Mc Callister Talk
McCallister Talk 7/24/08Gary - Mesa State College - Biology professor -involved in mosquito control for 15-20 years.
Zane - Grand River Mosquito Control District for 11 years.
Gary - IPM for mosquito control still being "invented." Integrated Pest Management uses multiple methods, not just one. Needs to be tailored to your area and to your pest. 1700 species of mosquitoes, each of which has variations in life cycle and habits. Generally, need still water. Poor swimmers, need to have air tube clear. Filter feeders. Stop feeding a few hours before pupating. Rate of growth depends on temperature. Pupae stage lasts hours to days. Males and females have different anatomies and habits. Nectar feeders (plant juices). Can't break through cell walls. Not pollinators. Only females get blood meals after mating to allow for egg development. Mosquitoes can fly well - up to a mile to seek blood meal or breeding site. Some Ochlerotatus go 10 miles. Almost have to use "battle plans" to "herd" them to get them by spray. Many people believe spraying for mosquitoes is highly inefficient. However, some areas too wet to handle by larviciding alone. Early on in their program, they decided to focus on larvae. Controlling breeding sites and attacking larvae can eliminate a higher proportion of the population. Try to minimize damage to non-target organisms. Mesa Co. did 95% larviciding. Grand River District now bigger, cannot be done in the same way. Can also target breeding sites by time - you will learn the site patterns as you go - which time of year or under which conditions a site will produce mosquitoes. Also have to constantly look for new sites. Rank breeding sites by Site Annoyance Potential (SAP). Number of broods, larvae per dip, etc. Can target your efforts toward most productive sites. Egg to adult development 7-10 days (disputes 4 days). Prioritize sites by breeding potential, not time. (Go back to #1 SAP, not the one that's been missed 11 days).
Zane - Spends $250,000 per year on larviciding, only about $12,000 on adulticiding in a bad year. SAP - size of site, number of broods per season, proximity to population, larvae per dip. Mosquito Control to Fit Your Town - Shoegren. (Out of print - get copy from Zane?) IPM - use all "tools" in your "toolbox." Adulticides useful, though used sparingly. Mechanically - drain and dig ditches; Chemically - pesticides; Biologically - larvicide. Best tool - Bti - used almost exclusively. Bti always kills larvae, but needs reapplication frequently. Vectobac G (larger granular)- floats longer Vectobac CG - penetrates heavy vegetation. Don't use briquets. Bs (Vectolex) specific to Culex, more expensive, subject to misapplications. If a field dries and wets, they use Altocid (growth regulator). Keeps larvae as food source in the water, but pupae don't hatch functioning adults. Uses briquets in storm drains, pellets on fields. But very expensive. Starting to use Agnique but not happy with it. Salty soil breaks it down quickly. They use granules to avoid complication of two different formulations.
Very cautious about fighting with people who won't change irrigation practices. Don't make enemies.
Hiring - uses Mesa State students and provides internships (college credit). Very flexible with hours. Starts them at $12 per hour. Gives more per year. 73 square mile district. 8 full time field workers plus field manager plus office manager. Budget $940,000 per year. Operating expenses $450,000 per year.
Doesn't use water-based insecticides from the air - low kill rate. Have had to spray 3 times so far this summer - may have to do one more this summer. Some summers don't spray at all. Trap thresholds 50 per trap. He's upset at more than 15 per trap. Used to try to set thresholds under 10. Trap data over the years have allowed them to predict timing of outbreaks. 40 trap sites per week (plus now 5 gravid traps). Trapping budget about 10-12% of budget. 4-5 hours per week labor cost. No spray trucks. Cost is in labor. You don't kill mosquitoes with chemicals or equipment, but with knowledge.
grmcd.net - website
Gary - No resistance to Bti so far in mosquitoes, but other insects have started developing resistance. Gary will begin testing to see how/if mosquitoes develop resistance
Zane - Half their district was annexed in the past year. "Chasing their tails" trying to fight mosquitoes. Sites identified by GPS. Handheld units are used to enter data, which is shipped back to the database. Goal is to map every site. Takes a couple of years to develop. Sites are prioritized by SAP so that worst ones can be addressed (chopped up into regions for each team. Electronic Data Solutions - has good program for database management.
Gary - running mosquito control on a shoestring.
Thresholds - phone calls re/ mosquitoes go up as trap counts go up. No calls under 10, 20-25 "intolerable." When they spray now, they target the vegetation around the river bottom - harborage. Current threshold now 50 Culex/75 total.
Aerial spray - done in morning to take advantage of down draft of cold air. Costs $2500 per thousand acres.
Notification - Doesn't spray populated areas. Phone list of people who want to be notified (about 25 people), post notices on walking trails in affected areas. Clears out area physically before spraying. No mass media. Signs day before spray.
Training - Zane and Gary would be willing to help with training. Usually 2-3 days plus followed two weeks in the field.
