Project Overview
Annual Reports
Commodities
- Animals: bovine, swine
- Animal Products: dairy
Practices
- Pest Management: biological control
Proposal abstract:
Pupal parasitoids are often used as sustainable biological control options for filth fly pests on livestock operations. Filth flies, such as stable flies (Stomoxys calcitrans Linnaeus) and house flies (Musca domestica L.), are mechanical vectors of disease and can cause pain and losses of condition to livestock. Conventional control of these pests has relied on high doses of various insecticides. Filth fly pests are becoming increasingly resistant to many licensed insecticides and the increase of chemical use is harmful to the environment. The purpose of this project is to improve the use of pupal parasitoids of filth flies as part of a sustainable biological control program on livestock operations. Though used often, there is only limited empirical information on the microhabitat preferences and protocols for release of Spalangia cameroni Perkins (Hymenoptera: Pteromalidae), a common parasitoid in Florida, that will assure their effectiveness. The goal of this research is to (1) define the odor cues which influence host location by filth fly parasitoids, (2) assess dispersal to host sites from release locations in the field, and (3) outreach and extension activities to increase the operator awareness of biological control of filth flies. Impacts of this research include increasing the effectiveness of the parasitoids, reducing exposure of humans and animals to toxic insecticides, managing insecticide resistance by improving sustainable biological control options and ultimately reducing cost and increasing the use of these parasitoids to manage filth flies.
Project objectives from proposal:
Olfactory cues are important for orienting parasitoids towards their hosts (Vinson 1976). Initial experimentation with a related wasp, Muscidifurax zarapter Giralult and Sanders, showed that females were attracted to pupae but not manure mixed with pupae (McKay and Broce 2003). It is not known if females rely upon odors produced by host larvae or the interaction of larvae and manure to orient them initially to locations where pupation may occur. Based on my preliminary research (see Experience and Roles) assessing microhabitat preferences, my central hypotheses are that odor cues emitted from developing filth fly larvae provide olfactory stimuli which attract emerged S. cameroni to host locations and field parasitism levels significantly and quickly decline as distance increases form release sites.
The goal of this research is to (1) define the odor cues which influence host location by filth fly parasitoids, (2) assess dispersal to hosts sites from release locations in the field, and (3) increase the operator awareness of biological control of filth flies.
Goal (1): Define the odor cues which influence host location by filth fly parasitoids
1) Objective 1: To assess the attraction of S. cameroni to the larvae of house flies at different concentrations. Once emerged from a host as an adult, the understanding of the attraction to hosts for oviposition by the parasitoids is limited. Analysis of responses to concentrations of immature house flies will begin to elucidate whether concentration of hosts are important considerations for field releases.
2) Objective 2: To assess the attraction of S. cameroni to manures of three different farm animals and the attraction to the interaction between developing larvae in the manure. Samples of manure and other common fly breeding substrates will be analyzed for parasitoid responses to odors. Analysis of responses larvae and substrate will demonstrate attraction to odors associated with hosts and substrates which will be useful for improvement of biological control programs.
Goal (2): Assessment of dispersal to hosts sites from release locations in the field
3) Objective 3: To assess dispersal range of S. cameroni when hosts are immediately present at many distances and when hosts are not immediately available. Multiple release mechanisms have been suggested for implementation of a biological control program for filth flies. However, the extent of dispersal to hosts from release sites has only been speculated. Data on dispersal of S. cameroni is limited to studies conducted on Scandanavian pig farms. Determining the limit of dispersal from these release sites will help managers determine where releases need to occur and improve release strategies.
Goal (3): Outreach and extension activities to increase the operator awareness of biological control of filth flies.
4) Objective 4: Development of an extension publication to assist farmers in the use and selection of parasitic wasps for filth fly control: A useful guide will be developed for livestock farmers on the acquisition, implementation, and uses of parasitic wasps for control of filth flies. A booth at the Florida Small Farms Conference will be used to distribute this information to farmers.