Today we are going to talk about pike fishThis fish is called pike because that's what the Polish weapon it resembles was called. It also has other common names, such as great northern pike, grass pike, or crocodile fish (this is because its head is similar to that of a crocodile). Its scientific name is esox lucius and it has quite a few curiosities.
In this article we are going to talk in depth about the pike fish, so if you want Keep reading you just have to do it 
Key features
This fish belongs to the genus EsoxThese fish live in brackish and fresh waters and are able to live in both environments. Their color is olive green and presents yellow shaded speckles and white on the belly. It also has short, light bar-shaped spots on the flank, and some fins can be seen dark spots.
To recognize a younger pike fish, you have to look at its longitudinal yellow stripesA curious thing about this fish is that it no longer has scales on the lower half of its gills. Also, if you look closely at that crocodile-like head, we can see sensory pores distributed throughout the head, especially under the jaw, which help you read your surroundings.
Your body is elongated and almost cylindrical, with the dorsal fin set far back, which facilitates explosive accelerations. lateral line It is well marked and usually has 110-130 small scales. The mouth, shaped like a duck's beak, opens upwards and houses a replaceable dentition: When a tooth is lost, another one located behind it advances and replaces it.
As for size, most pike measure between 50 and 100 cm, although there are specimens that can exceed one meter. Females usually reach larger sizes that males, and the most corpulent specimens, can reach very high weights in optimal conditions.
There is some hybrid forms of pike fish, such as the so-called tiger pike, resulting from the cross between Esox masquinongy y esox luciusIn this type of hybrids, the Males are usually sterile, so they don't generate populations on their own. Occasionally, females are fertile and can interbreed with one of the parent species.
We can also encounter the so-called silver pike fish. It is not a subspecies, but a color mutation observed in more dispersed populations or those subject to particular conditions, which results in a lighter or silverier phenotype.
Behavior of the pike fish
These fish are capable of developing very fast swimming startsThis large acceleration causes small swimming bursts that make their prey fearful with their unpredictable movements.
Not only for hunting do they use this large boot, but also for avoid threatsAlthough they lead a relatively sedentary life, when they detect their prey, They use these bursts to launch and capture it effectively. During hunting, a wave-like movement is common in S-shaped to gain speed and then a gesture in C-shaped to decelerate abruptly.
These bursts are possible because they have a fast digestionBy not having to expend energy on prolonged digestive processes, they are lighter and can execute almost instantaneous bursts of speed. This is how they achieve a high number of catches during the day. They are most active in daylight (especially at dawn and dusk) and tend to be calmer at night.
The pike is a predator solitary and territorial. It spends a lot of time motionless, lurking, camouflaged among vegetation or next to structures such as logs and rocks. It rests on its movement-oriented vision, on the lateral line to detect vibrations and on its keen sense of smell to locate prey even in low visibility. In situations of abundant pike, it may appear cannibalism, a behavior that also helps the population self-regulate.
Habitat and area of ​​distribution
These fish are found in slow-flowing streams and shallow areas. For the pike to exploit its bursting power, the water speed cannot be very high or it would become a difficult resistance to overcome. It also appears in lakes with aquatic plant meadows, in cold, clear waters with rocky or pebble bottoms. Hence its common name of grass pike.
It is usually a predator of emboscada. Hides among structures and plants to assault their prey at its best, conserving energy and remaining motionless for long periods. It can be found in any habitat with body of water and abundant food, provided they exist spawning grounds suitable for shallow waters with dense vegetation.
Cannibalistic behavior is frequently observed, so the pike needs shelters between plants to avoid being preyed upon by fellow creatures when young. It lives mainly in sweet water, although it tolerates brackish waters; for example, it can be seen in the waters of the Baltic Sea in low salinity areas.
The clearer the water, the better. Their dependence on vegetation for hiding and lurking makes turbid waters (with less light and strong currents) less favorable due to the shortage of macrophytes.
The pike is native to much of Europe, Asia and North America. It has spread widely on the Iberian Peninsula, with a notable presence in reservoirs and inland rivers. It is most abundant in numerous inland basins and reservoirs, with well-established populations in different regions (e.g., in Levantine reservoirs, Castilian, Leonese and Extremaduran rivers), while in very Atlantic areas its distribution is smaller.
Where it is not native, its introduction for the deportive fishing has had significant ecological consequences for native fish, amphibians, aquatic reptiles, and even birds. In Spain, it is found classified as an invasive alien species, which is why its introduction into the natural environment is prohibited, as well as its possession, transportation, trafficking and tradeAny fishing activity must comply with current regional and local regulations.
