Prey Capture Success by Established and Introduced Populations of the Venus Flytrap (Dionaea muscipula)

Abstract

We examined whether the ecological function (i.e., prey capture) of a rare, endemic carnivorous plant, Venus flytrap (Dionaea muscipula), was maintained in managed habitats along the sand rims of Carolina bay wetlands at a preserve in the coastal plain of South Carolina, U.S.A. We hypothesized that prey capture would be similar between established and introduced plants because environmental conditions were similar. Number of traps, trap length, trap width, and prey length did not significantly differ between introduced and established populations, and most indicators of prey capture success significantly favored plants growing in introduced sites. Plants in introduced sites had almost 10% more closed traps, had significantly more traps with prey, had more traps with multiple prey items, and had a greater proportion of closed and total traps containing prey. When combined across sampling dates, ants and spiders composed the majority of captured invertebrates; spiders predominated in established sites while ants predominated in introduced sites. Prey availability on one date at a subset of sites was significantly greater in introduced sites. Our data supported the effectiveness of the clearing and transplanting restoration activity for Venus flytraps by showing that individual plants growing in introduced sites have similar structure and function as those in established sites. Consistently greater prey capture success by introduced plants likely contributed to their growth, although underlying reasons for differences in prey capture between introduced and established plants remain uncertain. Evaluating prey capture of carnivorous plant populations provides insight into mechanisms underlying restoration success.