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All ova hatched on Sanday (at last…) February 27, 2012

Posted by Mr Pietri in : Alevins, General info, Sanday , 1 comment so far

When the first ova hatched at the Sanday mini-hatchery 10 days ago, we were looking forward to seeing the bottom of the tank crawling with the transluscent pinky-orange alevins within a matter of hours or days. However, we’ve had to wait until today to discover that all the eggs (apart from maybe a dozen) had hatched over the week-end. Now (and some people are going to be disappointed when reading this ;-)), after very close inspection, I still couldn’t spot Trevor TT nor Tilly TTT who seem to have disappeared into the crowd… 

The great news is that most our ova have made it and that hopefully, we’ll be able to release about 280 alevins into Bea Loch in a few weeks.

Mr. Pietri

Sanday one day-old alevin and egg case (click on picture to magnify)

AFYD – OTFA Junior Angling Competition (03/06/11) June 13, 2011

Posted by Mr Pietri in : Fishing, General info, Stronsay , 4comments

It was on a gorgeous sunny morning that 14 pupils (4 from Stronsay JH and 10 from Kirkwall Grammar) jumped on the bus and headed for the Kirbister Loch.  Kirbister wa chosen as the venue for the competition as it usually offers anglers plenty of chances to hook trout. However, with bright sunshine and lack of wind, the conditions could be very tricky…

At 10:00, flies and baits hit the water and fish were very active on the surface, feeding mostly on midges and slightly out of casting range. The young anglers persevered and after a couple of hours, it became clear that baskets would be very light and that one fish could make all the difference at the weigh-in…

When the whistle blew at 2:00 to signal the end of the competition, the weight of the baskets didn’t do  justice to the anglers’ skills displayed during the day. However, technique and perseverance paid off for Craig Stout who won the Junior Fly section (3 fish), Jason Cook, winner of the Senior Fly section (3 fish) and Steven Newlands in the Junior Bait section (1 fish). Also a special mention to Keith Holland whose casting and retrieving technique has improved so much, who managed to bag a fish in the last half-hour of the competition which granted him 2nd place in the Junior Fly section. Daniel Carter was a lot more successful the day before, during practice and the same can be said for Kevin Kent who managed to catch a trout on the Harray Loch on his first cast!

Congratulations to all and a very big thank you to the OTFA volunteers who came to help the youngsters and to Norman Irvine and Ken Kennedy who organised the weigh-in.

AFYD-Stronsay J.H. fishing trip. June 6, 2011

Posted by Mr Pietri in : Fishing, General info, Stronsay , 4comments

On 2nd June, the AFYD pupils from Stronsay J.H descended on the Mainland lochs… It seemed to be quite a long time when they suggested in class, back in September that they would fancy a fishing trip and grilling their catch by the shore!

After the ferry crossing from Stronsay, we drove to the Harray Loch  first where the pupils had the chance to see what a 29lbs trout looks like (the one on the wall of the Orkney Trout Fishing Association hut… Then, a few casts on Harray and Kevin was already playing a beautiful Harray trout! On his first cast! No mean achievement!

The AFYD pupils from Stronsay on the Kirbister Loch (June 2011)

 Then it was time to eat our catch and Kevin’s trout tasted lovely on the barbecue!

The wind was still very strong and moving to  Kirbister Loch sounded like a good idea as it offers free rising fish and “usually” the guaranty of a good basket. However, the trout didn’t want to play ball and it was a struggle to hook a few fish.

What I couldn’t help noticing though, was how our pupils’ skills had improved over a few hours fishing! Here they were, casting a perfectly straight line, retrieving at the right pace and controling the line, rod tip down as if they had done it for years! They had become very comfortable with a fly-rod and their casting looked easy and fluid like any sport action properly executed!

Well done boys!

(More to come on the AFYD/OTFA Junior Competition)

Troot in the Kitchen… March 27, 2011

Posted by Mr Pietri in : General info, North Walls , 2comments

Preparing a Fisherman's Pie

To tie in with the trout hatching project, the North Walls secondary pupils looked at how to cook fish in Home Economics with Mrs. Groat. They chose dishes and made Fish Pie and Kedgeree. They used salmon and haddock to make their dishes.

