Whale “Mugging”?

Posted July 27, 2018
Last update: December 30, 2020.

This information is being provided as a result of recent Humpback Whale / boat interactions having received attention in the media.

As much as it is true that Humpbacks can be astoundingly oblivious of boats,  there are some Humpbacks that occasionally  interact with boats. Both cases have the potential for extreme risk to the whales, and to boaters (see www.SeeABlowGoSlow.org).

Why are there interactions like this? And, what are the best practices for boaters / tour operators when this happens?

We strive to document these interactions and which individuals are involved. While we know of a small number of individual Humpbacks who interact with boats, it appears such interactions may be more likely when the whales are socializing with one another. Not surprisingly, these interactions are more likely when the whales are not directed at feeding.

Is habituation a factor? It may be that some Humpbacks have had previous encounters with boats which perpetuates these interactions. For some Grey Whales, it is believed that they have become accustomed to the interactive whale watching practices in Mexico and thereby approach boats when off the coast of British Columbia.

It certainly is a concern that with each boat interaction, the behaviour may be reinforced and that this increases the risk of collision.

But human behaviour is of course also a concern. Many boaters do not know about the increase of Humpbacks we are so fortunate to have off the coast of British Columbia and just how unpredictable this large whale species can be.

Risk of collision is increased if boaters believe that Humpbacks always know where vessels are.

Baleen whales like Humpbacks do not have the biosonar that toothed whales have. They can surface suddenly after long dives, can become highly acrobatic, are often travelling in random patterns, and can be oblivious of boats.

Risk of collision (and habituation) is also increased if the promotion of such interactions leads to increased demand/expectation for close encounters with whales. 

It is a best practices policy of the North Island Marine Mammal Stewardship Association not to promote imagery of whales in close association with vessels. (See the end of this blog for more detail on the NIMMSA Code of Conduct).

The sampling below gives a sense of the human injuries and material damage resulting from collisions. Note that it the law that collisions and entanglements must be reported to DFO (1-800-465-4336) which will allow for better potential to reduce the risks.

Click to enlarge.



How often do the whales die as a result of collision? Dead whales most often sink to the ocean bottom so this is not known.

What to do if Humpbacks choose to interact with a boat, despite all attempts not to put the whales at risk and contribute to their habituation? Put engines in neutral and ideally turn them off and lift them till the whale(s) are beyond 200m and no longer appear to be advancing toward the boat.

In light of the information above, there is then the moral dilemma for boat operators (and media) about whether to promote such interactions and how they are promoted. The NIMMSA guidelines below and the information at www.SeeABlowGoSlow.org may be of use in this regard.

NIMMSA Viewing Guidelines include:

“Keep a distance of at least 200 metres if any whale shows signs of trauma, stress, labour, unfamiliar behavior, habituation towards people or vessels, or the need for extra space.

If a whale approaches a vessel (regionally known as “mugging”) the vessel should turn off their engines and wait for the whale to move outside of 100m. If a vessel captain is aware of another vessel being “mugged” or a whale in the area that is known for mugging vessels, the captain should avoid the area.”

NIMMSA Marketing and Social Media Guidelines: 

“As stewards, it is important NIMMSA members set realistic marine mammal viewing expectations and educate others on best marine mammal viewing practices. To help achieve this NIMMSA members are expected to follow the below marketing and social media guidelines.

  1. Only use images or video in marketing material and on social media that reflects responsible marine mammal viewing in line with this Code of Conduct.
  2. Educate clients on the importance of responsible marine mammal viewing and encourage them to only post images or video to social media that reflect operations in line with this Code of Conduct.”

The North Island Marine Mammal Stewardship’s full code of conduct can be accessed at this link. 

How to Save a Whale (video)

“How to Save a Whale” is an essential resource on the risks of collision and entanglement. It was made possible by the Sitka Foundation. Please see below for the video and share widely.

See this link for our free webinars to share our research and increase understanding of reducing threats to whales.

Click here for information on current, known entanglements off the coast of BC.

With the fortunate increase in the number of Humpback Whales off our coast, it is essential that boaters know more about the risks of collision and entanglement (for the sake of whale AND boater safety).

Our preliminary results, conducted in collaboration with Fisheries and Oceans Canada (DFO), show that ~ 50% of Humpbacks in British Columbia have scarring that shows they have been entangled (>1,000 Humpbacks). This data provides an indication of how very serious the risk of entanglement is. It does not reveal how many Humpbacks have died as a result of entanglement.

Summary of key points on what to do in case you find an entangled whale:

  1. With great urgency, report the entanglement with location. In British Columbia call the DFO Incident Line at  1-800-465-4336. If you do not have cell service, use VHF Channel 16 (Coast Guard). For entanglements in Washington State, call SOS WHALe (1-877-767-9425).  
  2. If at all possible, remain with the whale at a distance until trained help arrives or another boat takes over tracking, otherwise the chances of relocating the whale are greatly diminished.
  3. Take whatever video/photos are possible to document the entanglement and to identify the whale as an individual but maintain a distance that doesn’t stress the whale (minimum of 100 metres). 

Why it is so important NOT to attempt to remove any fishing gear or rope from the whale:

  1. It risks human and whale safety (has led to human death). Professional training and equipment are needed to assess the entanglement and proceed safely with the greatest chance of success.
  2.  Often, much of the fishing gear in which the whale is entangled is not visible at the surface. If members of the public put themselves at risk and remove gear at the surface, they would not help the whale because now it is more difficult to:
    – Recognize that the whale is entangled; and
    – Disentangle the whale even if it is relocated.
    Trailing gear at the surface provides the opportunity for trained responders to attach a tag to track the whale and/or to attach floatation to maintain contact with and slow down an entangled whale. Loss of this gear can significantly reduce rescuers’ ability to save the whale.

For Canada’s Marine Mammal Regulations and key points on how to avoid collision, please see our page www.SeeABlowGoSlow.org.