Weekly Update – June 5th – Mosquito Numbers Remain High, First Positive WNV Sample
June 13, 2023
NMCAW: Meet Allison and Kevin from MMCD’s Maple Grove Facility
June 22, 2023
Mosquito numbers are declining as we head into mid-June and have dipped below the 10-year average.
For the second week in a row adult mosquitoes are trending above average, although the total is flattening.
Every Monday night starting in mid-May through September, the Metropolitan Mosquito Control District sets out a variety of mosquito and black fly traps throughout the district and employs a network of sweep net collections done by employees and volunteers. Any insects collected are brought back to our lab on Tuesday to be identified throughout the week with maps published to show current mosquito and black fly activity.
After a lot of areas in the red (300+ mosquitoes per trap) for the mosquito surveillance week of June 5th, we saw a slight decline in most traps this week with only 6 CO2 traps collecting over 1,000 mosquitoes compared to 19 the week before. Lack of rain over the past few weeks is one factor that has contributed to lower mosquito numbers as much of Minnesota has been abnormally dry for the third consecutive year.
According to MMCD assistant entomologist Dr. Scott Larson, " There’s still plenty of mosquitoes, in general, but their numbers lessened last week. We are now below the 10-year average by ~150 human-biting mosquitoes per CO2 trap (on average). Spring Aedes are still hanging on out there, and the Cq. perturbans numbers are low but were more common in the North and East regions."
Cattail mosquitoes (Coquillettidia perturbans) are continuing to emerge throughout the District as we head into their peak time of year. Typically cattail mosquitoes are at their highest around the 4th of July after which they slowly decline. Our entomology lab predicted this year will see lower than average cattail mosquito numbers.
Here are the mosquito trap counts from last Monday, June 12th:
Risk of tick-borne disease remains high. Mosquito-borne disease risk increases throughout the summer.
June is a high-risk month for the transmission of Lyme disease because Deer ticks (black-legged ticks) in the nymph stage are active. The Minnesota Department of Health offers a variety of tips and suggestions to lower your risk of tick-borne disease.
The risk of mosquito-borne disease tends to increase as we head into mid- and late-summer as the mosquitoes that vector diseases like West Nile virus and La Crosse encephalitis become more active. Hot weather can increase their activity and the past two weeks have seen warm, dry conditions.
There were no new positive samples of West Nile virus in adult mosquitoes tested this week.
Ensure you are protecting yourself from mosquito-borne disease by using bug spray, wearing long, light, and loose clothing, and avoiding the peak feeding times of dawn and dusk.
June 18-24 is National Mosquito Control Awareness Week!
While every week is all about mosquitoes here at MMCD, we are excited to join with districts all around the country to observe National Mosquito Control Awareness Week! To celebrate, we will be sharing some safe DIY mosquito control tips, interviews with some of our staff, product recommendations for your next camping trip, and much more!
Stay tuned here on our website and at all of our social media pages for the latest:
