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

Monitoring elasmobranch assemblages in a data-poor country from the Eastern Tropical Pacific using baited remote underwater video stations

“…Differences among MPAs may be related to size, human accessibility and levels of enforcement, which have been previously identified as key drivers of MPA efficiency towards elasmobranch protection 55 – 57 . Cocos Island, for example, is a relatively pristine, remote and diverse island that currently has one of the largest fish biomass in the Eastern Tropical Pacific 58 , 59 . Moreover, given its status as a UNESCO World Heritage Site, more resources for surveillance and enforcement are allocated to Cocos Island than any other MPA in Costa Rica.…”

“…Given the high level of endemism and biodiversity, Cocos Island was declared a National Park in 1978 and an UNESCO World Heritage site in 1997. The MPA has a surface area of approximately 2011 km 2 60 , and has one of the largest fish biomasses in the tropics 58 , 59 , 93 . Cocos Island has a complex bottom morphology 94 , with a high variety of habitats including, sandy and rocky bottoms at various depths and extensive coral reefs mainly found at the north side of the island inside two of the largest bays along the coast 86 , 95 .…”

First record of a potential neonate tiger shark (Galeocerdo cuvier) at a remote oceanic island in the Eastern Tropical Pacific

“…The tiger shark, Galeocerdo cuvier (Péron & Lesueur 1822), is a large, iconic predator with a circumglobal distribution in warm‐temperate and tropical marine waters (Compagno, 1984). Despite its wide distribution and apex predator role in some tropical reef ecosystems (Ferreira et al ., 2017; Fourriére et al ., 2019; Heithaus et al ., 2014; Hilting et al ., 2013), the identification of mating, pupping and nursery areas for G. cuvier is still lacking (Holland et al ., 2019). Contrary to many other carcharhinids, G. cuvier has not been generally observed using specific locations as nursery areas (Driggers et al ., 2008; Holland et al ., 2019; Holmes, 2015; Whitney & Crow, 2007).…”

“…Because water turbidity offers some degree of protection from visual predators in shark nurseries (Heupel et al ., 2019; Yates et al ., 2015), the presence of turbid waters at Yglesias Bay could explain why a neonate of G. cuvier was found at this less complex habitat. Another hypothesis is that large litter sizes and a fast growth of YOY of this species (Branstetter, 1987) in an environment with abundant prey resources such as Cocos Island (Edgar et al ., 2011; Fourriére et al ., 2019; Friedlander et al ., 2012) may compensate the need for protection from sheltered areas (Driggers et al ., 2008). Finally, there is also the possibility that this neonate dispersed from its original parturition site at or near Cocos Island and moved to Yglesias Bay afterwards where it was detected by our BRUVS.…”

Avistamientos de <i>Orcinus orca</i> (Linnaeus, 1758) (Cetartiodactyla: Odontoceti: Delphinidae) en el Pacífico costarricense (1990-2020)

“…El estudio de los cetáceos marinos ha sido una actividad de gran importancia para las sociedades humanas debido a que permite comprender dinámicas ecosistémicas (Parsons et al 2015). Se han efectuado varias investigaciones referentes a características ecológicas de los cetáceos residentes y visitantes en las aguas de nuestro país (Steiger et al 1991;Wade & Gerrodette, 1993;Acevedo & Smultea, 1995;Acevedo & Burkhart, 1998;May-Collado & Morales-Ramírez, 2005;Rasmussen et al 2007;Palacios-Alfaro, 2009;Rasmussen et al 2012;Martínez-Fernández et al 2011;May-Collado & Forcada, 2012;Martínez-Fernández et al 2014;Acevedo et al 2017), y la información devengada no solo ha permitido tener una mejor idea de la diversidad del grupo en el país, adicionalmente nos provee herramientas para comprender, de mejor manera, los ensamblajes tróficos existentes en nuestro territorio marítimo (May-Collado et al 2018;Fourriére et al 2019). Esto facilitó el desarrollo de una importante industria de observación de cetáceos, de forma predominante en el Pacífico Sur del país, y enriquecer el conocimiento sobre las orcas en el país, posiblemente, permitiría aumentar el interés del público general, y, por consiguiente, atraer un mayor número de personas que deseen ver estos animales (Rodríguez-Fonseca & Fischel-Quirós, 2007;Hoyt & Iñíguez, 2008;Montero-Cordero & Lobo, 2010).…”