In March 2024, boaters at McGee Creek Reservoir, located in Atoka County, Oklahoma, noticed unusual jelly-like masses hanging from submerged tree limbs beneath the water’s surface. At first glance, these strange formations looked eerie and almost alien, resembling something out of a science fiction movie. However, upon closer examination and investigation, it was revealed that these mysterious blobs were actually a natural and common part of a healthy aquatic ecosystem.

The Oklahoma Department of Wildlife Conservation (ODWC) provided clarification about what these gelatinous masses really are. They explained that these formations are colonies of bryozoans, also known as moss animals. Bryozoans are tiny aquatic animals that live together in colonies made up of numerous small individuals called zooids. Each zooid is a small, filter-feeding organism, and together they form large, visible clusters. The gelatinous and somewhat translucent appearance of these colonies comes from their protective outer covering, which is made of chitin.

Underwater, this shell feels soft and somewhat squishy to the touch, but when exposed to air and dried, it hardens and becomes brittle. Bryozoans are capable of rapid reproduction and growth, especially when water conditions are ideal, allowing these colonies to expand quickly and cover submerged surfaces like tree branches, rocks, or aquatic plants. Although their unusual shapes and textures might make them appear alien or unsettling to some, bryozoans are entirely harmless to humans and other wildlife. In fact, they play an important ecological role in freshwater environments.

One of the key benefits bryozoans provide is their ability to filter water. They feed by filtering out bacteria, tiny particles, and organic matter from the water, which helps improve water clarity and overall quality. This natural filtration process contributes to maintaining a clean and balanced ecosystem. Moreover, bryozoans serve as a vital food source for various aquatic animals, including fish, snails, and mussels, supporting the local food web.

Interestingly, bryozoans are indicators of healthy and clean water because they tend to thrive only in environments with good water quality. Therefore, the presence of bryozoan colonies in McGee Creek Reservoir is a positive sign that the lake’s ecosystem is functioning well and maintaining a healthy balance.

From a historical perspective, bryozoans are fascinating creatures due to their longevity on Earth. Fossil evidence shows that bryozoans have existed for approximately 470 million years, making them some of the oldest living multicellular organisms still present in today’s aquatic habitats. Their long evolutionary history speaks to their adaptability and resilience in a wide range of environmental conditions.

So, the next time you see these strange, jelly-like formations hanging from underwater trees or rocks, remember that they are not strange alien invaders, but rather a remarkable and beneficial part of nature’s aquatic world. Bryozoans contribute to the health of freshwater ecosystems and have been quietly thriving beneath the water’s surface for millions of years.