End-of-summer means more fish kills statewide

The end of the summer is when fish are most vulnerable to changes in their environment, so even a small amount of pollution can cause major fish kills in Iowa’s waterways. (flickr/AgriLife Today)

The state Department of Natural Resources warns Iowans to consider how fish are affected when using chemicals and fertilizers.

The end of the summer is when fish are most vulnerable — temperatures are high, and dying and decaying plant life reduce dissolved oxygen in the water. Fish and other aquatic wildlife are stressed, meaning pollution can lead to more fish kills.

In 2016, the DNR reported 15 fish kills, 11 of which occurred in the latter part of the summer, after July 15. In the last two weeks, the DNR has investigated four fish kills around the state.

The DNR reminds farmers and homeowners that what they put on their fields or lawns will wash into waterways, where it could harm wildlife. Even a small amount of a chemical can cause serious damage.

“We have received several reports of small summer fish kills at many lakes, ponds, and a few streams throughout Iowa,” said Chris Larson, fisheries supervisor for the DNR in southwest Iowa, in a press release. “We have also had some fish kills caused by pollutants.”

Rarely, however, will all of the fish in a single body of water die at once. Usually the ecosystem can bounce back from a fish kill and balance its population again within a few years.

Farmers and homeowners can prevent pollution-caused fish kills by not applying chemical fertilizer or manure before it rains, and following disposal instructions on pesticide labels.

Spawning stress fish kill in Tama County

More than 1,000 black crappies were reported dead at Lake Casey yesterday due to spawning stress. (Georgia Aquarium
Jenna Ladd |June 8, 2017

A fish kill has been reported at Casey Lake in Tama County. More than 1,000 black crappies were reported dead at the Hickory Hills Park Lake yesterday. Crappies are a North American freshwater sunfish that are indigenous to Iowa. Fish kills can be caused a number of factors including pesticide contamination, high temperatures, algal blooms and more.

“When we get calls about one species of dead fish during the spawning season, it is usually caused by spawning stress,” said Dan Kirby, fisheries management biologist for the Iowa Department of Natural Resources (DNR). Like many freshwater fish, crappies move closer to the shoreline to spawn in the late spring and early summer. Spawning activities require fish to expend a lot of energy, leaving them susceptible to infections and illness. It is common for spawning fish to sustain abrasions from jagged rocks and debris at the water’s edge. These cuts and scrapes are vulnerable to infection that can cause death. Typically, spawning stress fish kills occur slowly over the course of weeks. It is unclear how long the fish at Casey Lake were piling up near shore.

“Fish surveys conducted this week on Casey Lake showed that largemouth bass and bluegills are doing well, and black crappies are abundant,” Kirby added.

Iowa DNR encourages residents to call their 24-hour phone line at 515-725-8694 if they notice dead fish accumulating in lakes or rivers.

Iowa DNR suspects farm crop duster is responsible for Medapolis fishkill

(Florida Fish and Wildlife/Flickr)
Jenna Ladd | August 3, 2016

The Iowa Department of Natural Resources suspects that crop duster farm chemicals are responsible for killing thousands of fish in a southeast Iowa creek late last week.

A local resident near Mediapolis discovered the dead fish last Friday, July 29th and notified authorities. When investigators arrived they found a five-to-six mile stretch of the Cedar Fork Creek to be littered with slain freshwater species of all kinds including bass, catfish, crayfish, sunfish and chubs. Short sections of Flint Creek were also affected.

DNR quickly ruled out fertilizer or manure spill as potential causes. Ryan Stouder, environmental specialist with the organization says he’s confident that crop duster farm chemicals are the culprit,“The Department of Ag pesticide investigator is pretty confident it is, just off the visual signs of mineral oil in the water.” Investigators are unsure if the contamination was the result of unintentional drift or an emergency aerial dump. Water samples were collected from the scene in order to determine specific chemicals present. If a source can be identified, DNR will take appropriate enforcement measures.

The Iowa Department of Agriculture joined DNR in further investigation on August 2nd.

Manure spill affects nearly two miles of creek in northwest Iowa

A creek that runs through Story County, Iowa. (Carl Wycoff/Flickr)
A creek that runs through Story County, Iowa. (Carl Wycoff/Flickr)
Nick Fetty | July 7, 2016

Approximately 2,500 fish were killed after a manure spill in northwest Iowa last week.

The Iowa Department of Natural Resources reported that the spill occurred on June 30 when Doug Streit, an O’Brien County hog farmer, was transferring manure from one tank to another. A broken hose led to an estimated 5,000 gallons of manure spilling onto the ground but Streit quickly dammed the area above Barry Creek to prevent further spillage.

