Synthetic fertilizer use contributes to manatee, dolphin, and pelican deaths

Photo Credit: Jim Reid, USFWS Photo Credit: Jim Reid, USFWS

Synthetic fertilizer running off into the Indian River estuary may have contributed to disrupting the balance of its rich marine ecosystem. Recent nitrogen spikes in the water have caused large algal blooms, which blanket the estuary and kill the underwater sea grass fields that are the main food source and habitat for the estuary fauna. Sea grass is a large part of the manatee diet, and its disappearance has coincided with Banana River manatee deaths, potentially caused by algae consumption. In the past year, 280 manatees have died, accompanied by pelicans and bottlenose dolphins. While the specific causes of these deaths remain elusive, many scientists hypothesize that the algal blooms are responsible. The estuary is badly overloaded with nitrogen, an essential plant nutrient found in fertilizers, containing 45 percent more nitrogen than is acceptable. Researchers fear this may signal the collapse of the delicate estuary ecosystem.