Marine Mammal Commission

North Atlantic Right Whale

The North Atlantic right whale is one the world’s most endangered species of large whale. It was hunted to the brink of extinction by commercial whalers by the early 1900s. North Atlantic right whales now occur almost exclusively along the east coasts of the United States and Canada where their primary causes of mortality and injury are entanglement in fishing gear and strikes by vessels. The North Atlantic right whale is one of three right whale species, which also include the North Pacific right whale and the southern right whale.

Right whale off Florida coast

Right whales off Florida coast. (New England Aquarium)

Species Status

North Atlantic right whales were first hunted as early as the 9th century by Norse whalers. When substantial catches of right whales by commercial whalers ended in the Atlantic in the early 1900s, the population off Europe had apparently been extirpated and a small population of perhaps a hundred or fewer whales survived in the western North Atlantic off the United States and Canada. After 1935, when an international agreement went into effect banning the hunting of all right whales, their numbers began to increase slowly in the western North Atlantic. Recovery, however, has been impeded by mortality and serious injury from ship strikes and entanglement in fishing gear. During the 1990s, the number of right whales may have declined due to those causes, but since 2000, the number has increased slowly due to a sudden increase in births. The current size of the population is estimated at about 500 whales. Only the North Pacific right whale for which there is no reliable estimate of population size, may be as small or smaller. Nearly half of all North Atlantic right whale deaths documented since 1970 have been due to ship strikes and entanglements in fishing gear.

A recovery plan for the species was adopted in 1991 and updated in 2005. In 1994, three areas were designated as critical habitat. In January 2016, however, those areas were expanded and consolidated into two large areas, one covering waters off the Northeast in the Gulf of Maine from the U.S.-Canada border to eastern Massachusetts, and the other area along the Southeast U.S. coast from southern North Carolina to central Florida (see NOAA Fisheries website for critical habitat maps). Whereas management measures to reduce ship speeds and change routes beginning in 2007 and 2008 appear to have reduced ship strike-related deaths, management actions since the late 1990s have failed to reduce entanglement-related deaths. Entanglement is now the most significant cause of right whale mortality.

Number of observed North Atlantic right whale carcasses and their causes of death from 1970 through October 2016. (Perinatal deaths are calves that die during the first months of life for reasons that are usually unknown.)

Although no dead right whales were found in U.S. waters in 2015, three carcasses were found between late June and mid-July 2015 in the southwestern Gulf of St. Lawrence, Canada. The first was towed ashore for necropsy, while the other two were reported drifting offshore. One of the latter carcasses is believed to have been an animal that washed ashore in an advanced state of decomposition on the Magdalen Islands in August. No cause of death could be determined for any of the three whales. There were also more than a dozen new cases of live whales observed in a compromised condition or newly entangled. Two were calves with propeller wounds and a third was a juvenile with injuries that might have been due to a ship strike. Also five whales were found entangled in fishing gear, only one of which could be disentangled, and five others were seen with severe new entanglement wounds but did not appear to be carrying any gear.

More Information

Ship Strikes and Right Whales

Right Whales and Entanglement in Fishing Gear

Right Whale Listening Network, The Cornell Lab of Ornithology

What the Commission Is Doing

The Marine Mammal Commission is continuing to monitor right whale deaths and injuries caused by ship strikes and making efforts to minimize their occurrence. No ship strike deaths were documented in 2014 and the lack of such deaths since 2008 in or near vessel speed zones that were established that year by the National Marine Fisheries Service (NMFS) to reduce collisions with right whales by large vessels suggests the rules have been effective. In March 2014, the Commission recommended denial of a petition by the American Pilots Association requesting that dredged channels be exempted from speed restrictions in management areas. In 2014, we met with NMFS staff to review the status of the petition and also reviewed its status at our Annual Meeting in May 2015. A decision on the petition had not been made by NMFS as of July 2015.

The Commission continues to devote attention to the goal of reducing right whale deaths due to entanglement in fishing gear. Commission staff participated in meetings of the Atlantic Large Whale Take Reduction Team in 2014 and early 2015 and continued to comment on rules proposed by NMFS to reduce right whale entanglement risks under an Atlantic Large Whale Take Reduction Plan. In late June 2014, NMFS adopted a final rule to prevent entanglement of whales in trap and gillnet buoy lines (also called “endlines”). The rule seeks to increase the number of traps per buoy to reduce overall endline numbers and thereby decrease entanglement risk. In September 2013, the Commission commented that the proposed action was inadequate and recommended additional measures, including additional time-area fishing closures and requirements for fishermen to record the number and location of endlines fished. Protection measures in the final rule were weakened compared to the agency’s initial proposal and our recommendations were not adopted.

