Understanding What Attracts Crane Flies: Key Factors Explained

Crane flies are commonly mistaken for giant mosquitoes due to their similar appearance. However, unlike mosquitoes, crane flies don’t bite or spread diseases. So, you might wonder what attracts these harmless creatures to your lawn or garden?

Adult crane flies are primarily drawn to moist areas with high soil moisture for laying their eggs. Generally, this occurs in mid-September, and the larvae emerge in early October. Rainy fall conditions are ideal for the survival of both eggs and young larvae. As a result, you’ll often find them near waterways or other areas with plenty of moisture.

In addition to moisture, crane flies are attracted to decomposing organic matter and decaying vegetation. Their larvae, also known as leatherjackets, feed on these materials and sometimes grass roots. Eliminate or minimize these sources, and you can deter crane flies from invading your outdoor spaces.

Understanding Crane Flies

Crane flies, members of the family Tipulidae, are often mistaken for mosquitoes due to their long legs and slender bodies. However, they are actually part of the Diptera family, commonly known as true flies. There are about 15,000 species of crane flies worldwide, making them quite diverse.

Adult crane flies are easily recognized by their long legs which can break off easily, and they have a lengthier wingspan compared to other flies. Their antennae are also quite prominent, contributing to their unique appearance.

One interesting aspect of crane flies is that their adult stage is relatively short-lived. They typically only live for a week or two, spending most of their lifespan in the larval stage. Adult crane flies are attracted to light, which is why they can often be found near windows or outdoor lighting fixtures at night.

Since crane flies are drawn to lights, it’s important to consider how your outdoor lighting may be attracting them. Some tips to minimize crane fly attraction include:

  • Using yellow or sodium vapor bulbs, which emit wavelengths less attractive to insects.
  • Positioning lights away from doors or windows to avoid drawing them into your home.
  • Turning off unnecessary lights during dusk and dawn, when crane flies are most active.

Remember, crane flies are generally harmless and an essential part of our ecosystem. By understanding their behavior and attractions, you can minimize their presence around your lights and living spaces, while still maintaining a friendly environment for these fascinating insects.

Life Cycle of Crane Flies

Crane flies undergo a complete metamorphosis in their life cycle, which consists of four stages: egg, larva, pupa, and adult.

Eggs: Females lay their eggs close to water sources or in wet soil where larvae can easily access food resources once they hatch.

Larvae: The eggs hatch into larvae, which live in water bodies such as ponds and streams or in wet, soil-rich environments. They feed on decaying organic matter, plant roots, and small aquatic organisms.

As they grow, crane fly larvae molt several times. As they complete this stage, they search for a suitable location to pupate.

Pupa: The pupating stage involves the larvae forming a protective cocoon around themselves. They remain inactive during this time, allowing their bodies to transform into adult crane flies.

Adults: Once the metamorphosis is complete, adult crane flies emerge from their cocoons. Their lifespan is relatively short, lasting only about one to two weeks. During this time, they focus on reproducing, with females laying eggs to continue the cycle.

Now that you’re familiar with the crane fly life cycle, you can better understand what attracts these insects to certain environments. Ideal locations for eggs, larvae, and pupae to thrive play a major role in their development and ability to reproduce.

Habitat Preferences

Crane flies are attracted to a variety of habitats, but they typically prefer areas with moist soil and vegetation. They are commonly found in lawns, pastures, and along streams, where plants provide both shelter and food sources for their larvae. The Pacific Northwest in North America is home to many crane fly species.

You may often observe crane flies around your lawn, especially during late spring and early fall when they become more prevalent. Your lawn offers the perfect combination of moist soil and vegetation, making it an ideal habitat for these insects. Crane flies are particularly attracted to moist lawns with an abundance of organic matter.

Some examples of other habitats crane flies may be found include:

  • Wetlands
  • Forests
  • Marshes

Crane flies can tolerate a range of environments, but their preference for moist soil and vegetation is crucial for their success. For instance, in aquatic environments, crane flies are often associated with submerged and emergent plants. These areas provide the right conditions for their larvae to thrive.

In conclusion, understanding the habitat preferences of crane flies can help you be more aware of their presence and manage them effectively in your lawn or garden.

Feeding Habits

Crane flies, often mistaken for giant mosquitoes, have unique feeding habits depending on their life stage. As larvae, referred to as leatherjackets, they primarily feed on plant roots, particularly grass roots.

