What kind of water to sea lions in zoos need?

July 20, 2009 2:38 AM

Do sea lions in zoos need to have salt water to swim in?

I saw a video about sea lions in the Pittsburgh Zoo. Pittsburgh is pretty far far from the ocean, so any sea water for the animals would have to be artificially made.

I know that different species of fish are very specific about whether they need salt water or fresh water, but what about seals and sea lions? Is it necessary to provide them with salt water, or are they just as happy swimming around in fresh water?

posted by edavidoff to Science & Nature (5 answers total)

While all of the smaller aquatic mammals (as far as I know) can survive in fresh water, there are two problems:

1. They are less buoyant in fresh water, so staying afloat and swimming is slightly harder, and may cause stress.
2. Their skins tend to stay healthier in a more saline environment; in fresh water, marine mammals appear to be more prone to skin infections and parasites.

Many species of dolphin live in fresh water. There are instances of California sea lions living in fresh water (rivers and lakes) and in captivity. One example is at Longleat in the UK, where they supplement the diet of the sea lions with salt tablets, presumably to compensate for the lack of sodium in the water the animals are drinking.
posted by le morte de bea arthur at 3:06 AM on July 20, 2009

I'm not entirely sure of the answer to if the NEED salt water but when my hometown zoo had sea lions (now replaced with penguins) there was a pool in the back that you could see part of if you were a visitor. It had a sign that said something like this was a Salt Water pool for the sea lions to hang out in every couple of days - my understanding was that they rotated and only one was in there at a time. It did mention something about helping their skin. I never understood it because I always assumed their regular pool was salt water but I guess maybe it wasn't.

I'm not sure if they've altered the regular pool to salt water now that they have penguins in it but I know the back pool has now been opened as a display for another animal and the penguins do not hang out back there.
posted by magnetsphere at 8:05 AM on July 20, 2009

The zoo school I went to had a sea lion in a pool that was freshwater, she never seemed to have any problems with it. Mind you, it was kept very scrupulously clean.
posted by The otter lady at 10:24 AM on July 20, 2009

One zoo has gotten rid of its sea lions because it can't afford to convert the freshwater system built a generation ago.
posted by dhartung at 12:41 PM on July 20, 2009

This page of Zoo encyclopedia implies that sea lions are not all that fussy and are often kept in fresh water.
posted by nowonmai at 5:02 PM on July 22, 2009