TITLE

Behavioral evidence suggests facultative scavenging by a marine apex predator during a food pulse

AUTHOR(S)
Hammerschlag, Neil; Bell, Ian; Fitzpatrick, Richard; Gallagher, Austin; Hawkes, Lucy; Meekan, Mark; Stevens, John; Thums, Michele; Witt, Matthew; Barnett, Adam
PUB. DATE
October 2016
SOURCE
Behavioral Ecology & Sociobiology;Oct2016, Vol. 70 Issue 10, p1777
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
The ability of predators to switch between hunting and scavenging (facultative scavenging) carries both short-term survival and long-term fitness advantages. However, the mechanistic basis for facultative scavenging remains poorly understood. The co-occurrence of tiger sharks ( Galeocerdo cuvier) and green turtles ( Chelonia mydas) at Raine Island (Australia), provides an opportunity to examine a top marine predator's feeding mode in response to seasonal pulses in nesting turtles that offer both hunting and scavenging opportunities. Using satellite telemetry, we evaluated home range overlap between sharks and turtles and quantified their surfacing behavior around Raine Island during the turtle nesting season. We found core home range overlap to be highest during the nesting season. Both sharks and turtles spent significantly more time at the surface in areas of greatest range overlap closest to shore, where turtle density was highest. Both sharks and turtles showed decreased surfacing with increasing distance from Raine Island. Combined with published data on turtle demography at Raine Island, we propose the following: (1) sharks patrol the surface to increase scavenging opportunities on turtle carcasses and intercept weakened individuals after nesting; (2) healthy turtles may not perceive sharks as a major threat and/or other biological factors override anti-predatory responses; and (3) sharks during the nesting season may primarily scavenge on dead turtles individuals rather than actively hunt. Our study results and approach may be applicable to other situations in which direct observations of predator-prey interactions are limited. Significance Statement: Every animal encounters dead or dying resources, yet the role of facultative scavenging has been difficult to study, and thus largely overlooked in marine behavioral ecological research. Movement analyses of tiger shark and green turtle movement and surfacing behavior at Raine Island (Australia) suggest that facultative scavenging may be a prevalent, yet underappreciated, feeding strategy in tiger sharks. Our integration of behavioral ecology theory with multi-species electronic tagging provided a valuable approach for investigating predator-prey interactions in situations where direct observations are limited or not possible.
ACCESSION #
118060028

 

Related Articles

  • Distribution and feeding ecology of the Greenland shark ( Somniosus microcephalus) in Greenland waters. Nielsen, Julius; Hedeholm, Rasmus; Simon, Malene; Steffensen, John // Polar Biology;Jan2014, Vol. 37 Issue 1, p37 

    Greenland sharks are widely distributed and most likely a highly abundant predator in arctic waters. Greenland sharks have previously been considered scavengers, but recent studies suggest that Greenland sharks also predate on live prey. In this study, distribution and feeding ecology in...

  • bad rap. Carroll, Chris // National Geographic;Jun2005, Vol. 207 Issue 6, p50 

    Focuses on the African hyena. Undeserved reputation hyenas have as thieves and scavengers that subsist on the leavings of larger predators; How in reality larger predators often steal from the hyena; How predators like cheetahs often avoid confrontations with hyena.

  • Predators and parasitoids of egg sacs of the widow spiders, Latrodectus geometricus and Latrodectus hesperus (Araneae: Theridiidae) in southern California. Vetter, Richard S.; Vincent, Leonard S.; Itnyre, Amelia A.; Clarke, Daniel E.; Reinker, Kathryn I.; Danielsen, Douglas W. R.; Robinson, Lindsay J.; kabashima, John N.; Rust, Michael K. // Journal of Arachnology;2012, Vol. 40 Issue 2, p209 

    The brown widow spider, Latrodectus geometricus C. L. Koch 1841, is non-native to North America and has experienced an explosive range expansion in the first decade of the 21st century. Previously restricted to peninsular Florida, it is now well established in the southeastern United States and...

  • Chemosensory responses and foraging behavior of the seastar Pycnopodia helianthoides. Brewer, Reid; Konar, Brenda // Marine Biology;Jul2005, Vol. 147 Issue 3, p789 

    Chemical cues released by damaged or dead organisms can affect how and where benthic organisms feed. These cues may cause predators to act as opportunistic scavengers in lieu of their normal predatory role. A scavenger, as defined in this study, is an organism that consumes damaged and/or dead...

  • Feeding aggregations of sea stars ( Asterias spp. and Henricia sanguinolenta) associated with sea urchin ( Strongylocentrotus droebachiensis) grazing fronts in Nova Scotia. Scheibling, Robert E.; Lauzon-Guay, Jean-S├ębastien // Marine Biology;May2007, Vol. 151 Issue 3, p1175 

    Migrating feeding aggregations (or fronts) of sea urchins can dramatically alter subtidal seascapes by destructively grazing macrophytes. While direct effects of urchin fronts on macrophytes (particularly kelps) are well documented, indirect effects on associated fauna are largely unknown....

  • The noble cats and the big bad scavengers: effects of dominant scavengers on solitary predators. Krofel, Miha; Kos, Ivan; Jerina, Klemen // Behavioral Ecology & Sociobiology;Sep2012, Vol. 66 Issue 9, p1297 

    Scavenging is an important but poorly understood ecological process. Dominant scavengers can impose a selection pressure that alters the predator's fitness, morphology, behavior, and ecology. Interactions between ursids, likely the most important dominant scavengers in the Holarctic region, and...

  • SPOTTED HYENA. DEMING, ALISON HAWTHORNE // Orion Magazine;Sep/Oct2014, Vol. 33 Issue 4, p62 

    The article offers information on hyenas and their varieties, along with information on their scavenging and hunting activities. Topics discussed include Serengeti hyenas and their structure, anatomy of hyenas, and spotted hyenas and surplus killing. It mentions the behavior, mating and...

  • Sky Burial. Holmgren, Hoag // Gettysburg Review;Summer2005, Vol. 18 Issue 2, p241 

    The author narrates that rattling home on a dirt road one October afternoon, dust roiling behind the car, the author saw Gus, one of the neighborhood kids, standing in his backyard. He was transfixed, his gaze riveted to something the author could not see. The author's wife Leda and their two...

  • Linking northern fur seal behavior with prey distributions: the impact of temporal mismatch between predator studies and prey surveys. Kuhn, Carey E.; Sterling, Jeremy T.; Zeppelin, Tonya K. // Animal Biotelemetry;Aug2015, Vol. 3 Issue 1, p1 

    Background: An essential part of foraging ecology research is identifying how the distribution and abundance of prey influence predator behavior. However, in marine systems, temporal or spatial mismatches often exist between prey surveys and predator tracking periods, especially for species with...

  • A stable isotope approach to the eastern Weddell Sea trophic web: focus on benthic amphipods. Nyssen, Fabienne; Brey, Thomas; Lepoint, Gilles; Bouquegneau, Jean-Marie; De Broyer, Claude; Dauby, Patrick // Polar Biology;Apr2002, Vol. 25 Issue 4, p280 

    Stable isotope (13C/12C and 15N/14N) analyses were performed on 90 species belonging to different benthic communities sampled in the eastern Weddell Sea. The study focused on eight amphipod species whose isotopic composition was compared to their previously described respective gut contents....

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics