The world's largest creatures are making a cautious comeback. New research reveals a marked increase in sightings of blue and fin whales in the southeastern Atlantic Ocean, providing encouraging evidence that these magnificent animals are slowly recovering from the devastating impact of 20th century commercial whaling.
Researchers compiled more than 60 years of confirmed sightings from Namibia and South Africa's west coast, including stranded animals. The findings, set to be published in the African Journal of Marine Science, showed that 95 percent of all observations have been recorded since 2012, despite overall numbers remaining low.
"Our results provide important evidence that these giants of the ocean are slowly recovering from the devastating impact of 20th century commercial whaling, which pushed them to the brink of extinction," said study lead author Dr. Bridget James from the University of Cape Town, South Africa. "Sightings remain rare, but they are becoming more frequent than in previous decades – and with sustained protection, there is reason to believe this recovery can continue."
The Legacy of Industrial Whaling
The study focused on Antarctic blue whales and fin whales, both heavily targeted during the industrial whaling era. Between 1913 and 1978, an estimated 350,000 blue whales and 725,000 fin whales were killed, causing dramatic global population declines that brought these species to the edge of extinction.
Today, Antarctic blue whales remain listed as critically endangered on the International Union for the Conservation of Nature's Red List. Their population currently stands at approximately 3 percent of pre-whaling numbers, though scientists report they are increasing slowly at about 5 to 8 percent per year.
Fin whales are currently classified as vulnerable, with populations thought to have recovered to more than 30 percent of historical levels and growing at around 4 to 5 percent annually. Despite these signs of improvement, both species remain difficult to study as they roam vast distances and spend much of their lives in remote Antarctic waters.
Returning to Historic Breeding Grounds
Historic whaling data suggests that the southeast Atlantic may once have been an important nursery area for both blue and fin whales. To address the limited information on their recent presence in the region, researchers compiled verified sightings and strandings recorded between 1964 and March 2025, focusing on the Benguela upwelling ecosystem—a nutrient-rich region off Namibia and the west coast of South Africa.
Blue whales were recorded infrequently, with 12 sightings, one stranding, and five additional published records. Fin whales were encountered more often, with 76 sightings documented along with six stranded whales. Blue whales were most often seen between late spring and autumn, while fin whales appeared to occur year-round.
"As populations slowly rebuild, we would expect to see these whales begin reoccupying parts of their historical range," said study co-author Dr. Simon Elwen from the University of Stellenbosch, South Africa. "The increase in sightings and strandings is consistent with this gradual recovery, although increased offshore observation efforts may also contribute."
Ongoing Threats and Conservation Efforts
Despite more than 40 years since the end of commercial whaling, threats to these ocean giants have not disappeared. Large whales remain at risk from ship strikes, entanglement in fishing gear, and pollution or climate-driven changes in ocean ecosystems.
"Even with more than 50 years of recovery since the end of commercial whaling, we could only compile 12 records of blue whales off our coast," explained Dr. Elwen. The scarcity of sightings underscores both the severity of the population decline and the long road ahead for full recovery.
Nevertheless, the numbers point to the whales' remarkable resilience. The researchers recommend expanding passive acoustic monitoring, increasing trained observer coverage in commercial sectors, and incorporating whale distribution data into marine spatial planning to safeguard their slow but important recovery.
The study offers a rare piece of encouraging news in the conservation world, demonstrating that with sustained protection and international cooperation, even species pushed to the brink of extinction can begin the long journey back from the edge.
