Canadian team probe sea lion decline
Researchers from the University of British Columbia in Vancouver are investigating the reasons for the decline in numbers of the endangered Steller sea lion, the biggest of all sea lion breeds. A previous hypothesis that overfishing was responsible has already been called into doubt.
The team have been attaching cameras to trained sea lions and analysing how they feed. Sea Lions are renowned for their ability to be taught tricks, and these sea lions have been trained by specialists from the Vancouver Aquarium for fifteen years. "The Steller sea lions are rare in the wild and even rarer in captivity. In order to get into their heads you need access to them 24-hours-a-day and that's what we have here." explains Professor Andrew Trites, team leader and marine mammal specialist from the UBC.
The project has required considerable dedication from the scientists. "It's not been easy. It's taken a lot of time and patience. At times it feels I've been spending more time with them than my family" joked Prof. Trites.
The team's findings reveal that the sea lions find it harder to feed closer to the surface, which may contribute towards explaining the species' decline. Furthermore, a new hypothesis states that the species is in decline because they are not eating the best of diets. Dubbed the 'Junk food hypothesis', the team believe that this has had a dramatic effect on their welfare. "These animals need oily fish such as herring, sand eels and salmon to thrive. But instead they are eating pollock and the animals are full before they get enough calories." explained Prof. Trites.
