The rebound in the population of humpback whales after their near extinction brings hope to marine scientists.
July is the month for humpback whales to travel 600 miles from the north to Queensland, Australia's warmer waters, where they mate and give birth.
"We think we have more whales in the population than we did pre-whaling," professor Mike Noad, director of the Centre for Marine Science at the University of Queensland, told ABC News.
A total of 40,000 humpbacks are expected to pass through Eastern Australia this season.
The Organization for the Rescue and Research of Cetaceans (ORRCA) conducted a citizen science migration census last week and recorded 5,116 humpbacks, which is a 57 percent increase.
Nursing Humpback
In a rare opportunity, scientists captured a whale calf breaking away from its mother and leaving a trail of milk in the Pacific Ocean off the coast of Colombia.
In the said video, a 900-kilogram calf is seen rising to the surface in the Gulf of Cupica.
The Macuaticos Foundation, the team that took the footage, uses non-invasive sensors, including a camera, GPS, and a device that was attached to the calf's back, to capture the sounds made by the whales.
Biologist Natalia Botero, one of the scientists behind the video, said the footage will significantly help the scientific understanding and conservation efforts of humpback whales, as reported by Phys.Org.
"By learning more about their behavior... we can promote appropriate conservation actions," she added.
Despite efforts by researchers in the past years to have lactation recordings of humpback whales, these inmate moments are considered elusive, marking this as the third time such a feeding event has been documented.
The whales stayed in the waters off Colombia from July to November.
Humpback whales, giant cetaceans that can grow up to 17 meters (55 feet) long, weigh about 40 tons, and travel some 8,500 kilometers (5,280 miles) every breeding season, were declared endangered in 1973 after their population crashed in 1961.
But due to efforts to conserve them, they were removed from Australia's threatened species list last year. The International Union for Conservation and Nature also announced that the humpback population is rising.
"It hasn't required much. Just stopping killing them was enough," Noad said. "They recovered nicely under their own steam, which is very pleasing."
Read Also: Two Humpback Whales Caught In Shark Nets Off The Queensland Coast During A Whale Migration
Climate Change
Marine scientists hope the population of Australian humpbacks will stabilize, but some express worries that they may have reached their carrying capacity.
Noad said climate change has an impact on krill populations in the Antarctic, where the whales go to eat in the summer.
"What happens then is the whales start getting thinner because there's not enough food, and then they stop reproducing," he added.
He also claimed that the decrease in the number of krill is devastating for the Antarctic ecosystem, noting that in the region, everything either eats krill or eats something that eats krill.
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