The spill contaminated nearly two miles of creek and mostly affected smaller fish like minnows, shiners, stonerollers and chubs. The site was cleaned up the following day using a pump and other equipment. Iowa DNR officials said they do not expect the spill to affect Waterman Creek downstream but will continue to monitor the situation and take appropriate enforcement action as necessary.

Manure spills can cause a slew of public health and environmental concerns. Not only can manure spills contaminate surface waters – such as creeks, rivers, and lakes – but manure can also seep its way into the ground and penetrate aquifers. Increased nitrate levels in waterways caused by manure spills can lead to blue-baby syndrome in infants. Elevated levels of nitrate and other compounds can also lead to fish kills and other ecological impacts.

According to the Iowa DNR’s Hazardous Material Release Database, nearly 350 spills have been reported since the start of the year. Iowa DNR encourages farmers, landowners, and anyone else from the public to report manure spills or suspected spills. Information on how to report spills and other resources are available on the Iowa DNR website.

Iowa DNR investigates fish kill in Johnson County

Oxford, Iowa. Photo by Ashton B Crew.

The Iowa Department of Natural Resources is investigating a fish kill in Rhine Creek near the town of Oxford, IA. The kill appears to have originated at a local agriculture chemical facility.

AgVantage of Oxford reported a leak of roughly 200 gallons of chemicals from its rinse tanks on Thursday morning. The chemicals pooled in the ground and then flowed into the nearby Rhine Creek.

AgVantage is working to clean the spill while the Iowa DNR continues its investigation.

For more information, read the full DNR news release.

Fish kill and orange water in Cheslea Creek

Photo by eutrophication&hypoxia, Flickr.

A fish kill is being investigated in Cheslea Creek near Mason City. The fish kill was discovered after the Iowa Department of Natural Resources received reports that the water in Cheslea Creek had turned orange.

This discoloration was traced to the Golden Grain Energy facility, which releases cooling water into the creek. It’s believed that excess sulfuric acid was added to the cooling water system, causing rust within the pipes to drain into the creek.

The Iowa DNR is still determining penalties for Golden Grain.

Read more here.

Des Moines River fish kill attributed to high temperatures

Photo by eutrophication&hypoxia, Flickr.

The Iowa Department of Natural Resources says high water temperature is to blame for a recent fish kill in southeast Iowa.

Nearly 58,000 dead fish were counted in a 42-mile section of the Des Moines River, with an estimated value of more than $10.1 million.

Mark Flammang, a DNR fisheries biologist that investigated the kill, attributed the event to water temperature.

“You just don’t see rivers at 97 degrees, and it was 97 degrees at every site that we sampled,” Flammang said. “I’ve never seen water at that temperature in Iowa.”

For more information, read the full article at The Gazette.

Thousands of carp die during marsh restoration

Photo by mclii, Flickr.

In an effort to restore the Ventura Marsh in Ventura, Iowa, thousands of carp have died and washed up on land.

For the $5 million restoration a new emergency spillway and a new pump station were constructed. The pump was used to lower the marsh’s water level, causing the fish kill.

Eliminating some of the carp population was part of the goal during the restoration. Rough fish, like carp, stir up sediment and prevent the marsh from acting like a filter for water going into the lake.

Read more about the restoration project here.

Read an article about a decision to let the dead carp decompose naturally here.

DNR unable to link fish kill to pollutant

Photo by Striatic, Flickr

A recent press release from the DNR indicates that the cause of a Hamilton County fish kill could have been determined if the citizen who noticed the dead fish hadn’t waited a day before reporting it.

This fish kill was the smaller of the two reported by the Iowa Environmental Focus earlier this month. According to DNR estimates more than 33,000 fish were killed between the two incidents.

While it’s believed the fish kill resulted from a aerial-sprayed corn fungicide, their were no traces of this pollutant or any other by the time the stream was tested.

The DNR encourages immediate reporting of dead fish to their 24-hour spill line: 515-281-8694.

Dubuque Fish Kill linked to Dairy Farm Runoff

A menhaden fish kill in August 2003 due severe hypoxia--near anoxia--in Greenwich Bay in Narragansett Bay, Rhode Island. credit: Chris Deacutis

Farm runoff can be deadly. Seriously.

A DNR investigation in early December found that runoff from a dairy west of Bernard in Dubuque County killed over 2,000 fish in an unnamed stream in late November, the Dubuque Telegraph-Herald reports.

Casualties included minnows, shiners, chubs, suckers, dace and sunfish.

The investigation identified many factors that led surface-applied manure to run off the 40-acre field, including: heavy rains, minimal corn stock residue, field slope, inadequate separation distances, limited manure incorporation, and not checking the area for recent drainage improvements.

“This incident highlights the need for manure-application planning and for choosing low-risk areas for application,” Rick Martens, a DNR environmental specialist at the Manchester field office told the paper.