Fish feel the cold
Trout do not hibernate
Trout do not hibernate
The days are getting cooler and the first snow has even fallen. The water temperature in the Thur is currently around eight degrees Celsius, and the trend is falling. How do the brown trout stand it? Do you bed yourself softly in the river bed and do you hibernate?
The days are getting cooler and the first snow has even fallen. The water temperature in the Thur is currently around eight degrees Celsius, and the trend is falling. How do the brown trout stand it? Do you bed yourself softly in the river bed and hibernate?
“No,” laughs the cantonal fisheries supervisor Christoph Birrer. “Unlike mammals or us humans, the brown trout adapts its body temperature to the water”. The colder it gets, the less food she eats and the more economically she uses her energy.
The fish usually stands still in the water, its head turned against the current, and hardly moves visibly.
I stay where I am
Whenever possible, the brown trout retreat to a deep water hole. But because they are not schooling fish, the best spots are soon occupied by the stronger animals and the smaller ones have to look elsewhere, says Christoph Birrer.
Places behind stones are popular with the younger fish. The place that the fish occupies in late autumn, it hardly leaves without disturbance until spring. Trout are not bothered by the fact that the river carries less water in winter. «Colder water contains more oxygen. That's why the fish don't feel uncomfortable even when the water level is low, ”explains Christoph Birrer. And because the water in a river never freezes completely, the brown trout have no problems.
Do not disturb!
The situation is different with stagnant waters. “The lake trout can also overwinter well in Lake Constance,” explains the cantonal fisheries supervisor Fredi Fehr. Even when the surface of the lake is covered by a layer of ice. It gets trickier with small ponds, because a gas exchange is necessary so that oxygen for the fish can get under the ice layer and digestion gases can escape.
“This is the case, for example, where reeds or deadwood protrude from the ice,” explains Christoph Birrer.
Similar to wild animals that need to rest in winter, fish are also very sensitive to disturbances. One such option is ice skating on a frozen pond. "The fish begin to move too much, which can be fatal," says Fredi Fehr. The energy requirement increases, but the fish finds less food in winter than in summer. (sas)
- Do you have a pet dinosaur
- Have you ever eaten potted meat
- Will human labor survive the robotics revolution?
- Are lonely pairs of sigma bonds
- How do I make ramen eggs
- Why does a cannabis pharmacy need security
- What are the benefits of the jump instruction
- Bitcoin ATMs are available in the US
- Intuition comes from experience
- What if my laptop turns off automatically
- Where is tsungtso in china
- Can't you ever not exist
- Is introspection objective or subjective
- Will be President of Beto ORourke in 2021
- Can Sharia law be ethical?
- How does an internal combustion engine work
- There are product management courses
- Is Jesus a historically recognized figure
- How big can a helicopter be
- How does homelessness affect young people?
- What limits can you legally cross?
- Are power poles harmful electromagnetic radiation
- Can we extract data from DNA
- Birds feel delighted when they fly