Aquatic Invasive Species

Every year, invasive animals, plants, and every type of living organism find ways to infiltrate across borders to infect exotic ecosystems. These invaders have caused devastating losses in biodiversity, radical changes in environment, and fluctuations in ecosystem makeup. In nearly every case these effects have been traced to problems in agriculture, the economy, and human interaction around the world. Scientific studies have discovered these invasive species’ transportation by the hulls of tanker ships, by farmers looking to increase their output, and even by the waders of unknowing fishermen. Many efforts have already been enacted to slow the flow of invasive species. However, it may be surprising to learn that local nurseries could very well harbor invasive aliens. Due too a lack of government restrictions on the trade of horticultural plants, many invasive species such as the Brazilian pepper, melaleuca, Java plum, and Gold Coast jasmine have all been bought and sold in nurseries across the state of Florida. These invaders threaten Florida’s many unique ecosystems. Places such as the Everglades or the Keys harbor life unlike anywhere in the world and invasive species are one of their major threats.

This is by no means the final word on the matter. Efforts around the world are taking place to stem the flow of invasive species through horticultural trade. Nikki Rigl, a researcher from Duke University in Durham, North Carolina hopes to address this problem in a study. “When people think about invasive species, they do not think about their plants,” said Rigl in an interview. She plans to decrease the knowledge gap between Florida citizens while determining the threat posed by the horticultural trade as a vector for invasive species. She proposes a state-wide survey of random nursery owners and other horticultural traders about invasive plants and their views on selling this volatile species.

The survey will ask a variety of questions ranging from typical “age?” “sex?” “location?” questions to more specific questions on horticultural trade in Florida. Each respondent will be asked to identify certain invasive species from a photograph, their opinion on the “invasive” status of a plant, and about the likelihood for them stocking invasive plants. Rigl hopes that the information obtained from these questions will help shed some light on the issue of invasive horticultural plants in Florida.

A similar study conducted in Minnesota was published in 2006. The researchers, Peters, Meyer, and Anderson, found that horticultural professionals in the state for the most part supported efforts to curb invasive species expansion. However, the study also found that many of these experts were unable to identify certain invasive species and that more than half of them reported that they would sell known invaders if faced with economic competition. It is this lack of information about invasive species that Rigl sees as the main problem. “The main problem is the knowledge gap…. If people knew the detrimental effects of certain species they would be less likely to deal with them.”

Whatever the results of the study indicate, Rigl believes the survey will ultimately create a better understanding about invasive species in the horticultural industry. Nurseries and other aspects of the horticultural industry are often a direct link between people and nature, and she feels that educating the professionals here will spread to the rest of the community. Rigl believes that this survey will provide a cheap way to stimulate education efforts throughout the state of Florida, and through this provide the foundation for future efforts to slow and perhaps even stop the flow of invasive horticultural plants once and for all.

The Brazilian peppertree, an invasive species from southern South America, intruded on Florida before the 1900s and spread to Texas and Hawaii soon after. Specifically in Florida, this weed plagues pine land, hammock, and mangrove dwellings as well as the Everglades National Park. In the 1980s, a search for Brazilian pepper’s natural enemies for use as biological controls began and several candidate agents were unearthed. The TAG advocated the release of P. ichini in May 2007. First examined in Brazil, these thrips proved effective in reducing the strength and reproductive rate of Brazilian pepper in both their larval and adult stages. Using snap cap vial quarantine experiments, researchers developed a mass-breeding technique to verify that ample healthy insects could be released as control agents. These trials proved successful and allowed the Entymology and Nematology Department to gain approval for conducting field releases of P. ichini against the Brazilian pepper in locations throughout Florida.

Cuda, J. P., Gillmore, J. L., Medal, J. C., & Macedo, J. H. P. (2008). Mass rearing of pseudophilothrips ichini (thysanoptera: Phlaeothripidae), an approved biological control agent for brazilian peppertree, schinus terebinthifolius (sapindales: Anacardiaceae). The Florida Entomologist, 91(2), 338. Retrieved from http://search.proquest.com/docview/219330109?accountid=10598