This year’s Clyde in the Classroom project came to a close yesterday, as the last of the classroom-raised brown trout were released into the wild. With 79 classes taking part, we’ve enjoyed a busy few weeks helping to introduce the little brown trout fry to their new homes. We received some fantastic entries for the Clyde in the Classroom competition this week, which will be judged after the Easter break – good luck to all who entered!

I’d like to say a massive well done and thank you to all who took part this year, including those who came along to help out with the release days. Thanks again to all our sponsors. Although we’ll have to wait another year for the next Clyde in the Classroom, the adventure is only just beginning for these amazing little fish! Here are just a few pics from the release days…

Wow, what a busy few weeks it’s been! I’m happy to say that all of the trout eggs have now hatched and the pupils have been working very hard to look after their underwater classmates. I’ve been taking photos to track the development of the alevins from hatching – see the pics below!

David and I arrived at one school just at the alevins were starting to emerge. I’ve circled one newly-hatched alevin and one that is just hatching – you can see its head poking out of the egg.

Some of the other eggs have changed shape slightly and you can see the fish curled up inside, ready to hatch.

Once the fish hatch, it’s important to keep the water nice and clean. Any leftover egg shells can make the water foamy so it’s important to remove them and scoop out any foam from the surface.

These alevins are around 1 week old. They are very pale with a large orange yolk sac. At this stage they spend most of the time resting on their sides at the bottom of the tank. In the wild these fish would still be hiding in the redd.

This week, a lot of the alevins are darker in colour and are starting to look more like little fish. They are still pretty tiny (around a couple of centimetres long), so here’s a close-up pic of some we’ve been looking after in the Clyde River Foundation lab.

We’ll be keeping a careful eye on the yolk sacs over the next couple of weeks. As soon as the yolk sac is used up, the fish need to start feeding on aquatic insects and that means relasing them into a burn. Look out for Release Day updates soon!

This week we’ve been out and about delivering the trout eggs to the classroom hatcheries. Deliveries were delayed last week due to bad weather – not for us but for the eggs themselves! It’s been colder than normal at Howietoun Fish Farm and this slowed down the development of the eggs. Trout do like it cold but the colder it is, the longer it takes to reach the “eyed egg” stage.

By Monday we were ready to go, with 250 eggs for every class. With 79 classes taking part, that’s a whopping 19,750 eggs in total! The eggs were kept cold in the Clyde River Foundation lab until delivery time, when they were carefully transported into the schools.

A bag of eggs – those tiny black dots are fish eyes!

All of our classes have been working hard over the past couple of weeks to regulate the water temperature of their tanks. With the help of home-made ice packs, the water can be kept nice and cold, just like in the wild. Here is a picture of Clober Primary School’s hatchery, complete with eggs:

We will be out every week to check on the hatcheries, so expect lots more updates as we see the trout develop!

When we’ve not been giving talks about fish, we’ve been busy building fish hatcheries in our “hatchery workshop” back at the Clyde River Foundation. This is the biggest year for Clyde in the Classroom so far and Caroline the gang have been working round the clock to make sure we have enough tanks for everyone!

All of the hatcheries are now complete and have been delivered! We took them out at least a week before the eggs are due, to give the classes time to practice keeping the water cold enough (8-10 °C is perfect!).

Some classes have already started making fishy artwork to decorate the class – here is a fab drawing from Castlehill Primary School!

Next up on the blog…eggs!