Our article will tell about unusual fish - shovels. Unfortunately, most species are under threat of complete extermination, despite all the efforts of environmental organizations. Uncontrolled catch has led to a critical decline in virtually all populations of shovels.
These fish live only in clear water of the rivers. Each of all existing related species occupies its territory, the ranges do not intersect.
Shovels and pseudopatonids
The sturgeon family includes several subfamilies and genera. Shovels and pseudopatonos are related genera that have more common features than differences. But still they should not be confused.
Two species of fish that live only in North America are classified as shovelnose. Russian species belong to the family of pseudopathos. But even in the scientific literature, a false particle is usually omitted.
Shovel American
The genus Shovelnose Scaphirhynchus is distributed in fresh water bodies of the Mississippi River Basin. The name comes from the Greek language and is a tracing-paper of the words “snout-shovel”.
The nasal part of the shovelfish fish is strongly flattened and stretched forward. The caudal stalk is elongated and the whole is covered with rigid scales.
The common shovel can reach a length of 90-100 cm. The average weight is 3.5 kg, but many cases of catch of larger specimens are known.
White shovel (or pale), as the name suggests, has a light color. This is the largest variety, in length it can reach one and a half meters. The species is listed in the Red Book. White Shovel was the first inhabitant of the Missouri basin to be at risk of extinction. Environmental organizations and US authorities are conducting a number of events, although it’s too early to talk about success: the number continues to decline smoothly.
Great Amu Darya Shovel
This species is slightly smaller than the American relative, its length usually reaches 75 cm, but isolated cases of catching especially large specimens about 130 cm long are known.
At the end of the snout of this representative of the sturgeon family, as well as on the back of the head and between the eyes there are sharp spikes. The nasal part, as in the ordinary shovelnose, is flattened, but not elongated. The mouth is large, adapted to bottom nutrition.
Unlike shovels, pseudopatonids have a very long tail thread. The back is colored brown, the belly is always lighter.
A variety is widespread in the Amu Darya River, from its mouth to the Panj. Usually this fish does not go to sea, but several specimens at different times were caught in the waters of its delta and the pre-mouth area. Currently, only two populations have survived: one of them in Vykhsh, the second in the middle reaches of the Amu Darya, above Turkmenabad. Several centuries ago, the range was more at times.
This species has two biological forms that are not isolated into separate breeds. They differ only in size: along with the large Amu Darya, there is a small shovel.
Adult shovels are fed, usually fish (char, barbel). Juveniles eat mainly insects and their larvae. The food competitor of the adult Amudarya shovel is a catfish.
Maturity occurs around the seventh year of life, when the body reaches 45 cm. Fish begin to spawn in April, at a water temperature of 16 ° C.
The eggs are small, black. A female can bring from 3 to 36 thousand eggs in one breeding season. Fry is born in the summer. In length, they do not exceed 2-3 cm. Newborn larvae are adapted to live in water with a strong current. The tail thread begins to appear when the body length reaches 6.5 cm.
Syrdarya Shovel
Despite the fact that this medium-sized species (up to 27 cm) did not have commercial significance, there is reason to believe that it is completely destroyed. Earlier, shovelnose fish was found almost everywhere in Karadarya and Syr Darya, but the abundance was greatly reduced due to the withdrawal of water for irrigation of fields, as well as due to water pollution by drains.
Since the 70s of the last century, no cases of capture of the Syr Darya shovels have been recorded. But scientists have the hope that a small population can currently survive in the upper reaches of the river.
Security
They tried to acclimatize the Amu Darya shovel in the Murgab River (Turkmenistan), but the fish did not take root. There are several attempts to create species of sturgeon farms, but so far it has not been possible to achieve significant success. The Red Book defines the Amu Darya species as being on the verge of extinction. Fishing is strictly prohibited by law, habitats are state reserves.
The American common shovel is a fish that does not have much commercial value, but it is also considered to be at risk. The main measures aimed at maintaining the number of employees is a set of measures to combat poaching.
White shovel is the only species that people breed on sturgeon farms, however, in small quantities, insufficient to restore the former population. The authorities are trying to conduct educational work, explaining the importance of preserving each species, calling for abandoning inhumane catch methods and recalling the consequences of poaching.