Category Archives: Biology

Eliminate mosquitoes by eliminating stagnant water

The most effective, cheapest way to control mosquitoes is to eliminate the standing water that larvae need to develop. A dry yard doesn’t have mosquitoes. It’s really that simple. Below is a list of objects to get rid of or dump regularly. Please share with your neighbors.

1. Gutters

This is at the top of the list because almost all houses have gutters and almost all homeowners hate to clean them out. Check for blocked gutters weekly if you have a lot of trees nearby. If gutter status is hard to see, buy a drone to facilitate inspections. If you can’t afford a drone just get an extra-long, telescoping selfie stick for your smartphone.

2. Flexible downspout extenders

Flexible downspout extenders are almost perfect for breeding mosquitoes — the ridges hold water and trap organic matter, the black absorbs heat from sunlight (thus speeding development), and female mosquitoes of several species just adore ovipositing inside plastic objects. They are especially bad if nestled in shrubs and ground cover. Note that they hold water even if they are sloped downward. Get rid of them. All of them.

3. Tarps

If you leave a tarp in your yard, you’ve created lots of nooks in which water and debris will accumulate. I frequently see tarps covering soggy logs that owners seem to have no real intention of ever splitting and burning. I think people view tarps as cloaks of invisibility, magically hiding loathsome to-do items from spouse.

4. Kid equipment

Sandbox toys, sleds, wagons, and kiddie pools seem as if they were specifically designed to breed mosquitoes. I.e., even when stored upside down they have nooks that collect enough rainwater to breed mosquitoes. Store them in the garage. If you think covering them with a tarp will work, please see #3.

5. Bird baths

Everyone should have a bird bath. But if you do, you need to either have a water bubbler/agitator (mosquitoes hate that) or you need to kill the larvae by adding granules of Bacillus thuringiensis var israelensis (abbreviated, Bti). Bti is extremely effective: you can add it a container that has thousands wriggling of larvae (see movie) and they will all be dead within hours. Just add it every two weeks and your bath will always be mosquito free. But don’t forget — make yourself a smartphone reminder or write on paper calendar.

Bird bath next to purple coneflowers

6. Trash and recycling bins

If you can’t store your trash and recycling containers under a roofed area, keep a lid on them. I found the ones below behind a local church. Tens of thousands of larvae within.

Recycling bins with stagnant water

7. Watering cans

Watering cans are rarely transparent so you can’t see the mosquito larvae inside, but they are present if you leave them around the yard when it’s been raining a lot. Store them empty, in garage.

8. Wheelbarrows

Just keep them propped up vertically so they don’t accumulate rain water. Or drill holes.

9. Rain barrels

Just put screening over the top. Or add Bti every other week. I don’t recommend adding mosquito-eating fish because they die when water level gets low (plus the fish suffer before dying).

10. Pot saucers

Pot saucers are unneeded outside so it’s easy to eliminate them. If you like them for decorative reasons you’ll need to add Bti regularly. It’s better to just get rid of them because you’ll eventually forget. You know you will.

Other places where mosquitoes breed

Below are photographs of stagnant water I’ve noticed around my town. On my list of photographs to add: bromeliad, pool cover, bottle cap.

How to protect yourself from ticks

I spend a lot of time outside, sometimes face-down in the weeds trying to get a photograph of something small. So I have some opinions about tick prevention and thought I’d share.

