DENSITY AND PHENOLOGY OF NOTOPHTHALMUS VIRIDESCENS DORSALIS IN A NATURAL POND
1988; Herpetologists' League; Volume: 44; Issue: 2 Linguagem: Inglês
ISSN
1938-5099
AutoresReid N. Harris, Ross A. Alford, Henry M. Wilbur,
Tópico(s)Freshwater macroinvertebrate diversity and ecology
ResumoA natural pond in the Sandhills Region of the Upper Coastal Plain of North Carolina was sampled for 3 yr to document variation in density and reproductive phenology of adult and larval Notophthalmus viridescens dorsalis. Adult densities were highest in late winter and spring when transforming efts were entering the pond and adults were reproductively active. Adult populations in the shallow areas of the pond declined to low levels in the summer. The timing of this decline varied among years. Emigration out of the pond rather than mortality or movement to deep regions of the pond is the most likely explanation for this decline. Larval populations of Notophthalmus increased rapidly in May and June and then declined from July through autumn due to mortality and metamorphosis to the eft stage. The density of adult newts and newt larvae was high in 1982 and 1983, but low in 1984. Size at metamorphosis in newts was inversely associated with larval density between years, in agreement with density-dependent growth observed in experimental populations. Larvae were spatially segregated by size in 1983 but showed less segregation in 1984. The temporal overlap in occupancy of the pond by adult newts and larval newts varied between years.
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