People used to love killing whales. So much killing happened, in fact, that many whale species are nearing extinction. The western South Atlantic humpback whale suffered incredibly at the hands of humans, with the population dipping to just 450 by the 1950s. A new study, however, has found that the species may be bouncing back thanks to conservation efforts to protect whales.
Published Wednesday in Royal Society Open Science, the study found that the current number of humpback whales in this specific population is around 25,000, a dramatic jump from the 1950s low point. The study authors predict that within the next 10 years, the western South Atlantic humpback whale may return to the 27,000-stronghold it was back in 1830 before people began their killing spree.
Back then, people hunted whales for their meat, blubber, and bones. Among the many uses for whales, oil derived from blubber was used for heating, lubrication, soap, and candles. Before the International Whaling Commission placed a moratorium on the practice back in 1982, more than a million whales of various species were wiped out. Some countries still kill whales today. Japan resumed the practice earlier this year despite international outcry. It’s also still legal in Iceland, though the industry opted to skip whaling this season.
Still, the commercial whaling from Japan and Iceland is nothing compared to what these animals have endured historically. The good news is that efforts to protect whales appear to be working in at least some cases. The study authors relied on ship surveys from 2008 and 2012 to gauge the western South Atlantic humpback whale population. The research purposefully doesn’t include an aerial survey from 2005 because it “was probably biased low because it did not account for animals missed by observers on the survey line when the aeroplane surveyed the whale’s habitat at high speeds,” per the study.
The authors suspect that this key omission in data helps explain why their assessment is in their words, more “optimistic” than previous assessments. The model used to create a population estimate includes modern whaling estimates as well as whales struck and killed by whaling vessels. It doesn’t include fishing gear entanglements or other threats to humpback whales not just in the Southern Atlantic but all oceans and could be taking a toll on the population. The study itself admits as much, noting that “not accounting for all sources of anthropogenic mortality in the present assessment probably leads to overestimation of the current status of the population.”
So hooray! These humpback whales are doing well… except they may actually not be doing as well as this study is showing they are. Knowing for sure will require further analysis and, perhaps, more up-to-date surveys.