October 13, 2010

Female Humpback Sets World Distance Record

A female humpback whale has broken the world record for longest distance ever traveled by a mammal, covering more than 6,000 miles from the Atlantic Ocean to the Indian Ocean while searching for a mate, according to a new study published in the journal Biology Letters.

The whale in question was originally photographed in the midst of other whales at a breeding ground off of the southeastern coast of Brazil in August 1999. Two years later, in September 2001, the same whale--whose identity was confirmed because of a pattern of spots and the distinctive shape of its tail, according to AFP reports--was spotted near Madagascar.

"The minimum travel distance between these locations is greater than 9800 km (6125 miles), approximately 4000 km (2485 miles) longer than any previously reported movement between breeding grounds, more than twice the species' typical seasonal migratory distance and the longest documented movement by a mammal," the research team, which was led by Dr. Peter Stevick from the College of the Atlantic in Maine, wrote in their study.

"It is unexpected to find this exceptional long-distance movement between breeding groups by a female, as models of philopatry suggest that male mammals move more frequently or over longer distances in search of mating opportunities," they added. "While such movement may be advantageous, especially in changeable or unpredictable circumstances, it is not possible to unambiguously ascribe causality to this rare observation. This finding illustrates the behavioral flexibility in movement patterns that may be demonstrated within a typically philopatric species."

Furthermore, according to Stevick and his colleagues, the discovery marks the first time that humpbacks, also known as Megaptera novaeangliae, have veered away from traditional migratory patterns between the northern and southern latitudes. This marks the first evidence that the species could also swim between eastern and western longitudes, which according to the AFP "could lead to a rethink of the species' genetic profile, which in turn has an impact on conservation."

When asked about the possible path traveled by the whale, Dr. Stevick told BBC News Science and Nature Reporter Victoria Gill, "If I had to guess, I'd say this animal did a normal migration to the Antarctic [to feed] and went to Madagascar from there"¦ If I were to draw a track for it, it would be from Brazil to the Southern Ocean and from there into the Indian Ocean."

"We're hopeful we will see this animal again, or see other animals doing related things," he added.


On the Net: