Right Whales and Entanglements: More on How NOAA Makes Decisions
Find out more about entanglement risk reduction for large whales and the Take Reduction Plan process.
Right Whales Need More Help
Why is more action needed?
Since June 7, 2017, 30 dead North Atlantic right whales (Eubalaena glacialis) have been observed, 21 in Canada, 9 in the United States. Given the magnitude of these observed deaths, NOAA Fisheries has declared this an Unusual Mortality Event.
In 2017, there were 17 confirmed dead stranded whales (12 in Canada; 5 in the United States) and in 2018, three whales were observed to have stranded in the United States. So far in 2019, nine dead right whales have been documented in Canada, and one in the United States.
Given that there are now only about 95 breeding age females in this small population, we need to make additional effort to further reduce risk of entanglement. Separately, we are reviewing risk from vessel strikes through other NOAA programs. Teams of experts, in both the Northeast and Southeast, are assessing the general recovery and recovery priorities for this species.

Understanding Entanglement Risk
What fishing gear poses the highest risk to right whales?
Any fishing gear that is fixed in the water column poses a risk to right whales, but given the high volume of trap/pot and gillnet fisheries in the waters where right whales feed, calve, and transit, the highest risk comes from these fisheries. This is corroborated by the evidence collected from right whales that have been observed or disentangled.
How do you know this fishing gear poses risks?
We know this gear poses a risk from the data collected from entangled animals, alive and dead.
When a right whale is sighted live and entangled, every effort is made to organize a response team to remove the gear from the whale. In the cases where response efforts are launched, the team retrieves as much of the removed gear as possible. When a whale is reported dead, we also do our best to recover gear and to mobilize scientists who examine the dead animal to determine the cause of death.
Any gear retrieved is brought back to our warehouse and analyzed by gear experts (former fishermen and gear engineers) to determine what kind of gear it is. We also analyze photos of entangled animals to identify gear types that are a risk to these whales.
Identifying which fishery entangling gear comes from can be difficult, because retrieved gear can lose some of the identifying characteristics while its dragged through the ocean and we don’t always have photos that clearly show distinguishing characteristics. Our experts only assign entanglements to a specific gear or fishery when enough evidence exists to do so, which happens very rarely. Evidence can include traps or netting being recovered, buoys that link the gear back to a fishery or individual, line diameter, or markings on the line that indicate a particular fishery. Identifying when, where, and in what fishery the animal was entangled is only possible when gear is marked and/or configured for an area and fishery, and retrieved from an animal sufficiently intact to see those characteristics. In most confirmed entanglements, gear is never recovered. When our experts can’t definitively assign gear to a specific fishery, the entanglement is recorded as having occurred in “unknown gear.”
How did NOAA and the Take Reduction Team assess entanglement risk reduction options?
At the October 2018 Atlantic Large Whale Take Reduction Team meeting, the Team requested that we develop a reference tool that could be used to help them compare the relative effectiveness of different risk reduction measures such as closures, reductions in vertical buoy lines, or using weak ropes. In response to this request, our Northeast Fisheries Science Center worked to develop a modelling tool to help rank the Team's conservation options. This new tool helped team members evaluate just how much risk reduction was likely under various scenarios, based on the likely presence of gear and whales in an area, and how seriously the gear could injure a whale.
The tool uses decades of right whale sighting location data overlaid with what we know about fishing gear distribution and density from Industrial Economic's peer reviewed co-occurrence model used by the Agency since 2013 and Duke University's habitat based whale density model. The concept of this model combining these factors was based on a scientific, peer reviewed, published method for assessing the risk of North Atlantic right whales becoming entangled in pot gear in the Southeastern U.S.
Using a model to look at risk is complicated. There is debate about which poses higher risk—a whale traveling through a high-density field of single traps, or through areas with the less-dense but heavier gear. The former example is typical of coastal Maine. This kind of entanglement could mean the whale keeps swimming with the attached line for possibly thousands of miles. The latter is more typical of offshore lobster fishing using gear that is so heavy it would likely drown a whale relatively quickly should it become entangled. We know both can be lethal, but at the time of the encounter, the heavier gear interaction is considered more severe, because it creates a more immediate risk of death. Therefore, the model also accounts for the variability in the encounter severity.
What is “risk reduction” for a fishery?
Risk reduction refers to changing the fishery in ways that reduce the chances a right whale will become entangled, and the likelihood that an entangled animal will sustain serious injuries or die.
How much risk reduction is necessary?
To recover right whales, the goal is to reduce human-caused deaths to less than 1 animal per year—0.9 to be exact. The average observed deaths and serious injuries caused by entanglements for 2012 through 2016 is 5.15 animals per year, and the estimated annual mortality and serious injury by entanglements is 8.6 animals per year. If we assume that half of the estimated deaths and serious injuries occur incidental to U.S. fisheries (4.3 animals), then mortality and serious injury would have to be reduced by about 80 percent in U.S. fisheries to get below the goal of less than one human-caused right whale death per year.
Where did those numbers come from?
In order to determine the risk reduction needed for U.S. fisheries, we first looked at the minimum average of entanglement deaths and serious injuries from 2012-2016, the most recent years for which these data are available. During this time, an average of 5.15 right whales were killed or seriously injured annually by entanglement in fishing gear.
In about 70 percent of known entanglements, no gear is recovered. Of gear that has been recovered and analyzed, 40 percent of the recovered gear has been attributed to U.S. fisheries and 40 percent to Canadian fisheries. The remainder of the recovered gear was unmarked and could not be identified to a fishery or location.
An entanglement in gear that is not recovered and/or marked, could be from U.S. fisheries, given that right whales spend more of their time in U.S. waters. However, in determining the risk reduction percentage, we assumed the same partition between countries as for entanglements where gear is recovered. Therefore, the U.S. and Canada were each assigned 50 percent of the observed entanglements that could not be assigned to a specific fishery.
Based on this, we then attributed up to 2.5 to 2.6 deaths and serious injuries to U.S. fisheries for each year, 2012-2016. This is more than 2.5 times greater than the goal of 0.9 animals per year. We likely need to reduce death and serious injury by at least 60 percent in U.S. fisheries to achieve the target of less than 1 right whale death per year.
These numbers include only documented deaths and serious injuries. Actual deaths and serious injuries of right whales in U.S. fisheries are likely higher than the observed 2.6 per year. Published research suggests that 40 percent of right whale deaths and serious injuries are unobserved.
Where did the target of less than one human-caused right whale death per year come from?
Every year, we calculate the maximum number of animals that can die in a marine mammal stock by something other than natural causes while still allowing that population to reach its optimal sustainable population number. This is called the potential biological removal level. We calculate this figure for every marine mammal stock that our agency manages, including North Atlantic right whales, as required by the federal Marine Mammal Protection Act.

Right Whales and the Lobster Fishery
U.S. fishermen have already taken so many measures to protect right whales, are whale deaths in Canada to blame for the population decline?
It’s true that whale deaths are also occurring in Canadian waters. Great attention came to this in 2017 when 17 whales were found dead and again in 2019 when 9 whales were found dead in the Gulf of St. Lawrence. The majority of these deaths were linked to Canadian snow crab gear or vessel strikes in Canadian waters. However, right whale deaths and entanglements are still also occurring in U.S. waters as evidenced by the entanglements that have been identified as occurring in U.S. fishing gear. It is also important to remember that estimates suggest that between 20-40% of all deaths are never observed.
By studying the entanglement scars on right whales, scientists have estimated that 85 percent of right whales have been entangled in fishing gear at least once, and that 60 percent have been entangled multiple times.
The sublethal effects of the entanglements right whales escape from are also suspected in playing a role in the declining birth rates of this species. With whales still becoming entangled in U.S. gear, measures must be taken to reduce the impact these interactions have on individual whales, and the population as a whole, if the population is to recover.
Why are you focusing your efforts on just the lobster industry?
There are entanglement risk reduction measures in place for set gillnets and other pot/trap fisheries as well as for lobster. With the right whale population in a rapid decline, we are focusing our efforts at the moment on gear that is known to cause entanglement in the area and fishery with the greatest number of lines in the U.S. Atlantic, the lobster trap/pot fisheries in New England.
We used information from our fisheries to model where vertical lines (i.e., endlines) present an entanglement risk to right whales. About 98 percent of fixed gear endlines along the Atlantic coast (outside of Mid-Atlantic and Southeast bay blue crab fisheries) are fished by the U.S. lobster fishery.
Will saving right whales mean the end of the lobster industry?
No. Saving right whales does not mean the lobster fishery will be shut down. However, we need to work together to ensure that both lobster fishing and right whales are able to survive. The Marine Mammal Protection Act’s Take Reduction Plan and Team process brings together states, fishermen, science, and conservation stakeholders to determine the best ways to minimize impacts to the fishing industry while also reaching our conservation goals. Fishermen play an invaluable role in this process, because their on-the-water knowledge helps guide the Team toward economically and operationally feasible solutions. The Team is tasked with solving some of the most difficult marine mammal-fishery interactions issues—together. Because of the diversity of interests represented on the Team, many of the ideas/solutions are really innovative and demonstrate how important this collaborative effort is.
