Chasing Sea Trout and Otters

posted in: Uncategorized | 0

By Russell Wynn, 19 December 2015

For several years Otters have been regularly recorded from major river valleys and estuarine sites around the margins of the New Forest, but there are very few direct observations (and even fewer photos) of live animals from the interior. The small number of records on the open forest in recent years mostly relate to indirect evidence (e.g. spraints) or animals killed on roads near to streams. Most records are in the winter months, and it seems likely that Otters occasionally follow Sea Trout upstream at this season as they return to their spawning grounds.

Sea Trout are a form of Brown Trout that migrates to coastal waters to feed and grow, before returning to the upper reaches of natal rivers to spawn. This migratory form appears to be particularly abundant in the New Forest, possibly because the relatively low productivity of forest streams and rivers encourages trout to seek richer feeding grounds offshore. Their early winter journey, back upstream, sees them crossing unfeasibly shallow gravel riffles, and obstacles such as fords and log-jams, where they can be encountered by the patient observer.

Two weeks ago I deployed two camera traps onto a New Forest stream (under licence from the Forestry Commission) in the hope of capturing images of wild Otters. The cameras were targeting shallow riffles, where any Otters moving up or downstream would be clearly visible.

 

A view from one of the deployed camera traps, showing a shallow riffle in a New Forest stream. A Sea Trout was encountered in the shallows at this site.
A view from one of the deployed camera traps, showing a shallow riffle in a New Forest stream. A Sea Trout was encountered in the shallows at this site.

 

Today, accompanied by my partner, Vikki, I checked the two camera traps to see what had appeared in the first fortnight of deployment. While checking the first camera, a loud splash in the stream below alerted us to a rather battered and apparently moribund Sea Trout trapped against a shallow riffle, although it swam off strongly when I gave it a nudge into deeper water.

A few hundred metres downstream, we found another Sea Trout, roughly 50 cm long, wedged against a fallen branch in the shallows. This one was recently expired (presumably having finished spawning), and was therefore somewhat easier to catch and retain for a photo! It is amazing to think that these large fish regularly pass through tiny streams in the middle of the forest, and one can see why an Otter would be attracted to such a bounty.

 

Russ with a good-sized Sea Trout (recently deceased) recovered from a New Forest stream.
Russ with a good-sized Sea Trout (recently deceased) recovered from a New Forest stream.

 

And what of the camera traps? Well, there were no otters (yet), but a few Fallow Deer, a Fox, and two Dogs provided reassurance that the cameras were functioning correctly. Other wildlife seen around the camera sites included Kingfisher, Grey Wagtail and three over-wintering Firecrests. We’ll say a bit more about camera traps and how they work in a later post, but for now let’s keep our fingers crossed for that first otter photo!

Background information about New Forest Sea Trout can be found in the ‘South Coast Sea Trout Action Plan’ at the link below:

http://wildtrout.org/sites/default/files/projects/South%20Coast%20Sea%20Trout%20Action%20Plan.pdf

 

 

Leave a Reply