provided by Clinic for the Rehabilitation of Wildlife
Red tide is the result of a specific kind of harmful algal bloom. Algal blooms result from a combination of environmental factors including available nutrients, sunlight, temperature, ecosystem disturbance, hydrology, and water chemistry. Harmful algae blooms can also be the result of nutrient dense waste, such as nitrogen or phosphorus rich water which can enter aquatic systems by way of fertilizer runoff or other pollution such as herbicides and pesticides. Some of these algal blooms can get so large they are visible from outer space satellite images.
Many of the seabirds, shorebirds, and wading birds at CROW are admitted due to complications from red tide, although a large population of the public do not know exactly what red tide is, how it forms, or how it affects wildlife, humans, and the environment.
Red tide is a higher-than-normal concentration of microscopic algae. This algae formally called Karenia brevis or K. brevis contains powerful neurotoxins known to kill fish and make birds, and even humans sick. These toxins can exist for over six months in aquatic vegetation which is consumed by marine animals like sea turtles and manatees. Bird species who rely on fish as their food source can experience secondhand poisoning. This affliction is known as brevetoxicosis and can affect these animals in numerous ways; this includes an inability to fly, lethargy, balance issues, and inability to perform their natural behaviors such as preening, hunting, and they may even lose their fear of humans. Seabirds can appear ‘drunk’ on the beach unable to walk or fly straight. Usually, these birds do not evade capture due to their illness. When left untreated, red tide poisoning results in mortality.
At CROW, a large majority of seabird intakes are due to red tide, especially seabirds like Double-crested Cormorants, Brown and White Pelicans, Laughing Gulls, and terns. Although these algal blooms occur naturally, human impacts such as pollution and runoff can cause the growth of the algae to become more frequent and severe. Runoff from Lake Okeechobee and other large bodies of polluted water can affect areas of southwest Florida such as Sanibel and Captiva Islands. This water can discharge pollutants downstream and eventually filter into the ocean upsetting the salinity balance.
An effective method of treatment has been implemented to help combat red tide poisoning. Intravenous lipid emulsion therapy, or IVLE involves pumping lipids into the bird’s bodies via catheters. These lipids then bind to the neurotoxins (called brevetoxins) to be excreted from the body. When found within 24 hours of noticeable symptoms, patients have a success rate of over 80% when treated with IVLE. Intravenous lipid emulsion therapy treatments have helped to reduce the time animals will spend in rehabilitation, save resources, and increase survival rates thanks to the more rapid resolution of clinical signs in affected animals.
Doing your part to combat red tide can include being mindful about where your waste goes. Consider using natural fertilizer with less chemicals when tending to your garden. Additionally, avoiding use of materials that contain an excessive amount of phosphorous or nitrogen can help prevent dangerous runoff into waterways. Always be mindful of trash and do your part to help litter control in your area. If you do see an injured or symptomatic animal that might be suffering from red tide poisoning, call your local animal rehabilitation facility or CROW for further guidance.
THIS WEEK AT CROW (1/7-1/14):
There were 31 new patients admitted to CROW’s Wildlife Hospital including seven eastern cottontails, five double-crested cormorants, three white pelicans, three brown pelicans, a red-bellied woodpecker, a southern flying squirrel, a spotted skunk, and a cattle egret. Recent Releases include a turkey vulture, a Cooper’s hawk, a southern flying squirrel, a blue jay, and a big brown bat. Check out a full list of CROW’s current patients and recent releases.
Wildlife doesn’t have health insurance! Your donations help cover the costs of medical and rehabilitative care for over 5,000 patients admitted to CROW’s Wildlife Hospital each year.
Want to learn more about wildlife rehabilitation? Stop by CROW’s Visitor Education Center at 3883 Sanibel Captiva Road.
About Clinic for the Rehabilitation of Wildlife (CROW)
Established in 1968, the Clinic for the Rehabilitation of Wildlife (CROW) is a teaching hospital saving the sick, injured and orphaned native and migratory wildlife of Southwest Florida and beyond. Through state-of-the-art veterinary care, public education programs and an engaging visitor center, CROW works to improve the health of the environment, humans and our animals through wildlife medicine. For more information, or to plan your visit, go to www.crowclinic.org. If you find an animal that is in need of help, call (239) 472-3644 ext. #222.