On the 7th March I posted a thread called “Hatchery fish emerge”. Of course that was completely the wrong terminology as emergence in a fish hatching context means when they lose their yolk sac and emerge from the gravel to feed. Surprised no-one pulled me up about that!
Yesterday Jimmy Woods called to say that a lot of the fish were “emerging” from the incubators into the tanks, ready for feeding. The system is designed to allow the fish to time their own emergence from the incubators. It is two months since the fish actually hatched, just shows how long the incubation period is for salmonids. I went up in the afternoon to have a look and take some photos.
A good hatchery manager is essentially a stockman; like any good stockman you have to observe your stock!
Jimmy removed the plastic substrate from the incubators to encourage the remaining alevins to take the plunge.
The fish in the tanks are now being fed several times a day and if the warm weather continues they will soon develop. The temperature in the hatchery was 11oC yesterday, the same as in the lower mainstem. The River Dulnain stock were the first stripped and they appeared to be the most advanced yesterday. If the fish are emerging at 850′ altitude in the hatchery the same will be happening with the naturally spawned fish across much of the catchment.
Jimmy reckons the mortality in the egg phase was around 1% with little evidence of mortality in the incubators.