Weekly Update – May 28 – Rainy Conditions Make Mosquitoes Hard to Collect
May 30, 2025
It's been a quiet season for mosquitoes so far in the Twin Cities.
Adult mosquito populations remain very low as we head into June.
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.
For the fourth week in a row the number of adult mosquitoes collected in MMCD carbon dioxide-baited traps has been significantly below the 10-year average. Unlike the same time in 2024 and 2023 we have not seen the surge of spring Aedes mosquitoes that led to high trap collections and high call volumes in the past two years. According to MMCD Entomologist, Dr. Scott Larson, most of the mosquitoes we are finding currently are spring Aedes, but in much lower numbers than previous years. Larson says the numbers of Aedes vexans, our most abundant summer nuisance mosquito in most years, are "remarkably low."
While we expect the overall number of mosquitoes to gradually increase, the cool, windy temperatures forecasted for tonight means our traps going out this week and being collected tomorrow may not catch very many. Warmer, wetter temperatures forecasted for later in the week could speed things along.
Below are maps showing mosquitoes collected in CO2 traps over the past two weeks (click to enlarge):
MMCD collected and recycled over 1,600 tires at our Scott and Carver County drop-off event last week.
One of the important methods to reduce mosquito-borne disease is doing "source reduction" or removing human-made habitat that can become hospitable to mosquito larvae. One of these sources is waste tire piles, which collect water that becomes warm and stagnant and makes a great habitat for the larvae of some of the more dangerous mosquito species that can carry diseases like La Crosse encephalitis.
Last week MMCD held a drop-off event where residents could call ahead and make an appointment to drop off up to 20 tires per household. The result was a big success and we removed over 1,600 tires from the environment! Recycled tires become playground equipment, landscaping materials, and other uses to prevent them from ending up in landfills.
Check out a photo of the final pile below. This week we will be hosting a similar event in Rosemount for Dakota County residents. Check out our tire recycling webpage to learn more.
Summer events continue into this weekend - stop by and see MMCD!
We are going to be busy this weekend with more exciting events! Check us out at the following starting mid-week:
- Hennepin County Fair - Thursday, June 12th - Saturday, June 14th
- Father Hennepin Festival Parade - Friday, June 13th
- Little Canada Touch-a-Truck - Saturday, June 14th
- Juneteenth Roseville - Saturday, June 14th
- St. Louis Parktacular Parade - Saturday, June 14th
We will have giveaways like tattoos and pencils and most events will feature live mosquito larvae to interact with and learn about!
