In recent months, along the East Coast of the United States, humpback whales have been experiencing what’s known as an Unusual Mortality Event, with an elevated number of strandings being reported since 2016. While necropsies are still being performed, initial results from the Marine Mammal Stranding Center indicated that at least 2 whales of the recent strandings have died as a result of ship strike. However it is known that 40% of necropsies carried out after an Unusual Mortality event show entanglement and ship strike as the leading causes of death for whales.
Underlying these threats is climate change. Ocean warming is changing the distribution of key prey species, with whale distributions shifting as they track prey, and bringing whales into greater contact with fishing gear and shipping routes.
These recent strandings have highlighted the critical need for practical solutions and policy actions. Science is unequivocal on the value of vessel speed restrictions in reducing deaths of large whale species and sea turtles from vessel collisions, and a 10-knot speed limit for all vessels would significantly reduce lethal ship strikes. Rope-less fishing systems have the ability to virtually eliminate the risk of entanglement for whales, while meeting the fisherfolk’s needs. Additionally with the push for clean energy sources, there is a need for strong federal mitigation and monitoring requirements that protect whales and other wildlife while responsibly developing offshore wind.
With several whale species listed as endangered or critically endangered, the wide-spread adoption and enforcement of vessel speed reductions, rope-less fishing gear and the responsible development of offshore wind is crucial for the protection of the declining whale populations.
Source: Natural Resource Defence Council – Expert blog – January 23rd
More resources and guidance on entanglement, vessel strike and marine mammal stranding can be found in the entanglement, collision/strike and strandings factsheets of the Marine Mammal Management Toolkit