The number of large whales entangled in U.S. waters was a little worse than usual in 2017, but entanglements of right whales and in the Northeast were down.

In a report released Thursday, the National Oceanic and Atmospheric Administration confirmed 76 large whales were found entangled in fishing gear or marine debris in U.S. waters in 2017. Six of the 76 entangled whales were found dead, 45 were presumed to be alive but still entangled, four had freed themselves and 21 were freed by good samaritans or members of the national Large Whale Entanglement Response Network.

“Entanglement in fishing gear or marine debris is a very serious conservation and welfare issue,” said Sarah Wilkin, a national stranding and emergency response coordinator and one of the authors of the NOAA Fisheries report. “It can kill or seriously injure large whales. Entanglements that involve threatened or endangered species can have significant population level effects as well.”

Over the last decade, NOAA has confirmed an average of about 70 entanglements a year of humpbacks, grays, minkes, blues and right whales.

The most frequently entangled large whale species in 2017 was the humpback, which accounted for 49 of the 76 entanglements, according to NOAA. That is more than the 10-year annual average, but the humpback’s entanglement numbers can rise or fall by as much as 20 from one year to the next, the data showed. Despite that volatility, the humpback represents 68.1 percent of all confirmed entanglements since 2007.

The humpback has been in the midst of what’s called an unusual mortality event since 2016 because of a spike in strandings along the U.S. East Coast, including three that were entangled in fishing gear. Necropsies performed on about half the stranded whales showed that about half died from human interaction, either due to an entanglement or ship strike.

Four humpbacks have been stranded in Maine since 2016. One humpback whale was found entangled along the Maine coast in 2017, according to federal data.

Right whales accounted for two of the 76 large whales found entangled in 2017, making it the fifth most frequently entangled large whale species last year. The 10-year average for the right whale is 4.6. Despite the lower than usual number, scientists deem even one entanglement a year to be too many for a species that has dwindled down to numbers so low that advocates fear extinction by 2040 unless drastic action is taken.

The National Marine Fisheries Service is now estimating the right whale population has fallen to about 411 whales, down from 451 whales in 2016. Of the whales likely to have survived 2017, about 100 of them are mothers, NFMS estimates. But none of them produced any calves in 2018, which has led regulators to believe the mothers are too tired to reproduce. Longer migrations for food and energy spent towing entangled gear may sap their strength, they fear.

At least 85 percent of right whales have been entangled at least once, according to NOAA Fisheries.

Federal regulators are considering ways to reduce the risk of entanglement with gear, including the vertical lines that connect lobster traps to buoys. Three environmental groups are suing the federal government to force it to take action to protect the right whale from fishing gear entanglement, and have pushed for protections such as seasonal fishing closures and ropeless fishing.

Regulators, whale defenders and fishermen are working on a recovery plan that won’t cripple the lobster industry. They hope to vote on a plan in March.

The Maine lobster industry notes that almost all of 2017 right whale deaths that prompted regulators to consider such drastic action can be traced back to the crab and lobster fishery in Canada, and say it is unfair for regulators to punish Maine’s biggest fishery, which last year was worth about $1.4 billion, when it has already taken steps to reduce right whale entanglements and has not been responsible for any recent right whale deaths.

Most of the 2017 confirmed large whale entanglements happened in Massachusetts, California and Hawaii, according to Thursday’s report. Six whales were found entangled in the waters off Maine, the report showed – five minke whales and the one humpback. Two other minke whales were found entangled outside the Maine waters, but still in the Gulf of Maine. All minke entanglements involved line and pot gear. Four of the whales were reported after they had died.

Penelope Overton can be contacted at 791-6463 or at:

[email protected]

Twitter: PLOvertonPPH

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