Despite their names, sea lions are basically the dogs of the sea. Playful, smart, and surprisingly loyal, they are definitely some of the most endearing sea creatures. Even better, sea lion offspring are called pups; how adorable, right? Well, we’re about to go dark, as I’m going to talk about how sea lion mothers eating “junk food” starves pups.
Emaciated sea lion pups
An increasingly worrisome number of sea lion pups have been showing up starving and emaciated on California beaches. While their situation has been getting worse and worse, it’s only last year that the sea mammals have reached a new low.
As many as 3,000 sea lion pups have shown up dead and dying of hunger on various beaches in California between January and June of 2015. By the end of the year, as many as 4,200 animals have been taken to a nearby marine mammal center, the largest number seen by such centers in 40 years.
Mothers eating junk food
While scientists have been trying to figure out the reason behind it, they have only in a recent study managed to come up with a plausible theory. The study published in the Royal Society Open Science journal on the 2nd of March offers some interesting insight on the matter.
The study claims that the sea lion pups are dying because of their mothers’ bad eating habits. According to Discovery News, sea lion mothers have been eating increasingly bad food, with the study dubbing the equivalent of us eating junk food. But what do experts consider to be the fast food of sea mammals?
Instead of eating the usual rich in nutrients and calories anchovies and sardines, sea lions are now eating more and more rockfish and squid. While not bad in and by themselves, squids and rockfish offer far fewer nutrients than their predator’s usual foods. And this has made a huge impact on their young.
Where’s all the healthy food?
But why are the animals eating food that isn’t that good for them? There are two equally plausible causes, although nothing can really be done in either case. After analyzing decades-worth of data on migration patterns and sea lion demographics, the researchers came up with the two options.
The first possible explanation is one of the biggest issues we’re facing today – rising ocean temperatures. Because of both global warming and the exceedingly hot El Niño we’ve had this year, the sea lions’ preferred prey has been steadily migrating towards colder environments.
The second option would be the increase in the numbers of the sea lions themselves. California sea lion populations have seen an explosion in the past four decades, their numbers increasing from 50,000 to over 340,000. With this much competition, it’ obvious that many animals have to settle for food that isn’t as nutritious.
Image source: Flickr