Esox

Esox is a genus of freshwater fish, the only living genus in the family Esocidae — the esocids which were endemic to North America,Europe and Eurasia during the Paleogene through present.

The type species is E. lucius, the northern pike. The species of this genus are known as pike and pickerel, and in heraldry they are usually called lucy.

The big pike species are native to the Palearctic and Nearctic ecozones, ranging across northern North America and from Western Europe to Siberia in Eurasia. They have been found in many urban lakes in Western Europe, reported to be in the Rostrum (Lucerne) and the Serpentine, (London).

Pike can grow to a maximum recorded length of 1.83 metres (6 ft 0 in), reaching a maximum recorded weight of 35 kilograms (77 lb). The UK record pike of 21 kilograms (46 lb) was caught on a Creek Chub Pikie lure by Roy Lewis at Llandegfedd Reservoir in Wales in 1992. Individuals have been reported to reach 30 years in age. All pike over 5 kilograms (11 lb) in body weight are females. They have the elongated, torpedo-like form of predatory fishes, with sharply-pointed heads and sharp teeth. Their coloration is typically grey-green with a mottled or spotted appearance with stripes along their back, perfectly camouflaged among weeds. Individual pike marking patterns are unique, like fingerprints.

Esox eat fish

Walleye (Sander vitreus, formerly Stizostedion vitreum) is a freshwater perciform fish native to most of Canada and to the northern United States. It is a North American close relative of the European pikeperch. The walleye is sometimes also called the yellow walleye to distinguish it from the blue walleye, which is an extinct subspecies formerly found in the southern Great Lakes.

In some parts of its range, the walleye is known as the colored pike, yellow pike or pickerel (esp. in English-speaking Canada), although the fish is related neither to the pikes nor to the other pickerels, both of which are members of the family Esocidae.

Genetically, walleyes show a fair amount of variation across watersheds. In general, fish within a watershed are quite similar and are genetically distinct from those of nearby watersheds. The species has been artificially propagated for over a century and has been planted on top of existing populations or introduced into waters naturally devoid of the species, sometimes reducing the overall genetic distinctiveness of populations.

The common name, "walleye", comes from the fact that their eyes, like those of lions, reflect white light. This "eyeshine" is the result of a light-gathering layer in the eyes called thetapetum lucidum, which allows the fish to see well in low-light conditions. In fact, many anglers look for walleyes at night since this is when major feeding patterns occur. The fishes' eyes also allow them to see well in turbid waters (stained or rough, breaking waters), which gives them an advantage over their prey. Thus, walleye anglers will commonly look for days and locations where there is a good "walleye chop" (i.e., rough water). This excellent vision also allows the fish to populate the deeper regions in a lake, and they can often be found in deeper water, particularly during the warmest part of the summer.

Walleyes get their name from their huge marble like eyes, which feature a layer of reflective pigment. This gives the fish a distinctively walleyed look, but it also means that the walleye can see quite well in dim light. The most common prey of the walleye, the yellow perch, lacks this ability to see well in low light, so it is easy to see why the walleye has been such a successful predator. This well developed night vision also means that walleyes do a great deal of their feeding after dark.

Because their eyes are so sensitive to light, walleyes do not tolerate bright sunlight well. If they are swimming in clear water on a sunny day, walleyes are likely to go as deep as forty feet to avoid the harshest rays of sunlight.

Walleyes are not totally color blind, but they do lack the blue/yellow cells. For this reason, scientists believe that walleyes perceive the world entirely in shades of green and red. This means walleyes can see lures that are red, orange or green more readily than lures of other colors. It is important for the fisherman to realize, however, that the depth and clarity of the water can affect how the fish perceives the color. For this reason, many anglers will alter the color of their lures based on the depth of the water.

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Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate (or craniate) animals that lacks limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups.

Movie

Рибе (lat. Pisces) су ектотермни водени kicmenjaci. Постоји преко 27.000 vrsta риба, што их чини највећом групом кичмењака. За кретање им служе парна и непарна peraja. Дишу skrgama, а srce им има једну преткомору и једну комору и кроз њега протиче редукована krv. Немају мали крвоток. Најразвијенији део mozga је мали мозак. Кичменица образована и може бити хрскавичава или окоштала. Оплођење је спољашње, а врсте на основу доношења младих могу бити овипарне, ововивипарне и вивипарне.

Sve ribe sveta