January 29, 2020
Katharine Bear Nalven

What weighs 40 tons, has barnacles all over, and has an album with over 100,000 copies sold in the National Recording Registry? Humpback whales, of course! 

Humpback whale cow and calf pair in Hawaii
Rhianna Thurber

Humpback whales are among the great ocean giants. Commercial whaling pushed humpbacks to the brink of extinction, placing them on the endangered species list in 1970. Fifty years later, the National Marine Fisheries Service (NMFS), the federal agency charged with the management of whales, is proposing critical habitat for three Endangered Species Act (ESA)-listed distinct population segments of humpback whales.

Humpback whales bubble net in Southeast Alaska
Katy Bear Nalven / Defenders of Wildlife

Humpbacks are one of the largest baleen whales and live in every ocean basin in the world. In the summer months, humpbacks are found in high latitude, polar or subpolar regions, feeding on plankton and small schooling fish. In the winter months, humpbacks migrate, sometimes thousands of miles, to their breeding waters in tropical and subtropical waters, and they almost always return to the same breeding waters throughout their lifetime. Humpbacks are extremely vocal animals. In the feeding waters they coordinate bubble netting, a collaborative feeding behavior, with distinctive calls. In the mating season, male humpbacks will sing a lengthy song. The true purpose of the song remains a mystery, but the recordings have become very popular, boosting global awareness of how amazing these animals are. 

Humpback whale 14 DPS
14 Designated Population Segments for humpback whales

Until 2015, NMFS managed the endangered humpbacks as one global population. A 2015 rule established that humpbacks be managed by 14 distinct population segments (DPS). This broad rule removed ten populations from the endangered list and down-listed two populations from endangered to threatened. With this decision, NMFS established that the health of one stock should be considered apart from other stocks. Today, within U.S. jurisdiction, there are three listed DPSs; the Central America, Mexico, and Western North Pacific (DPSs are named by the breeding waters they return to in the winter months). NMFS is now proposing critical habitat for these three ESA-listed DPSs.
When a species is listed today, the managing agency must designate critical habitat to aid in the conservation of that species. That critical habitat mandate did not exist in 1970, so humpbacks have never previously been designated critical habitat. NMFS’s proposal designates an incredibly large area of the U.S. west coast, from Bristol Bay, Alaska to the Canadian Border and from the Southern Canadian border to the Mexico border. NMFS can only designate critical habitat in waters under U.S. jurisdiction. 

Map illustrating the 19 units of Proposed Critical Habitat and the Three ESA Listed Designated Population Segments. From: NMFS Humpback Whale Critical Habitat Proposed Rule; Draft Biological Report 2019
Map illustrating the 19 units of Proposed Critical Habitat and the Three ESA Listed Designated Population Segments. From: NMFS Humpback Whale Critical Habitat Proposed Rule; Draft Biological Report 2019

We are encouraged by this important step by NMFS. However, it is important to remember the intention of critical habitat and what critical habitat does and does not do for humpbacks. Critical habitat is a management tool that arises during agency “consultations,” when efforts are made to determine whether proposed actions will adversely impact a listed species’ critical habitat. Critical habitat does not establish any type of sanctuary, preserve, or closed area, or affect private activities or private lands. 

The biological report is an expansive document written by humpback whale experts in the federal government. The critical habitat review committee reviewed some of the best available science, but we believe some important topics and details are missing. The comment period is open until January 31st, 2020. Join us in telling NMFS to add better detailed information regarding climate change and noise, and tell NMFS to include marine debris and plastic pollution as part of their review! 

Juvenile humpback whale breaching in Southeast Alaska
Cheffy Thomas


In the proposed rule, the only essential habitat feature NMFS determined is prey. This is an important essential feature, but with rapidly changing ocean conditions as a result of climate change, prey and humpbacks are likely to change their locations. Likewise, the types of prey that are available will likely shift as well. Defenders is asking NMFS to better account for prey and humpback movement as a result of climate change. 


NMFS did not include noise  for the humpbacks because the review team felt there is not enough conclusive evidence that noise is degrading  habitat and impeding their survival. This was clearly a point of contention amongst the experts. Other critical habitat designations have included noise, such as for the Cook Inlet beluga and the Hawaiian false killer whale. While it is difficult to determine an exact threshold for noise tolerance, it is no longer appropriate to ignore noise as a permanent habitat feature. Defenders is asking NMFS to revisit this conclusion to include low levels of noise pollution that impede or prevent the whales’ use of the habitat in the critical habitat. 

Adult humpback whale breaching in Southeast Alaska
Cheffy Thomas

Marine Debris

Marine debris is the umbrella term for anything man-made that is polluting the ocean. Whales can ingest or become entangled in marine debris, which can cause serious injury or even death. As much as 12-15 million metric tons of plastic enters the ocean every year. That’s the equivalent weight as over 300,000 humpbacks! NMFS explicitly states that entanglement is a threat for all three DPSs in this critical habitat designation. NMFS also names marine debris, including plastic, as a threat in the most recent stock assessments for humpback whales. We have all seen the pictures of large whales washed up with plastic and other debris in their stomach contents. It is clear that marine debris is degrading the humpbacks’ habitat. Yet, NMFS does not include any review of marine debris in the proposed rule. 

Recovery Plan 

Additionally, the only recovery plan for humpbacks is from 1991. This plan is very outdated considering all the new research about humpbacks and climate change. Additionally, this plan was written 24 years before the decision to manage humpbacks separately by DPSs. In order to be current, NMFS should revise their recovery plan to accurately reflect the Central America, Mexico, and Western North Pacific DPSs. 

Join us: call for NMFS to include marine debris and noise in the habitat designation and create a recovery plan!


Katy Bear Nalven

Katharine Bear Nalven

Representative, Alaska
Katy works to protect Alaskan wildlife as Defenders' Alaska Representative.

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