logɪo transformed. Three outlying data points were excluded from analysis: one crazy ant
control colony for sugar water consumption, one crazy ant control colony for mortality,
and 1 competing pair of colonies for total ants in the other species nest box. When
transformations to normality were not possible, Wilcoxon signed rank tests were
performed for each factor (instead of an ANOVA) or mean difference (instead of a 2-
tailed t-test). The specific test used for each response variable is shown in Table 3.1.
Bait dominance was analyzed for a species effect using binomial probability.
Crazy ant addition field experiment
Field research was conducted at the University of Houston Coastal Center
(UHCC) in La Marque, TX (29.38oN, 95.04oW). The 400-hectare property has
approximately 80 hectares of undisturbed native prairie, with the remainder of the
property composed primarily of non-native woody species (especially Chinese tallow tree
[Triadica sebifera]). In April 2007, Rasberry crazy ants were found in high abundances
in the southwest comer of the UHCC property. It is unknown how the ants were
introduced to UHCC; they may have arrived with a load of contaminated fill dirt, or they
may have spread from a possible infestation at the landfill on the western border of the
UHCC property. In the infested area, nests were located in the woods, but foraging ants
were readily apparent in open spaces, including roadways and prairie. The population
appeared to be unicolonial, with no noticeable aggression between nests (Holldobler and
Wilson 1990).
Because the high-density infestation was limited to the southwest comer of the
property, we were able to locate an area without a high abundance of crazy ants in the
southeast comer of UHCC in a prairie bordered by woods, approximately 750m from the
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