blacklegged (deer) tick on sock
Ixodes scapularis
  1. Spray or soak shoes, socks, pants, shirts, hairband, hat, etc., with permethrin (buy online or at outdoor stores), then let dry before you using. Chemical only slowly washes out so you only need to reapply every 5th laundering or so (or after 5 months if you don’t wash your clothes). Spray your backpack with permethrin, too, because you likely set that on the ground during breaks. Do not spray permethrin on your skin. You can also buy clothing that comes pretreated with permethrin.
  2. Spray your clothes and skin with DEET, picaridin, para-menthane-3,8-diol, IR3535, or 2-undecanone. DEET really is the best. Note that “pure” oil of lemon eucalyptus (extracted from Corymbia citriodora) is not currently recommended by the CDC; the oil has small, variable levels of para-menthane-3,8-diol but apparently not enough. All of these repellents do not last like permethrin so reapply every few hours. Do not spray DEET on anything plastic (it will melt).
  3. Be suspicious of “natural” or “organic” concoctions that claim to effectively deter ticks. If one of these recipes actually works the CDC would recommend it. I’ll update this page when that happens. Similarly, avoid apps, crystals, and dietary supplements. If you need help convincing a friend to just use DEET (it’s super safe), mention that DDT is a different chemical that just happens to start with the same letter. DEET is also gluten and GMO free.
  4. Wear light-colored clothing so you can better see ticks. Like this person. Note that this strategy fails with tick larvae because they just too small to see unless you are wearing something pure white and have really good vision.
  5. Tuck your pants into your socks. Like Kanye West. You can even buy tick socks that are treated with permethrin and have a tight weave that prevents larvae from burrowing through the fabric.
  6. Wear tall, light-colored, glossy boots that ticks can’t easily climb. I suspect that larvae and nymphs can still climb glossy surfaces, though. I own a pair of Muck Boots and they have a neoprene surface that I suspect ticks can easily scale. I’m considering switching to something like a Gumleaf boot.
  7. Buy some gaiters and treat them with permethrin. Some gaiters are even designed to keep out ticks. Some even come in lime green. (NB: Lyme disease is named after Lyme, CT.)
  8. Buy some arm sleeves. Like gaiters, you can even buy ones that are already infused with permethrin.
  9. Shave your legs.
  10. Keep checking for ticks as you hike. If you are hiking with others, scan them for ticks, too.
  11. Keep a roll of duct tape handy so that you can easily remove ticks. Travel-sized lint rollers are good, too, and easily attach with a carabiner to a backpack.
  12. Put your field clothes into quarantine when you come home. Ideally, launder them immediately. Ticks can wander off of clothing and backpacks and show up later.
  13. Get naked and check for ticks. Everywhere. This is a really good reason to get a girlfriend or boyfriend even if you’re not really into them. Don’t tell them that.
  14. If you have limited neck mobility, invest in a nice automotive inspection mirror so you can see all the various parts of your body you never look at. You can even buy lighted ones. You can also use a selfie stick and a smart phone, but that’s risky if you accidentally forget to delete the photographs and video.
  15. You probably don’t want to know this but ticks are fond of lodging in ears. Get yourself an otoscope if you feel something in there. You can even buy phone attachments to get pics.
  16. If you find a tick that is attached, take a photograph (like this) then remove the tick. Carefully. I have a Tick Key (see one in action) but there are lots of types. Then take photographs of the bite location and of the tick. If you live in Pennsylvania, send the tick out for free testing. If you live elsewhere, put the tick in vodka or in the freezer in case you need to get it tested later.
  17. Take a long hot bath with a lot of soap. Ticks are hardy but you might dislodge an unattached nymph that somehow got past your first-line defenses.
  18. Once you are de-ticked and clean and have the laundry running, post photograph of tick on iNaturalist so you can get an identification. Here are the ticks of North America on iNaturalist. You can also send pics of ticks to TickEncounter for ID.
  19. Monitor the attachment spot closely. If a red spot appears, take daily photographs with ruler in frame so that doctor can assess progress of redness. Here are pics of Lyme rashes. You can even mark the progress with a Sharpie. There are plenty of other diseases transmitted by ticks, though, so don’t rely on rashes.

Alternative lawn signs for Mosquito Shield

Mosquito Shield is just one of dozens of companies that spray pyrethroids to kill mosquitoes. Homeowners typically pay $800 per summer for treatments spaced every 21 days and, as part of the deal, agree to feature a sign in their yard for the season.

Two types of people have these yard signs. The main category is homeowners who fully understand that pesticides have bad environmental effects but who simply don’t care. These are likely the same people who knowingly drive with their high beams on at night (“It’s safer for ME!”). And then there are people who were duped by the pesticide companies into believing pyrethroids kill only mosquitoes.

To better reach this second type of person as well as those who are interested in mosquito sprays but are still on the fence, I’ve fabricated six signs that highlight the fact that pyrethroids kill other animals:

All the signs are fairly self-explanatory except for perhaps the Bird Shield one. Pyrethroids don’t kill birds directly but many species depend on insects and spiders to feed themselves and their young. So when you hire Mosquito Shield to nuke your yard every three weeks you are reducing the numbers of birds that can survive in an area.

I realize that none of the above signs is going to be used by an actual pesticide company. Their business model is to obfuscate about the effects of pyrethroids. Indeed, most companies try to hide the fact that their mosquito sprays even contain pesticides. That’s why the government (federal and/or state) should require companies to clearly indicate the active ingredient of the spray. Here’s how it could (should) look, thus allowing curious neighbors to Google the chemical and be horrified.

Pyrethroid sign for Mosquito Shield

If you are an influential part of a local government, please consider enacting an ordinance that requires disclosure of the pesticide name on signs.

If you need an individual sign for your a presentation, here are some image files: fireflies, butterflies, bees, spiders, fish, birds.

Please share this page on your neighborhood social media to get the word out. These companies are spreading in popularity and it’s horrifying.

More details here.