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Thursday, Apr 26, 2018
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Saint Leo team monitoring mangrove health

ST. PETERSBURG - They are the stinky trees. Mosquito factories. Barriers to our cherished water views. But Florida’s mangroves are also valuable wetland habitats, coastal water filters, defenders against storm surge, and they help mute the effects of climate change. A group from Saint Leo University in Pasco County is compiling a record of Tampa Bay’s mangroves, the tropical trees that thrive in saltwater at the edge of shore. Crews of faculty and students led by biology professor William Ellis have been recording the condition of the Tampa Bay shoreline with video and still cameras, global positioning devices and spoken and written anecdotal observations. “We don’t really have any record of their condition at this scale, and this will provide that,” Ellis said. The idea is to obtain a baseline documenting the existing condition of the mangroves in order to note changes from year to year.
“We look at the condition of the trees themselves,” Ellis said. “Is the canopy whole? Is there evidence of dead trees? Bare branches? What about seedling density? What about the oyster coverage?” On a recent afternoon, a crew puttered through St. Petersburg’s Coffee Pot Bayou, where the seawalls of high-end waterfront homes still support a few patches of mangroves. From their 21-foot Carolina Skiff, the Saint Leo group records the entire waterfront, concrete or green. “We’ve seen areas that have been potentially damaged by herbicides,” Ellis said. “They drain through the mangrove sites, and we’ve seen some die off.” In other spots, though, the group has documented expansion of mangroves. “It’s certainly not a totally dire situation.” Ellis took on the project after seeing a presentation about a similar effort in Australia undertaken by renowned researchers Norman Duke and Jock MacKenzie of James Cook University. Their group, MangroveWatch, originated as a comprehensive resource on the ecology and identification of mangroves, as well as a source for monitoring and research initiatives. MangroveWatch says the vital coastal plants are disappearing worldwide at the rate of 2 percent a year. Locally, the Tampa Bay Estuary Program estimates that nearly half the mangrove swamps that once ringed Tampa Bay have been replaced by development and seawalls. But since the dredges and bulldozers ran wild in the post-World War II era, “I’d like to think we’ve reached the end of that in this area,” Ellis said. “I hope that we know better now.” Indeed, there are now strict rules on trimming and altering mangroves in state law. In 2011, the town of Jupiter fined a couple $1.6 million for ripping out 109 mangroves on their Loxahatchee River property; the fine is being appealed. Dana DeLosa, a junior in biology and environmental science at Saint Leo, has come around on the oft-maligned plant. “Before I got involved, it was just, ‘Oh, the stinky trees.’ But doing this project has really helped me understand the importance of them,” DeLosa said. “I came out a couple of times last semester and I really liked it, so I’ve been coming out ever since.” Chris Lambert, a junior biology major, is conducting seabird research in conjunction with the mangrove project. “I love all branches of science,” the Rhode Island native said. “And I love the wildlife here.” Ultimately, MangroveWatch envisions a “Shore View” concept similar to Google’s “Street View,” where the curious public can click along and view what observers have recorded. The researchers also hope to share their information with communities. While the Saint Leo team sticks to Tampa Bay, Ellis is hoping to recruit additional “citizen scientists” to conduct similar observations in Charlotte Harbor, Marco Island, the Pinellas Gulf coast, and other areas around the state. “The more people we get involved with this, the more people won’t see the mangrove as a mosquito factory,” Ellis said. “They’ll view it as part of the beauty of Florida, and they’ll try to maintain it.”

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