Leatherjackets serve as decomposers, consuming decaying plant matter as well as some living plant tissue. This contributes to their food sources, which include:

  • Grass roots
  • Plant roots
  • Decaying plant material

These larvae can have significant impact on turfgrass, making it crucial for lawn owners to be aware of their presence. Proper lawn maintenance, such as fertilization and irrigation, can help minimize damage caused by crane fly larvae, boosting turfgrass tolerance to feeding.

Adult crane flies, on the other hand, have a much different diet. They generally consume very little or no food at all. When they do eat, they tend to feed on nectar or other fluids to acquire nutrients.

In summary, crane fly feeding habits greatly vary between their larval and adult stages:

Life Stage Diet
Larvae Roots, plant material
Adult Nectar, fluids

Understanding these habits can help you manage crane flies effectively and maintain the health of your lawn or garden.

Impact on Lawns and Gardens

Crane flies can cause damage to your lawns and gardens. They lay eggs in moist soil, which then hatch into larvae, also known as leatherjackets. These larvae feed on the roots and crowns of grass, leading to the formation of brown patches in your lawn.

To prevent crane fly infestations and mitigate their impact, consider implementing these lawn care practices:

  • Regular aeration: This process helps reduce soil compaction, improving water penetration and root growth, making your lawn more resistant to damage.
  • Proper watering: Keep your lawn adequately watered, but avoid overwatering, as excessively moist soil attracts adult crane flies to lay their eggs.

Some common lawn and garden pests include:

  • Japanese beetles
  • Grubs
  • Sod webworms
  • Chinch bugs

Comparing crane flies to other lawn and garden pests:

Pest Damage Caused Prevention Method
Crane Fly Brown patches, weakened root system Regular aeration, proper watering
Japanese Beetle Skeletonized leaves, browning Pheromone traps, hand-picking, neem oil
Grub Dead grass patches Biological control (nematodes), preventative insecticides
Sod Webworm Irregular brown patches Natural predators, bacterial insecticides (Bt)
Chinch Bug Yellowing, dying grass Soap flushing, natural predator introduction, resistant grass varieties

By implementing proper lawn care techniques and remaining vigilant in monitoring for pests, you can minimize the impact of crane flies and other lawn invaders on your beautiful garden and lawn.

Crane Fly Pests

Leatherjackets, the larvae of crane flies, can be a major pest in certain areas. They are especially problematic for golf courses and field crops. Adult crane flies are often mistaken for mosquitoes, but they are actually harmless. There are two primary species that cause damage, the European crane fly and the marsh crane fly.

The European crane fly is an invasive species. These crane flies are known for their long legs and elongated, slim bodies. They lay their eggs in the ground, and the larvae feed on grass roots. This can lead to dead patches on lawns, golf courses, and even field crops. The European crane fly typically has one generation a year.

Marsh crane flies, on the other hand, have multiple generations per year. These crane flies are more recently found in the Pacific Northwest source. They are also referred to as European crane flies due to their similar appearance and damage patterns.

Here are some common features of crane flies:

  • Long legs
  • Elongated, slim bodies
  • Resemble mosquitoes, but are harmless

Crane flies are sometimes called mosquito hawks or mosquito eaters, although they do not feed on mosquitoes or their larvae source. In reality, adult crane flies do not pose a threat to humans.

To manage crane fly infestations in your lawn or garden, it is essential to understand their life cycle and habits. Reduce excessive moisture by improving drainage and regularly monitoring your irrigation system. You can also promote a healthy lawn with proper mowing, fertilization, and aeration practices. This will help to keep their population in check and reduce the damage caused by these pests.

Natural Predators and Bird Interactions

Birds are one of the primary natural predators of crane flies. They are attracted to bird baths and bird feeders, which provide an opportunity to feast on crane fly larvae hidden in the grass nearby. Other animals, like skunks, also feed on crane fly larvae.

Birds attracted to crane flies:

  • Robins
  • Starlings
  • Blackbirds

When setting up a bird bath or bird feeder in your yard, be sure to also accommodate for these crane fly predators. By attracting birds, you can help keep the crane fly population in check.

To make your yard more inviting for birds, consider:

  • Providing a variety of bird feeders
  • Offering fresh water in a bird bath
  • Planting bird-friendly plants and shrubs

Remember, these friendly birds not only help control crane fly populations but also add life and beauty to your outdoor space. Keep their needs in mind while setting up your garden or yard, and enjoy the mutual benefits as they assist with controlling crane flies.

Pest Control Methods

When it comes to crane fly control, using a combination of cultural practices and carefully chosen control methods will help maintain a healthy lawn and keep crane fly populations in check.

