Habitat destruction and alteration is the leading contributor to global declines in biodiversity. Among declining vertebrate groups including mammals, birds, fish, and reptiles, amphibians are experiencing the sharpest declines world wide. Knowledge of juvenile amphibian dispersal and habitat selection remains one of the greatest missing components in management plans for amphibian populations.  As juvenile salamanders emerge and disperse away from their natal ponds they must avoid desiccation and risk of predation by selecting suitable habitats with the aid of olfactory cues. The scent of rotting leaves for example could be an indicator of the moist forest floor habitat preferred by Spotted Salamanders, Ambystoma maculatum. Selection of these same cues in the context of habitat alteration such as clear-cutting, could be disadvantageous. There is likely a lag period in which the substrate of recently cut forest retains its original olfactory cues, thus attracting salamanders into an inhospitable sink. Juvenile salamanders dispersing during an overcast rainy night could be fooled into selecting habitat which greatly increases there chance of desiccation and mortality.

 I am interested in investigating juvenile dispersal at several experimental levels, including laboratory tests to identify olfactory cues, field enclosure experiments to reveal microhabitat preferences, and population level studies at experimental forestry plots at our LEAP sites. Since May 2007, I have been implementing a marked recapture experiment with juvenile Ringed Salamanders (Ambystoma annulatum), Spotted salamanders (Ambystoma maculatum), and Green Frogs (Rana clamitans) at the Daniel Boone Conservation Area in Warren County, MO.

See poster [poster ppt] of current research on dispersal.

Osbourn, M.S., D.J. Hocking, C.A. Conner, W.E. Peterman, and R.D. Semlitsch. 2009. Use of fluorescent visible implant Alphanumeric tags to individually mark juvenile ambystomatid salamanders. Herpetological Review  (in press)