TY - JOUR
T1 - Foraging tactics of an ambush predator
T2 - the effects of substrate attributes on prey availability and predator feeding success
AU - González-Bernal, Edna
AU - Brown, Gregory P.
AU - Cabrera-Guzmán, Elisa
AU - Shine, Richard
PY - 2011/7
Y1 - 2011/7
N2 - The foraging sites selected by an ambush forager can strongly affect its feeding opportunities. Foraging cane toads (Rhinella marina) typically select open areas, often under artificial lights that attract insects. We conducted experimental trials in the field, using rubber mats placed under lights, to explore the influence of substrate color and rugosity on prey availability (numbers, sizes, and types of insects) and toad foraging success. A mat's color (black vs. white) and rugosity (smooth vs. rough) did not influence the numbers, sizes, or kinds of insects that were attracted to it, but toads actively preferred to feed on rugose white mats (50% of prey-capture events, vs. a null of 25%). White backgrounds provided better visual contrast of the (mostly dark) insects, and manipulations of prey color in the laboratory showed that contrast was critical in toad foraging success. Insects landing on rugose backgrounds were slower to leave, again increasing capture opportunities for toads. Thus, cane toads actively select backgrounds that maximize prey-capture opportunities, a bias driven by the ways that substrate attributes influence ease of prey detection and capture rather than by absolute prey densities.
AB - The foraging sites selected by an ambush forager can strongly affect its feeding opportunities. Foraging cane toads (Rhinella marina) typically select open areas, often under artificial lights that attract insects. We conducted experimental trials in the field, using rubber mats placed under lights, to explore the influence of substrate color and rugosity on prey availability (numbers, sizes, and types of insects) and toad foraging success. A mat's color (black vs. white) and rugosity (smooth vs. rough) did not influence the numbers, sizes, or kinds of insects that were attracted to it, but toads actively preferred to feed on rugose white mats (50% of prey-capture events, vs. a null of 25%). White backgrounds provided better visual contrast of the (mostly dark) insects, and manipulations of prey color in the laboratory showed that contrast was critical in toad foraging success. Insects landing on rugose backgrounds were slower to leave, again increasing capture opportunities for toads. Thus, cane toads actively select backgrounds that maximize prey-capture opportunities, a bias driven by the ways that substrate attributes influence ease of prey detection and capture rather than by absolute prey densities.
KW - foraging success
KW - prey choice
KW - prey selection
KW - Bufo marinus
KW - sit-and-wait predation
UR - http://www.scopus.com/inward/record.url?scp=79958792133&partnerID=8YFLogxK
U2 - 10.1007/s00265-011-1147-9
DO - 10.1007/s00265-011-1147-9
M3 - Article
AN - SCOPUS:79958792133
SN - 0340-5443
VL - 65
SP - 1367
EP - 1375
JO - Behavioral Ecology and Sociobiology
JF - Behavioral Ecology and Sociobiology
IS - 7
ER -