Oceanic whitetip sharks (Carcharhinus longimanus ) are best known as inhabitants of the open seas. However, a new report by an US-led team of marine biologists has found that these apex predators regularly migrate to waters around the Bahamas.
The biologists say their study could have implications for shark conservation strategies on an international level.
Lead author Lucy Howey-Jordan, from the scientific tracking company Microwave Telemetry, Inc. Stated: “While the oceanic whitetip shark is one of the most severely overexploited shark species, it is also among the least studied because it lives much of its life far from land in the open ocean,” “Before this study and our ongoing research, very few of these sharks had been fitted with satellite tags, and the data we obtained will help establish new conservation measures.”
The research team attached tracking tags to one male and 10 female mature oceanic whitetip sharks near the Bahamas in May 2011 and recorded the sharks’ behavior over several different intervals. The tags transmitted their depth, water temperature and location for pre-programmed periods of time.
The team found that five of the sharks made long-distance travels far away from the chain of tropical islands, with one even traveling as far out as Bermuda. All of these were mature female sharks that eventually returned to the Bahamas, providing the first evidence of return-migration for these large marine predators.
The researchers also found that the sharks spent about 68 percent of their time in Bahamian waters, which is good news for conservationists since the Bahamas have strictly protected the sharks for the past two decades.
Oceanic whitetip shark. Picture by Jim Abernathy
The research team consisted of
- Lucy A. Howey-Jordan,
- Edward J. Brooks,
- Debra L. Abercrombie,
- Lance K. B. Jordan,
- Annabelle Brooks,
- Sean Williams,
- Emily Gospodarczyk,
- Demian D. Chapman
The paper can be read at:
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0056588
More info about the oceanic whitetip and population information and statistics can be found in the IUCN Red List, where this species is classified as ‘Vulnerable’ :
http://www.iucnredlist.org/details/39374/0
