- Overfishing: Perch are a popular commercial and recreational fish in Lake Erie, and overfishing has been a major factor in their decline. In the past, perch were heavily targeted by commercial fishermen, and recreational anglers also took large numbers of fish. This led to a decrease in the population size and reproductive capacity of perch.
- Predation: Perch are preyed upon by many species of fish, including walleye and smallmouth bass, which are both native to Lake Erie. As these predator populations have increased, they have put additional pressure on the already-depleted perch population.
- Habitat loss: Changes in the physical and biological environment of Lake Erie, such as the introduction of non-native species and the loss of important habitat features like submerged vegetation, have affected the distribution and abundance of perch. The loss of wetland habitats, which are important for spawning and juvenile survival, has also had a negative impact on perch populations.
- Pollution: Lake Erie has a history of pollution from industrial and agricultural sources, which has led to water quality problems like eutrophication and harmful algal blooms. These conditions can lead to low oxygen levels in the water, which can stress and kill fish.
- Climate change: Changes in water temperature and other climate-related factors have also been linked to the decline of perch populations in Lake Erie. Warmer water temperatures can reduce the availability of suitable habitat and food sources, while extreme weather events like storms and flooding can disrupt spawning and other important life stages for perch.
- Cormoran birds: Studies have confirmed that these birds can eat one to one-and-a-half pounds of fish per bird per day, and yes they love to eat perch! These birds (that act like a duck and a bird) are having a signifigant impact on the continued decline of perch.
Overall, the depletion of perch in Lake Erie is likely due to a combination of these and other factors. Efforts to restore the health of the lake and its fish populations will require a comprehensive approach that addresses multiple stressors simultaneously. This could include measures to reduce overfishing, opening a hunting limit to reduce the number of cormorans, restore important habitats, and improve water quality, and ecosystem health.