In August 2014, the State of Massachusetts requested an amendment to the new rule to shorten a seasonal closure in the Cape Cod Bay region. To account for reduced right whale protection, the state proposed expanding the size of the regulated area. The Commission commented in support of the proposed amendment in November, and in December, NMFS adopted a final rule approving the requested change. In 2015, additional exemptions from the June 2014 rule were requested by the States of Maine, Massachusetts and Rhode Island. Those requests sought to exempt various state waters from requirements and were estimated to reduce effectiveness of the new take reduction plan measures by nearly 25 percent. No alternative measures to compensate for the reduced protection were offered. In April 2015, the Commission therefore commented in opposition to the changes unless and until additional protection measures were identified In June 2015, NMFS adopted the exemptions with additional gear marking requirements, but no measures to compensate for reduced protection.

Commission Reports and Publications

Laist, David W., Knowlton, Amy R., and Pendleton, Daniel. 2014. Effectiveness of mandatory vessel speed limits for protecting North Atlantic right whales.

Laist, David W., Knowlton, Amy R., Mead, James G., Collet, Anne S., and Podesta, Michela. 2001. Collisions Between Ships and Whales.

Reports prepared for the Marine Mammal Commission:

Lowry, Lloyd, Laist, David W., and Taylor, Elizabeth. 2007. Collisions Between Ships and Whales.

Weber, Michael L. and Laist, David W. 2007. The Status of Protection Programs for Endangered, Threatened, and Depleted Marine Mammals in U.S. Waters.

Reeves, Randall R., Read, Andrew J., Lowry, Lloyd, Katona, Steven K., and Boness, Daryl J. 2007. Report of the North Atlantic Right Whale Program Review.

Commission Letters

Letter Date Letter Description
April 13, 2016

Letter to U.S. Coast Guard on Atlantic Coast Port Access Route Study Final Report

April 21, 2015

Letter to NMFS on proposed modification of critical habitat for North Atlantic right whales

April 20, 2015

Letter to NMFS on proposed exemption of various state waters from the Atlantic Large Whale Take Reduction Plan and establishment of new gear marking requirements

November 21, 2014

Letter to NMFS on proposal to delay the start date for the Massachusetts Restricted Area under the Atlantic Large Whale Take Reduction Plan

March 4, 2014

Letter to NMFS on a petition to exempt dredged channels from vessel speed restrictions

September 13, 2013

Letter to NMFS on proposed rule to reduce right whale entanglement in commercial trap/pot and gillnet fishing gear

August 5, 2013

Letter to NMFS on proposed rule to delete the expiration date for regulations limiting vessel speeds

April 20, 2012

Letter to NMFS on report evaluating the effectiveness of the final rule to implement vessel speed restrictions to reduce the threat of vessel collisions

Learn More


The primary causes of mortality and injury to right whales are entanglement in fishing gear and strikes by vessels. Other potential threats include spills of hazardous substances from ships or other sources, and noise from ships and industrial activities.

Current Conservation Efforts

NMFS and the Coast Guard have taken both regulatory and non-regulatory steps to reduce the threat of ship strikes, including mandatory vessel speed restrictions in Seasonal Management Areas, modification of international shipping lanes, enforcement, and public outreach. Learn more about the measures and rulemakings implemented to reduce ship strikes.

To address entanglement in fishing gear, NMFS established the Atlantic Large Whale Take Reduction Team. This team has been unable to agree on all measures needed to meet take reduction goals and the NMFS has therefore developed a plan it believes will be necessary to reduce the incidental serious injury and mortality of right whales, as well as other whales. Additionally, a recovery plan for the species was adopted in 1991 and updated in 2005.

Additional Resources

NMFS 2014 North Atlantic Right Whale Stock Assessment Report

NMFS 2005 Recovery Plan for the North Atlantic Right Whale

NOAA – On the Trail of the Northern Atlantic Right Whale

NMFS – Protected Resources: Key Protection Measures for the North Atlantic Right Whale

NMFS – Protected Species Branch: North Atlantic Right Whale

NOAA – Greater Atlantic Region: Atlantic Large Whale Take Reduction Plan

Alaska Sea Life Center: Satellite Tracking of North Atlantic Right Whales

North Atlantic Right Whale Consortium