VIDEO: Trout never sleep

Photo and text  Tiit Hunt, www.rmk.ee
Translation Liis
 
 
River trout; Brown trout     Jõeforell or hõrnas     Salmo trutta morpha fario
 
On following what happens in the fish camera you might conclude that the spawning period is only one massive ordeal and tribulation for the trout …
 
The bickering among themselves and the threats from the shore only leave them brief moments for getting on with the vital things. The male beside the female at the nest furrow is disturbed and forced to leave the nest repeatedly to scare off intruders, young individuals of its own species. During night-time an otter has been caught in camera view; it scared off the fish from the spawning site for a long time. Extraordinarily, even a marten entered the water to explore the spawning site. So far nobody has yet noted the talons of an osprey splashing into the water to grab a trout straight from the nest, but even that is possible.
 
Despite the plentiful enemies and disrupting circumstances trout have never been as widespread in Estonia in the past as they are at present. Currently the species inhabits a couple of hundred running water courses and there are no longer any major river systems without trout. In rivers communicating with the sea, trout have come up from the sea since ancient times and in all rivers and streams where the trout come to spawn in autumn there are always river trout. In flowing water courses that have never had any connection with the sea man has planted trout already during several hundred years. 
 
At  the spawning period the belly and gill covers of river trout turn yellowish
 
Sea trout, that grow several times as large as the river trout, at the spawning ground
 
Some may ask why  river trout lives where sea trout goes spawning. But actually only one trout species lives in Estonian waters. In the case of this species we distinguish between two forms, the sea trout  (Salmo trutta truttaand river troutl (Salmo trutta trutta  morpha fario). From the young fish of the sea trout that descend the rivers to live in the sea,  sea trout grow. Those who have a genetical predisposition to stay in inland waters or whom environmental conditions will not allow to go to the sea stay as river trout.
 

Young trout. In case of small trout living in rivers it is not possible to determine from the exterior whether it is a future river or sea trout
 

Salmon
 

Young salmon
 
 


 

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