Beach almond (Terminalia catappa, Combretaceae) seed production and predation by scarlet macaws (Ara macao) and variegated squirrels (Sciurus variegatoides) / Producción de semillas y depredación del almendro de playa (Terminalia catappa, Combretaceae) por lapas rojas (Ara macao) y ardillas chizas (Sciurus variegatoides)

Knowledge of ecological impacts of exotic beach almond (Terminalia catappa) in the central Pacific of Costa Rica are little known, but studies have found this species to be a potentially important food source for endangered scarlet macaws (Ara macao). In this study, reproductive phenology and seed predation by variegated squirrels (Sciurus variegatoides) and scarlet macaws were measured during March and April 2011 on beaches of central Pacific coastal Costa Rica. Seed productivity and predation levels were quantified on a weekly basis for 111 beach almond trees to assess the importance of beach almond as a food source for scarlet macaws and the extent of resource partitioning between seed predators. Seed production of the trees was great (about 194 272 seeds) and approximately 67% of seeds were predated by seed predators. Macaws consumed an estimated 49% of seeds while squirrels consumed 18%. Additionally, evidence of resource partitioning between squirrels and macaws was found. Scarlet macaws preferred to feed on the northern side and edge of the canopy while squirrels preferred to feed on the southern and inside parts of the canopy. Both species ate most seeds on the ocean side of the tree. Despite the status of this tree as an exotic species, the beach almond appears to be an important resource for scarlet macaw population recovery. The resource produced by this tree should be taken into account as reforestation efforts continue in Costa Rica. Rev. Biol. Trop. 62 (3): 929-938. Epub 2014 September 01.

El conocimiento de los impactos ecológicos del almendro de playa exótico (Terminalia catappa) en el Pacífico Central de Costa Rica son poco conocidos, pero los estudios han encontrado que esta especie es una fuente de alimento potencialmente importante para la lapa roja (Ara macao), en peligro de extinción. En este estudio, se midieron la fenología reproductiva y la depredación de semillas por las ardillas (Sciurus variegatoides) y lapas rojas durante marzo y abril 2011 en las playas de la costa Pacífica Central de Costa Rica. Los niveles de productividad y depredación de semillas se cuantificaron semanalmente para 111 almendros de playa, para evaluar la importancia del almendro de playa como fuente de alimento para la lapa roja y el grado de repartición de recursos entre los depredadores de semillas. La producción de semillas de los árboles fue alta (cerca de 194 272 semillas) y aproximadamente el 67% de las semillas fueron comidas por los depredadores, las lapas rojas consumen un estimado de 49% de las semillas, mientras que las ardillas consumen el 18%. Adicionalmente, se encontró evidencia de la repartición de recursos entre las ardillas y las lapas. Las lapas rojas prefieren alimentarse en el lado norte y el borde de la copa, mientras que las ardillas prefieren las regiones del sur y el interior de la copa. Ambas especies se comieron la mayoría de las semillas en la parte del árbol con lado al mar. A pesar de la situación de este árbol como una especie exótica, la playa de almendras parece ser un recurso importante para la recuperación de la población de lapas rojas. El recurso que produce este árbol debe tomarse en cuenta para continuar con los esfuerzos de reforestación en Costa Rica.

Scarlet Macaw (Ara macao, Psittaciformes: Psittacidae) Nest Characteristics in the Osa Peninsula Conservation Area (ACOSA), Costa Rica

The Scarlet Macaw (Ara macao) is an endangered species. In Costa Rica, the Scarlet Macaw population of the Central Pacific Conservation Area (ACOPAC, n =432 individuals) has undergone considerable study and has been used effectively as a flagship species for regional conservation. Costa Rica’s only other viable Scarlet Macaw population, located in the Osa Peninsula Conservation Area (ACOSA, n=800-1200 individuals), remains virtually unstudied. We studied ACOSA Scarlet Macaw nest cavities from February 19th to March 22nd 2006. Through informal interviews with park guards and residents, we found a total of 57 potential nests in 52 trees. Eleven nests were reported as frequently poached. Scarlet Macaws used 14 identified tree species, ten of which are unrecorded in Costa Rica. The most common nesting trees were Caryocar costaricense (n=12, 24%), Schizolobium parahyba (n=9, 18.0%), Ceiba pentandra (n=7, 14.0%) and Ficus sp. (n=5, 10.0%). We compare nesting characteristics to those recorded in ACOPAC. A combination of bottom-up and top-down strategies are necessary to ensure the Scarlet Macaw’s long-term success, including environmental education in local schools, community stewardship of active nests, and the advertisement of stricter penalties for poaching. Rev. Biol. Trop. 57 (1-2): 387-393. Epub 2009 June 30.

Scarlet Macaw (Ara macao) (Psitaciformes: Psittacidae) Parental Nest Visitation in Costa Rica: Implications for Research and Conservation

We studied temporal parental visitation of Scarlet Macaws (Ara macao) to six active nests in the Central Pacific Conservation Region of Costa Rica. Total parental time in the nest decreased significantly as the nestlings aged. Results provide guidelines to scientists for planning invasive activities to nestlings, such as placement of radio collars, or biological sample collection. These activities should be performed close to the end of the nesting period for minimal disturbance of parents and nestlings. Our results also provide information to aid wildlife guards in protecting active nests from poachers when chicks are close to fledging. Rev. Biol. Trop. 57 (1-2): 395-400. Epub 2009 June 30.

Estudiamos las visitas temporales de padres de la lapa roja (Ara macao) a seis nidos activos en el Área de Conservación del Pacifico Central (Costa Rica). El tiempo total que pasaron los padres en los nidos bajó en forma significativa en relación con el crecimiento de los pichones. Estos resultados pueden ayudar a los científicos a planear sus actividades "invasivas", tales como colocación de radio collares o colección de muestras biológicas. Las actividades deben coincidir con el final de la época de anidación para molestar menos a las aves. Nuestros resultados proveen información que puede ayudar a los guardaparques a proteger nidos activos cuando los pichones estan casi listos para salir.