Once believed to be the “right” whales to hunt, the endangered North Atlantic right whale (Eubalaena glacialis) population has been plummeting for at least the last eight years. The latest estimate stands at a mere 411 individuals.
Right whales are found in U.S. and Canadian Atlantic waters. Their distribution in the western North Atlantic spans the Gulf of St. Lawrence all the way down to Florida. Their main prey, Calanus finmarchicus, a tiny zooplankton from the copepod subclass, is now found in the Gulf of St. Lawrence in higher abundance than in their traditional habitat, due to warming waters—and so are they. However, being a non-traditional feeding ground, there were not any protective measures in place in the Gulf of St. Lawrence until 2017.
Absence de vie nouvelle
2018 started with another alarming situation: research teams did not see any new calves for the first time in decades during the breeding season from December to March and none even after.
Calving rates of the North Atlantic right whales have been on a decline for the last few years. Entanglement and fluctuating prey availability add stress to the almost 71 remaining breeding females. Additionally, recent studies found that their calving intervals have increased from four years to 10.
Des efforts sans précédent
With nearly half of the population seen in the Gulf this year, researchers left no stone unturned with their collective conservation efforts. Fisheries and Oceans Canada (DFO) has been introducing temporary and permanent fishery closures in the Gulf and Maritime regions all throughout the year. With combined projects from DFO, Dalhousie University, Canadian Armed Forces, Canadian Whale Institute, National Oceanic & Atmospheric Administration (NOAA), and the New England Aquarium, aerial and vessel surveillance and acoustic monitoring has also been in place in the whales’ critical habitat and beyond in order to document their changing distribution and alert mariners of their presence.
Furthermore, technological advancements are on the rise to combat the two main risks to the survival of this species: entanglement and ship strikes. For instance, a small Halifax-based business, called Ashored Innovations, is working with local fishermen to develop rope-less fishing gear to eliminate the use of vertical lines, which will also help other species that are at risk for entanglement. Ocean Tracking Network’s Slocum gliders acoustically detect right whales as well as their prey movement to help with fishery management and shipping traffic changes around Nova Scotia.
The New England Aquarium is working on a project to simulate right whale entanglements to better understand them and tackle the problem. They are also part of the Ropeless Consortium that aims to eliminate vertical lines from the water column—a death trap for right whales. Trials for various new technologies have already begun off California and Massachusetts.
Three documented cases of mortalities occurred in the U.S. waters this year; it is in line with the average mortality rate of the past 15 to 20 years. On the other hand, there have not been any documented right whale deaths in Canadian waters.
After feeding in the northern latitudes, right whales are now migrating south along the eastern seaboard towards their breeding grounds. Their population will continue to dwindle unless new calves are born in the upcoming breeding season. Research teams from various organizations will start their monitoring efforts for the 2018-2019 breeding season starting January, and we will continue tracking the situation.
Here are the important events from 2018:
January 22: First carcass of the year was spotted floating 80 nautical miles east of Virginia Beach. It was identified as a female right whale (#3893: 10-years old). She died of chronic entanglement and had gear akin to that used in the Canadian snow crab fishery attached to her.
April 12: The Center for Coastal Studies team attempted to disentangle Kleenex (#1142), an adult female right whale, who has been entangled for the last three years. She was seen in the southern Gulf of St. Lawrence by the NOAA Fisheries aerial survey team in June and July, and still had a rope wrapped around her head. Her condition continued to decline every time she was observed.
April 28: Following acoustic detections of a right whale in the Gulf of St. Lawrence, Transport Canada introduced speed restrictions for the western Gulf. Vessels 20 metres and more in length were not permitted to exceed 10 knots. Waters around Anticosti Island were also subject to speed restrictions when whales were spotted. Noncompliance could lead to fines of $6,000 up to $25,000.
May 12: An 8-year-old female right whale (#4091) was reported entangled east of Cape Cod, United States. She has not been seen since.
May 16: DFO spotted the first right whale off the coast of Cape Breton, Nova Scotia during an aerial surveillance flight.
July 13: A male (#3312-born in 2003) right whale was found entangled near Miscou Island, New Brunswick during a surveillance flight. The individual was not seen again.
July 30: A second male (#3843: 10-years-old) became entangled and was reported 22 nautical miles east of Grand Manan dragging an orange buoy behind it. It looked emaciated.
August 06: #3843 was disentangled successfully after a joint effort by DFO, Campobello Whale Rescue Team, Grand Manan Whale & Seabird Research Stations, and the Marine Animal Response Society.
August 20: Another right whale was reported entangled east of Miscou Island, New Brunswick. DFO monitored the individual and observed it surfacing without gear. The individual had successfully freed itself from the gear.
August 25: Second carcass was found. It was an unidentified young right whale (about 1.5-years old) is found dead south of Martha’s Vineyard near Nantucket, Massachusetts. Probable cause of death: entanglement and drowning. This individual was likely one of the five calves born over the 2016-2017 breeding season.
October 14: A third carcass was found floating in U.S. waters. It was another unidentified young right whale found dead about 100 miles east of Nantucket, Massachusetts by NOAA’s vessel Henry B. Bigelow. Preliminary cause of death: severe acute entanglement.
November 15: Transport Canada lifted speed restrictions for the western Gulf of St. Lawrence, and issued three tickets related to them. Additional tickets could result from the 12 currently open cases.
Thanks to Amy Knowlton from The New England Aquarium for the information.