A double crested cormorant spreads its wings. Credit: US Fish and Wildlife Service

The NCCOS Harmful Algal Bloom Event Response Program awarded $8,250 to Florida’s Clinic for the Rehabilitation of Wildlife (CROW) and the Florida Fish and Wildlife Conservation Commission Fish and Wildlife Research Institute (FWRI) to study a novel treatment for cormorants sickened by exposure to brevetoxin resulting from red tide. The results could provide insight for treating other marine animals in the future.

A bloom of the red tide organism Karenia brevis, which produces brevetoxin, has persisted and expanded off the coast of Southwest Florida since October 2017. The bloom has led to the deaths of fish, sea birds, marine mammals, and turtles, which are exposed to the toxin either via their diet or breathing in airborne toxins. In humans, the health impacts of brevetoxin can range from itchy, watery eyes, to a severe cough, to gastrointestinal or neurotoxic effects.

Wildlife rehabilitation centers have been overwhelmed with sick animals and struggle to provide effective treatments. Additionally, the red tide has severely impacted the region's economy, as the bloom is deterring tourists and leading to closures of shellfish beds and beaches to protect public health.

CROW’s study is investigating the effects of a high-lipid emulsion therapy on cormorants that are sickened with brevetoxicosis. This method has previously proven effective in treating other, similar types of neurotoxin illnesses in different animal species. In cormorants, survival rates have increased 22 percent in treated birds.

This event response funding supports testing for the presence and levels of brevetoxin in the cormorants' plasma following treatment, in order to demonstrate the efficacy of the therapy. Should the findings support the survival data, the method can be expanded to treating other marine life. This is particularly timely going into the fall, when K. brevis typically thrives near shore.

The NCCOS HAB Event Response Program provides immediate assistance to help federal, state, and local officials manage events and advance the understanding of HABs as they occur.

For more information, contact Quay.Dortch@noaa.gov.