The spottail stickleback is a small, little-known fish that inhabits the salt and brackish waters of Quebec. Although it is not a primary target for sport fishing, it plays an essential role in the aquatic ecosystem by serving as prey for several more sought-after fish species. It is mainly found in estuaries and coastal areas, where it feeds on small invertebrates. Its ability to tolerate slightly polluted waters makes it an interesting ecological indicator. It is a fun fish to observe, especially during the breeding season when the male takes on bright colors to attract the female.

The spottail stickleback has a small, elongated body, typically not exceeding 5 to 7 cm in length. Its base color is often silver, sprinkled with dark spots that give it its name. The fins are generally transparent, with silver reflections. It has a series of small spines on its back, characteristic of the stickleback family. The mouth is small and slightly turned upward, indicating its diet based on small invertebrates. Scales are absent, but the skin is covered with bony plates. During the breeding period, the male is distinguished by a reddish belly and more colorful flanks to attract the female.

In Quebec, the spottail stickleback is primarily found in estuaries and bays along the St. Lawrence River. It is particularly abundant in areas where freshwater meets saltwater, such as in salt marshes and coastal lagoons. It is also found in certain areas of the Gulf of St. Lawrence. Although it is widely distributed, it often goes unnoticed due to its small size and lack of commercial interest.

The spottail stickleback prefers brackish and shallow waters, often near shorelines where currents are weak. It is frequently observed in estuaries, salt marshes, and coastal lagoons. This species is particularly adaptable and can tolerate a wide range of salinities, allowing it to thrive in various habitats. Areas with abundant aquatic vegetation or floating debris provide shelter and ideal breeding sites. In general, it prefers waters with temperatures between 10 and 15 °C.

The reproduction of the spottail stickleback occurs in spring, when the water temperature begins to rise. The male builds a tunnel-shaped nest from aquatic vegetation and debris, which he maintains with a sticky substance secreted by his kidneys. Once the nest is complete, he attracts a female with his bright colors. After spawning, the male guards the nest and ventilates the eggs until they hatch. The young hatch after about a week and quickly begin to feed on plankton. The stickleback reaches sexual maturity in 1 to 2 years and can live up to 4 years. Spring → Spawning and nesting → Summer → Growth of young → Fall → Preparation for winter → Winter → Survival in colder waters.

The spottail stickleback is generally social, forming small schools to protect themselves from predators. It is territorial during the breeding season, particularly the males who vigorously defend their nests. This fish is relatively tolerant of environmental disturbances, but it prefers calm and undisturbed waters. Sticklebacks are more active during the day when light facilitates foraging. They are not very responsive to noise, but sudden changes in atmospheric pressure can influence their behavior.

The diet of the spottail stickleback varies with age. Fry primarily feed on phytoplankton and small zooplankton. As they grow, adults consume a wider variety of prey, including small crustaceans, insect larvae, and aquatic worms. In summer, when food resources are abundant, their food intake increases. In winter, their metabolism slows down and they feed less frequently.

In spring, the spottail stickleback is more active, especially during spawning. It is often close to shores in shallow areas. In summer, it stays in waters with abundant vegetation, enjoying warmer temperatures. Fall sees a decrease in activity as the water cools, and it retreats to deeper, more protected waters. In winter, its activity is reduced, but it can still be observed in unfrozen waters. Cloudy or slightly rainy days are ideal for observation, as it is less visible to predators.

Although the spottail stickleback is not a target for lure fishing, its movements can attract other predators. If you’re looking to mimic its appearance to target larger fish, opt for silver lures with dark spots. In clear waters, a metallic shine can be effective, while in murky waters, lures with red or green reflections may better capture attention.

To observe or capture the spottail stickleback, a light rod of 1.80 m with a fast action is sufficient. A light reel with a 2 to 4 lb line is adequate. Small hooks (size 10 to 12) are recommended to avoid injuring these small fish. A fluorocarbon leader can help make the presentation more discreet.

If you capture a spottail stickleback, handle it carefully to avoid damaging it. Use wet hands or a damp cloth to avoid harming its delicate skin. For release, ensure it is properly oriented and can swim freely before letting it go. For photos, avoid keeping it out of the water for too long.

The main predators of the spottail stickleback include larger fish such as pike and striped bass. Aquatic birds such as herons and cormorants also feed on these small fish. Young sticklebacks are particularly vulnerable to amphibians like frogs.

The spottail stickleback is not considered an endangered species in Quebec. It benefits from good resilience due to its ability to adapt to different environments. However, water quality and the destruction of coastal habitats remain concerns. There is no specific regulation on its fishing, but it is always advisable to practice catch and release to preserve local populations.