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MERS Humpback Whale Research
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1. Introduction to Humpback Whales 2. Photo Identification 3. Current Threats 4. MERS Entanglement Research |
 BCX0022 ("Houdini") |
 BCZ0004 ("Stripe") |
1. Humpback Whales:
At around 15 metres long and 40 tonnes, humpback whales are one of the largest whales commonly seen in British Columbia. They are easily recognizable by their long flippers (up to 1/3 the length of their entire bodies), their large, black-and-white tail flukes, and the series of bumps on their heads, known as tubercles (see the Cetacean Sightings Network website for further information on recognizing humpback whales).
Most humpback whales spend summers in cool, temperate waters and winters in warmer, tropical waters. The whales' activities vary seasonally; summers are spent feeding, while winter is the time for mating and calving. Female humpback whales only have one calf at a time, and usually only once every two to three years. Calves nurse for about one year, and then are almost never seen with their mothers again. There is little food for humpback whales in warm waters, so after calves are born, humpback whales migrate toward more temperate areas. Temperate waters have higher nutrient and oxygen content, and can therefore support more of the krill and small schooling fish that humpback whales feed on.
Humpback whales in the North Pacific Ocean do not all go to the same places to feed and calve. The SPLASH project, which stands for the Structure of Populations, Levels of Abundance, and Status of Humpbacks, suggests that most of the humpback whales that feed in northern B.C. in summer head to Hawaii in the winter to mate and have their calves, while the humpbacks that spend their summers feeding off southern B.C., Washington, and Oregon are more likely to be found in Mexico in winter.
Because calves only stay with their mothers for about a year, they only have one chance to learn migration routes from summer feeding grounds to winter breeding areas. This means that individual humpback whales are very likely to migrate to the same areas that they were first taken to by their mothers, leading to high "site fidelity," or the tendency for the same individual whales to be seen in the same area year after year.
 The breath or "blow" is one of the easiest ways to spot humpback whales from a distance |
 A humpback whale's head, showing its tubercles |
2. Photo Identification Research:
Humpback whales, like almost every other species of large whale, have been the target of intensive hunting around the world, including off Northern Vancouver Island. Coal Harbour, on the northwestern coast of Vancouver Island, was the site of a whaling station that operated from 1947 to 1967. Whalers from this station targeted the humpback whales around Northern Vancouver Island until this group of whales was completely decimated.
The first records of humpback whales returning to the Northeastern Vancouver Island area after the end of commercial whaling are from the early 1980's (the work of Dr. Alexandra Morton). Humpback whale sightings around Northern Vancouver Island remained infrequent, however, until 2004. MERS researchers, helped by Stubbs Island Whale Watching and other members of the whale watching, research, and Northern Vancouver Island communities, have been documenting the return of the humpback whales to these waters since that time. We have been collecting data to help us understand their population structure, habitat use, and the threats to their population.
Individual humpback whales can be identified by the pattern and shape of the underside of their tails. The tails (also called "flukes") range from being all black to all white, and have unique trailing edges. MERS researchers have created a catalogue of each of the individual humpback whales that has been seen in our study area. We also collaborate with a province-wide catalogue and database maintained by Fisheries and Oceans Canada (DFO), to learn more about humpback whale habitat use and distribution throughout the province. By cataloguing the humpback whales in this way, we can keep track of individual whales over time, and can learn about their movements, calving rates, life expectancies, and more.
 BCY0291 ("KC"), breaching |
 Humpback whale mother "Houdini" (BCX0022) with her calf "Arial" (BCY0767) in 2007. |
 Tail flukes of humpback whales range from being all white to all black. This is the fluke of BCY0057 ("Niagara") |
3. Current Threats To Humpback Whales:
North Pacific humpback whale populations have been expanding since the end of commercial whaling, but these whales are still negatively impacted by anthropogenic (human-caused) threats. Humpback whales in British Columbia are listed as "Threatened" under the Species at Risk Act, and according to the Draft Recovery Strategy for North Pacific humpback whales in Canada, there are three main threats to this population:
1) Ship strikes - In 2006 alone, MERS scientists documented three different humpback whales off Northern Vancouver Island that were hit by boats. One of these whales, a calf born earlier the same year disappeared two weeks after it was first seen with its ship strike injuries, and has not been re-sighted since.
It is very difficult to know how often whales get hit by boats. If the ship strikes are fatal, the whales' bodies often sink, leaving no evidence of the incident. And to make matters more complicated, large ships may not even know that they have struck a whale, as reported in this article describing an incident in the summer of 2010 when a cruise ship in Alaska hit a humpback whale.
2) Entanglement - Humpback whales, along with other cetaceans, can experience injuries and even death by becoming tangled up in fishing gear. This threat, which is likely to be a problem in any area where high densities of whales overlap with intensive fishing effort, is also very poorly understood in British Columbia. B.C.'s coastline is huge and most of it is very remote; this makes it likely that many entanglement events go unseen and unreported.
In our study area alone, we know of multiple humpback whale entanglement events, including one individual, BCY0710 ("Twister"), who became entangled twice in a period of three weeks in 2009. Luckily, MERS researchers, along with Fisheries and Oceans Canada and the Cetus Research and Conservation Society, were able to free "Twister" from the fishing gear both times, and this whale returned to our area in the summer of 2010. He/she had a few scars left over from the entanglements, but seemed to otherwise be healthy.
