Monday, 1 May 2017

Tricked by a Seal - what counts as normal behaviour?

Last weekend at the beach, we saw a fur seal (kekeno) holding one flipper in the air for a long, long time. It's not surprising that some people thought what they were seeing was a dolphin fin, but I recognised this seal pose from a previous encounter.

Seals have tricked me before with their one-flipper pose. A month ago, I saw a seal hold this one-flipper pose for much longer than ten minutes. I began to worry that it was injured. Only after I had called the DOC Hot Line and was speaking to someone there, did it roll over and clap its flippers together as if pleased by the joke.
Seal - thermal regulating

I thought that it must have been having a rest, but a friend explained that what the seal is doing is called thermal regulating. Holding a flipper out of the water helps it either cool down or warm up, depending on the sun and the wind.

This works because the water temperature is different from the air temperature. It's like sticking you leg out from under a duvet or blanket to cool down if you are too hot at night.

There's a great article about seals and sea-lions thermal regulating from the Australian Marine Wildlife Research and Rescue Organisation  who apparently get lots of calls like my one to the DOC Hot Line.

 DOC have their own advice page about fur seals, which points out that 'drifting in the waves' and 'flapping its flippers in the air as if stranded' are normal behaviour! It seems the only times to be concerned about fur seals areif they are 'severely injured', 'entangled in marine debris' or are 'being harassed by people or dogs'.
A fur seal/kekeno resting on the beach- normal behaviour!

If you see a seal behaving normally, there is a different kind of reporting you can do. Scientists are interested in sighting of fur seals, especially perhaps where they are seen less often. You can report your sighting on iNaturalistNZ and if you live around Taranaki to Project Hotspot. Reporting seal sightings helps scientists learn more about the population.

More information about fur seals:
The Seal Deal: caring for kekeno together -
Project Hotspot
Fur seals are 'Eared' Seals