Sea Mouse Hunt

December 13th, 2007

The full moon of late November shone down on our second sea mouse (Aphrodite aculeata) survey in Loch Fyne. There had been an unusual sighting several years ago, of 8 or 12 sea mice in close proximity and in shallow water, whilst on a weekend dive trip with Preston Sub Aqua Club. Since then we have arranged two expeditions with PSAC and our local MCS group to survey the area and look for any repetitions of this sighting.

Aphrodite is a segmented marine worm, not rare, but in our experience only seen occasionaly as solitary creatures.  To see a cluster like this is certainly unusual, and with limited information available on their life cycle, may be related to spawning activities. The creature is an unusual looking worm, about the size of a mouse, and with ‘mousy’ brown hairs (setae) on it’s back. One of the most unusual features is an array of iridescent hairs around the base of the body. These hairs are being studied with a view to developing high-tec photonic systems.

The surveys so far have only been a partial success, in that we have found sea mice, but not in significant numbers. On the Saturday we suffered severe windchill in the 2 Preston boats that were used, with rain squalls thundering up the Loch. Sunday was much more pleasant starting with flat calm water and patches of sun breaking through the cloud, though later the windchill meant that hats were still needed. One hat left in the loch-side accomodation meant that a diver who usually has more sense, had to protect his head with a borrowed white towel. It created the strange appearance of Mother Theresa cruising up the loch with her diving flock sat around her feet.

On this occasion we found three sea mice,  two of which were in close proximity, but no larger clusters. The question is wether this is significant, or would 14 divers have seen this number on any similar substrate at any time of year? One appealing option for the future is to survey the same area, at a different (warmer) time of year. Certainly the attractive accomodation and the two groups cameraderie make this a likely option for next year.

Gordon.

Posted in dive trips, Science