Use of Experimental Enclosures to Examine Foraging Success in Water Snakes: a Case Study
Vegetation structure is an important component of habitat that may affect the outcome of a predator-prey interaction. Studies of fish have focused on how habitat structure affects a predator's ability to capture prey (Crowder and Cooper, 1982; Savino and Stein, 1982; Nelson and Bonsdorff, 1990). Collectively, the results indicate either that thresholds of structural complexity exist, below or above which predation rates are hindered (Nelson, 1979; Heck and Orth, 1980), or that prey capture rate decreases monotonically as habitat complexity increases (Nelson and Bonsdorff, 1990). Generally, a stable supply of prey is available in habitats of optimal complexity, where foraging success (prey captured per unit time) is highest (Royama, 1970; Heck and Crowder, 1991). Foraging behavior may change from that of an ambush predator in densevegetation to that of active pursuit in lower vegetation densities in order to maintain a constant capture rate (Savino and Stein, 1982). Here, we present a protocol for experimentally examining the effects of varying structural complexity on predator-prey interactions using a snake as the predator. We test our methods by observing the mangrove salt marsh snake, Nerodia clarkii conlpressicauda (Lawson et al., 1991), foraging in an environment which simulates field conditions.
Mullin, Stephen J. and Mushinsky, Henry R., "Use of Experimental Enclosures to Examine Foraging Success in Water Snakes: a Case Study" (1997). Faculty Publications. Paper 122.