In June 2020, a news story broke regarding a photo of a large creature taken in the waters of Lake Michigan, with some speculating it could be a shark.
The speculation quickly spread, leading to a flurry of shocked comments, most asking whether it was indeed a shark found in the lake. Some suggested that the photo was a fake, with others wondering if Lake Michigan had a resident shark population.
The specimen featured in the photo has been identified as a Bull Shark, an apex predator which is known to foray into fresh waters far from the sea. These long journeys can span over 6,000 miles through the Mississippi River, giving rise to the question of whether these sharks could survive and even establish a population in the waters of Lake Michigan.
In the following days, experts from the Natural History Museum and the Michigan Department of Environment, Great Lakes and Energy were contacted.
Dr. Jeffrey Kneebone, a foremost marine biologist with the Natural History Museum, told the press that while a Bull Shark’s presence is not possible, other species of sharks such as the Spiny Dogfish, Skate and Smooth Dogfish are all living in areas where Lake Michigan and surrounding waters meet the sea – adding that any such sightings should be considered very rare, though it is still something natural and not necessarily cause for alarm.
Highly skilled fishermen, anglers and hunters have both reported as well as captured a variety of shark species in the Freshwater Basin. One such angler, whose mother worked at a local museum, shared that her mother had acquired specimens of sharks that were caught in the early 2000s in it’s waters. According to one report, the museums would send some of the more interesting specimens to the University of Michigan so they could be examined and logged.
It appears that some species of sharks may be able to survive in freshwater environments, such as the Bull Shark. However, it likely cannot survive in waters such as Lake Michigan without some kind of saltwater source near by, such as an estuary. Even then, the odds that a shark could maintain a resident population and survive for extended periods of time in a lake are low, as sharks require a specific type of environment and food source to survive.
What About Other Sea Creatures?
Recent evidence suggests that some other sea creatures are making their home closer to shore, such as pufferfish, sole, cutthroat trout and whale sharks. These creatures either have a wide range of salinity tolerance, or have adapted to their environment by finding specific areas of salty water nearby or established by man made outlets, such as the Wisconsis River.
Whilst researchers have yet to fully investigate how these creatures have managed to appear closer to shore, it is likely that they are finding their own way into the lake by following food sources, or swimming up rivers. This has helped improve a more general understanding of how marine life can survive in habitat far from their usual environments.
What Significance Has This Had?
The speculation around the Lake Michigan Shark has been a major talking point in the global marine biology community. This matter of the mysterious shark has prompted further research into strange sightings, which has enriched the understanding of marine life’s migratory means, or the diversification of species able to live in otherwise unusual habitats.
The intrigue of the Lake Michigan Shark has also heightened public awareness of shark populations. This has been especially useful for conservation efforts, as the media coverage has secured much attention needed to advocate the protection of fragile shark ecosystems.
This heightened awareness has also led to changes in legislation aimed at protecting sharks and the aquatic environment — with initiatives like the US Shark Conservation Act of 2011, which forbids the removal of shark fins from the sea, has seen a surge in popular support.
Conclusion: Sharks in Freshwater Ecosystems
The Lake Michigan Shark, and other sightings of sharks in freshwater habitats suggests that it is possible for shark species to survive and even establish populations in places where their survival had previously been thought impossible.
Fishermen, anglers and hunters may still seek to catch sharks, whether for preservation or sport — but achieving the delicate balance between fishing and conservation is essential for protecting the creatures, as well as humans. To this end, developments in legislation and growing awareness of the impacts of fishing can pave the way for a more sustainable era of shark conservation.
Agricultural Implication
The presence of shark sightings in freshwater environments has also sent shockwaves through the agricultural community — with experts warning that the presence of these apex predators could pose a threat to local farms.
Research has suggested that Bull Sharks could attack livestock, such as pigs and ducks, in coastal rivers in Florida. However, the impact of similar events elsewhere is still not known and this will require further study.
Moreover, shark species that tend to hover near the surface for extended periods of time could put fishermen and recreational boaters in danger. Although shark-borne attacks are highly uncommon, the waters of Lake Michigan have never been as densely populated as they are now — creating a potential for harm if sharks become a conventional hazard in the lake.
Environmental Impact
Sharks are natural predators and play an important role in maintaining the balance of aquatic ecosystems. A decline in shark populations due to unsustainable fishing practices, for instance, could easily tip the scales in favor of competitors and lead to an overall decrease in ecosystem health.
The presence of sharks in a freshwater habitat would only help safeguard the lake’s ecosystem since sharks require healthy and balanced aquatic living conditions in order to survive.
Sharks act as a major supplier of important nutrients in the food chain, where their prey is consumed by other species. This role can help support other fish, animals and birds in the area, which would in turn bolster the lake’s resources.
Future Developments
With the presence of sharks in Lake Michigan, the focus turns to the development of long-term strategies for preserving ecosystems and ensuring public safety along with it. Although the speculation continues over the true cause behind recent shark sightings, communities have united to safeguard the lake from overfishing and damage from environmental pollutants.
Despite the uncertainty of the future, the one positive development from all of this has been an increase in local environmental engagement and the development of conservation regulations.
This has sparked a greater public interest for both shark-protection and water safety that can help shape the development of the aquatic environment further. Local councils and organisations have been developing new initiatives, such as eco-tourism sites, in order to secure the future of the lake and the species dependent on it.
