China News Service, Beijing, July 8 (Reporter Sun Zifa) Springer Nature's open-access academic journal "Scientific Reports" recently published a marine biology paper, saying that researchers recorded the first record of Antarctic longevity after hunting was restricted in 1976. Baleen whales forage in many ancient feeding grounds, including the first video recording of a large group of fin whales feeding near Elephant Island in Antarctica.
They believe that the recovery and recovery of fin whale populations in Antarctic feeding grounds may restore the nutrition of marine ecosystems and support the recovery of other marine life.
A fin whale feeding on the north shore of Koh Chang (Photo by Sacha Viquerat).
Photo courtesy of Springer Nature
According to the paper, Antarctic fin whales are a subspecies of fin whales (the second largest whale species after blue whales) and live in the southern hemisphere.
In the 19th century, they were overhunted, especially around certain feeding grounds in Antarctica.
By the time fin whale hunting was banned in 1976, more than 700,000 individuals were estimated to have been killed, with no trace around traditional feeding areas.
A fin whale in front of an iceberg on Koh Chang (Dan Beecham).
Photo courtesy of Springer Nature
Corresponding author of the paper, Helena Herr of the University of Hamburg, Germany, in collaboration with colleagues and peers, used helicopter surveys and video recordings to collect fin whales in Antarctica during two expeditions in April 2018 and March 2019. abundance data.
They estimated the fin whale population based on all individuals and groups seen along the 3,251-kilometer search route.
They recorded 100 groups of fin whales, with group sizes ranging from one to four, and eight unusually large groups of up to 150 whales that appeared to be actively feeding.
Previously observed feeding fin whales contained up to 13 individuals.
The authors modeled fin whale population densities in the Antarctic region, predicting a population of about 7,909 fin whales across the survey area, at a density of 0.09 individuals per square kilometer—higher than fin whale populations in other regions, such as Southern California (0.03 head per square kilometer).
They report an apparent fin whale hotspot near Koh Chang, with an estimated 3,618 individuals, or 0.21 per square kilometer.
Aerial photograph of fin whales (Credit: Helena Herr).
Photo courtesy of Springer Nature
The authors conclude that the recovery of fin whale populations could enrich Antarctic marine ecosystems through nutrient cycling through whale feeding and excretion (called the "whale pump"), which in turn supports increased phytoplankton growth and larger krill populations .
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