Red Tide: Karenia Brevis

We all remember our first time-at least I do. My heart pounded. I was short of breath. My throat hurt. I even had a few tears tugging at the corners of my eyes. The air was heavy and had a pungent smell that seemed to hang over the moment. Waves from some long forgotten hurricane pounded the shoreline an as I looked to the horizon ready to plunge in to the warm salty water of my first true love, I noticed a frothy red sheen veering the surface of the ocean. My first sight of red tide, where did you think I was taking this, this is a family publication, was one I was not soon to forget.

As we enter the warmer periods of the Gulf season, we as stewards of the coast must be on a careful look out for the first warning signs of any harmful algae blooms (HAB's). Karenia brevis, the Red Tide,is the most common bloom we will experience in the Western Gulf of Mexico and here are a few tips to help you recognize the bloom, health tips to protect yourself and loved ones, what you can do to take an active role to protect your local ecosystem, and report Red Tide Blooms in you area.

What is Red Tide

Scientists do not share a consensus on the exact causes of red tide; however, they believe Karenia brevis is always present in the world's oceans. The actual blooms produces a biological toxin that affects the central nervous systems of birds, fish, and other animals. Blooms typically last from days to months. Moreover, the effects of red tide can change daily from affects of winds and tidal currents.

The first signs of a red tide outbreak often manifests itself in large fish kills of filter feeding fish. Case in point, the Red Tide outbreak of 2005 that closed parts of South Padre Island and killed thousands of fish in the lower Laguna Madre and around Port Mansfield first exposed itself with thousands of dead mullet and menhaden.

Jeff Paternoster of NOAA's Southeastern Phytoplankton Monitoring Network (www.chbr.noaa.gov/pmn/) and Meredith Byrd of Texas Parks and Wildlife's Harmful Algae Network (www.tpwd.state.tx.us/landwater/water/environconcerns/hab/) devote their careers to the Red Tide. "Red Tide blooms in Texas occur roughly every three to five years," Paternoster says, "However, we are witnessing an increase in blooms over the last thirty years." Paternoster and Byrd are not sure of the direct occurrences of the higher bloom frequencies. "Warmer oceans may be a contributing factor; however, we also may simply be witnessing an increase in awareness and education." Paternoster said.

The good news for Texans this year is with two hurricanes, Dolly and Eduardo, making an unwelcome visit we may be safe from a red tide bloom. Typical Red Tide blooms require a salty sea with salinities greater than 24 parts salt to 1000 parts water. In a recent trout stocking foray with TPW Hatcheries biologists, the lower Laguna Madre was a sweet 15 parts salt. The low salinities were well below the advertised hyper-salinity that makes the Mother Lagoon so famous. With such low salinity levels, Karenia brevis cannot survive to raise her venomous head.

Health Tips

Commercially purchased seafood is safe from red tide infected fish. The FDA and government organizations highly regulate commercial fishermen from fishing Red Tide infected waters. However, if you are reading this, most likely, you are recreational angler. Here are a few things to think about if we are unfortunate enough to experience a bloom.

The most important thing to remember is not to eat crustaceans during a red tide boom-especially oysters. The bivalved oyster is a prolific filterer of the ocean and the toxins will manifest themselves in the meat of the shellfish and can be detrimental to human health. The ban on shellfish foods also extend to whelks and clams. The result of eating an infected shellfish will result in Neurotoxic Shellfish Poisoning and can lead to hospitalization. However, common to most belief, shrimp and crab are not unsafe to eat during a red tide bloom. As long as the food does not appear to be sick or dying, human consumption should be safe.

Although illegal in Texas, unfortunately some folks ignore the law and try to cull dying or dead fish from local bays. Fish killed from a red tide bloom are unhealthy and not safe for human consumption. I know it may be easy to rationalize to any sane angler that a twitching 30-inch trout, and yes I have seen them that size killed in a HAB, is "going to die anyway, why not give it a purpose in death?" Unless you want a quick trip to the ER, stay away, do not handle, if possible collect in a plastic bag to give to TPW officials, and take a picture. While photographing, try to take a panoramic to capture the breadth of the resulting fish kill.

Reporting Red Tide

We, as anglers on the water everyday, are the first line of defense in the war against red tide. To learn more about the red tide or to report fish kills or suspected red tide blooms call Texas Parks and Wildlife at 512-389-4848. To report nationally, contact Jeff Paternoster at 843-762-8657. Paternoster can also come speak to your club if you want to create a monitoring network in your home waters to detect and protect your local fishery.