Right Whales tagged for first time to help solve mystery
For the first time satellite tags are being used to remotely track Southern Right Whales from their breeding/calving grounds in the sheltered bays of Península Valdés, Argentina, to unknown feeding grounds somewhere in the western South Atlantic.
It is hoped the results from the study will help solve why more than 400 Southern Right Whale calves have died between 2003-2011.
Different hypotheses put forward for this mortality include disease, certain types of contaminant, and harassment and wounding by kelp gulls, a frequent occurrence in Península Valdés.
Over the past month, a team of top scientists from a range of organisations, including the Wildlife Conservation Society (WCS), the Aqualie Institute of Brazil and the National Oceanic and Atmospheric Administration (NOAA) have succeeded in affixing satellite transmitters to five Southern Right Whales in Golfo Nuevo.
This area is one of the two protected gulfs of Península Valdés and an important breeding ground for southern right whales. The team selected calving females and solitary juveniles so they can glean insights into habitat use and migratory movements for different sex and age groups.
“Over the last several centuries, and as recent as the 1960s, southern right whales were hunted, at times close to the verge of extinction. But they have now managed to rebound in numbers thanks to protected refuges such as Península Valdés,” said Dr. Martín Mendez, Assistant Director of WCS’s Latin America and the Caribbean Program.
“The recent increase in mortality is being caused by something that remains unsolved. Determining where the whales go to feed may offer clues to solving this complex question.”
So far the data received shows that two of the five whales have remained in the waters of Golfo Nuevo, while the other three have already left the bay. One of the animals is currently in deep waters of the South Atlantic, one has been spending its time over the continental shelf, and another has moved into deep offshore waters, but has returned to the continental shelf break.
“As the tags continue to transmit, we hope our whales lead us to new insights about their lives in the vastness of the South Atlantic and provide possible clues related to the die-off,” said Dr. Howard Rosenbaum of WCS’s Ocean Giants Program.