South Atlantic Humpback Whale Population Rebounds from Near-Extinction

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The news is filled with plenty of sad stories, especially those regarding climate change and the destruction of vital habitats around the globe. Fortunately for us, there are still good things happening in the world, and the whales are one of them. Recent research and updated methods of counting and tracking whale populations has shown an increase in humpback numbers located in the South Atlantic.

Humpback Whale Megaptera novaeangliae. Source: NOAA, public domain.
Humpback Whale (Megaptera novaeangliae). Source: NOAA, public domain.

Tracking South Atlantic Whales 

Whale are notoriously difficult to track because, unless they are at the surface breathing, we can’t see them. With migrations that span thousands of miles, there is much we do not know or understand about the lives of whales. Thus, when populations change, we often don’t know why or how these changes occur, or how many whales there were to begin with.


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Map showing western South Atlantic (WSA) humpback whales (Megaptera novaeangliae) population range in the wintering grounds and areas for allocation of catches in the feeding grounds. Source: Zerbini et al., 2019.
Map showing western South Atlantic (WSA) humpback whales (Megaptera novaeangliae) population range in the wintering grounds and areas for allocation of catches in the feeding grounds. Source: Zerbini et al., 2019.

Recent advances in tracking methods have allowed researchers to better estimate the number of whales that live in the South Atlantic. The population was once thought to be over 27,000 whales, but commercial whaling and other industrial activities dropped the population down to around 450 individuals by the 1950s. Since commercial whaling was banned in 1986, the whale population has been allowed to recover from pre-exploitation rates.

Using historical data, commercial whaling records, and present day information, researchers have continued to put together the puzzle that makes up the complex lives of whales in Earth’s oceans.

Current South Atlantic Humpback Population Research 

Researchers tracking the South Atlantic humpback population have seen a rebound in whale numbers. Using air- and ship-based operations, they put the number of humpbacks in this region at 25,000. Estimates put the total rebound of the whale population at 30% of the pre-commercial whaling numbers as of 2015.

Scientists found that there was a high genetic diversity of the whale populations in the South Atlantic, despite the populations being so low at one time. Researchers are often unable to detect the number of females in a population; additionally, the number of calves that are born but do not grow to adulthood is often unknown due to the fact that we cannot see them at these vulnerable points in their lives.

Although the number of humpback whales has increased globally, the concern for the whales isn’t over. Climate change, marine debris, pollution, and other factors continue to challenge the survival of this amazing species.

The Study

Zerbini, A. N., Adams, G., Best, J., Clapham, P. J., Jackson, J. A., & Punt, A. E. (2019). Assessing the recovery of an Antarctic predator from historical exploitation. Royal Society Open Science, 6(10), 190368. https://doi.org/10.1098/rsos.190368

Hernández-Mares, Pablo. Humpback whales in the South Atlantic have recovered from near-extinction. 18 November 2019. Retrieved from https://www.sciencenews.org/article/humpback-whales-south-atlantic-have-recovered-near-extinction

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