Seasonal Reproduction of a Neotropical Frog, the Cave Coquí (Eleutherodactylus cooki)

Abstract

The aim of this study was to evaluate factors contributing to seasonal reproductive variation in a Neotropical frog, the Puerto Rican cave coquí (Eleutherodactylus cooki). There was a relatively small seasonal variation in ambient temperature and relative humidity in the caves occupied by E. cooki. Nonetheless, the reproduction of E. cooki was strongly seasonal, with clutches produced from March to November, and no additional clutches deposited from December to February. This seasonal reproductive pattern may reflect a response to small changes in the thermal environment, because the frequency of clutch production and number of clutches deposited per nest site increased when air temperature was warmest (during the middle of the breeding season). Clutches occurred singly (71% of all clutches) or in groups of two (23%), three (6%), or four (< 1%). The median clutch size was 15 (range = 1–29). Significant egg mortality occurred, despite male attendance of nest sites. The average rate of egg mortality was 16% per week. Extrapolating to a hatching period of 3.5 weeks, 44% of produced eggs survived to hatching. It appears that combined effects of weak environmental variation, clutch predation, and male parental care substantially influence the reproductive output of E. cooki.