Last Friday, the Nebraska Game and Parks Commission, in conjunction with the Nebraska Department of Environmental Quality and Health and Human Services issued health alerts for harmful algal blooms in four Nebraska lakes. Known as toxic blue-green algae blooms, these health alerts have been issued for Kirkman’s Cove in Richardson County, Rockford Lake in Gage County, Wagon Train Lake in Lancaster County and Willow Creek Reservoir in Pierce County.
While none of these lakes are in our immediate vicinity, it has happened here. It was only a few years ago that we had alerts like this for Red Willow Reservoir. We have had testing done on Sutherland Reservoir and Lake Maloney when the right conditions appeared to produce algae blooms. Issuing alerts like this is a cautious and prudent move on the part of state officials.
I have not seen any of these alerts in western Nebraska. I think the primary reason has been the rains we have received. The rain and inflows into area waters has kept the overall water temperatures down. Warm water temperatures are one of the essential elements of an algae bloom.
Where do toxic blue-green algae blooms come from? Why do these algae blooms occur? As a biologist, the cause and effect of these blooms interests me.
There are many types of naturally occurring blue-green algae in Nebraska waters. It’s nothing new. In fact, fossil evidence suggests that blue-green algae have been around for millions of years. There are writings of blue-green algae blooms dating back 600 years. There are even more scientific studies documenting the toxic effects on livestock for more than 100 years.
The specific type of algae that cause the problems is known as a Cyanobacterium. The blooms often occur when the water is warm and enriched with nutrients like phosphorus or nitrogen. Fertilizer runoff is a common cause of these nutrients getting into lakes and ponds. Even residual laundry detergents can be a cause of these blooms.
When the right environmental conditions come together, blue-green algae can grow very quickly. It will form clumps that float to the surface and create a scum layer. The result of a blue-green algae bloom can range from discolored water, reduced light penetration, taste and odor problems, dissolved oxygen problems causing fish die-offs, and toxin production. It is the toxin production that prompts the health alerts.
Blue-green algae can cause health problems for humans and animals. This algae is capable of producing several different toxins. People may be exposed to these toxins via contact with the skin while swimming, through inhalation (breathing in water droplets while skiing), or by inadvertently swallowing contaminated water.
The Nebraska Department of Environmental Quality goes out weekly from May through September to take samples in 52 recreational lakes across the state, focusing on swimming beaches. When the levels reach 20 parts-per-billion the NDEQ issues public health alerts.
Types of toxins and potential health effects vary widely. Some of the more common toxins produced by blue-green algae that can cause allergic-type reactions such as rashes, eye/nose/throat irritation, and asthma, headaches, fever, nausea, stomach cramps, vomiting and diarrhea.
Other toxins can impact internal organs, and can cause gastroenteritis, tissue damage, muscle weakness, and paralysis in severe exposure cases. One of the more interesting effects (from a biologist’s perspective) can be chromosome loss and DNA strand breakage. Still other toxins can attack the central nervous system and can cause seizures, paralysis and respiratory failure or cardiac arrest. It can be quite serious.
Pets and livestock can become extremely ill. There are documented cases of animals dying from drinking water containing blue-green algae. Nebraska saw cases of pets becoming extremely ill and dying several years ago from blue-green algae ingestion a couple of years ago.
Another potential problem is fish kills. When a blue-green algae bloom runs its course and begins to dies off, algae cells begin to break down. This process requires oxygen and can create a greater biological oxygen demand in a body of water. If enough oxygen is used in this process, dissolved oxygen in the water can be reduced and that can threaten the fish population.
Cooler fall temperatures are on the way and I think it would be very unlikely to see types of blooms in our part of the state until next summer. However, if one were to be issued for you favorite lake, follow the recommendations provided by the state’s heath organizations. Blooms will run their normal/natural course and be gone as quickly as they appear. Having this knowledge is the best way to protect yourself, your family, and your animals.
Are toxic blue-green algae a real threat? Yes. Can it be avoided? Yes. Just pay attention and be safe out there.
Brule Gun Show
Make sure to mark your calendars for the Brule Gun Show, Sept. 7 and 8. Doors will be open 9 a.m. to 5 p.m. MT on Saturday and 9 a.m. to 4 p.m. on Sunday at the Brule Activities Center, 8th and Oak streets. Admission is $5 for adult or $9 for both days. Refreshments and lunch are available on site, so you can make a day of it. There will be a raffle and drawing for the winner’s choice of either a S&W M&P 380 Shield EZ or Weatherby Vanguard SS .223. For more information, call Stef at 308-233-2501.