Title: Brazillian pepper biological control in Florida
[By Patricia Behnke] Florida's sometimes fragile ecosystems are poised on a balance beam as a growing population and changing climate challenge wildlife managers. Florida's environment complicates the issues, because it is a welcoming host to invasive plant species. It also covers two climate zones - subtropical and temperate, allowing some invasive species to invade other regions with impunity.
According to a 2006 report from the U.S. Geological Survey on invasive species and climate change, "If climates change, then new invasive species may disperse into novel climate regions." The report urges managers on the edge of an invasive species' range to be aggressive in treating the spread of those nonnative species that take over a region and hold ecosystems hostage in a battle with native species for supremacy.
"Highly disturbed landscapes are more prone to invasion by nonnative plant species," said Don Schmitz with the Florida Fish and Wildlife Conservation Commission's (FWC) Invasive Plant Management Section. "Just look at the Everglades - a highly disturbed ecosystem. Disturbance has left it more prone to invasives, such as the Brazilian pepper plant."
The growth of the nonnative Brazilian pepper has damaged mangroves, and as predicted sea-level changes occur, the mangroves will feel some of the first effects. The invasion of Brazilian pepper creates a battlefield in the mangrove communities. And quite a community it is - mangroves support all manner of flora and fauna in the Everglades and other brackish estuaries along the coast. Without mangroves, a variety of wildlife also would vanish, including invertebrates, fish, birds, amphibians, reptiles and mammals. Florida softshell turtles and alligators; bobcats and manatees; cattle egrets and brown pelicans; snook and cobia - all of these species and many more call the mangroves home and depend upon their foliage, roots and shelter for sustenance.
The FWC recently published a report on its climate change summit held last year. One of the summit's workshops dealt with the effects of invasive organisms on biodiversity during climate change. Greg Holder, the FWC's Southwest Region regional director, led the workshop.
"If we are to do a good job of restricting the movement of invasive species when the opportunities arise, we will need to be vigilant and more fully understand the potential impacts on native habitats and species," Holder stated.
That's a tall order for a state with a warm and moist climate, which will only be enhanced by the changes in climate, but wildlife managers in Florida are following the suggested practices of the U.S. Geological Survey by aggressively controlling some of the more-invasive invasives. The Old World climbing fern is an invasive that can cover and smother native species and act as a fire ladder into native tree canopies that normally wouldn't burn during Florida's common ground fires. The FWC's Invasive Plant Management Section funded nearly $1 million in development and introduction of a moth that preliminary field research indicates will destroy the ability of this fern to form dense canopies that destroy native tree communities. The research has been led by the U.S. Department of Agriculture, with funding support from the FWC and the South Florida Water Management District.
The USDA spent five years host-testing in Australia and Florida before introducing the moth at Jonathan Dickinson State Park, in Martin County, in January 2008. The USDA reported in January 2009, "During the year since the moth's release and subsequent release at two other sites in the park, it has developed very large numbers and has begun to subdue the weed through the activities of its leaf-feeding caterpillars." It is true that environmental and wildlife managers must do their part on a large scale, but as individuals, we can do our part to lessen their load.
"Folks can begin by not planting nonnative plants and replace invasive and nonnatives already in the yard with native species," Schmitz said. "We have to start somewhere, and this is one instance where it really can begin in our own backyard." The National Invasive Species Council 2008 management plan states that, "Reducing the negative impacts of invasive species should better enable natural ecosystems to withstand the threats of climate change." If that's the case, we are standing steady on the balance beam in Florida - protecting one plant, one species, one ecosystem at a time.