Saturday, December 10, 2011

They Call Him Flipper

Dolphins are charismatic, no question about that. They play, they learn, they do amazing acrobatics. Their smiling faces draw people to aquatic parks worldwide. The freshwater dolphins have gotten some press lately, but they aren’t the prettiest dolphins around.

I suppose the Gharial-like snout on the Ganges River Dolphin (Platanista gangetica) is what bothers me about it. Its stubby dorsal fin gives it a humpbacked appearance that is far less pleasing than the torpedo-shaped marine dolphins we’re used to. However, both of these serve an important purpose: maneuverability. The shorter dorsal fin allows for faster turns, and the thin, tooth-filled rostrum is perfect for slashing sideways into an unsuspecting fish.

The Ganges River Dolphin is also effectively blind. The lack of a lens means that any light entering the eye is only seen as unfocused blurs of shadow. However, for a creature with echolocation living in the silt-filled rivers of India, this is less of a problem than one would expect.

As those silt-filled rivers are in some of the most densely human populated areas of the world, you can expect there to be some environmental issues. Damming, pollution, boat traffic, and by-catch are all problems that this blind dolphin faces. The Yangtze River Dolphin faced similar problems, and is now listed as “functionally extinct”.

The Ganges River Dolphin may have some support to save it from that fate. Dolphin reserves are being established, and the WWF is trying its darndest to educate the public. India even named this dolphin the National Aquatic Animal. However, there is still a lot of work to be done to make sure it doesn’t go the way of the Yangtze River Dolphin.


Celebrity said...

Thanks for the info. I love nature and creatures!!

Entertainment said...

Dolphins are way intelligent fish!! Nice blog.

Garfman said...

Entertainment, they're not fish. That's one of the first things you need to learn about dolphins. Their closet relatives are hippos.