Right whale status, 2011

First published in the MLA Newsletter, December, 2011.

The MLA newsletter continues its series of articles on endangered whales and the laws in place to protect them. New whale rules to reduce the risk of entangling endangered whales in vertical lines will go into effect in 2012. The North Atlantic Right Whale report card, released by the North Atlantic Right Whale Consortium, is summarized below. 

Each fall the North Atlantic Right Whale Consortium issues an annual report card on the status of right whales on the East coast. The report card includes updates on the cataloged population of North Atlantic right whales, mortalities and entanglement events, and a summary of current management and research efforts of the previous year.

The ability to monitor North Atlantic right whales is dependent on the right whale identification database. Curated by the New England Aquarium, the database consists of over 500,000 slides, prints, and digital images collected during the 58,000 sightings of over 620 individual right whales photographed since 1935. Each year, 3,000 to 5,000 sightings consisting of 20-30,000 images are added to the identification database. Due to the lag time in processing data, the most recent estimate of the cataloged population available is for 2010.

In 2010, the best estimate of cataloged North Atlantic right whales was 490 individuals. This “best estimate” is based upon the number of photographed whales only and therefore should not be considered a population estimate. This estimate includes 456 cataloged whales that were presumed to be alive in 2010 because they were seen in that year, or at any time in the prior five years.

Reproduction: 2011

22 calves were born this year.

Average calving interval of 2011 moms was 3.78 years.

There were five first time mothers.

Deaths

Between November 1, 2010 and October 31, 2011, five right whale deaths were documented

Entanglements

There were 39 known entanglement sightings reported between November 1, 2010 and October 31, 2011, involving 15 cases/individuals, 11 of which were new cases.

Vessel strikes

Six right whales were sighted with new propeller wounds between November 1, 2010 and October 31, 2011. Additionally, one whale was discovered with new propeller wounds on February 20, 2010 which was not previously reported.