Smolt traps ice up

The smolt traps were installed in the Truim and Tromie last week, approximately the same date as in previous years. This time last year we were entering a period of exceptionally fine weather, its slightly colder this year. The smolt traps for the last two days were a bit like a crab boat in the Barents Sea; covered in ice and frozen solid. When we arrived today the air temperature was above freezing and it didn’t take much chipping before they were turning again.

Tromie trap immobile in the ice

Tromie trap immobile in the ice

The rotary screw traps were not designed for use in freezing conditions, to be constantly dipped in and out the river when it is minus 10oC is not a good idea.

Despite the ice there were two fish in the Tromie trap, a smolt of 100mm and a parr of 49mm.

The first smolt of 2013 and a small parr from last year

The first smolt of 2013 and a small parr from last year

The small size of the parr at the end of its first year shows why three year old smolts are the most numerous age class in this upper catchment tributary, with four year olds not uncommon.  In the lower river the fry can be as big as that by July in their first year.

It will be a month at least before the main smolt run moves, maybe more if this cold spell continues. Although very time consuming the operation of these traps in the upper river provides hard data on the Spey smolt production. This will be our fifth and fourth consecutive year of operation in the Tromie and Truim respectively. Data becomes so much more valuable and interesting when part of a long time series so we look forward to discovering what 2013 will bring.

Tromie trap operational again

Tromie trap operational again

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