American Cancer or Signal Cancer

A medium-sized bluish or reddish-brown cancer (length 7-13 cm), with massive and blunt claws, under favorable conditions the signal cancer can reach a length of 17 cm. A very characteristic sign at the base of the joint of the claws is a large whitish to purple spot, which is not found in any other species of crayfish found in Latvia and which is clearly visible in both young and adult specimens. Life expectancy - up to 16 years, in particularly favorable conditions - up to 20 years.

Lifestyle

In terms of lifestyle, it occupies similar habitats as the broad-billed crayfish, but being more disease-resistant and self-transmitting, the signal crayfish is a serious competitor to local crayfish. Lives in rivers, lakes, drainage canals, digs caves. Omnivore. 200-400 eggs in one litter, sexual maturity is reached in about 3 years.

A gentle peacemaker

Signal crayfish prefer streams, rivers, lakes with distinct caves and good water quality. Sensitive to environmental pollution and physical degradation of the environment. It spreads thanks to economic indicators (it reaches the standard 1.5-2 times faster), Signal cancer is more resistant to rapid temperature fluctuations and low temperatures, babies survive in pools and ponds, if the temperature temporarily reaches even 28-30 C.

In the area between the toes of the signal crayfish's claws, there is a well-defined purple spot, with which it signals belonging to its own species. It is easy to recognize the signal crayfish from others also by its aggressiveness - pulled out of the water, the broad-clawed crayfish is calm, but the signal crayfish tends to go "crazy" and can reach its tail by bending with its long claws. Thus, it is not uncommon for them to "bite" the fingers of a fisherman with their claws, who is used to ta

A couple of years ago, in the lower reaches of the Salacas River, in the territory of the Northern Vidzeme Biosphere Reserve, a licensed catch of the alien species - signal crayfish - was organized in order to rid the river of the alien species.

Lielupē savairojušies kaitnieki

Amerikas vēži, kuri ievesti Latvijā 1971. gadā. Signālvēzis pakāpeniski izplatījies gan ezeros, gan upēs. Tā kā signālvēzis ir izturīgs pret vēžu mēri un vienlaicīgi šo slimību pārnēsā, tas pamazām sācis dominēt, aizstājot vietējo platspīļu vēzi. Tādas svešas vēžu sugas kā signālvēži ar savu agresivitāti, ātro vairošanos un izturību pret slimībām apdraud vietējos platspīļu vēžus, izspiežot tos no dabiskās dzīvesvietas.

Catching crayfish

It is important to know the crayfish fishing rules for a specific water body where you will catch crayfish. Important! Use fresh fish, meat as bait. Fresh not spoiled remember that. 1. Picking by hand. 2. Chalks. 3. Cancer killers.

Hand picking

1. Picking by hand. Prepare tree branches, sharpen their ends. Pierce the tree through the bait. Poke the trees with the bait in the water along the shore at a depth that you can reach with your hand. Every 2 m. When you are done, wait 30 min and go check. There will be crayfish around your bait that you have to carefully pick off one by one. This happens at night, you need to use a night light. Crayfish start feeding when the sun goes down. 2. Catching crayfish from caves. There are caves along

Cancer with a crayon

You put the bait inside the net, fasten it with a clip or wire so that the crayfish cannot drag the meat away. You drop the crayon into the water every 2-3 m. After 30 min go check. Drag the crayon up behind the float and select the crayfish caught in it. It happens at night when the sun has set.

Catching with murder

The most convenient way of catching. The advantage is that you put them in overnight and check them in the morning. Place the bait inside the hole. Drive the boat to the places of your choice, place the traps in water depths of 1-6 m. In the morning, when the sun has not yet set, go to check. Crayfish will try to get out of the hole, so check as soon as possible.

Transportation

Place crayfish in boxes, can be covered with freshly picked nettles. Nettles provide cold temperatures. Moisten if necessary. Crayfish should be in a humid environment and in the coldest air temperature possible. It is better to use the air conditioner in the car during the summer, for short distances it is enough to open the window of the driving car to change the air. The main condition is that the crayfish should be covered with nettles in the shade, there should be some humidity, fresh air i