Cow fish (Uranoscopus scaber) - a representative of the near-bottom ichthyofauna, belonging to the stellate family (lat. Uranoscopidae). This species has several interesting features of appearance with which the origin of its names is associated. In addition to international Latin, the fish has 2 Russian names: sea cow and European stargazer.
Biology features
The European stargazer is a medium-sized predatory fish that is ideally suited for living at the bottom. A swimming bubble typical of many pelagic representatives of the ichthyofauna is absent in the sea cow.
In addition to the appearance, this species has a number of interesting biological properties, including:
- virulence;
- secretive lifestyle, involving burrowing in the ground;
- bioelectroluminescence.
The body of a cow’s fish has a special organ that acts as an acoustic device. It is capable of generating not only sound, but also electrical impulses. The latter are of 2 types:
- short - caused by mechanical stimulation and lasts about a millisecond;
- long - typical for the spawning period, the duration of the electric shock is several seconds.
An electro-acoustic organ can be used for three tasks: detecting prey, paralyzing with electric shock, and scaring away predators. The sea cow has 2 such devices, each of which is located behind the eye.
The stargazer’s head is equipped with tubular nostrils through which water enters the gills when the fish are buried in the ground.
origin of name
The Latin name of this species literally means "observing the sky." Such an association arose because when you look at the fish it seems as if it is looking up. And indeed, the perspective of the starship should cover the body of water above the animal when the body of the predator is almost completely buried in the ground.
The second component of the species name (scaber) in translation means "roughly", which indicates the stiffness of the celestial integument. This is especially true for the head enclosed in a shell of rough bone plates.
Uranoscopus scaber received the Russian name "sea cow" because there are two spikes on its head that look like horns.
Appearance and photo of a sea cow fish
The European stargazer has a rather original appearance. It is characterized by an elongated spindle-shaped body up to 35 cm long. Sizes in males are slightly smaller than in females.
The head of the starship is slightly flattened in the vertical plane, which can be attributed to the characteristic signs of the existence of a benthic type in the biotope. The stargazer’s mouth is very wide, has a U-shape. On the lower lip, lined with teeth, there is a fleshy outgrowth supported by a thin thread. It serves to attract prey.
In the photo, the cow fish looks like a massive marine animal with a disproportionately huge head and a narrowed tail. When viewed from above, such a silhouette resembles a pear. A particularly remarkable feature of this fish is its strongly protruding eyes, which are set not on the sides, but on the top of the head. Such a design is necessary so that the organ of vision can remain on the surface of the soil and make an active review of the surrounding water area.
The body of the cow fish is covered with small tan scales, the color on the sides is spotty. The body looks smooth, and the surface of the head is rough, wrinkled and bumpy, equipped with spikes. All stargazer fins have a blue trim, with the exception of the first dorsal, which is completely black.
Distribution area and biotope characterization
The distribution range of cow fish covers the following territories:
- part of the Atlantic Ocean, stretching along the shores of Europe and Africa;
- coastal zone of the Mediterranean, Northern and Black Seas;
- strait of the English Channel;
- Bay of Biscay (very rare here).
The European stargazer lives at shallow depths (from 10 to 50 meters). As a biotope, this fish prefers sandy and dirty bottoms.
Lifestyle & Nutrition
During the hunt, the whole fish burrows itself in the sand, leaving only eyes and mouth on the surface. Frozen in this position, the predator awaits the arrival of the victim. His eyes constantly rotate in different directions, evaluating the proximity of prey. The movement of the fleshy outgrowth of the lower lip serves as a bait.
The diet of sea cow fish includes:
- Worms
- mollusks;
- crustaceans;
- small fish.
The stargazer captures the prey with the help of the lower jaw, armed with tenacious teeth. An animal caught in a wide open mouth is swallowed immediately. Sometimes, before capturing a victim, the stargazer paralyzes it with the help of an electric discharge.
Reproduction and Life Cycle
Cow fish is a dioecious species characterized by a slight sexual dimorphism, expressed in body size. So, female starships are larger and more massive.
Spawning is carried out in the summer. At this time, each female lays about 125 thousand eggs. From the fertilized eggs, fry appear, which for some time lead a pelagic lifestyle, and only then pass to the benthic one.
Puberty in males is achieved after 1 year, and in females after 2 years. The sizes of 11 cm and 14 cm correspond to this age, respectively. The total life expectancy of cow fish is very short (from 4 to 6 years).
Danger to humans
The European stargazer is among the most dangerous representatives of the ichthyofauna of the Black Sea. Cow fish, of course, cannot cause serious irreparable harm to human health, but still a collision with it has very unpleasant consequences.
In the body of a stargazer are poisonous:
- spikes located on the gill cover;
- mucus covering the body;
- fins;
- teeth.
Mucus is harmful when the fish comes in contact with unprotected human skin, resulting in a chemical burn. The poison contained in the spikes, fins and teeth penetrates the body through damage caused by punctures or bites. Such wounds are very painful and are accompanied by the appearance of a large swelling in their place. Toxin entering the bloodstream causes dizziness.
Sea cows are not always poisonous, but only during the spawning season. However, they are dangerous exclusively for fishermen. Ordinary vacationers cannot accidentally meet a European stargazer who lives in a near-bottom zone 10 meters or more from the coast.