Not all entangled humpback whales are so lucky, however. Some, like "Nanoose," a whale that was seen entangled in Johnstone Strait in 1994, experience serious injuries and are in very poor health by the time they are sighted and disentangled (click here for more information on "Nanoose"). For other whales, entanglements can result in death before anyone sees, reports, or responds to the incident.
Recognizing the seriousness of this threat to humpback whales, MERS researchers are currently studying the problem of entanglement for humpbacks in British Columbia. Click here for more details.
3) Food shortage and global warming - Through our work, we know that humpback whales in our study area exhibit strong site fidelity (as is the case for humpback whales throughout the northern hemisphere). This means that they visit the same feeding and breeding areas year after year. Finding sufficient quantities of food in their feeding areas is very important, as humpback whales need to eat enough during the summer to sustain them through a winter in warmer waters, where they feed very little, or not at all. Factors like overfishing and changing ocean currents and temperatures can affect the survival and distribution of small fish and krill, the prey that humpback whales rely on, and can therefore lead to local and/or widespread food shortages for humpback whales.
Through collection of prey samples, MERS scientists are contributing to the research on what, exactly, humpback whales in British Columbia are feeding on. We have seen them eat krill, as well as herring, pilchards, and other small fish, but we are not sure of the relative quantities consumed, or how the importance of each prey item changes with location or time of year. This knowledge of the spatial and temporal prey requirements of humpback whales in British Columbia can help ensure the health of their population. For more information about what you can do to help prevent food shortage, entanglement, and ship strikes, along with other threats to humpback whales, see our Conservation page.
 The pink area seen here is a dense swarm of krill, which provides food for whales, birds, and fish |
 The size of an individual krill |
 Humpback whale BCX1187 ("Frosty") lunge-feeding through a school of small fish |
4. MERS Entanglement Research:
One of our current goals as MERS researchers is to learn more about the threat of entanglement to humpback whales in British Columbia. Because many large whale entanglements go unreported, we cannot rely on witnessed entanglement events alone to give us an adequate understanding of how often and where entanglements occur. So, in addition to documenting any entanglements that we do witness, we also look for certain types of scarring and injuries on whales' bodies that entanglements leave behind, and this is starting to give us a more complete picture of the scope of this threat to humpback whales in B.C.
We have been collecting the required photographs and data to study the threat of entanglement to humpback whales in the Johnstone Strait area opportunistically since 2004, and through dedicated research effort since 2010. We are hoping to expand this study in 2011 to include data from other parts of the B.C. coast, both through contributions from whale watchers and researchers in areas like Victoria, and through dedicated fieldwork by MERS researchers in locations that are more remote. Including a wider area in our study will help us to better understand the threat of entanglement to humpback whales throughout British Columbia, providing us with quantitative results to illustrate the need for protection for humpback whales, and a baseline against which any future efforts to reduce this threat can be evaluated.
 BCY0710 ("Twister") became entangled in fishing gear twice in 2009. The orange buoys seen in this photo are part of the fishing gear entangling Twister. |
 A close-up of Twister's head, showing the entanglement |
 After two successful disentanglements, Twister was seen feeding off Northern Vancouver Island in 2010 |
Calambokidis, J., E.A. Falcone, T.J. Quinn, A.M. Burdin, P.J. Clapham, J.K.B. Ford, C.M. Gabriele, R. LeDuc, D. Mattila, L. Rojas-Bracho, J.M. Straley, B.L. Taylor, J. Urban, D. Weller, B.H. Witteveen, M. Yamaguchi, A. Bendlin, D. Camacho, K. Flynn, A. Havron, J. Huggins, and N. Maloney. 2008. SPLASH: Structure of Populations, Levels of Abundance, and Status of Humpback Whales in the North Pacific. Final Report for Contract AB133F-03-RP-00078.
Fisheries and Oceans Canada. 2010 Recovery strategy for the North Pacific humpback whale Megaptera novaeangliae in Canada [DRAFT]. Species at Risk Act Recovery Strategy Series. Fisheries and Oceans Canada, Ottawa. x = 51 pp. Ford, J.K.B., A.L. Rambeau, R.M. Abernethy, M.D. Boogaards, L.M. Nichol, and L.D. Spaven. 2009. An assessment for the potential for recovery of humpback whales off the Pacific coast of Canada. DFO Can. Sci. Advis. Sec. Res. Doc. 2009/015. iv + 33 p.
Rambeau, A.L. 2008. Determining abundance and stock structure for a widespread migratory animal: the case of humpback whales (Megaptera novaeangliae) in British Columbia, Canada. Master's Thesis, The University of British Columbia. 70 pp.
Robbins, J. and D.K. Mattila. 2001. Monitoring entanglements of humpback whales (Megaptera novaeangliae) in the Gulf of Maine on the basis of caudal peduncle scarring. Unpublished Report to the 53rd Scientific Committee Meeting of the International Whaling Commission. Hammersmith, London. Document number SC/53/NAH25.
Robbins, J. and D.K. Mattila. 2004. Estimating humpback whale (Megaptera novaeangliae) entanglement rates on the basis of scar evidence. Report to the National Marine Fisheries Service. Order number 43ENNF030121. 22 pp.
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