Grass Pickerel (Esox americanus vermiculatus)

The Grass Pickerel is a small member of the Pike family, usually growing less than 30 centimeters in length and 500 grams in weight. Like other Pike, the Grass Pickerel has a long, cylindrical body, long snout, forked tail, and dorsal and anal fins located well back on the body. Characteristics specific to the Grass Pickerel include: dusky to yellow-green fins, multiple dark, wavy vertical bars along the body, and the presence of a dark bar extending below each eye on adult fish.

The Grass Pickerel reaches sexual maturity by two years of age, with spawning occurring in the spring months from late March to early May, but in rare cases during late summer and winter. Spring spawning is associated with flooded terrestrial vegetation at temperatures ranging from 4 – 12° C. No nest is built and no parental care is provided for the eggs or young, as they are simply dispersed in the water column and adhere to aquatic vegetation. The lifespan of the Grass Pickerel is seven years or less.

This species is typically found in slow, warm, shallow waterways with abundant aquatic vegetation present. These conditions often result in tea-coloured water, due to abundant dissolving organic matter. In riverine areas, juvenile Grass Pickerel have been associated with shallow water and silt/clay substrate and vegetation. The species has been found in multiple tributaries on the east shore of Lake St. Clair, including the East Sydenham River in 2003. It is possible that the Grass Pickerel utilizes these tributaries to spawn while flooding occurs, as the physiography of the area is dominated by clay and till substrate. Threats include habitat destruction and degradation, such as loss of wetland habitat, as well as sediment and nutrient loading, contaminant inputs, and exotic species.

grass pickerel