February 15-18, 2009 Washington State Convention Center Seattle ...

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EXPLORING THE UTILITY OF A GIS IN EVALUATING THE RISKS AND IMPACTS OF
CATFISH TREMATODE TO ARKANSAS AQUACULTURE
Alf Haukenes*, Larry Dorman and Andrew Goodwin
Aquaculture/Fisheries Center of Excellence
University of Arkansas at Pine Bluff
Pine Bluff, AR 71601 USA
ahaukenes@uaex.edu
Standardized surveys targeting the incidence of specific fish diseases can provide a wealth of information that can be integrated
into a GIS to examine spatial relationships characterizing disease risk. A GIS provides a working format for both the analysis
and the display of complex epidemiological interactions in time and space. Such an approach is useful when identifying the
influence of risk factors or describing potential impacts of fish pathogens as well as distributing ‘real-time’ information to local
extension personnel. We are exploring the use of a GIS to characterize the distribution of catfish trematode in commercial
aquaculture ponds. A two-year sampling effort (2006-2007) was conducted in the state of Arkansas to collect data describing
the prevalence and intensity of catfish trematode infections in commercial ponds. The survey included observations on the
presence of catfish infected with the parasite and on other potential risk factors including the presence of the bird and snail hosts
for the parasite. A simple exploration of the data illustrates the geographic distribution of certain risk factors for the establishment
of the disease (Fig. 1). Catfish farming is a widely distributed in Arkansas and the intermediate snail host for the catfish
trematode was found in ponds from 10 of the 12 sampled counties. Four counties contain ponds where the multiple risk factors
of the snail host and moderate to heavy bird populations were present. In 2006, Ashley and Chicot counties were the only two
counties that contained ponds affected by catfish trematode, however these two counties are the dominant producers of channel
catfish in the state. We are combining the results of the 2007 catfish trematode survey to our GIS and will begin to focus on
different geographic scales to evaluate the distribution of catfish trematode in order to determine factors that help define the
expansion or contraction of the range of distribution of catfish trematode in the state of Arkansas.