Navigation Links
Great white sharks
Date:4/10/2013

MIAMI April 9, 2013 Many terrestrial animals are frequently observed scavenging on other animals whether it is a hyena stealing a lion kill in the Serengeti or a buzzard swooping down on a dead animal. However, documenting this sort of activity in the oceans is especially difficult, and often overlooked in marine food web studies.

In a new study published in PLOS ONE titled, "White sharks (Carcharodon carcharias) scavenging on whales and its potential role in further shaping the ecology of an apex predator," Captain Chris Fallows from Apex Expeditions collaborated with University of Miami (UM) scientists Dr. Neil Hammerschlag and Austin Gallagher, to explore the behaviors of Great white sharks scavenging on dead whales in South Africa. The team documented as many as 40 different sharks scavenging on a carcass over the course of a single day, revealing unique social interactions among sharks.

The study summarized observations based on four scavenging events opportunistically observed over a 10 year period. In each multi-day observation, the team recorded daily evidence of social, aggregative and feeding behaviors observed in the waters off South Africa. They suggest that although the occurrence of coming upon a whale carcass may be sporadic, the shark populations are likely prepared to scavenge on them, and may even rely on their scavenging activities to supplement their regular feeding activities.

"Although rarely seen, we suspect that as white sharks mature, scavenging on whales becomes more prevalent and significant to these species than previously thought," said Hammerschlag, who is director of the R.J. Dunlap Marine Conservation Program at UM.

The team found that sharks showed a clear preference for scavenging on the blubber, probably because these high calorie meals can sustain the sharks for longer periods of time. Interestingly, though, the study also found that sharks showed an initial preference for feeding on the whale's fluke before moving on to feed on the rest of the carcass. The team also found that while scavenging on whales, they ceased hunting and feeding on seals, one of their primary natural prey.

"While scavenging on the whale, the sharks clearly showed a size-based pecking order," said Fallows. "The biggest sharks came right in, targeting areas of highest blubber content, while smaller sharks fed on areas with less blubber or kept their distance from the whale, mostly scavenging on pieces of blubber that drifted away from the carcass."

The paper reveals how the social and size structure of sharks at the carcass appeared to be influenced by environmental patterns. "The cues, such as the oils, emanating from this pulse of food are likely attracting much larger sharks over 4.5 meters from long distances to scavenge," said Gallagher. "These data provide some credence to the hypothesis that large white sharks may be swimming known ocean corridors looking for dead, dying, or vulnerable whales."

"By attracting many large white sharks together to scavenge, we suspect that the appearance of a whale carcass can play a role in shaping the behaviors, movements, and the ecosystem impacts of white sharks" said Hammerschlag. "These patterns may shed some light into the ecology of this often studied - yet still highly enigmatic - marine predator."


'/>"/>

Contact: Alexandra Bassil
a.bassil@miami.edu
305-284-1092
University of Miami
Source:Eurekalert

Related biology news :

1. Asian carp DNA not widespread in the Great Lakes
2. Notre Dame study finds Asian carp DNA not widespread in the Great Lakes
3. Obama calls Ben-Gurion U. brain research a great idea
4. Are survivors of childhood leukemia and lymphoma at greater risk of chronic fatigue as adults?
5. Paving the way for greater use of ancient medical knowledge
6. Speech emerges in children with autism and severe language delay at greater rate than thought
7. Environmental threat map highlights Great Lakes restoration challenges
8. Mapping effort charts restoration tack for Great Lakes
9. Grant furthers Mercyhurst research for human pathogens in Great Lakes
10. Notre Dame research reveals migrating Great Lakes salmon carry contaminants upstream
11. University of Michigan, Michigan State University award grants for Great Lakes climate change research
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/7/2017)...   MedNet Solutions , an innovative SaaS-based eClinical ... research, is pleased to announce that the latest release ... flexible and award winning eClinical solution, is now available ... is a proven Software-as-a-Service (SaaS) clinical research technology platform ... also delivers an entire suite of eClinical tools to ...
(Date:2/6/2017)... 6, 2017 According to Acuity Market ... border authorities to continue to embrace biometric and ... 2143 Automated Border Control (ABC) eGates and 1436 ... more than 163 ports of entry across the ... achieving a combined CAGR of 37%. APC Kiosks ...
(Date:2/2/2017)... 2, 2017   TapImmune, Inc. (NASDAQ: ... specializing in the development of innovative peptide and ... cancer and metastatic disease, announced today it has ... of a second clinical lot of TPIV 200, ... alpha. The manufactured vaccine product will be used ...
Breaking Biology News(10 mins):
(Date:2/16/2017)... 2017  ArmaGen, Inc., a privately held biotechnology ... severe neurological disorders, today reported preliminary evidence of ... company,s investigational therapy for the treatment of Hurler ... I, or MPS I). The initial results from ... today at the 13 th annual WORLD ...
(Date:2/16/2017)... PALM BEACH, Florida , February 16, 2017 ... vastly improving with the infusion of innovative telemedicine ... patient monitoring services that are experiencing a boom ... evolve with the advancement of technologies, services and ... Technologies Inc. (OTC: RQHTF) (TSX-V: RHT), Cellectar Biosciences, ...
(Date:2/16/2017)... ... February 16, 2017 , ... ... Dr. Kingsley Chin, professor and Harvard trained surgeon, completed the procedure on Monday, ... on a 55-year-old practicing female physician suffering from degenerative disc disease with radiculomyelopathy, ...
(Date:2/16/2017)... ... February 16, 2017 , ... ... Inc. has further extended its industry leading Biochemistry Services specifically targeting the ... cGMP techniques and methods for the biochemical and biosimilar characterization , ...
Breaking Biology Technology: