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Abiotic factors have been demonstrated to mediate predator-prey interactions in aquatic and terrestrial communities. For amphibians changes in pH, pollutants, temperature, ultraviolet-B, and moisture levels can alter behavioral, developmental, and physiological aspects of predator-prey relationships resulting in reduced survivorship. Some rhacophorid frogs deposit eggs as foam nests on vegetation overhanging water, presumably as an adaptive response to the risk of egg predation by aquatic animals. Terrestrial insects are known to feed on frog embryos in foam nests, and anecdotal observations in tropical East Asia and Southeast Asia suggested that predation of frog embryos by dipteran fly larvae may be higher in unshaded areas. To understand the role that shading may play in this relationship, I compared survival of embryos of the Brown Tree Frog (Polypedates megacephalus) infested by larvae of a calliphorid fly (Phumosia coomani) in shaded and unshaded conditions in a controlled field study. When foam nests were infested by flies, survival to hatching was more than 15 times higher in shaded than in unshaded nests. Less than 1% of frog embryos survived to hatching in unshaded, infested foam nests which contained twice as many fly larvae as shaded nests. These results combine to suggest that both colonization and predation by flies are higher in unshaded foam nests. The mechanism triggering increased colonization of unshaded nests is unclear, but warmer temperatures on the surfaces of unshaded foam nests may decrease hatching time for fly eggs, permitting fly larvae to move inside the foam nest more quickly and begin feeding on amphibian embryos. Although the risk of predation by calliphorid flies is higher for P. megacephalus in unshaded areas, the benefits of developing in warmer conditions, including faster embryonic and larval development and larger size at metamorphosis, may offset this risk. [ABSTRACT FROM AUTHOR]

Frogs and toads have species-specific repertoires of vocalizations that function in contexts related to reproduction. Although some 6000 anuran species have been described to date, we have comparatively few descriptions of their vocalizations, which are among their most conspicuous behaviors. Statistical descriptions of vocal repertoires are key to understanding the evolution of frog communication systems and play potentially important roles in anuran conservation and systematics. The primary objective of this study was to describe the vocal repertoire and calling behavior of the Ponmudi Bush Frog, Raorchestes graminirupes, a recently described species endemic to the Western Ghats of India. A secondar)' objective was to investigate patterns of individual variation in calling behavior and several potential sources of that variability, including temperature, body size, and physical condition. We analyzed 1000 calls from 25 males near Ponmudi in the State of Kerala. Males produced two distinct, pulsatile call types that were temporally organized in a hierarchical structure of short call groups and longer call bouts. The two call types differed primarily in call duration, amplitude envelope, and the number of pulses per call. The dominant frequency of both call types was significantly negatively correlated with body length, mass, and condition. Temporal properties were generally unrelated to male phenotype, and few call properties were related to temperature in our sample of recordings. Based on coefficients of variation (CV), dominant frequency exhibited less variability within and among individuals (CV < 4%) compared with temporal properties (e.g., 10% < CVs < 30%). We discuss diese results in relation to previous studies of vocal repertoires and call variability in other anurans. [ABSTRACT FROM AUTHOR]

A new species of rhacophorid frog of the genus Chiromantis is described from Phnom Samkos in the northwestern section of the Cardamom Mountains, Cambodia on the basis of having the following unique characteristics: green blood; turquoise bones; a thick, white line running from below the midsection of the eye onto the upper lip to the shoulder; and fingers III and IV being more than one-quarter webbed. It is further distinguished from its congeners by a unique combination of additional morphological and color pattern characteristics. This new species is the eighth potential endemic known from the Cardamom Mountains and underscores the need for continued field work in this remote section of Indochina. [ABSTRACT FROM AUTHOR]