ESOX LUCIUS (PIKE)

Contents hide

1) Introduction

2) Classification of Esox lucius (Pike)

3) Geographical distribution

4) Habit and habitat

5) General Characteristics

6) Ecological Importance

7) Conservation Status

8) Special features

9) Identification

Introduction

The northern pike (Esox lucius), commonly known as pike, is a predatory fish native to freshwater bodies across the Northern Hemisphere, including North America, Europe, and parts of Asia. Recognizable by its elongated body, sharp teeth, and distinctive coloration, the pike is both a valued game fish and a significant ecological player in aquatic ecosystems.

Classification of Esox lucius (Pike)

Phylum :- Chordata (Dorsal tubular nerve cord, notochord and gill-slits present.)
Group :- Craniata (Cranium with brain present.)
Sub phylum :- Vertebrata (Vertebral column present.)
Division :- Gnathostomata (Jaws and paired appendages present.)
Super Class :- Pisces (Paired fins, gills and skin with scales.)
Class :- Osteichthyes (Bony fishes. Skin contains dermal scales. Paired lateral fins present. Gills, air bladder present. Cleavage meroblastic.)
Sub-Class :- Actinopterygii (Modern fishes. Vertebrae amphicoelous. Caudal fin homocercal, Scales cycloid or ctenoid. Nostrils do not communicate with mouth cavity.
Order :- Haplomi (Fins with soft rays. Pelvic fin abdominal. Air bladder communicates with pharynx.)
Family :- Esocidae
Genus :- Esox
Species :- lucius

Geographical distribution

Esox is abundantly found in Europe, Northern Asia and U.S.A.-Arkansas and Minnesota eastward and Eurasia. Jurassic to Recent. The fossils are known as early as the Oligocene in Europe.

Habit and habitat

Esox is a marine fish, carnivorous, predacious and noted for their voracity.

General Characteristics

Commonly called as pike, measures 3 meters in length and weight 45 kgs.
Body elongated, divided into head, trunk and tail. Head produced into snout. Head contains eye nostril and mouth.
Mouth large and margin of upper jaw formed by premaxillaries and toothless maxillaries.
Branchiostegal rays 10 to 20; nasal present; vertebrae 43 to 67.
Supra-occipital is in contact with the frontals.
Opercular bone is well developed. Infra-orbital canal with eight or more pores.
Single dorsal fin and anal fins near tail end. Tail contains caudal fin.
Pectoral fins inserted very low pelvic fins between pectoral and anal fins.

Ecological Importance

Apex Predator: Pike occupy a top position in the food web, regulating populations of smaller fish and maintaining ecological balance. Their predation helps control species that might otherwise become overabundant, ensuring biodiversity within their habitats.
Influence on Fish Communities: By preying on various fish species, pike can shape the community structure of freshwater ecosystems, affecting the abundance and distribution of other aquatic organisms.

Conservation Status

According to the IUCN Red List, the northern pike is classified as a species of “Least Concern,” indicating a stable and widespread population. However, local declines have been observed due to factors such as habitat degradation, overfishing, and pollution. Conservation efforts focus on habitat preservation, sustainable fishing practices, and monitoring of populations to prevent significant declines

Special features

Pyloric caeca absent. These slender bodied fishes are with large mouths and conspicuous teeth. Some forms grow upto 2.5 m and over 50 kg forming choice game fish.
Ambush Predation: Pike are renowned for their ambush hunting strategy. They remain motionless, camouflaged among aquatic vegetation, and use their acute vision to detect prey, striking with remarkable speed.
Physical Adaptations: Their elongated, torpedo-shaped bodies and posteriorly positioned dorsal and anal fins enable rapid acceleration, making them efficient predators. Additionally, their mouths are equipped with numerous sharp teeth designed to grasp and hold onto slippery prey.
Reproductive Strategy: Pike spawn in shallow, vegetated areas during spring. Females can produce a large number of eggs, contributing to their resilience in various environments.