Goby Fish: Invasive Species in the Great Lakes

Kiara Vallier | August 2nd, 2016

Invasive marine species are a significant problem in North America's Great Lakes and many other major bodies of water around the globe; goby fish are just adding to that problem. In a past blog post, we explored the liabilities of foreign species entering new water environments and how they disrupt existing, long established ecosystems. We focused on Zebra Mussels (an invasive species not native to the Great Lakes which are abundantly thriving there) and explored some of the major issues created by the proliferation of non-indigenous species.

What is an invasive species?

Invasive species are considered to be a plant, fungus, or animal "species that is not native to a specific location (an introduced species), and that has a tendency to spread to a degree believed to cause damage to the environment, human economy or human health.”
https://en.wikipedia.org/wiki/Invasive_species

goby fish gobiidae neogobius melanostomus — Gobiidae
Neogobius melanostomus

Today, we are going to focus on an aquatic species that has become extremely common throughout North America's Great Lakes: goby fish. There are over 2000 different variations of this species, originating from the family Phylum Gobiidae. One of the most notable features of the goby fish is a sucker used to hold onto rocks and coral.

Why Are Goby Fish Invasive?

We have encountered this species many times during expeditions in the Great Lakes: exploring shipwrecks in Lake Huron, diving in the waters of Lake Ontario, holding search and rescue demos in Lake Erie, and venturing through the surf on Lake Michigan. Often, as we pilot a Deep Trekker ROV close to the lake bed or attempt to pick something up with the grabber, goby fish will inevitably be found swimming nearby.

Goby fish are native to rivers and estuaries of the Black and Caspian sea basins. While these seemingly tiny creatures appear harmless, the growing goby fish population is a major concern for the health of the Great Lakes. They were first identified in North America in the late 1980's; found in the St. Clair River, just north of Windsor. Goby fish have since rapidly spread among the other lakes.

Learn how ROVs can aid in species observation for your aquatic research

Threats of an invasive species

The primary ecological liability associated with goby fish in the Great Lakes is competition for food and habitat among the native fish. This is the largest issue with advancing invasive species as they initially disturb, disrupt, and threaten to destroy established healthy ecosystems.

This competition for food and habitat real estate are having a negative impact on the Great Lakes. Their migration, combined with the inadvertent introduction of other non-native species, bring great concern in both environmental and economic points of view. Zebra mussels also pose tremendous challenges among the ecological communities residing within the lakes and are viewed as much more of an issue than the goby fish. Certain species of goby fish actually feed on other invasive species, like Zebra mussels, and ironically help reduce their impact.

Minor pressure or significant impact

It can be surmised that goby infestations apply some pressure to other species; they compete for food and habitat which cause them to grow stronger and more abundant. At this point in time, goby fish may not be the prime invasive threat to the Great Lakes. However, without monitoring and sustained attempts at containment and elimination from the Great Lakes, every invasive species undoubtedly has a growing negative impact on these waters.

Check this out

Still not sure what a goby fish looks like? Check out our footage of the gobies around these lakes. Keep in mind they can blend in with their surroundings. So we made a little game. Can you can spot the goby?