“Trap-Feeding” – a new Humpback feeding strategy

Our research on Humpback Whale trap-feeding has now been published in Marine Mammal Science.

We first documented this novel feeding strategy for two individuals around NE Vancouver Island in 2011. We now know of more than 20 humpback whales who have learned to sometimes use the strategy on smaller, more diffuse schools of juvenile herring. 

Trap-feeding is where some humpbacks set a trap for juvenile herring when the fish are in small, diffuse schools. 

The fish then collect near, or in, the mouth of the humpback to escape predation by diving birds (most often common murres and rhinoceros auklets).

The humpbacks then spin and/ or use their pectoral flippers to push the fish into their mouths. This feeding strategy uses less energy than when humpbacks lunge-feed on greater concentrations of juvenile herring.

Trap-feeding compared to lunge-feeding. Graphic: Uko Gorter.

Humpbacks are also well known for  “bubble-net feeding”. With this strategy, teams of whales work together to coral fish and this includes a member of the team blowing a net of bubbles to stop the fish from escaping.

This is not a strategy employed by humpbacks around northeast Vancouver Island as the current would dissipate the bubbles. It is a used by humpbacks around BC’s central coast and further to the north.  Only occasionally will individual humpback whales around northeast Vancouver Island use bubbles to coral fish (not teams) when there is no current i.e. on slack tide or in a back eddy.

MERS’ research supports that the humpbacks of northeastern Vancouver Island are lunge-feeding specialists on juvenile herring, with some of the whales having learned this new feeding strategy –  “trap-feeding” when the fish are in smaller, less concentrated schools.

To contact MERS for more information about trap-feeding, please email info@mersociety.org. 

Abstract from: McMillan, C. J., Towers, J. R. and Hildering, J. (2018), The innovation and diffusion of “trap‐feeding,” a novel humpback whale foraging strategy. Mar Mam Sci. . doi:10.1111/mms.12557

“The innovation and diffusion of novel foraging strategies within a population can increase the capacity of individuals to respond to shifts in prey abundance and distribution. Since 2011, some humpback whales (Megaptera novaeangliae) off northeastern Vancouver Island (NEVI), Canada, have been documented using a new feeding strategy called “trap‐feeding.” We provide the first description of this foraging innovation and explore the ecological and social variables associated with its diffusion using sightings data, video analysis, and logistic regression modeling. The number of humpback whales confirmed to trap‐feed off NEVI increased from two in 2011 to 16 in 2015. Neither the locations of trap‐feeding sessions nor prey species consumed differed from those documented during lunge‐feeding. However, preliminary results indicate that the schools of fish consumed when individuals trap‐fed were smaller and more diffuse than those consumed when whales lunge‐fed. Top‐ranked models predicting whether an individual would be observed exhibiting trap‐feeding behavior included the following parameters: average number of days per year that the individual was seen off NEVI and proportion of the individual’s associations that were with other trap‐feeders. These results suggest that trap‐feeding may be a culturally transmitted foraging innovation that provides an energetically efficient method of feeding on small, diffuse prey patches.”

Video of trap-feeding where a seal escapes from the Humpback’s mouth.

Whale “Mugging”?

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, 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 is now law that collisions and entanglements must be reported to DFO (1-800-465-4336) which will allow for better potential to reduce the risks.

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 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 viewed at this link. 

Ocular and Slash – ambassadors of the realities of risk

Another whale has recently been documented with scarring from entanglement. We’ve identified the whale as Ocular, born in 2016 to Slash (BCY0177). Slash has her nickname because, from the first time we saw her in 2008, she had extreme scarring from a large boat propellor. Ocular’s entanglement scarring was first documented last week.

Ocular and Slash – ambassadors of the realities of the risk to whales of vessel strike and entanglement.

They are not exceptional cases. Our research, done in collaboration with DFO, shows that ~1 in 2 Humpback Whales off BC’s coast have scarring from entanglement. This data provides an indication of how serious the risk of entanglement is but does not reveal how many Humpbacks die after becoming entangled.

How many are hit by boats? We don’t know. We see scarring on some survivors but here too, it is not possible to know how many are hit and die as a result of their injuries. There are whales like KC (BCY0291) that we know have been both hit by a boat and been entangled (twice that we know of in KC’s case).

Thankfully, with the new Marine Mammal Regulations it is now law that such interactions with marine mammals must be reported (all incidents of concern to 1-800-465-4336). But increased public awareness is also very much needed. Please see www.HowToSaveAWhale.org.

Content about what to do if you find an entangled whale is summarized below:

  • With great urgency, report the entanglement with location to the DFO Incident Line / VHF 16. 1-800-465-4336.
  • Do NOT attempt to remove any fishing gear or rope from the whale as it risks human and whale safety (has led to human death).
  • 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
  • Take whatever video/photos are possible but maintain a distance that doesn’t stress the whale.

Professional training and equipment are needed to assess the entanglement and proceed safely with the greatest chance of success. Often, much of the fishing gear in which the whale is entangled is not visible at the surface. If well-intentioned members of the public remove the gear at the surface, it is made much more difficult to:
1. recognize that the whale is entangled and;
2. 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.

July 8th documentation of Ocular’s entanglement injury near Comox by Peter Hamilton, Lifeforce Foundation.

Three Generations of Humpbacks Documented!

Three generations of Humpback Whales have now been documented!

This is such an indication of the great collaborative effort in studying the fortunate return of Humpback Whales off British Columbia’s coast, and its importance.
Alethea Leddy was the first to document Apollo with a calf, now nicknamed Nova. Alethea’s photos from June 18th near Race Rocks even allowed us to determine that the calf is male. The calf had been lying on his back tail-lobbing whereby the pelvic area could be seen. See Aletha’s photo at the end of this blog that allowed determination of Nova’s gender. For detail on gender determination in Humpbacks, click here for our blog on the subject. 

