Dasha beluga whale: Removal of transmitter attached in 2009

Dasha beluga whale: Removal of transmitter attached in 2009

24 April 2014

Acting under the programme for study of the distribution range and seasonal migrations of the beluga whale, which is under way with support from the Russian Geographical Society, the scientists of the RAS Standing Expedition have attached transmitters to over 20 white whales since 2009. In July 2009, Vladimir Putin helped to attach a transmitter to a white whale named Dasha off Chkalov Island in the Sakhalin Gulf of the Sea of Okhotsk. For 226 days, scientists received information about the migration of Dasha and other whales. This helped them to establish when the whales migrate from their summer locations, which routes they choose to swim to their winter aggregation sites and the depth at which they feed in different seasons. On 8 March 2010, the transmitters that were simultaneously attached to Dasha and another beluga whale fell silent. The scientists knew nothing about them for three years.

 

In the summer of 2013, a group of scientists from the Institute of Environmental and Evolution Studies (IEES) and the Marine Mammal Council (MMC) were studying beluga aggregations in the Sakhalin Gulf. They measured live-captured animals, evaluated their condition and collected samples for medical and biological analyses. As they were doing this, they saw a whale with scars left in the place where a transmitter was attached. Several days later, they live-captured a beluga whale with an attached transmitter. It was a 395-cm-long female whale that looked healthy and seemed peaceful. The transmitter was securely attached, with only the foremost of the three fastenings missing. The scar in its place seemed to have healed well and did not look inflamed. A 2 mm steel stub was left of the antenna. Since the transmitter was no longer functioning, the scientists decided to remove it and to release the whale back into the sea.

 

Back in Moscow, the IEES scientists studied the blood sample collected from that whale and did a molecular and genetic analysis of its skin sample. A designer of satellite transmitters with the ES-PAS company disassembled the transmitter removed from the beluga and established its identification number. The results of the genetic analysis and the transmitter’s identification number proved that they were taken from Dasha, the beluga whale which was first live-caught in July 2009. The stub in the place of the antenna indicated that Dasha might have been among the group of whales that were likely caught in ice on 8 March 2010. It appears that Dasha and her partner – the whale with scars from the transmitter – managed to escape from the ice trap.

 

Every summer, the beluga whales return to the site where they were born and where they also give birth to their calves. Repeated sightings of the same whales off Chkalov and Baidukov islands in the Sakhalin Gulf show that the annual live capturing of whales there should be conducted very carefully, because live-capture teams could be catching animals from the part of the group for which the area off the two islands was the home site. Scientists are not worried that Dasha may die in an ice trap but that she could be caught by one of the numerous live-capture groups.

 

The intensity of live-capturing increased threefold in 2013, with three teams with nets more than 3 km long, modern equipment and fast boats stalking whales near Dasha’s summer “home.” The scientists are also worried about the increased media activity of the live-capturing groups, who are encouraged by rising international interest in buying Russian beluga whales.