Where Entanglements and Whales Occur
Do we know where entanglements happen?
Attributing gear from entanglement events to a specific fishery and geographic location is difficult. There are multiple factors that confound identifying discrete locations where entanglements occur. Whales can travel long distances carrying gear, and the moment of entanglement is rarely observed—even more rarely than sighting an entangled whale (compared with the estimated entanglement rates). There are few fishery observers on trap/pot fisheries, particularly state trap/pot fisheries. Entangling gear is not often recovered, and when it is, few identifying characteristics remain.
How can we better understand where they occur?
The Atlantic Large Whale Take Reduction Team has spent many meetings and years grappling with this problem. NOAA Fisheries introduced the concept of gear marking in 1998 under the Atlantic Large Whale Take Reduction Plan. The gear marking strategy is continually updated, most recently in 2015, in hopes of determining where the highest risk of entanglement occurs.
Despite the current gear marking requirements, gear recovered from whales does not usually have these marks. This may mean the whale was entangled in an area where gear marking was not required, that line itself needs to be marked differently for more effective identification, the requirement does not apply in all the right areas, or that people are not marking their gear. Through the Team process, we are exploring ways to refine gear marking to help address these important questions.
These measures provide no immediate relief from entanglement now. We certainly should pursue improvements in gear marking for the future, but we also need to reduce entanglement risks to right whales now in areas where we know whales and gear overlap.
Is it true that there are no right whales in Maine waters?
There are right whales in Maine waters. To get from Massachusetts to Canada these whale travel through the Gulf of Maine. While some may stay entirely offshore, others may hug the coast, as they do through the majority of their East Coast migration. It’s true that there are few records of confirmed right whale sightings in inshore Maine waters, which is expected since there have not been long-term surveys directed at these areas. However, there are several records of opportunistic right whale sightings in coastal Maine waters, and the number of right whales using coastal Maine waters is likely underestimated. With climate change affecting the distribution of right whale prey, researchers suggest that the Western Gulf of Maine may become a more important foraging habitat for right whales in the future.
Why hasn’t anyone been doing regular surveys to search for right whales in the inshore Gulf of Maine waters where lobster gear is most dense?
Our regular sighting surveys are by air and from research vessels. These whales are very hard to spot unless they are in groups and/or at the water’s surface – usually feeding or socializing. The goal of the surveys is to locate and identify as many animals as possible each year. To maximize our success, we focus on times and places where multiple animals are most likely to be present and sightable. Because whales in nearshore Maine waters are likely to be transiting, not aggregating, and not often at the surface, there is a very low probability of sighting them there.
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Has Maine fishing gear ever killed or entangled any right whales?
We have documented Maine lobster gear on three live entangled right whales in 2002, 2003, and 2004. Two of these whales were disentangled (2002, 2003) and one was partially disentangled and remains entangled in some gear today (Kingfisher, 2004). In 2015, a right whale trailing line was seen in offshore Maine waters. The gear was not retrieved and the original entanglement site was not determined.
It is important to draw a distinction between total entanglements and observed entanglements. In 2009 and 2016, we confirmed that two different right whales were entangled in U.S. lobster gear. In two other cases, we confirmed entangling gear to be U.S. trap/pot gear but didn’t have enough information to attribute it to a particular pot/trap fishery such as lobster gear. There were an additional 22 entanglements where the entangling gear and the location could not be identified.
We have not positively identified any gear recovered from a dead right whale as Maine lobster gear. However, the majority of right whale entanglements go unobserved, so there is little we know about entanglements in most geographic areas—not just in Maine. Gear is rarely retrieved from a dead right whale and, when it is, the majority of the gear cannot be attributed to a specific fishery or geographic location. We are trying to improve our gear marking to reduce the high proportion of this unknown or unconfirmed gear for these reasons.
Can’t you tag all the right whales to know where they go?
A satellite tag that stays on long enough and does not compromise the health of these animals does not yet exist. Right whales are highly social with more physical contact between individuals than other large whale species. As a result, satellite tags get rubbed off after only a few weeks. Tags that remain on the animals for a prolonged period of time are invasive: deep shaft bars penetrate through the skin and blubber layer into the muscle layer, leaving the animals exposed to infection. Subjecting an already vulnerable population to these risks is dangerous. However, as new technology is developed, we may be able to test them on some right whales (preferably adult males since females are already at higher risk of human caused injury or death).
We also use a series of underwater microphones to listen for right whale calls. Using bottom-mounted listening devices deployed along the coast, researchers can record whale calls 24/7 and gain new insights into how whales use all habitats.
