Chris Pritsos

Chris Pritsos

Chris Pritsos

Director of Nv Ag Experiment Station, Associate Dean of Research

Summary

Insecticides are commonly used worldwide, as well as Nevada, as a means of controlling insects which damage our crops and gardens and spread disease. Scientists are also always looking for more effective compounds. A concern with all insecticides is their specificity. Most insecticides are highly toxic to insects but also have some toxicity towards other species. The goal is to develop insecticides which are highly toxic to the desired target species and not very toxic to non-target species. One of the newest groups of insecticides are the neonicotinoids. They attack the nervous system of insects but are much less able to attack the nervous system of mammals.

These insecticides have become the most widely used in the world. Because of their versatility in application, they are used in a variety of farmland crops such as cereal crops, canola, potatoes and horticulture vegetable crops, fruits and vineyards. Neonicotinoids are also sold as garden sprays for flowers and vegetables. Recent studies however have shown that these compounds can be toxic to some non-target organisms, including honey bees and birds. Honey bee colony collapse has been attributed to the use of these compounds which appears to cause the bees to become disoriented. Migratory birds routinely stop in fields, pastures and waterways to re-fuel and rest before continuing on to their breeding or wintering grounds. Exposure to neonicotinoid contaminated food or water at these sites could have deleterious effects ranging from acute to non-acute toxicities including mortality, reproductive and flight navigation effects (similar to the honey bee phenomenon).

Migratory birds are protected by international treaty. Non-migratory birds such as the sage grouse, could also be effected by exposure to these compounds from the fields near their leks.

There have been very few studies to date which have looked at the effects of low-dose neonicotinoid exposure to avian species. There have been no studies which have examined the potential effect of neonicotinoid exposure on avian flight and bird migration.

Pritsos laboratory has developed a unique avian model capable of testing the effects of environmental exposures on avian flight and reproduction. This model can be used to mimic migratory flight behavior. We therefore propose to test the effects of two widely used neonicotinoid insecticides (Imidacloprid and Clothianidin) on flight and reproduction using our homing pigeon avian model. Exposed adults will be tested for reproductive success at environmentally relevant dosages and their offspring monitored for developmental behavior. Using GPS technology, exposed adults are tested for effects on flight. The Team also conducts studies to determine the ½ life of these compounds in the blood of these birds to determine how long it stays in their systems. This research provides important data about the safety of these insecticides to birds and may provide insights on their effects on honey bees.

Education

B.A.Occidental College, 1975
Ph.D. University of Nevada, 1982