the naturalist man's picture

Otter

Observed: 2nd December 2009 By: the naturalist man
The Mammal SocietyYorkshire Naturalists' Union
Mammals expert
DSC02272 small
Description:

Don't bother trying to find an otter in the photo, they are not there. The photo is to put this behavioural observation in habitat context. Taken this morning from my bedroom window.

Identifications
Species interactions

No interactions present.

Species with which European Otter (Lutra lutra) interacts

Comments

the naturalist man's picture

Otters playing

When I took the dogs for a walk this morning I heard a high pitched whistle and knew there must be otters around. I spotted them about a hundred metres ahead of me and followed them for almost an hour (07:24 - 08:15) before I lost them under the A64 bridge and remembered I should be writing a report today! I was able to follow almost on level with them (roughly 10 metres away), even though I had two dogs; the dogs were on leads to stop them swimming over to join in! The otters looked at me a few times but just carried on.

There were three otters, two were clearly a pair they were chasing each other and the slightly larger one, the male, tried to mount the other on at least four occaisions, each time she turned and snapped at him resulting in lots of whistles, squeeks and tustling.

The third seemed to be just tagging along for the ride for the most part staying around 10 metres behind the other two often mimicing their actions on its own. I assume it was the female's young from last year; they can stay with their mother for up to 15 months. It was tollerated unless it tried to join in when both of the pair would snap at it and chase it back down the river - this happened seven times in the hour or so I watched.

As you can see from the photo the river is flooding at the moment. This led to an interesting observation, even though the river has topped its banks the otters followed the line of the almost invisible far bank until they reached a point where the bank is higher and out of the water. Here they continued along the bankside but were out as much as in the water.

I watched them doing various behaviours associated with mating 'play', including; play fighting, mounting, porpoising in the water, diving whilst clasping each other, pulling on each others tail and generally chasing each other. If I were to anthropomorphise I weould describe the behaviour, except perhaps the mounting, as being like two boys playing rough and tumble.

I see otters on the river three or four times a year, usually whilst walking the dogs. However, this is the first time I've watched them for so long or seen such a range of behaviours. Usually they swim faster than I can run to keep up, or disappear soon after I've spotted them.

Otters had become extinct on the Derwent until a release programme in the early 1990s. Now they are doing so well they are moving onto adjacent river systems including the river Hull.

Graham Banwell

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