 additional hatchlings emerging compared to estimates had no predator management been in place and historical predation rates occurred, and > 56,000 hatchlings more than expected had predator management been conducted as ancillary duties rather than by experts. The USD 12,000 investment for expert predator management equated to only USD 0.09 spent for each additional hatchling produced compared to the scenario of no predator control and only USD 0.21 compared to the scenario of predator control as ancillary duties. [ABSTRACT FROM PUBLISHER]

The article offers information on several studies related to biodiversity and ecosystem. It mentions a study from a 2011 issue of "ScienceDaily" which deals with the migratory routes of leatherback turtles through satellite tracking. It features a study from a 2010 issue of "Nature" which relates biodiversity with disease transmission. The article also features the new plant species discovered by Royal Botanic Gardens, Kew (Kew Garden) botanists including Mozambican mistletoe and parsley ferns.

Six marine turtle species are reported from the coastal waters of the Republic of the Congo. Among them, nesting by the Critically Endangered leatherback Dermochelys coriacea and Endangered olive ridley Lepidochelys olivacea marine turtles occurs annually from September to April on Congolese beaches. We developed a methodology to model the nesting season of marine turtles and apply it to the time series of nest counts for six nesting beaches monitored over 2-4 years. There is a peak of nesting activity in early January for leatherback turtles and early December for olive ridley turtles. We show a decline of olive ridley nests during this period whereas leatherback nesting increased, and propose that differential threats for these two species explain such a contrasted pattern. [ABSTRACT FROM AUTHOR]

The globally distributed leatherback turtle Dermochelys coriacea is subject to fisheries bycatch throughout its range. Protection from fisheries within pelagic foraging habitats is difficult to achieve but may be more tractable when populations are concentrated near neritic breeding and nesting grounds. We used satellite telemetry to describe patterns of habitat utilization during the internesting period for seven leatherback turtles nesting at Mayumba National Park in Gabon on the equatorial West African coast. The National Park includes critical nesting grounds and a marine protected area to 15 km offshore. Turtles dispersed widely from the nesting beach spending a mean of 62 ± SD 26% of tracking time outside the confines of the National Park. This propensity to disperse is likely to increase the chance of deleterious interactions with fisheries in the region. Patterns of habitat utilization indicate the need for wider spatial scale planning on the West African continental shelf to enhance protection of leatherback turtles when they are seasonally occupying these habitats in great numbers for breeding and nesting. [ABSTRACT FROM AUTHOR]

Industrial logging is expanding rapidly in Central African rainforests. We suggest that logging operations in this region pose an indirect threat to nesting marine turtles, especially the Critically Endangered leatherback turtle Dermochelys coriacea. This occurs because some logs are being lost or abandoned during downriver transport to coastal timber yards; the lost logs float out to sea and then often wash ashore, where they accumulate on beaches used by nesting turtles. We used a light aircraft to survey logs along the entire coastline of Gabon, and also studied the impacts of logs at Pongara Beach, one of the world's most important turtle nesting areas, during the 2002-2003 and 2003-2004 breeding seasons. Nearly 11,000 lost logs were counted along Gabon's beaches, with an estimated commercial value of USD 11.1 million. Logs were unevenly distributed along the coast, reaching a peak density of 247 logs km-1. At Pongara, logs blocked 30.5% of the beach. These logs had a number of negative effects on marine turtles, causing 8-14% of all nesting attempts (n = 2,163) to be aborted or disrupted. Initiatives to remove lost logs and driftwood from critical nesting beaches may be the most effective means to reduce their deleterious impacts on threatened marine turtles. [ABSTRACT FROM AUTHOR]

The status of marine turtles in Angola, West Africa, is poorly known, and therefore during 2000-2006 a combination of both dedicated and opportunistic beach and at-sea turtle surveys were carried out, and interviews conducted with fishing communities and at markets. Green Chelonia mydas, olive ridley Lepidochelys olivacea, leatherback Dermochelys coriacea and loggerhead turtles Caretta caretta were recorded, and nesting of the first three species confirmed during September-March (peaking November-December). Green turtles nested mainly in the south, leatherback turtles in north and central Angola, and olive ridley turtle nesting was widespread. Olive ridley turtle nest density at Palmeirinhas averaged 32 nests km-1. At-sea surveys produced 298 turtle records, with peak occurrence during August. Significant anthropogenic-related mortality (including exploitation of meat and eggs and fishing bycatch) was recorded, in addition to natural predation and other threats. Maintenance of the long- term sustainability of these turtle populations should focus on the involvement of fishing communities and increasing awareness throughout Angola. [ABSTRACT FROM AUTHOR]