Humpback WhalesAt 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 usually never seen with their mothers again. There is little food for Humpback Whales in warm waters, so after calves are born, Humpback Whales migrate back toward more temperate areas, like the waters off British Columbia. 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 (acronym 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, 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 the 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. | A Humpback Whale pectoral fin. |
MERS Photo Identification ResearchHumpback 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 intensely targeted the Humpback Whales around Northern Vancouver Island until 1964 when whaling this species was banned. 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 and by shape of their dorsal fins. The tails (also called "flukes") range from being all black to all white, and have unique trailing edges. MERS researchers have created and maintain a catalogue of individual Humpback Whales that have been seen in our study area. We also collaborate with colleagues to update Fisheries and Oceans Canada’s province-wide catalogue (maintained to 2010) 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. | Humpback Whale mother "Houdini" (BCX0022) with her 2007 calf "Arial" (BCY0767). Humpback Whales tail flukes vary greatly in shape, markings and how much black or white there is, . This is the fluke of “Niagara” (BCY0057). We assign nicknames for distinctive features like the waterfall like pattern on Niagara’s tail. |
MERS Research into Threats to Humpback WhalesNorth 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 "Of Special Concern" under the Species at Risk Act, and according to the Recovery Strategy for North Pacific Humpback Whales in Canada , three major threats to this population include entanglement in fishing gear, vessel strikes, and potential prey shortage. 1) Entanglement in fishing gear - 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 currently 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. Off northern Vancouver Island alone, we have witnessed multiple Humpback Whale entanglements, including one individual, BCY0710 ("Twister"), who became entangled twice in a period of three weeks in 2009. Luckily, trained responders from Fisheries and Oceans Canada (DFO), MERS, and the Cetus Research and Conservation Society were able to free Twister from the fishing gear both times, and this whale has returned to our area every summer since. Not all entangled Humpback Whales are so lucky, however. A whale we knew well, "Canuck", was seen entangled in the Strait of Georgia in 2011 but trained responders were unable to free this whale from fishing gear because somehow the fishing line that was at the surface had been removed and Canuck’s health deteriorated. For other whales, entanglements can result in death before anyone sees, reports, or responds to the incident. A large part of our education effort is to educate about what to do and what NOT to do in case of witnessing a whale entanglement. Please see our “How to Save a Whale” resource. This includes an explanation about why the gear at the surface is essential in a rescue operation and also, emphasizes the great importance of reporting entanglements as soon as possible to 1-800-465-4336. Recognizing the seriousness of this threat to Humpback Whales, we are studying the problem of entanglement for Humpbacks in British Columbia. In addition to documenting any entanglements that we witness, we also look for certain types of scarring and injuries on whales' bodies that entanglements leave behind, Our preliminary results conducted in collaboration with DFO show ~50% of Humpbacks in British Columbia have scarring that shows they have been entangled. 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. |
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. |
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The parallel cuts seen here on the back of “Slash” (BCY0177) in 2006 indicate a recent ship strike. Remarkably, she survived the incident, and has had several calves since. | Houdini's 2006 calf, was hit by a boat in the summer of that year. Not long after this photo was taken, the calf disappeared, and has not been re-sighted since. Photo credit: Chantelle Tucker. | “KC” (BCY0291) has been known to us since he arrived with Houdini as a calf in 2002. He was hit by a boat in 2013 causing the distinctive scarring on his dorsal fin. He has also been entangled at least twice. |
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The pink area seen here is a dense swarm of krill, which provides food for whales, birds, and fish. | A dense school of herring. These schools, known locally as "bait balls" provide much of the energy that Humpback Whales off northeastern Vancouver Island require. | Humpback Whale BCX1187 ("Frosty") lunge-feeding through a school of small fish. |
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