Release of the North Walls alevins!

A big thank you to Jim Erskine from whom I received this very detailed report this afternoon and to Sarah for emailing me the photos:

Thursday 24th March was the chosen release day for the North Walls troot. Unfortunately the weather forecast was too bad to allow the pupils to walk down to the Ore burn. However, the fish tank was carried from the shed into the school and all the pupils from Primary 1 to 7 enjoyed netting a few of the very lively alevins and transferring them into polythene bags. Group and class photos were taken, before Trish and Jean transported the bags by car to the Ore burn. Most of the 120+ fish were released just above the bridge, but a couple of bags were carried much further up the burn. The pupils also got the chance to examine some of the small invertebrates the adult trout feed on. Congratulations to the pupils and staff on once again achieving a very high survival rate. Acting headteacher Jean Ward led the project, ably assisted as usual by Trish and Olivia, who have been involved for more than 5 years.

The P3-4 pupils learned about the brown trout and sea trout life cycles. The Atlantic Salmon life cycle was studied by the older pupils and they found that the life cycle of the sea trout and salmon are the same from ovum to smolt, but that salmon then use the Earth’s magnetic field to navigate all the way to the Faroe Islands or Greenland to feed, whereas the sea trout don’t usually venture more than 40 miles from their birth burn. Although the lack of rivers means that wild salmon don’t often appear in our burns and lochs, Orkney is famous for its production of high quality farmed salmon. The children also learned how to tell a salmon from a sea trout; in particular that salmon have very narrow tail necks ( they can be picked up by the tail ) and very few spots below the lateral line.

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