Poisonous fish on the planet much more than poisonous snakes – more than 1250 species (snakes – 410). And every year ichthyologists discover new dangerous species. In this article we are not talking about the exotic inhabitants of the tropical seas, and about ordinary Russian fish living in our rivers. That’s only when you try to use this trivial-looking production in food from fisherman might suddenly begin diarrhea, headache, hallucinations, and other troubles, including death.
Easy Russian fish
Let us first clarify what classes can be divided poisonous fish. So, they are primary and secondary toxic-poisonous. What does it mean? That means there are fish, like snakes produce venom in special glands or by its nature containing in the body dangerous products of metabolism, that is, initially-poisonous.
To secondary poisonous fish are able to accumulate in their bodies a poison contained in the environment. Such environments can be living in the pond poisonous algae or, even worse, fall into the water of toxic human waste.
And if the second paragraph is all clear, and to protect yourself from poisoning very easily (just not enough to catch and certainly not to eat fish caught in suspicious ponds), initially-poisonous things are much more complicated. We begin our story. Continue reading
The history of breeding goldfish Asia has at least a Millennium and originated from children’s hobby to collecting. in which the housing was offered and developed in cages. in the paddocks. in the wells. in tubs and barrels for all small and medium animals — as the first kind of Pets at home .
In China and Korea over a thousand years ago was engaged in not only fishing. but breeding and raising goldfish. Over the years of breeding the Chinese fish farmers. appeared and established natural mutations with drastic changes in body shape and fin structure. eyes. the structure of the skin and staining fish were obtained decorative forms and color variations, which became the core of most of today’s known species.
The first written mention of the Golden fish with red scales came from China during the reign of the Qing dynasty ( 265 -420 ad ). In those days, these fish were seen in one of the lakes of mount Lushan. the area of the river the City is near the modern province of Shaanxi. which flows to the South China and Northern Vietnam.  In the ancient Chinese treatise Shan Hai Jing. presumably written in the late centuries BC — the beginning of our, there is also a record of the “red carp”. However, there is absolutely no certainty that these wild representatives were the ancestors of segodnyashnaya fish. It is assumed that the red coloration was obtained as a result of purposeful breeding work first pet lovers and falls on the reign of the Tang dynasty ( 618 -907 year of a new era ). 
It is possible that the appearance of unusual forms and colors of goldfish had a direct influence of the religious community professing Buddhism. manifestation of pity and humanity to the poor, while maintaining the ugly offspring of pond fish in specially equipped farms and dams, and then in specially created containers and decorative vessels; not taking them for food. Continue reading
Reproduction and spawning
Reproductive behavior of tropical marine fishes is poorly documented because only a few species breed in captivity. However, some – such as clowns, gobies and seahorses to breed relatively simple. Others, like coral fish may spawn in the aquarium but the fry are so immature that they are very difficult to grow.
To ensure availability in the aquarium at least one opposite-sex pairs marine fish breeding is almost impossible, because in most species males and females are externally indistinguishable just. However, if you keep the fish in the pack, their behavior will help you to determine the sex charges. If two identical fish fight is most likely male contesting territorial rights. If two fish are related to each other friendly, it can be compatible in a female and male. Unusual swimming movements or postures may not be indicative of flirting – so, in your aquarium just got a couple. In the mating season sometimes appear insignificant physical differences: the female has, of course, the belly is inflated from the calves. Males often intensifies the color, and the picture loses clarity. Some species are able to change their gender, what does not prevent, but rather contributes to the search for a pair for spawning. For example, all multiclone – males, but if you have a small group (two individuals), the dominant fish will become the female and will mate with the nearest dominant male. Kood I-frames and some coral sex change occurs in the opposite direction: the dominant individual in a purely female group turns into a male. Continue reading