First record of an adult Galapagos slipper lobster, Scyllarides astori, (Decapoda, Scyllaridae) from Isla del Coco, Eastern Tropical Pacific

The Galapagos Slipper lobster, Scyllarides astori, has been reported from rocky reefs along the Eastern Tropical Pacific: the Gulf of California, the Galapagos Archipelago and mainland Ecuador. Although larval stage S. astori has been found in other localities throughout this range, there are no records of adults inhabiting waters between these three locations. Here we present the first record of an adult S. astori from Isla del Coco and Costa Rican Pacific waters. The single specimen, a male, was hand-collected within a coral reef in Pájara islet. This finding increases the reported lobster species richness of Costa Rican Pacific waters to six species and expands the adult geographic range of S. astori to Isla del Coco

Species richness and density of seabirds in Isla del Coco bays, Costa Rica, related to the occurrence of breeding colonies

Isla del Coco is one of the five oceanic islands situated on the eastern tropical Pacific Ocean and represents an important nesting and roosting site for seabirds. Despite several factors that can potentially impact its seabird fauna, knowledge about species density and distribution as well as of the size of its breeding colony is limited, currently consisting of bird checklists only. The objective of this study is to compare seabird species richness and density at four bays at Isla del Coco as a function of proximity to breeding colonies. In terms of richness, no pattern was identified. However, we found that the two sites situated near main breeding colonies had higher seabird densities (> 5 individuals ha-1) than the two sites without major breeding colonies. The difference in the densities could be explained by food availability and the presence of nesting habitat. It is possible that the seabirds are foraging near the colonies rather than venturing into long offshore trips.UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologíaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR

Energy flow structure and role of keystone groups in shallow water environments in Isla del Coco, Costa Rica, Eastern Tropical Pacific

Isla del Coco (Costa Rica) forms part of the five oceanic islands of the Eastern Tropical Pacific and is well known for its high biodiversity and great endemism. While several marine biological and oceanographical surveys have been conducted around the island over the past 35 years, an integrated, systematic view of the shallow water system is lacking as is an assessment of the impact of illegal fisheries. The aim of the study was thus to identify the main biological compartments of the Isla del Coco system and to quantify its energy flow structure through the development of a trophic model for the shallow water environments (≤30 m). With the software Ecopath with Ecosim, and based on the model structure previously used for Darwin and Wolf islets in the Galápagos Archipelago, a trophic model was developed using information from several field surveys and additional data from similar systems. The total biomass of the Isla del Coco system (1,972.25 t km−2) was mainly comprised of high trophic level species such as hammerhead shark, pelagic predatory fish and other sharks. The reef ecosystem is in a healthy (relatively undisturbed) state and dominated by large apex predators and mesopredators. Of the keystone groups identified (toothed cetaceans, tiger sharks, other sharks, benthic omnivorous fish and pelagic predatory fish), toothed cetaceans and tiger sharks were identified as having the strongest influence on the structure and diversity of the community through direct and indirect interactions. The Isla del Coco ecosystem presents a higher biomass than a similar system in the Galápagos archipelago, likely due to lower fishing pressure and higher system maturity.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Benefits of protection on reef fish assemblages in a human impacted region in Costa Rica

In recent years, there has been a health decrease in marine ecosystems. Due to this accelerated degradation, there is a more pressing need to investigate the effectiveness of MPAs in these degraded zones. In this work, we evaluate the effect of MPAs over species richness, biomass and size of reef fishes. The sampling was conducted in 31 sites in the north Pacific coast of Costa Rica in 2013 and 2014. We found a positive effect of MPAs on biomass and community structure, as almost all commercially important species were more abundant in MPAs. Apex predators, carnivores and herbivores showed higher biomasses in protected areas, while planktivorous were similar among sites. As well, target species of artisanal fisheries and dive-ornamental fisheries were larger in MPAs. Areas closed to fishing can contribute to keeping biomass high, improve species richness in the region, and help to recover ecosystem services in coral reefs, even in anthropogenic impacted areas. The improving of regulations in and out of MPAs will assure the ecosystem services and life quality of coastal populations.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Updated checklist and analysis of completeness of the marine fish fauna of Isla del Coco, Pacific of Costa Rica

Isla del Coco, Costa Rica, is one of the five groups of oceanic islands of the Eastern Tropical Pacific (ETP), and is considered one of the most diverse. Since the mid-19th century, it has been the target of a number of scientific research expeditions that have produced specimen collections which are housed in natural history museums around the world. The fish assemblage of Isla del Coco is considered one of the most speciose and best documented group of marine organisms of the island. Despite this, recent work has resulted in a need to update the checklist for this important group. We performed a completeness analysis of the ichthyofauna of Isla del Coco based on scientific publications and reports of expeditions, specimens in foreign and national collections, and field surveys. We confirmed the presence of 514 species of marine fishes, representing an increase of approximately 23 % compared to what was previously reported. From a habitat perspective, 58 % of this assemblage is typically reef fishes, while the remaining 42 % are deep-water, and pelagic species. The average expected reef fish species richness is 318.2 ± 7.3, suggesting that the local inventory represents 93.7 % of the expected total richness. Our updated list and greater number of species has particular relevance to the conservation efforts at Isla del Coco, since current conservation efforts are protecting at least 50 % of ETP fish species and about 40 % of Costa Rica’s Pacific fish species.Fonds Français pour l’Environnement Mondial/[]/FFEM/FranciaConsejo Nacional de Rectores de las Universidades Públicas de Costa Rica/[]/CONARE/Costa RicaUniversidad de Costa/[]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Ciencias del Mar y Limnología (CIMAR)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de BiologíaUCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de Zootecni