Otter questions

[stripee]

I found another otter spraint this week in a small stream on a rock, these are regularly deposited every few weeks. Would the dog otter be using the stream as the end of its territory? There is not a lot that's edible to be seen in the water, some tiny fish, caddis fly larvae etc. Could an otter be sustained on this kind of thing or would it need to travel downstream where the fish are bigger. Do they eat food on land as well?
Also how much toleration of other dog otters is there? Is only one dog on each stretch of stream or do the male cubs as they grow up have to disperse far away from the adult males to avoid conflict, is it possible for several males to share an overlapping stretch of water? I know they can have bad fights and I've read they sometimes resort to eating cubs.

[coasty]

I am no expert but I do love otters and am fortunate to live right near an occupied holt. So get the odd sighting and see the signs of them. As I understand it an Adult Dog Otter can have a very large territory this will overlap several female otter territories as the females have a smaller territory that is capable of sustaining her and her pups. It is unlikely that the habitat you describe could really sustain a resident but as you rightly say it may well form part of a larger territory.

[shirl]

I am not an otter expert, but from what I know an adult otter would need to eat up to 1.5kg of food per day, prey would include eels (their favourite)fish and crayfish - sometimes even birds, small mammals (e.g. voles) frogs and snakes. So the little stream is unlikely to sustain it for any length of time. I believe they generally don't hunt in the same spot for more than a couple of nights ensuring that the food supply isn't depleted. In Derbyshire, otter signs have also been found at smaller watercourses. Spraints are left as territory markers and I think also as communication - a female may be advertising the fact that she is ready for mating.

They are solitary, and come together for mating only. The dog otter's territory can be 20 km or more, the bitch up to 14km, territory size is likely to be based on the amount of food available. Male otters leave the female shortly after mating. Territories are guarded fiercely, I think I read somewhere that if a male otter is killed, another will "move in" and this may be when any cubs could be killed ( as in the case of lions).

I think cubs stay with the female for up to a year and then they go off to find their own territories.

Shirl

[RobSutton]

They'll use small streams as routes between larger bodies of water, between the sea and a freshwater lake or between two lakes for example. So perhaps it was just on it's way somewhere else.

[stripee]

Originally Posted by shirl

They are solitary, and come together for mating only. The dog otter's territory can be 20 km or more, the bitch up to 14km, territory size is likely to be based on the amount of food available. Male otters leave the female shortly after mating. Territories are guarded fiercely, I think I read somewhere that if a male otter is killed, another will "move in" and this may be when any cubs could be killed ( as in the case of lions).

I think cubs stay with the female for up to a year and then they go off to find their own territories.

Shirl

If the dogs are highly territorial, this would have an effect on the numbers of dog otter cubs finding new territories and possibly limit numbers? Although in a big enough river, I guess they can avoid each other.

Originally Posted by RobSutton

They'll use small streams as routes between larger bodies of water, between the sea and a freshwater lake or between two lakes for example. So perhaps it was just on it's way somewhere else.

There are sightings further downstream and in the river. The coast is only 20km away so I suppose they can easily have a territory from small tributaries right down to the sea.

So not much chance otters will be living here then, you are lucky to see them, coasty, and be near a holt.

[shirl]

Originally Posted by stripee

If the dogs are highly territorial, this would have an effect on the numbers of dog otter cubs finding new territories and possibly limit numbers? Although in a big enough river, I guess they can avoid each other.

They are highly territorial and even dogs and bitches do their utmost to avoid each other except for mating time. The young otters have to disperse, and there is always a risk that they cannot find suitable territory where there are no other otters claiming stake to a stretch of water, in which case they may not survive. If your otters have access to larger water courses and indeed the sea, there are lots of opportunites for them to thrive.

Shirl

[coasty]

Was fortunate enough to watch one for a while last night , Have made a post in the treehouse forum...