A Passion for Humpback Whales

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Ari Friedlaender, associate researcher at University of California Santa Cruz, always knew he wanted to be a scientist.

“I grew up in a family of academics near the ocean. In childhood, I spent all my time at the beach, exploring, collecting and counting things and making lists of what I saw.”

He became an ecologist and has visited the Antarctic region every year for the past 20 years to research marine mammal. 2016 was no exception. He and David W. Johnston of Duke University went together to study the movement patterns and foraging behaviours of the largest krill predators - humpback whales. This project was conducted as part of a grant from the Antarctic Wildlife Research Fund (AWR). Their research may provide crucial insight into how climate change could impact the region’s fragile ecosystem.

“Climate changes lead to reductions in the extent and duration of seasonal sea ice cover. These changes impact the demography and ecology of the krill and the predators that rely on krill as their primary prey.”

Friedlaender explains that humpback whales live in open water, and their habitat space is expanding.

“The population of the humpback whales is going absolutely through the roof. They have an opportunity to feed for the longer period of the season and there is almost none or little competition for the resources.”

However, the situation is entirely the opposite for tiny krill.

“Krill require sea ice for their survival. Previous research shows that there is alink between the amount of the sea ice you have in the winter time and how many krill will survive till the next season.” 

Humpback whales need high densities of krill, which are also an important food source for the penguins and the seals. So far, Friedlander and Johnston’s findings show that whales seek areas with the most krill available.

“In summertime whales are spread over the big area, however during the fall this area becomes smaller and smaller. Eventually the whales are concentrated in bays close to shore. The same goes for krill. By the end of the season all the whales and all the krill are in this aggregated area.”

The challenge, however, is that krill fisheries are also attracted to these same areas. A fishery can efficiently scoop up all the krill in an area, practices that are far from sustainable and can negatively impact the whole ecosystem.

“That’s why this kind of research can help fisheries to manage resources properly and operate on a level that doesn’t have a huge impact on the amount of the krill that is available.”

In order to study whales, scientists attach electronic tags to the animals. Depending on the type of tag, scientists can monitor whales from several days to many months. Throughout his career, Friedlaender has helped develop this type of tag technology to better understand the underwater movements and behaviors of marine mammals. In addition to electronic tags, he uses drones to take pictures of whales on the surface.

“We take pictures of the whales on the surface, and can study the length and width and the rate of change when those animals put on the weight. It gives a picture of how they behave at different times of the season and what periods and areas are critical for growth.”

Pictures of whales serve another purpose as well. Friedlaender and his fellow scientists use social media to increase awareness and understanding of the whales, the krill and the ecosystem in the Antarctic Peninsula.