Just click on the following links for the recipes:

Fisherman’s Pie

Kedgeree

Trout released on Meikle Water (Stronsay) March 25, 2011

Posted by Mr Pietri in : Alevins, General info, Stronsay , add a comment

Keith releasing the alevins in Meikle Water, Stronsay (23/03/2011)

This is it! After looking after our trout for the last 2 months, the time has come to release them in the wild! Unfortunately, a small disaster happened over the last week-end, when 67 alevins ready for release died. That left very few to stock Meikle Water with… However the trip to the loch was a good opportunity to look at the environment, possible ways to improve the trout habitat and also how to make “Troot in the Shed” 2012 even better!

Effects of water temperature on the alevins’ development. March 19, 2011

Posted by Mr Pietri in : Alevins, General info , add a comment

The photographs on the left were shot on 15/03/2011 on Stronsay, where the tank water temperature has been on average  2 to 3 degrees (at around +9°C) warmer than on Hoy where the pictures on the right were taken two days later (17/03/2011). Actually, the water temperature in the Hoy shed is much more similar to the one measured in the Orkney burns at this time of year (around +6°C). Look at how the yolk-sac has been nearly used up on the Stronsay fry while the Hoy alevins still have their whole sacs.

Release postponed. March 15, 2011

Posted by Mr Pietri in : Alevins, General info, North Walls, Stronsay , add a comment

One month-old alevin (Stronsay – 15/03/2011)

There was a slight delay in releasing our alevins, as we were advised by Scottish Natural Heritage to apply for a permission to Marine Scotland (Scottish Government) under the Aquaculture & Fisheries (Scotland) Act 2007. The application form for “Single Introductions” (accessible on http://www.scotland.gov.uk/Topics/marine/Licensing/fishintros) was actually relatively straightforward to fill in; it asked for details regarding the purpose of the release, grid references of the origin of the brood stock, details about the water where the introduction is going to take place, species of fish, number, age, etc…  It was dowloaded, filled in and emailed to Marine Scotland last night and we received the consents to stock unfed fry in Meikle Water and the Ore Burn by mail today before noon! A very speedy service! So, if all is well, the Stronsay fry should be released on Wednesday 23rd March and the North Walls fry on Thursday 24th.

In the meantime, we were getting worried about our alevins’ yolk-sacs which have been shrinking considerably over the last couple of weeks (especially the Stronsay ones, which hatched earlier). Fortunately, we checked them today and by the size of their yolk-sacs,  it’s safe to say that our alevins have still a few days left in the tank! (excuse the pun…) The photograph above was taken today and will give you a good idea of the stage of development our “peedie troot” are at.

Project photo-montage March 10, 2011

Posted by Mr Pietri in : Alevins, General info, North Walls, ova / eggs, Stronsay, Trout life cycle , 3comments

Clockwise from the top left corner: Testing tank water for Ph. – Ova in the tank – First "eyed" ova at North Walls – Newly hatched alevin – 3 week-old alevin hatched on Stronsay.

Our alevins on Youtube! March 5, 2011

Posted by Mr Pietri in : Alevins, General info, Stronsay , add a comment

If you’re at a loose end and that your Internet connection is fast enough (hope it’s faster than mine ;)), click on the link below to see the Stronsay alevins swimming in the tank.

Brown trout alevins

Hatching Time & ATUs… February 20, 2011

Posted by Mr Pietri in : Alevins, General info, ova / eggs, Trout life cycle , add a comment

AFYD outing at the Kirbister Loch.

This is a little bit technical but does make sense when you put your mind to it: it is recognised that from the stage of “eyed” ova, brown trout eggs need about 230 ATUs (Accumulated Temperature Units) to hatch into an alevin. 1 ATU = 1 day at a temperature of +1°C or 10 ATUs = 1 day at 10ºC.
The first eyed ova were observed on Stronsay around 20th January and hatched 26 days later; the water temperature in the shed has been averaging +9ºC so, to work out the number of ATUs we just need to apply the formula: number of days x temperature in ºC – 26 x 9 = 234 ATUs
This does explain why the ova at North Walls haven’t hatched yet. The water temperature in the shed there is about 2ºC colder and the eyed ova appeared about the same time (20/01). If we want to know when the eggs are due to hatch, we can use the number of ATUs needed for the eggs on Stronsay to hatch (234) and divide that number by the average water temperature on Hoy (+7ºC): 234 : 7 = 33.4 (about 33 days which is roughly a week later than on Stronsay).
So, as I’m typing this, if everything works according to plan, our alevins must be wriggling out of their shells right now! Don’t forget to look for the foam on the surface which is caused by enzymes breaking down the egg shells.
Let me know about any new developments on Hoy!