By Bryan Swistock
Pennsylvania contains thousands of natural and man-made ponds and lakes. Past surveys have found that nuisance algae growth is one of the most common complaints from pond and lake owners, especially during late summer months.
Pennsylvania contains thousands of natural and man-made ponds and lakes. Past surveys have found that nuisance algae growth is one of the most common complaints from pond and lake owners, especially during late summer months. In recent years, harmful algae blooms or HAB’s have become more concerning to pond and lake owners. HAB’s are caused by certain types of blue-green algae that can produce toxins which cause injury or death to animals or humans who interact with the water. These algae are a type of photosynthetic bacteria called cyanobacteria. Under certain conditions in mid to late summer, cyanobacteria grow quickly or “bloom” to create floating scums which sometimes result in the release of dangerous toxins. These toxins can cause noxious odors, kill animals or wildlife, produce skin irritation, and cause various gastrointestinal illnesses which then limit the use of pond water for fishing, swimming, irrigation or animal watering.
Penn State Extension conducted research in 2015 and 2016 on harmful algae blooms in Pennsylvania and found 20% of pond and lake water samples submitted during the project contained at least one HAB species. The most common species of harmful algae observed were Aphanizomenon, Microcystis and Anabaena. It is important to realize that, while HAB species of algae are commonly found in ponds and lakes, only under ideal conditions will they bloom and release toxins.