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The Deepwater Horizon oil spill affected over one thousand kilometers of the southeastern United States coast in the Gulf of Mexico especially Louisianas salt marshes. These marshes are a vital part of the states economy and coastal ecology; however, the insects residing in this area remain largely unstudied. The goal of my project was to answer specific questions arising from two ongoing investigations of the insects in the oiled marshes. I sampled insects using sweep nets and insect vacuums to determine the most efficient technique to use in the marsh, compared insects collected in oiled and non-oiled marshes, and completed a taxonomic list of all of the insects collected in the marsh. I determined the effect of weathered oil on the mortality and foraging behavior of the ant Crematogaster pilosa. I used the house cricket, Acheta domesticus, to test the effect of direct and indirect oil exposure on insect mortality. I also used colonies of A. domesticus to determine if any sub-lethal effects occurred as a result of exposure to oil vapors. Sweep-net sampling collected four times more insects than vacuuming and collected significantly more insect taxa (p = 0.0005). Oiled marshes had increased insect populations compared with non-oiled areas (p = 0.0495). Over 108 insect morphospecies were collected in the marsh. C. pilosas foraging behavior was drastically reduced by oil presence (p < 0.0001) though oil did not usually increase mortality. The time for 50% and 100% mortality to occur in A. domesticus was significantly less when exposed to direct contact with oil (p < 0.0001 for both 50% and 100%) and indirect contact with oil (p = 0.0053, p = 0.0005 for 50% and 100%, respectively). House crickets exposed to oil vapors showed reduced adult life spans, longer time to maturation, and changes in resistance to parasites when compared with controls. All these data indicate oil exposure can change insect populations, rates of mortality, and behaviors

Tomato spotted wilt tospovirus (TSWV), a thrips-borne plant virus, occurs globally in economically damaging levels in agricultural, ornamental, and greenhouse crops. In North Carolina, TSWV is vectored primarily by the tobacco thrips, Frankliniella fusca (Hinds), and the Western flower thrips, F. occidentalis Pergande, both of which can acquire and subsequently transmit TSWV only by feeding on infected foliage as young larvae. Females oviposit in suitable plant tissues; therefore, only those plant species susceptible to systemic infection and with the ability to support reproduction by vector species have the potential to be important sources of virus inoculum. We conducted systematic plant surveys to determine the incidence of TSWV and the relative abundance of thrips vector species on summer annual and perennial plants commonly associated with susceptible crops in North Carolina. Frankliniella occidentalis was the most abundant vector and comprised >75% of vector species collected from 18 wild plant species during the summer and fall of 2002. The number of F. occidentalis and F. fusca larvae collected from plant samples, whose presence indicates a plant?s suitability for reproduction, varied significantly among the species sampled. The plant species yielding the largest collections of immature F. occidentalis were tall morningglory (Ipomoea purpurea), carpetweed (Mollugo verticillata), sicklepod (Cassia obtusifolia), and Palmer?s pigweed (Amaranthus palmeri). Plant species most suitable for F. fusca reproduction included Florida pusley (Richardia scabra), M. verticillata, and ivyleaf morningglory (I. hederacea). During surveys of wild plant species in or adjacent to highly TSWV-infected crop fields, TSWV was documented at 16 of 17 locations (94.1%) and in 14 of 30 weed species (46.7%). Estimated rates of infection were highest in I purpurea (6.8%) and I. hederacea (1.9%). Mollugo verticillata returned an unusually high proportion of marginally TSWV-positive samples and conservative estimates of infection rate were 0.5%. However, the actual importance of this species as a TSWV reservoir may be much greater, as liberal estimates (assuming marginal samples were indeed TSWV-infected) indicate an infection rate of 5.4%. These findings document that only a limited number of summer annual or perennial weed species are potentially important TSWV reservoirs or support high levels of vector reproduction in North Carolina. The temporal characteristics of vector abundance and dispersal were documented in the summer and fall of 2002 using aerial sticky traps surrounding 9 agricultural fields. Of vector species captured, 83.3% were F. occidentalis, 11.9% were F. fusca, and the remaining 4.8% were Thrips tabaci Lindeman. The timing of F. occidentalis dispersal, as indicated by mean cumulative proportions of F. occidentalis caught on traps, varied significantly among locations. Patterns of fall dispersal were unrelated to senescence of summer annual weeds, cultivation practices, or the first freeze date. Temporal patterns of TSWV movement were monitored with sentinel tomato plants (Lycopersicon esculentum var. ?mountain fresh?) at the same locations where aerial sticky traps occurred. TSWV-infected sentinel plants were recovered, sporadically and unpredictably, over a 3-month span in the fall of 2002. TSWV movement was not related to thrips dispersal, cultivation date, or summer weed maturation.