RESUMO
The comparative phylogeography of marine species with contrasting dispersal potential across the southern Caribbean Sea was evaluated by the presence of two putative barriers: the Magdalena River plume (MRP) and the combination of the absence of a rocky bottom and the almost permanent upwelling in the La Guajira Peninsula (ARB + PUG). Three species with varying biological and ecological characteristics (i.e., dispersal potentials) that inhabit shallow rocky bottoms were selected: Cittarium pica (PLD < 6 days), Acanthemblemaria rivasi (PLD < 22 days), and Nerita tessellata (PLD > 60 days). We generated a set of SNPs for the three species using the ddRad-seq technique. Samples of each species were collected in five locations from Capurganá to La Guajira. For the first time, evidence of a phylogeographic break caused by the MRP is provided, mainly for A. rivasi (AMOVA: ΦCT = 0.420). The ARB + PUG barrier causes another break for A. rivasi (ΦCT = 0.406) and C. pica (ΦCT = 0.224). Three populations (K = 3) were identified for A. rivasi and C. pica, while N. tessellata presented one population (K = 1). The Mantel correlogram indicated that A. rivasi and C. pica fit the hierarchical population model, and only the A. rivasi and C. pica comparisons showed phylogeographic congruence. Our results demonstrate how the biological traits of these three species and the biogeographic barriers have influenced their phylogeographic structure.
RESUMO
ResumenEn Colombia, C. acutus se encuentra catalogada en peligro crítico. Durante julio 2007, agosto 2008, junio y agosto 2009 y entre marzo y agosto 2010 y 2011, la población en Bahía Portete fue estudiada para evaluar la anidación y obtener la información necesaria para el ajuste de un programa de manejo acorde con la biología de la especie. Este estudio asumió la vinculación de la comunidad indígena Wayuü para emplear el modelo de acuerdo de conservación. Se realizaron transectos en toda la costa de la bahía para la búsqueda de nidadas. En la determinación de las áreas de importancia para la anidación, se registraron las características biométricas de los nidos, la biometría de huevos y crías, la fertilidad de huevos y eventos reproductivos. Como resultado se recorrieron 55.12 km, se determinaron cuatro zonas de importancia para la anidación, la de mayor importancia fue la isla Juyui. En todas las áreas de anidación, variables como la anidación colonial o gregaria y las variables ambientales fueron factores que afectaron el éxito de eclosión. El 37 % de los nidos estuvieron orientados hacia el norte y el 48 % fueron construidos en cercanía de Stenocereus griseus. La isla Juyui presentó los mayores porcentaje de arena (71.9 %, 71.44 %). El promedio de huevos por nido fue 28.42 ± 6.63. Los huevos presentaron un diámetro mayor promedio de 71.84 ± 3.54 mm y peso 81.54 ± 9.99 g. Las crías presentaron un promedio de longitud total de 25.47 ± 1.16 cm. El período reproductivo para este sector de Colombia, se inicia en marzo y culmina en agosto. Las pocas áreas de anidación y la fertilidad del 95 % sugieren la ejecución de un programa conservación para C. acutus en Bahía Portete.
Abstract:C. acutus is cataloged in critical danger in Colombia. We studied its population at Bahia Portete, in order to survey the nesting activities and to obtain valuable information for a conservation management program. This study was undertaken with the participation of the Wayuü community using the Agreement Conservation Model, and took place during July 2007, August 2008, June and August 2009, and March to August 2010 and 2011. Sampling surveys were made by the use of transects along the coast, in order to find nests. For each nesting area found, we recorded the nests biometrics, eggs and hatchlings, fertility of the eggs and reproductive events. We explored a total of 55.12 km, and determined four nesting areas. Colonial nesting and the environmental variables were factors that affected the hatchling success. From the total of nests found, 37 % were oriented towards North, and 48 % were built next to Stenocereus griseus. Juyui island substrate was mostly constituted by sand (71.9 %, 71.44 %). The average number of eggs by nest was 28.42 ± 6.63, the largest egg diameter was 71.84 ± 3.54 mm, the average nest weight was 81.54 ± 9.99 g, and the hatchlings presented an average length of 25.47 ± 1.16 cm. For this specific site in Colombia, the reproductive period begins in March and ends in August. The few areas of nesting and the 95 % fertility suggest the performance of a conservation management program for this species at Bahía Portete. Rev. Biol. Trop. 65 (1): 211-228. Epub 2017 March 01.
Assuntos
Animais , Reprodução/fisiologia , Jacarés e Crocodilos/fisiologia , Comportamento de Nidação/fisiologia , Valores de Referência , Estações do Ano , Comportamento Sexual Animal/fisiologia , Fatores de Tempo , Análise de Variância , Densidade Demográfica , Colômbia , Ecossistema , Baías , Ovos/estatística & dados numéricosRESUMO
C. acutus is cataloged in critical danger in Colombia. We studied its population at Bahia Portete, in order to survey the nesting activities and to obtain valuable information for a conservation management program. This study was undertaken with the participation of the Wayuü community using the Agreement Conservation Model, and took place during July 2007, August 2008, June and August 2009, and March to August 2010 and 2011. Sampling surveys were made by the use of transects along the coast, in order to find nests. For each nesting area found, we recorded the nests biometrics, eggs and hatchlings, fertility of the eggs and reproductive events. We explored a total of 55.12 km, and determined four nesting areas. Colonial nesting and the environmental variables were factors that affected the hatchling success. From the total of nests found, 37 % were oriented towards North, and 48 % were built next to Stenocereus griseus. Juyi island substrate was mostly constituted by sand (71.9 %, 71.44 %). The average number of eggs by nest was 28.42 ± 6.63, the largest egg diameter was 71.84 ± 3.54 mm, the average nest weight was 81.54 ± 9.99 g, and the hatchlings presented an average length of 25.47 ± 1.16 cm. For this specific site in Colombia, the reproductive period begins in March and ends in August. The few areas of nesting and the 95 % fertility suggest the performance of a conservation management program for this species at Bahía Portete.