Crane Flies in San Diego: The Harmless, Horrifying Insect That Just Will Not Go Away
Crane flies are extremely annoying but not dangerous to humans or pets.
Let’s be honest: if you have lived in San Diego County for any amount of time, you have probably had a run-in with a crane fly—and you probably did not enjoy it. These leggy, oversized mosquito look-alikes seem to come out of nowhere, banging into your walls, hovering erratically around your porch light, or worse, dive-bombing your head when you least expect it.
Most locals refer to them as “mosquito hawks” or “giant mosquitoes,” and while neither name is technically correct, they have certainly earned their reputation as one of the most irritating seasonal pests in the region.
Why Everyone Hates Them
It is not just their looks—although let’s be real, crane flies are nightmare fuel for anyone even mildly squeamish about bugs. With their long, wobbly legs and clumsy flying, they come off as the gangly creeps of the insect world. They are not dangerous, but try explaining that to someone who just had one flail across their face during dinner or who has had one get tangled in their hair.
The fact that they look like they could bite your arm off does not help. People assume they are giant mosquitoes, and while they are technically harmless, that does not make them less of a nuisance. They swarm around lights, slam into windows, and somehow always manage to find their way inside—even when your doors and screens are supposedly shut tight. Crane flies seem to be especially brainless and surprisingly aimless in their ventures.
Their presence is a seasonal occurrence—especially in spring and early fall—but that does not make it less frustrating. For a few weeks each year, it can feel like your home and yard has turned into a set from a low-budget horror film.
Environmental Impact: A Mixed Bag
While adult crane flies are mostly just annoying bugs, their larvae—called leatherjackets—can actually cause real damage. That lush San Diego lawn you have spent money and weekends maintaining? Leatherjackets live underground and feed on the roots of grasses and other plants. When their numbers spike, you can say goodbye to your pristine landscaping.
In more natural environments like wetlands or streambeds, they do have some ecological value. The larvae help break down decaying matter, which recycles nutrients into the soil. But in urban and suburban settings, they are more of a landscaping headache than anything else. Brown spots on your lawn, stunted plants, and costly yard repairs? That is what you get in exchange for hosting these undesirable bugs in your soil.
Pest Control and Prevention
A close up look at the Crane Fly.
If you are looking to avoid a crane fly invasion in your home, your best bet is to go on the offensive before they show up. Dim or turn off outdoor lights at night—crane flies are practically light-seeking missiles. Check your window screens, door seals, and vents for gaps, because they will find their way in through the smallest openings. Crane flies that make it inside our home usually followed us inside when opening and closing external doors so exercise caution when coming and going.
Inside your home, the best way to deal with them is to catch and remove them. Swatting works, but it is messy; scooping them up with a cup and tossing them outside is less gross in my opinion. Just try to not waste your time panicking like we did when we first encountered these little beasts—crane flies are not dangerous, just extremely irritating.
For yards, integrated pest management techniques can help with larvae. If things get bad, you may need to treat your lawn with nematodes or other biological agents to keep the population under control. It is not always cheap, but it is better than watching your landscaping get devoured from underground.
Bottom Line
Crane flies are not the worst pest we deal with in San Diego, but they might be the most unnecessarily dramatic. They do not bite, they do not sting, and they do not carry disease. But they make up for all of that by being wildly obnoxious, creepy, and impossible to ignore.
So, while experts will tell you they are harmless and even beneficial, most locals know the truth: crane flies are just one more thing we put up with for the privilege of living in beautiful Southern California.
