Humpback Whales's Endangered Status Has Been Lifted

Finally, after decades of vigorous effort to conserve them, the population of humpback whales has been increasing steadily, according to recent report.

In the 1950s, there were only a few hundreds of humpbacks. But now, the population count of Western South Atlantic humpbacks has increased by 93%, with an estimated number of 27,000. Dr. Alex Zerbini, one of the authors of the study published in the Royal Society journal Open Science, called the success of this initiative a "positive story."

International Whaling Commission (IWC), the global conservation group for whale, recognizes seven variants of humpbacks found in the southern hemisphere. They are classified according to their distinct genetic traits and migratory behavior.

The Western South Atlantic group bred at the coast of Brazil during winter and traveled to sub-Antarctic and Antarctic regions to indulge in the krills, a crustacean that is similar to shrimp, that are abundant in that area during summer.

At least 300,000 were killed between the 1700s to mid-1900s because of the whaling industry. Zerbini, who has been a marine biology researcher for 25 years, classified the whaling industry into two: "pre-modern" and "modern."

The Pre-modern whaling industry involved hunters jumping on the whale while wielding a harpoon. The modern era, which started in the late 1800s to early 1900s, are using steam-powered boats and explosive harpoons.

In 1904, the whaling industry in South Georgia had bloomed. Since humpbacks often went to nearshore areas and are slow moving as they tend to enjoy coastal waters, they became the primary target. Their fatty body is also highly-sought for, according to Zerbini.

Since then, the population has plummeted dramatically. By the 1920s, humpbacks had gotten so rare that whaling ships could only catch a few dozen per year.

The mass call for conservation started in the 1960s after scientists realized that animals were declining on an unsustainable level. Humpbacks are close to extinction by that time.

Zerbini said that it is unknown when did the whale started to recover as no proper assessment was conducted until the start of the year 2000s when they had seen how well the whales are recovering. But it could be as early as the 1970s, even if illegal whaling was still prevalent around that time,

Although there is still quite some uncertainty about the estimation, the IUCN Red List of Endangered Species already classified the humpbacks as "Least Concern."

However, as the population rises, the concern about its possible impact on the ecosystem dynamics has sprung up.

A group of humpbacks can consume at least a trillion tons of krills each season. Increasing their population might mean intense competition against other krill predators like penguins and fur seals.

Moreover, it has been observed that krills are relocating southward near the pole. For Dr. Jennifer Jackson, a co-author of the study, the feeding ground might not be enough to feed the entire population of humpback, which might affect their survival. It can also mean the whales will have to follow the krills for optimum feeding.