Round goby

Round Goby

A large Neogobius melanostomus

The round goby (Neogobius melanostomus) is a small, bottom-dwelling fish native to the Black Sea and Caspian Sea regions. It has become an invasive species in many parts of Europe and North America, particularly in the Great Lakes and the Baltic Sea.

Description

The round goby is characterized by its robust body, which can grow up to 25 cm in length, though most individuals are smaller. It has a distinctive black spot on the first dorsal fin and a fused pelvic fin that forms a suction cup, allowing it to adhere to rocks and other surfaces. The coloration of the round goby is typically mottled brown and gray, providing camouflage against the substrate.

Habitat

Round gobies are benthic fish, meaning they live on the bottom of water bodies. They prefer rocky and sandy substrates where they can find shelter and food. In their native range, they inhabit coastal waters, estuaries, and rivers. In invaded areas, they have adapted to a variety of habitats, including lakes, rivers, and even brackish waters.

Diet

Round goby eggs

The diet of the round goby is diverse, consisting mainly of benthic invertebrates such as mollusks, crustaceans, and insect larvae. They are also known to consume the eggs and fry of other fish species, which has significant implications for the ecosystems they invade. Their ability to feed on zebra and quagga mussels has allowed them to thrive in the Great Lakes.

Reproduction

Round gobies have a high reproductive capacity, with females capable of spawning several times during the breeding season, which lasts from April to September. They lay their eggs in nests created under rocks or other submerged objects, which are then guarded by the male until they hatch. This reproductive strategy contributes to their success as an invasive species.

Impact as an Invasive Species

The introduction of the round goby to non-native regions has led to significant ecological changes. In the Great Lakes, they have outcompeted native fish species for food and habitat, leading to declines in native populations. Their predation on the eggs and young of native fish further exacerbates these impacts. Additionally, their presence has altered the food web dynamics, affecting both prey and predator species.

Control and Management

Efforts to control round goby populations include physical removal, habitat modification, and public education to prevent their spread. However, their high reproductive rate and adaptability make them difficult to eradicate once established. Research into biological control methods is ongoing, with the aim of finding sustainable solutions to manage their populations.

Related Pages

• Invasive species
• Great Lakes
• Benthic zone
• Zebra mussel

Neogobius melanostomus