Latest news with #AaronSwitzer
Yahoo
17-03-2025
- Climate
- Yahoo
DNR: ‘Normal' winter could lead to more fish kills during spring thaw
GRAND RAPIDS, Mich. (WOOD) — There are some pros and cons to spring. It is often rainy and muddy and snow can still sneak out of nowhere to steal away the sunshine. The Michigan Department of Natural Resources is warning people of another natural, yet unsavory part of spring: . Unlike recent ones, the DNR says Michigan had a 'more normal' winter this year — 'more cold days and near-average snow fall across the state.' Because of that, you may notice more dead fish than usual. EGLE: Massive Ionia fish kill caused by bad fertilizer application 'Winterkill is the most common type of fish kill,' DNR Fish Production Program manager Aaron Switzer . 'It can be particularly common in shallow lakes, ponds, streams and canals during seasonal changes. It's a natural phenomenon, and these kills are localized. They typically do not affect the overall health of fish populations or fishing quality.' Nutrient runoff and excess road pollution can lead to more fish kills in urban areas, especially after large storms. Shallow lakes with soft bottoms are also more prone to winterkills, especially when deep snowpack reduces sunlight for the lake's plants. 'Fish and all forms of aquatic life need dissolved oxygen to survive,' the DNR says. 'When ice and snow cover reduce the daylight that reaches the water depths, aquatic plants stop producing oxygen, and many die. DNR set to collect walleye eggs near Croton Dam 'Bacteria use the remaining oxygen in the water to decompose the dead plants and other organic materials on the lake bottom. With available oxygen reduced, more aquatic animals die and start to break down, speeding up the rate that oxygen is used for decomposition.' The fish kills may not necessarily happen in the spring, but older ones often aren't discovered until the spring. DNR forced to kill 31,000 salmon after bacterial outbreak at hatchery 'If you see dead fish as a result of winterkill, the fish may appear fuzzy. This is because of secondary infection by fungus, but the fungus was not the cause of death,' Switzer said. Residents can report fish kills to the DNR through the agency's website. If you suspect a fish kill is due to nonnatural causes, call the nearest DNR office. Copyright 2025 Nexstar Media, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.
Yahoo
17-03-2025
- Climate
- Yahoo
DNR: Don't be alarmed if you see dead fish in Michigan lakes this spring
The Brief It's common to see dead fish near bodies of water in Michigan in the spring. Winterkill is most common in shallow bodies of water. Those concerned about dead fish should contact the Department of Natural Resources. (FOX 2) - Seeing dead fish around Michigan lakes as the weather warms? Don't be alarmed. According to the Department of Natural Resources, these fish kills are common in the spring, and more dead fish may be seen this year since there were more cold days and near-average snowfall compared to recent winters. What they're saying "Winterkill is the most common type of fish kill," said Aaron Switzer, DNR Fish Production Program manager. "It can be particularly common in shallow lakes, ponds, streams and canals during seasonal changes. It's a natural phenomenon, and these kills are localized. They typically do not affect the overall health of fish populations or fishing quality." Fish can become easily stressed in winter due to low energy reserves due to minimum feedings, and temperature swings that make handling oxygen more difficult. The creatures seen in the spring may have died in late winter but are not obvious until the ice is gone. Shallow lakes with excess aquatic vegetation and soft bottoms are more prone to this problem, especially when there is a deep snowpack that reduced sunlight for the plants. "If you see dead fish as a result of winterkill, the fish may appear fuzzy. This is because of secondary infection by fungus, but the fungus was not the cause of death," said Switzer. "The fish actually suffocated from a lack of dissolved oxygen from decaying plants and dead aquatic animals under the ice." Though these kills are common, if you are concerned about dead fish, report it to the DNR here, or call the nearest DNR office or Michigan's Pollution Emergency Alert System at 800-292-4706. The Source Information from a Michigan Department of Natural Resources press release was used to report this story.
CBS News
17-03-2025
- Climate
- CBS News
Spring thaw unveils signs of winterkill among Michigan's fish, aquatic wildlife
If you see dead fish and aquatic animals in ponds, streams and canals as the spring thaw settles in, you might have noticed a natural effect called winterkill. "While such sights can be startling, the Department of Natural Resources reminds everyone that it is normal for winter conditions to cause some mortality of fish and other creatures such as turtles, frogs, toads and crayfish," the Michigan DNR office explained in an announcement issued Monday. One of the places where winterkill was noticed lately is in the city of Lapeer in Michigan's Thumb Area. City officials reported Monday they had received several calls about dead fish in Rowden Park, which is the city's largest public park. "Apparently, it's a totally normal early spring event," Lapeer officials said in their social media post, citing DNR as their source. "Winterkill is the most common type of fish kill," said Aaron Switzer, DNR Fish Production Program manager. "It can be particularly common in shallow lakes, ponds, streams and canals during seasonal changes. It's a natural phenomenon, and these kills are localized. They typically do not affect the overall health of fish populations or fishing quality." Fish can become easily stressed in winter, when feeding opportunities are lower, the DNR explained. With the low energy levels, they are less able to handle low oxygen levels caused by decaying plants and organic material. Ice and snow covering water further reduces the daylight available to the water plants, and the cycle continues. Basically, the fish suffocate from lack of oxygen in the water during winter. While that can happen over a period of weeks of months, dead fish might not be noticed until lake ice thaws and breaks. Should you wish to report a fish kill site in the wild, go to If you suspect a fish kill is due to non-natural causes, you can call the nearest DNR office or Michigan's Pollution Emergency Alert System at 800-292-4706.
