Predators and Invaders in Florida Container Communities

Predators and Invaders in Florida Container Communities

P. Lounibos, M. Griswold & B. Alto, U. of FloridaB. Kesavaraju & S. Juliano, Illinois State U.

1. Invasive A. albopictus are preferred to native O. triseriatus as prey of larval predators in Florida containers (Fig. A).

2. The coexistence of these two prey mosquito species is promoted by high levels of predation and leaves (Fig. B).

3. In container communities, C. appendiculata controls prey diversity and T. rutilus regulates abundance (Fig. C).

4. The demonstration of effects in experimental tires suggests an important role of predation in limiting invasion success (Fig. D).

Corethrella appendiculataIV instar consuming Aedes II

Aedes albopictus(invasive)

Ochlerotatustriseriatus (native)

Toxorhynchites rutilus IV instar consuming Aedes IV

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Proportion A. albopictus available

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SD)

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Fig. A. Both C. appendiculata and T. rutilus (not shown) significantly (α>>.52) preferred A. albopictus at all ratios.

Fig. B. Composite index of performance shows high levels ofFood (leaves) and predation favor coexistence of two prey spp.

Control 2 C. append. 1 T. rut. Both

Fig. C. A low level of C. appendiculata predation supports prey co-existence compared to controls with no predators, and survival with T. rutilus alone is not different from both predators together

Fig. D. A significant treatment effect on A. albopictus abundance was mainly attributable to tires w/o predators vs. tires with predators

Experiments conducted in beakers with both prey species (24h: Fig. A) or separated (hatch to adult

Fig. B), varying food and predation levels.

Experiment outdoors in screened beakers to examine role of predator species

Month-long experiment to examineinvader recruitment w & w/o predators