- Author: Kathy Keatley Garvey
Back in April of 2021, we wrote: "They're out there, and you don't have to crane your neck to see them."
The topic: crane flies. They're often mistakenly called "mosquito eaters" or "mosquito hawks." They're neither. They're members of the family Tipulidae of the order Diptera (flies).
Lynn Kimsey, director of the Bohart Museum of Entomology and UC Davis distinguished professor of entomology, emphasizes that crane flies don't eat mosquitoes. "In fact, adult crane flies generally don't eat at all," she points out. "Their entire brief adult lives are spent searching for mates and laying eggs." Crane flies are attracted to lights at night and you may find them around your porch light.
"Adult crane flies emerge from the soil beneath turfgrass, pastures and other grassy areas in late summer and fall," according to the UC Statewide Integrated Pest Management Program, part of the UC Agriculture and Natural Resources. (We've sighted them only in the spring.) "The adults have very long legs and resemble large mosquitoes. Females mate and lay eggs in grass within 24 hours of emerging. Eggs hatch into small, brown, wormlike larvae that have very tough skin and are commonly referred to as leatherjackets.The leatherjackets feed on the roots and crowns of clover and grass plants during the fall. They spend the winter as larvae in the soil; when the weather warms in spring, they resume feeding. During the day larvae mostly stay underground, but on damp, warm nights they come to the surface to feed on the aboveground parts of many plants. When mature, the larvae are about about 1 to 1½ inch long. Around mid-May they enter a nonfeeding pupal stage and remain just below the soil surface. In late summer, pupae wriggle to the surface and the adults emerge. There is one generation a year."
It's not easy to photograph these slender, gangly, goofy-looking insects that resemble cartoon characters. If you spot them, they take flight. If you shadow them, they vanish. If you creep up upon them, they creep faster. If you say "Oh, well, Mr. Crane Fly, I didn't want to take your picture today anyway!"--that's when they pose.
I captured this image of a crane fly taking a break in a Spanish lavender bed on May 23, 2023. The morning light was just right.
- Author: Lauren Fordyce
Lately you may have seen some large, leggy insects bumbling around on your home, bouncing off walls and ceilings. What are these?
While many people call them “mosquito eaters” or “mosquito hawks,” they are actually crane flies. And unfortunately, they do not eat mosquitoes. Many reports claim that they bite or sting, and this is also false. The adults are harmless and many species don't even have mouthparts to feed at all! However, their larvae can be pests of lawns and turfgrass.
Larvae are to 1-1/2 inches long, brown, and wormlike with very tough skin. They may resemble white grubs, but crane fly larvae do not have legs. The majority of lawn damage from crane flies is seen along the Pacific Northwest coast. In California, damage has been found mostly in Humboldt and Del Norte counties, rarely in warmer, dryer inland areas of the state. Although, wet springs and waterlogged soils are usually associated with a higher populations of crane flies.
You can prevent crane flies in your lawn by properly irrigating and fertilizing. Adjust irrigation systems during rainy periods to avoid overwatering. Remove excess thatch and aerate you lawn to improve drainage. Reduce shady areas by pruning back tree branches to allow more light to reach the grass during the early morning and late afternoon.
Find out more about crane flies by reading the UC IPM Pest Notes: Lawn Insects.
Learn how to control mosquitoes around your home by visiting the UC IPM Pest Notes: Mosquitoes.
Warmer weather means many pests are flying and joining you indoors while you shelter-in-place or outdoors while you are getting some exercise or keeping connected yet socially distant from the neighbors.
Lately you may have seen some large, leggy insects bumbling around on your walls and windows. What are these? While many people call them “mosquito eaters” or “mosquito hawks,” they are actually crane flies. And unfortunately, they do not eat mosquitoes. These insects may be a nuisance when you find them in your home, but the adults are basically harmless. Although the adults are not particular pests of importance, the larvae can be pests of lawns and turfgrass. You can read more about crane flies in a previous blogpost and learn about ways to manage crane flies in our Pest Notes: Lawn Insects.
Mosquitoes on the other hand are pests to be concerned about. Mosquitoes pierce through our skin with needle-like mouthparts, sucking out our blood. In doing so, they could also be transferring disease-causing pathogens. Find out more about protecting yourself from mosquitoes and reducing mosquito breeding sites in the UC IPM Pest Notes: Mosquitoes.
Last Saturday, UC IPM staff greeted a swarm of visitors at their Picnic Day booth. Picnic Day, UC Davis' annual Open House event, invites people to visit the campus and interact with fun and educational exhibits. UC IPM has participated in Picnic Day for more than a decade and this year attracted visitors to their booth with live insects like hissing cockroaches, a termite colony, and crane flies. UC IPM staff answered many questions about pests, pesticides, and cleared up misconceptions about some common insects.
What did we talk with people about?
Ant control, indoors and out
Beneficial insects and spiders (natural enemies)
Cockroach identification
Invasive pests: why you shouldn't move firewood
Bed bugs
How to tell the difference between green fruit beetles and the invasive Japanese beetle
Lady beetle (ladybug) life cycle- don't squish the “good bugs!”
Controlling termites around the home
How to tell ants and termites apart
Snail and slug damage
Mealybugs on cactus and succulents
Many people confuse jumping spiders with black widow spiders
Crane flies are NOT giant mosquitoes, nor do they eat mosquitoes
You don't have to attend Picnic Day to get this information! The UC IPM website is available anytime for help with home, garden, turf, and landscape pests. You can also contact your local UC Master Gardener Program or UC Cooperative Extension for assistance identifying pests and finding solutions.
These insects are actually called crane flies, and sorry-- they don't eat mosquitoes.
They also don't bite or sting but can be a nuisance pest for some. In reality, crane fly larvae are a pest of turfgrass.
The best way to deal with crane flies is prevention. Learn how to prevent crane flies in your home and landscape by reading the blogpost ‘Mosquito Hawks' in Your House? Or by visiting the UC IPM Crane Fly web page.