Foraging tactics of a terrestrial salamander: Sustained yield in territories

Territorial red-backed salamanders (Plethodon cinereus) were given a high density of two prey types differing in size and caloric profitability. They chose a diet that approximated optimal foraging when they foraged in areas previously marked with advertisement pheromones. However, when foraging in previously unmarked or conspecific-marked areas they did not forage optimally, in a short time frame. In the latter two situations they evinced a lower rate of net energy due to their failure to specialize on the more profitable prey type and their longer intercapture intervals while time was devoted either to marking behaviour or submissive posturing. The salamanders appeared to opt for a strategy of sacrificing initial caloric yield until they had established marked territories and then switching to a higher sustained caloric yield. The data show that experimental handling of a predator per se can alter its foraging behaviour. Also a predator just initiating a territory may forage quite differently from one that has already established ownership, making the time frame during which observations are made important to understanding the predator's foraging strategy.