Figure 1.
Scavenging occurs in virtually all food-webs and habitats.
(A) a polar bear (Ursus maritimus) eating flesh from a narwhal whale carcass (Monodon monoceros) (Photo: Jeff W. Higdon/DFO); (B) an Ibiza wall lizard (Podarcis pityusensis) scavenging on fish scraps leftover from another predator (Photo: Nate Dappen/Day’s Edge Productions); (C) a black backed jackal (Canis mesomelas) scavenges on a zebra (Equus quagga) kill (Photo: Chris Fallows); (D) lappet faced vulture (Torgos tracheliotos) and white backed vultures (Gyps africanus) scavenge on an elephant kill (Photo: Chris Fallows); (E) A spotted hyena (Crocuta crocuta) removes flesh from a long-dead ungulate (Photo: Chris Fallows); (F) red weaver ants (Oecophylla smaragdina) gathering to feed on a dead African giant snail (Achatina fulica) (Photo:Narasha Mharte).
Table 1.
White sharks scavenging from two species of whales based on four separate accounts in False Bay, South Africa.
Figure 2.
Regression of wind speed and maximum shark size observed at all scavenging events in the present study.
Table 2.
Model diagnostics for generalized linear models for Poisson distributed data modeling shark occurrence during whale carcass scavenging forays.
Table 3.
Summary results of the best model the using Poisson regression in Table 2 to examine effects of biological and environmental variables on shark occurrence during scavenging forays on the two whale carcasses.
Figure 3.
Examples of selective, facultative scavenging by white sharks on various whale carcasses in South Africa.
(A) 4 m white shark removing and consuming a near-term fetus from a Bryde’s whale carcass; (B) white shark scavenging on caudal peduncle and fluke of a Bryde’s whale; (C) impression of a white shark bite on whale carcass through dermal, subcutaneous and blubber layer; (D) a white shark removing blubber around the jaw of a southern right whale carcass.
Figure 4.
Examples of unique behaviors employed by white sharks during scavenging forays on whale carcasses in False Bay, South Africa.
(A–B) A 4.5 m white shark removes a 20 kg chunk of flesh, sinew and blubber by performing lateral headshakes without employing protective ocular rotation.
Figure 5.
A comparison of mean shark predations on seals before, during and after the occurrence of a whale carcass at Seal Island.
Data examined before and after were collected over a two week period. Data were pooled across whales (#1, #2, #4). Predation data (mean±SE) were not collected nor analyzed for the period following the occurrence of whale #4. Differences in lower case letters denote statistical differences (p<0.05). Numbers in parentheses indicate number of observational days. Error bars represent 1 standard error.
Figure 6.
Activation and regulation of community-wide consumer food-web catalyzed via pulse of a whale carcass in False Bay, South Africa.
Diagram showing range of scavengers on a whale carcass at the surface (above dotted line) and when the carcass sinks to the seafloor (bottom dotted line) following removal of blubber by white sharks.