30 June 2016

Rare Sowerby’s Beaked Whale washes up in New Brunswick

Canadian Wildlife Health Cooperative

On June 13, 2016, the carcass of an adult male Sowerby’s beaked whale (Mesoplodon bidens) had been found in the Baie des Chaleurs, near Escuminac, Québec. The carcass was subsequently carried out by the tide but washed up again near Campbellton, New Brunswick. According to Don McAlpine, curator of the New Brunswick Museum (NBM), this is the first confirmed occurrence for this species in the province. The whale was towed approximately 0.25 km to a more accessible location for loading on a flatbed truck. The whale was delivered to the Canadian Wildlife Health Cooperative (CWHC-Atlantic) at the Atlantic Veterinary College in Prince Edward Island on June 17th.

On June 18th, a necropsy of the Sowerby’s whale was performed, lead by Dr. Pierre-Yves Daoust (CWHC) who was accompanied by Darlene Weeks and Fiep de Bie (CWHC), Drs. Shannon Martinson and Nicole Kaiser (AVC), Don McAlpine (NBM) and many veterinary students. The whale weighed approximately 1,059 kg and measured 4.75 m in length. The carcass was moderately decomposed with all internal organs intact. It was found to have an empty stomach, therefore it had not fed before death. The cause of death is still pending but at the time of necropsy, there was no obvious reason such as trauma or entanglement in fishing gear, to account for its demise.

The Sowerby’s beaked whale is a small to medium toothed whale, thought to be the most northern species of beaked whale in the North Atlantic. Very little is known about their biology, distribution or abundance as at-sea sightings are few. Their diet is believed to consist of deep sea fish and squid, and they are presumed to be deep diving whales. In Canada, Sowerby’s beaked whales were listed as Special Concern on the Species At Risk Act in 2011. Research suggests that beaked whales are sensitive to underwater noise pollution such as boat traffic, drilling, military sonar or seismic surveying. Whales exposed to acute noise may become disoriented or have abnormal dive patterns that can lead to mass strandings. The Department of Fisheries and Oceans recently released a draft Management Plan for Sowerby’s beaked whales. It is available for public review until August 8, 2016.