We know that Apollo was born in 2010 to Horizon but did not know her gender before now.

We first documented Horizon in 2004 when she was already at least subadult. Apollo is her first known calf. We documented a second calf in 2013 and have not had re-sightings of this whale.

Calves only stay with their mothers for a year. Having these solid ID photos allows us to ID them in future. Because the calves often lose a lot of the white pigmentation in their tails as they age, It is particularly helpful to also have photos showing both sides of the dorsal fin and the trailing edge of the tail. Being able to study whales as individuals allows us to have data informing everything from age of first calving (varies per population), to life expectancy, to social associations, to how the whales use the coast.

The nicknames:
Humpbacks are nicknamed for distinctive features so that it is easier to recognize them as individuals. Horizon has horizontal lines on her tail. The markings on Apollo’s tail suggest planets. And, while some of the white will likely disappear on the calf’s tail, there is a distinctive line and a moon-shaped bump that will likely stay. Thereby, Alethea suggested Nova, also keeping with the celestial theme of these 3 generations of whales.

To make the point again that it takes a dedicated community to study giants, below are the names of all those who have contributed sightings of these 3 whales (outside of our direct MERS team). This includes naturalists, captains and guest of at least 9 ecotourism companies as well as our research colleagues:
Jarret Morton, Alexandra Morton, Marilia Olio, Tasli Shaw, Mark Malleson, Gary Sutton, Jos Krynen, Amber Stroeder, Kaitlin Paquette, Johanna Ferrie, Eiko Jones, Peter Hamilton, Leif Nordman, Shea Majbroda, Michelle Mercer, Chloé Warren, Jennie Leaver, Jeff Aoki, Carmen Pen, Alison Ogilvie, Geoff Dunstan, Roger McDonell, Franz Plangger, April Macleod, Jim Borrowman, Jess Fargher, Maureen Towers, Dave Towers, Sophia Merritt, Kyle Kermode, Inge van der Wulp, Shea Majbroda, Jan Kees, Humpbacks of the Salish Sea, Keta Coastal Conservation.

For detail on gender determination in Humpbacks, click here for our blog on this subject.

See this link to purchase a MERS Humpback Whale Catalogue (PDF) for whales documented from the northern Strait of Georgia to the northern end of Goletas Channel. Updated PDF provided annually at no extra charge. 

We’re Hiring! MERS Data Analyst

Job Posting
Marine Education and Research Society
Summer Student Position: Data Analyst  

The Marine Education and Research Society (MERS) is a non-profit organization dedicated to promoting conservation and understanding of marine ecosystems through scientific research, environmental education, and marine wildlife response.  We are based on NE Vancouver Island. For information about MERS’ research, education and wildlife response efforts, see www.mersociety.org.

The Data Analyst will be involved in MERS’ efforts to study and protect marine mammals in British Columbia, with a focus on consolidating Humpback Whale sighting and photo-identification data as part of a province-wide project to better understand this population. This Humpback Whale study is a collaborative, coast-wide effort that will allow for enhanced knowledge of the abundance, habitat use, social associations, movements, and threats of Humpbacks in B.C., for the purposes of conservation.

Duties will include:

  1. Conducting comparative analysis of Humpback Whale catalogues to determine the identifications of individual whales.
  2. Data entry and database management for Humpback Whale sighting and photographic data.
  3. Assisting in supervising volunteers during data entry and photographic data analysis in order to maintain the quality of the MERS databases.
  4. Aiding in MERS’ work to serve as a resource to media and the local community (with a focus on local ecotourism operators) in order to enhance the economics/value of wildlife viewing experiences.
  5. Helping to develop resources to reduce threats to whales and, thereby, increase the sustainability of ecotourism in the region.
  6. Other office-based work as needed.This is an office-based position but there may also be some opportunities for the Data Analyst to accompany MERS researchers on boat-based surveys to collect Humpback Whale photo-identification data.

Successful candidates:

  • Are Canadian or have a Canadian work permit. (Please note: MERS will not be able to assist candidates in obtaining a Canadian work permit).
  • Are students currently enrolled in a full-time post-secondary program, returning to school in the fall of 2018 (funding requirement).
  • Are studying biology, environmental science, resource management or a related field and have knowledge of the biology and ecology of marine mammals in British Columbia.
  • Are between 15-30 years of age (funding requirement).
  • Have strong computer skills. Previous experience with some or all of the following programs an asset: Microsoft Excel, Photo Mechanic, Filemaker, Adobe Lightroom, and QGIS.
  • Work well independently and with minimal supervision.
  • Have experience with data entry.
  • Have exceptional organizational skills.
  • Are able to demonstrate strong abilities in matching whale flukes and fins for identification.


Work term:
10-week contract with an anticipated start date of June 18th, 2018

Position location:
Much of the work can be done remotely but, for the purposes of supervision, it is preferred that the Data Analyst is based in Victoria or on NE Vancouver Island.

Application deadline:
May 13, 2018

Application format:
Applications should include a cover letter specifically addressing position requirements, resume, and 3 references (name, position and email address) with a minimum of 2 being employment contacts.   Applications should be emailed to nicole@mersociety.org.

Selection procedure: 

  1. References of short-listed candidates contacted.
  2. Short-listed candidates interviewed via SKYPE.
  3. Final interviews held in person in Vancouver, Victoria or Port McNeill. Candidates will be asked to complete an exercise to assess their ability to match whales IDs.

Please note that only short-listed applicants will be contacted and that this would happen before May 20th.

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.

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 over 47% 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.

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

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).
  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 but maintain a distance that doesn’t stress the whale.

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.