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Alaska: Scientists Tag North Pacific Right Whales |
| September 14, 2004 |
 | A north Pacific right whale surfaces in the Bering Sea on August 10, 2004. This is one of two whales on which satellite tags were deployed.
Photo: John Durban, NMML |
Scientists from the National Marine Fisheries Service (NOAA Fisheries) recently tagged two North Pacific right whales in the Bering Sea, hoping to discover where the whales spend their winters.
The researchers are now tracking the extremely rare and endangered whales by satellite, a more efficient method than visual and auditory observations.
“We were lucky with weather, whales, and everything else,” said NOAA scientists Dr. Paul Wade. “It was our third day in the right whale box, and we had beautiful, flat calm weather.”
The ‘box’ is an area in the eastern Bering Sea where North Pacific right whales are known to gather in the summer.
Acoustics researchers had deployed a sonobuoy (an underwater listening device) at noon on the day of discovery, and heard distant whale calls. The calls gave the scientists a bearing that enabled them to find two right whales.
According to Wade, the whales were fairly large. The larger of the two was likely an adult, and the second whale was slightly smaller, and likely a small adult or sub-adult. Scientists placed tags on the whales that enabled them to be tracked by satellite.
The North Pacific right whale is one of the most endangered whale species in the world because it was severely depleted by over-exploitation in the 1800s. Following international protection in the 1931, sighting records indicate that right whales were a small but recovering population in the eastern North Pacific. However, illegal takes of right whales by commercial whaling vessels from the Soviet Union in the 1960’s apparently reduced the population to a precariously low level.
Since that time, sightings of right whales have been extremely rare in the eastern North Pacific. In fact, there have only been 15 documented winter sightings of right whales in the eastern Pacific since 1900.
The North Pacific right whale tagging project was initiated in August 2004 to discover where North Pacific right whales spend the winter. Although North Atlantic right whales and southern-hemisphere right whales are known to gather in sub-tropical coastal areas in winter (particularly females with newborn calves), no wintering or calving area has ever been discovered for North Pacific right whales.
The batteries in the transmitter tags can last for a year or more, but scientists hope the tags continue to function for at least five months.
“It will be tremendous if we can track these whales to their migratory destination,” Wade said. “We have very little idea where these whales go in the winter, other than somewhere south, and we don’t know what route they take.”
Signals from both tags have been received by satellites, and one tag in particular has provided 31 locations spread over eight different transmission days, all in the southeast Bering Sea, with the most recent locations occurring on September 10. To save battery life, the tags are configured to transmit only every third day.
Further information on the North Pacific right whale tagging project, including photographs and a map of locations of the tagged whales will be posted on the National Marine Mammal Laboratory's website. The map on the website will be periodically updated as additional locations become available.
Source: Vancouver Aquarium Marine Science Centre
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