The Commander Islands Nature and Biosphere Reserve started research of the harbor seal – far eastern subspecies of the common seal, which is included in the Red Book of Russia. On September 15, we installed a satellite tag on the first out of five animals in Staraya Gavan Bay on Bering Island. The resting four are still to be caught, tagged and let free. Within a year the devices will show the travels of the animals and depth of their dives.
It is the first time for the nature reserve team to install satellite tags on marine mammals. Evgeny Mamaev, Deputy Director for Science, manages the work. From 1992 to 1994, he participated in catching and tagging of a larga seal on Kamchatka, where he gained valuable practice experience and skills to use today.
This time our team had a valuable helper – commander of Federal Security Service checkpoint on Bering Island. Border guards are also responsible for control over conservation of water bio resources, therefore they sometimes work together with the nature reserve during research and protection activities.
Satellite tag used for tagging a harbor seal
The animal was caught in Staraya Gavan Bay. The young male is strong, weights 80 kg and was quite displeased by the amount of attention. He came back into the water with the device attached to his back.
We plan to install tags on four more animals until the end of the year. They will be caught on Toporkov Island, Severo-Zapadnoye rookery and Buyan Bay. Five more animals will be taken samples for genetic research and to learn the level of heavy metals pollution of the water area of the islands.
The only attempt to satellite tag the harbor seal before was taken in 1995. That time Russian and the US scientists tagged two animals on Bering Island coast, though they did not receive the data.
Devices have evolved and now they upload the data directly to the satellite. Moreover, the depth the animal choose and how much time it spend on land and in the sea.
Harbor seal is a strong animal. A big team is an advantage
Harbor seal is one of the least researched seals in Russia. “One would think that the harbor seal is also near people, live near the Kuril Islands, Kamchatka and the Commander Islands – about a half of their population lives here – so the animals should be well known. Nevertheless, we lack data about their ecology and biology. We hope that our research will bring some interesting information for the science,” said Evgeny Mamaev.
It is believed that the harbor seal is tied to the Commander Islands for the whole life. However, its relative from the western coast of the USA, leave their reproductive grounds in Autumn and Winter for fishing.
We still do not know if harbor seals can leave their home islands and travel far away. Scientists also have no information about their travels from one rookery to another along the coast. “ The main haul-outs are on Toporkov Island and Bering Island: Buyan Bay, Staraya Gavan and Tonky Cape. Probably the animals are attached to their place of birth and lead the whole life there, for example on Toporkov Island. This mystery will be solved only after our research,” said Evgeny Mamaev.
The first harbor seal to be tagged was called Pioneer. Safe and sound with the tag on his back he returned to the sea, where he will transmit data to the satellite
The Commander Islands Nature Reserve persistently researches local population of harbor seals from 2017. We count the animals with drones. It is a valuable tool to have the exact number of individuals. This season we counted the animals for the first time on Medny Island. It gives us a full picture of the number of adults and pups on all the Commander Islands. The next stage is to tag. We will receive the results in 2020.