Otter spraint

[scott75]

Hi,

I live by a river and have noticed a spot on the bank that had otter tracks and spraint. The spraint was sat on a stone. It was fairly recent as it was still green and moist. It seemed to be mainly fish scales and bones. A couple of days later there was a new spraint. I guess it's a territorial thing.

Does anyone know how often an otter may visit the same site?

Thanks,
Scott.

[Dogghound]

An otter will repetatively visit the site to spraint as this is marking its territory. The number of times one visits as site is dependent on a variety of factors, such as territory size and the location of the spraint site within the territory. Some sites are used every 24 hours others less frequently.

[nigel_b]

The area that I have been watching seems to be re-visited about every 3 days, sometimes up to a week.

[valleyforge]

Hi scott75 and welcome to the WAB forum.

Spraint, when it is placed prominently on a rock, log, tusset of grass, or even a purposely built pile of sand, can most probably be correctly interpreted as an 'otter postbox'.

By that I mean it is most likely designed as a means of communication between neighbouring otters, than as a 'this is my territory ... stay out' signpost.

Otters typically have large ranges, which often overlap, so that the boundaries between 'territories' are 'soft' rather than 'hard'. The ranges of males (which may be up to 48km) tend to be much longer than the ranges of females, such that the range of any male may encompass that of several females.

What's probably worth mentioning (because it appears that even some mammologists get confused) is that spraint deposited in this way as a 'marker', is quite distinct from the normal defecation of the animal ... that is the normal function of ridding the body of solid waste matter.

Because all mustelids, including otters, have rather short digestive tracts, they tend to defecate fairly frequently ... every two hours or so. Mostly they will do that in a corner or against an object (i.e. not on top of it) ... around the sleeping quarters there will be a definite latrine ... whilst when out ranging, just about any convenient spot will do. Around nursery holts though, the female will often cover the latrine to help disguise it.

What's important to note is that only marker spraint is deposited prominently, and at certain chosen locations. Spraint is undoubtably added, not just by the otter that 'started the post', but by neighbouring otters, and perhaps by those 'just passing through'. So it becomes effectively a collection of 'calling cards' that may be added to for many years, and presumably by successive generations too.

I don't think we know enough to say if an otter will re-spraint on that spot at every visit, particularly if his or her scent is still the most recent or dominant. We can also only speculate just what information any otter might glean from the scent post, but we might consider that it may be able to dermine the sex, sexual maturity and perhaps even the individual identity of a particular neighbour (if it was for instance a sibling or other clan member).

Hope this helps ... wishing you happy otter observations.

[scott75]

Thanks for the replies. That's brilliant. It leads me on to another question!

Is there a recognisable difference between male/dog and female otter spraint? Or, apart from the diet, what else can I learn from looking at the spraint?

[valleyforge]

Originally Posted by scott75

Is there a recognisable difference between male/dog and female otter spraint?

Not so much as I personally have ever been able to discern ... however Hans Kruuk (in Otters: ecology, behaviour and conservation) has observed that spraint from adult male eurasian otters is frequently very much smaller than from females, with the largest spraint being produced by adolescents.

I would surmise that this may be explained perhaps by males having larger ranges, and so their 'reserve' of spraint has to be meted out over a greater number of sites. That's only conjecture of course ... I don't know for sure ... however, what seems to be generally accepted by a number of observers is that the rate/regularity of sprainting is fairly constant in males, females and juveniles, which seems consistent with the view that the otters are employing this means to advertise their use of a particular feeding resource ... whereby any later visiting otter can determine if any favoured feeding site has already been visited, and perhaps temporarily depleted, by another clan member.

So, in effect, the use of signalling by means of spraints permits the partitioning of resources within a group territory, without need for direct confontation with other otters.

[scott75]

Thanks valleyforge for very informative replies.

I think that even though a spraint may not tell me a lot about the individual otter, it certain informs me about the behaviour of them as a species in general.

Thanks again!

[bigdave60dog]

I live in area where I have otters literally passing my front door every day (and back door for that matter) Yet it is very rare that I could predict when I could see an otter. As far as I can tell they don`t have a lot of routines that go by time other than being most active of an evening and morning.
I think that our otters activities are moulded by the tides as are our so it may be different according to geography.
Dave

[valleyforge]

Originally Posted by bigdave60dog

I live in area where I have otters literally passing my front door every day (and back door for that matter) Yet it is very rare that I could predict when I could see an otter. As far as I can tell they don`t have a lot of routines that go by time other than being most active of an evening and morning.
I think that our otters activities are moulded by the tides as are our so it may be different according to geography.
Dave

I think that's a very valid observation and fair comment Dave. These are the choices and determinations of individual animals ... and so we can't fairly just assume that all otters, or members of different otter clans, will behave in exactly the same manner as those studied elsewhere.

There are any number of factors that could/would determine how or when otters will use the resources available to them.