While these technologies are developed and their use expanded, we continue to rely on sighting right whales to inform stakeholders of where whales are present and extra caution should be exercised. The most recent right whale sighting reports from throughout the region are maintained by NOAA scientists and made available to the public through the online right whale sighting database.
How We Make Decisions: People and Science
Do you work with fishermen before making changes to the fishing regulations?
Yes. We consult with people who will be affected, including fishermen, and a wide range of other experts to help find innovative solutions to entanglement problems through our take reduction process before making a decision. Recommendations from the fishermen are incredibly important in helping us to look at the problem from multiple angles, and find an approach that will have the least impact on industry while still reducing risk to the animals.
The Marine Mammal Protection Act established the take reduction process, which requires teams of stakeholders to help us come up with the best decisions. These teams consist of scientists, state and federal resource managers, fishery representatives, and conservation groups. The Team develops solutions and provides consensus recommendations to NOAA Fisheries. We provide the Team with the best available science and facilitate engaging discussions among team members.
The Atlantic Large Whale Take Reduction Team addresses threats to right whales from commercial fishing. It consists of more than 60 members from up and down the East Coast, including state and federal lobster lobster industry representatives. The team is large to ensure that we have the right people at the table to have the right discussions and raise the right questions.
As you can imagine, getting more than 60 people to agree is very challenging. In April 2019, we had a near-consensus agreement among team members on how to move risk reduction forward. All fishery representatives at the table engaged diligently in these difficult discussions and worked hard to find solutions that nearly all team members found acceptable. At that time, fishery representatives from all New England states recommended that NOAA Fisheries move forward with the measures being considered to date.
Our mandate, under the Marine Mammal Protection Act, is to reduce the risk of death and serious injury due to entanglement. We have a legal obligation to take action, even if the Team can’t agree on specific measures.
Is the scientific information NOAA relies on to make decisions accurate and reliable?
We always use the best scientific information that is available to us. In some cases, the best data still includes uncertainty; however, we are careful to identify what the uncertainties are when presenting any data or publications.
In September 2018, NOAA published North Atlantic Right Whales - Evaluating Their Recovery Challenges in 2018. This technical memorandum summarizes the issues related to the decline in North Atlantic right whales: changes in their distribution, changes in fisheries, changes in prey availability, and the human-caused sources of sublethal impacts, serious injuries, and deaths— particularly ship strikes and entanglements. It also made recommendations about what could be measured to determine if management measures were having a positive effect on the population.
The intent of the technical memorandum was not to explore any one of these issues in detail but rather to identify some examples to illustrate the complexity of environmental and human-caused interactions, and the changes in fisheries over the last decade.
For example, the authors selected the Maine lobster fishery as an example because of its importance in the region. Several other scenarios were also evaluated to look at how they might hypothetically impact the right whale population. We remain committed to continuing open conversations with stakeholders and partners and welcome constructive input, including criticism, so that we can ensure that future actions are based on the best available information at this time on whale biology, risk reduction, and fisheries operations.
We are also currently working to improve the decision tool used by the take reduction team to evaluate the effectiveness of various options for risk reduction. Researchers from the Northeast Fisheries Science Center, the New England Aquarium, the Maine Department of Marine Resources, Duke University, and others are involved. They are looking at ways to better assess changes in whale and endline density, and better assess the metrics used in ranking severity of risk. These efforts will be guided by expert feedback obtained through a peer review, scheduled with the Center for Independent Experts in November, 2019.

NOAA's Commitment to Right Whale Recovery
With only about 400 North Atlantic right whales left, we have an urgent conservation crisis. The United States and Canada must take immediate action to protect this species. We believe that the right steps, people, and knowledge are in place to make decisions that will contribute to right whale recovery and reduce entanglement risk significantly. Our mandate under the Marine Mammal Protection Act has provided the structure, through the take reduction process, to make sure all voices on this issue are heard and that innovation comes from the people who will be most affected by future regulatory action. Under the Endangered Species Act, we are looking at all the threats right whales face and how we can plan for the species’ overall recovery.
What can the public do to help save right whales?
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Stay updated on right whale take reduction and other conservation measures.
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Participate in public meetings. Share your perspectives with Take Reduction Team members who represent your constituency.
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Report right whale sightings to (866) 755-6622 or using the Whale Alert App.
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Keep your distance if you see a right whale. Kayaks, drones, paddleboards, jet-skis, divers/snorkelers, and boats must stay at least 500 yards away.
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Know the facts. There are many misleading statements about entanglements and the measures NOAA is pursuing. For accurate information, statistics, or updates, check your sources or confirm them by visiting our websites for the best available information.