Feeding and hunting techniques
The pike is a opportunistic carnivore. Their diet consists mainly of de peces (including fry of its own species), but also captures amphibians like frogs and toads, crabs and acuatic birds y small mammals that enter the water. The consumption pattern varies with local prey availability.
The most frequent attack strategies are: emboscada (from vegetation cover or structures), the short pursuit starts when the prey flees and, punctually, coordinated actions in high-density areas, taking advantage of the disorder of banks de peces. Combining camouflage, explosive starts and a wide mouth armed with teeth ensures a high success rate in close-range attacks.
Size, growth and longevity
The average size of the pike is between 50 cm and 1 meter, with large specimens that can exceed these figures in very productive environments. Females generally reach greater lengths than males. Growth is rapid during the first years as long as there is abundance of prey and vegetation cover.
Under favorable conditions, pike can live near Two decades, and in exceptional situations reach older ages. The longevity It depends on habitat quality, food availability and fishing pressure, with females typically living longer than males.
Taxonomy and key morphological features
Basic taxonomy: Kingdom Animalia; Phylum Chordata; Class Actinopterygii; Order Esociformes; Family Esocidae; Genus Esox; Species esox luciusIts overall conservation status is Minor concern according to the red list (IUCN), although on a regional scale it can be treated as invasive.
Distinctive features: body hydrodynamic and elongated, wide head, Big Mouth with replaceable teeth arranged in rows, dorsal fin small one located far back that acts as a rudder at high speed, and lateral line sensitive to vibrations. The color varies from olive green to brown with light spots on the flanks and belly light, an effective camouflage in dense vegetation.
Reproduction
These fish choose the spring to reproduce. This may be due to several reasons, including greater availability of prey and a better energy efficiency due to warmer water temperatures.
The pike fish is capable of reaching their sexual maturity from two years of age, although the exact age may vary with latitude, temperature and productivity of the environment; in cold or poor regions it may be delayed for a few more years. It spawns when the water temperature reaches approximately 8-15 ° C, typically in shallow, vegetation-covered waters.
Reproduction is usually polygamous and promiscuous-collective: Several females and males gather in flooded areas or on banks with aquatic plants to spawn. Females are capable of laying eggs. large number of eggs adhesives (tens or hundreds of thousands depending on the size of the female), attached to vegetation. Once the eggs are released by the females, if the water temperature is below 6 °C, viability is drastically reduced and development may stop; in the optimal range, Hatching occurs in 10-14 days, shortening with slightly higher temperatures within the safe range.
The fry measure about one centimeter at birth and begin feeding on zooplanktonAs they grow, they move on to larger and larger prey until they reach a typical carnivorous diet. In environments with lots of vegetation and food, the first year's growth can be remarkable.
Status, ecological impact and conservation
On a global scale, pike is classified as Minor concern due to its wide distribution and resilience. As a top predator in many ecosystems, it plays a regulatory role on forage fish and other prey, helping to maintain trophic balance when it is part of the native assemblage.
In areas where it has been inserted, their presence poses a significant threat to the native biodiversityIn Spain it appears in the Catalogue of invasive alien species, with prohibitions on introduction, possession, transport, trafficking and trade. Management focuses on prevent new releases and minimize impacts on ichthyofauna, amphibians, aquatic reptiles and birds.
Interest in sport fishing and responsible practices
The pike is highly valued in the deportive fishing for its power and spectacular attacks. Among the most common techniques are the spinning with spoons, spinnerbaits, jerkbaits and swimbaits (hard or vinyl) that imitate fish and frogs; the fly fishing with bulky streamers; the use of natural bait (where permitted) and the trolling Light to search for active fish. Due to their teeth, it is essential to use steel basses or high-strength fluorocarbon.
The regulations on minimum sizes, quotas, seen and permitted methods vary by region. It is important to always check the current regulations of the place and respect breeding periods, release copies when advised by law or ethics and do not transfer or release pike in new bodies of water.
How to distinguish it and avoid confusion
To safely identify esox lucius It is worth paying attention to its duckbill mouth, the mottled pattern on the flanks, the rearward dorsal fin and the elongated body. Females are usually more voluminous and larger. In areas where other species of squids coexist, the pattern of spots and the shape of the head help to differentiate it. Other European freshwater predatory species such as the Sander zander (pikeperch or sandra) present different morphology and dentition, which avoids confusion when paying attention to these features.
I hope with this insights can get to know the pike fish better.
The pike is an emblematic predator of temperate waters with fascinating biology, capable of thriving in a wide variety of habitats and endowed with highly effective hunting behaviors. Understanding its ecology, reproduction, distribution and impact allows you to enjoy its observation and fishing in an informed manner, while promoting responsible practices and the care of aquatic ecosystems.