Entangled Marine Mammals

Air Guns Threaten Right Whale Extinction

In June 2017, NOAA Fisheries published proposed whale protections for the surveys. By winter the division’s biologists saw a problem: The protections for the North Atlantic right whale were too weak and put airguns in their direct path.

The agency had proposed a seasonal ban on using airguns up to 47 kilometers (about 29 miles) from shore between November and April, when the whales were known to migrate and give birth along the mid- and south-Atlantic coast.

But peer-reviewed research led by a NOAA Fisheries analyst concluded the whales were traveling farther from shore than ever before — and directly into the path of the proposed survey activity. A draft report for the Navy reached a similar conclusion.

Warming Oceans Increasing Whale Entanglements

“With the ocean warming, we saw a shift in the ecosystem and in the feeding behavior of humpback whales that led to a greater overlap between whales and crab fishing gear,” said Jarrod Santora, a researcher in applied mathematics at UCSC’s Baskin School of Engineering and first author of the study, published January 27 in Nature Communications.

Less than 500 North Atlantic Right Whales Remain

Last year saw an alarming dieoff of North Atlantic right whales, something researchers refer as an “unusual mortality event.” Their carcasses littered the shores of the east coast—12 in Canada and 5 in the United States. Necropsies revealed that most of the animals died from blunt force trauma or entanglement issues. This brings the North Atlantic right whale’s fragile population to an estimated fewer than 500.

‘Vaquitas will be extinct in a few years’

“The situation is completely out of control,” says Lorenzo Rojas-Bracho, a cetacean expert at the National Institute of Ecology and Climate Change in Ensenada, Mexico, and member of the International Committee for the Recovery of the Vaquita, an international advisory group to the Mexican government. “Of course, there’s a risk in capturing the vaquitas. But it’s clear now that they will be killed [in gillnets] anyway.”