How long do they live? Humpback whales can live up to 95 years  that we know of, and this may be an underestimate since longevity studies are not an easy task.
Where are they found? You can find these giants in any major ocean. See Figure 1.
What do they eat? Like other whales with baleen plates instead of teeth, they filter in small fish and krill .
What do they look like? They’re not as large as the Blue and Fin whales, but they can still reach an impressive 60 feet in length and weigh up to 44 tons. One of the largest Humpback whales ever recorded was 89 feet long (I wonder how old he was?) . They also love to jump out of the water, which would just be spectacular to see…From a distance.
How do they reproduce? Humpback whales reproduce through typical sexual reproduction and females give live birth to a calf about once every 2 to 3 years . They reach sexual maturity as early as 5 years old and it looks like baleen whales in general do not show signs of reproductive senescence , which is just one more reason there needs to be more studies on longevity in these species.
How do scientists know how old they are? They don’t really know since age estimation techniques are usually lacking, plus it doesn’t help that Humpback whales show no physical signs of aging. Most scientists estimate age based on the accumulation of waxy ear plugs and baleen plate thickness, but as you can imagine, that’s not very useful strategies if you want to know the age of a living whale. Plus, neither technique is very accurate. To estimate the age of live whales, mark and watch techniques can be used, but the birth date of the whale is needed. Some researchers are now switching to epigenetic analysis of skin samplings and lipid profile analysis for age estimations .
So what are we lacking? Well, we need information regarding reproductive senescence in this species. I couldn’t track down the nuclear genome of Megaptera novaeangliae on NCBI, but they do have mitochondrial genome information available.
Conservation status: The Humpback whale is listed as least concern on the IUCN Red List. They were once almost hunted to extinction. It is now illegal to hunt Humpback whales and well, look at them! Who would want to kill such a beautiful creature?
Please feel free to contact me if you would like to contribute your wisdom of these long-lived beauties.
- Macdonald, David, ed. The encyclopedia of mammals. OUP Oxford, 2009.
- Whale facts.org. Humpback Whale http://www.whalefacts.org/humpback-whale-facts/ Accessed 10/10/2016
- Fisheries and Oceans Canada. 2013. Recovery Strategy for the North Pacific Humpback Whale (Megaptera novaeangliae) in Canada. Species at Risk Act Recovery Strategy Series. Fisheries and Oceans Canada, Ottawa. x + 67 pp.
- Polanowski, Andrea M., et al. “Epigenetic estimation of age in humpback whales.” Molecular ecology resources 14.5 (2014): 976-987.