For starters, proper lawn maintenance and turfgrass selection can make your yard more resistant to crane fly damage. Mowing, fertilizing, and irrigating regularly in the summer, as well as choosing turfgrass that can grow well in your area’s sunlight conditions, will keep your lawn healthy and less vulnerable to pests OSU Extension Service.

For chemical control, insecticides are an option. A few types of insecticides that can be effective against crane flies are pyrethroids, clothianidin, and chlorantraniliprole. For example, a well-timed fall application (late September to mid-October) of these insecticides can prevent damage in the spring when larvae pose the greatest threat MSU IPM.

As an alternative to chemicals, you may consider using beneficial nematodes like Steinernema feltiae. These microscopic worms can naturally control crane fly larvae by infecting and killing them. Nematodes can be applied to damp soil in spring or fall for best results UC IPM.

To help decide between various control methods, here’s a comparison table:

Method Pros Cons
Cultural practices Non-toxic, promotes overall lawn health May not be enough for large infestations
Insecticides Effective if applied at the right time Chemicals can harm non-target organisms
Nematodes Natural, target-specific to larvae Requires proper application and conditions

Remember, always read and follow label instructions for any pest control products you use. By combining the right cultural practices and control methods in a timely manner, you can effectively manage crane fly infestations and keep your lawn in great shape.

Other Facts About Crane Flies

Crane flies are often mistaken for daddy longlegs due to their similar appearance, but they are actually quite different. Despite their intimidating look, crane flies are harmless creatures. Here are some other interesting facts about crane flies:

  • Crane flies are most active during late summer and early fall, although some species can be found in spring as well.
  • They are attracted to moist environments, which is where their larvae develop and grow.
  • These insects come in various sizes, and their body color can range from yellow to brownish-gray. Don’t be alarmed by their size; they pose no threat to humans.
  • When it comes to entering your home, crane flies may squeeze through window screens with their slender bodies. Ensure that your window screens are in good shape to keep them outside.
  • Female crane flies possess a needle-like appendage called an ovipositor, which they use for laying eggs. This might appear sharp, but it’s harmless and not stinger-like.

Some quick comparisons between crane flies and daddy longlegs include:

Feature Crane Flies Daddy Longlegs
Body shape Slender, long legs Oval body, long legs
Appearance Resemble giant mosquitoes Resemble spiders
Harmful No (harmless) No (harmless)

There are approximately 15,000 species of crane flies worldwide. Remember to always be gentle with these fragile creatures, as their long legs can easily break. Keep your home environment dry to deter these insects from coming indoors, and you can coexist peacefully.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Crane Fly from the UK

Subject: What’s this bug?!
Location: United Kingdom
June 27, 2013 2:18 am
Found in the UK, Summer. Looks very similar to a crane fly (daddy long legs), but it’s larger, and black/yellow!
Signature: Cory

Crane Fly
Crane Fly

Dear Cory,
This actually is a Crane Fly.  We cannot say for certain that it is  
Nephrotoma crocata which is pictured on Diptera Info, but it is very similar looking.

Thank you for you reply, I didn’t think I’d get one, but much appreciated!
Regards,
Cory.

Update:  June 2, 2018
Based on this new submission, we are now doubting our original species identification for this posting.  Based on images posted to Eakring Birds and on Diptera Info, we now believe this Crane Fly might be Ctenophora pectinicornis.

Letter 2 – Crane Fly from the UK: Nephrotoma crocata

Subject: What’s this flying bug?
Location: Wales
June 11, 2015 8:26 am
This flew into my house the other day and I’m stumped at what it is. It looks like a wasp/mosquito flying thing.
Signature: Inglebee

Crane Fly
Crane Fly

Dear Inglebee,
We believe we have correctly identified your Crane Fly as
Nephrotoma crocata, thanks to an image on the Alamy stock photo site, an identification we then verified on both Diptera Info and iSpot using the Natural History Museum’s UK Species Inventory.  Crane Flies are harmless and they do not sting.

Letter 3 – Crane Fly from India

Subject: I know it’s not a bird or a plane 😀
Location: Mumbai, India
December 12, 2014 10:55 am
But what is it? It was executing some low-to-the-floor flying manoeuvres and then settled down on my kitchen wall. Is it a wasp of some sort? What sort? Oh, also, my cats – normally enthusiastic bug serial killers won’t go near it. This is a good thing looking at that sting, but is is a clue?
Signature: – Lenny

Crane Fly
Crane Fly

Dear Lenny,
This beautiful insect is a Crane Fly, and we believe it probably derives some protection by mimicking the appearance of a stinging wasp.  India Nature Watch pictures an individual identified as
 Pselliophora laeta that looks just like your individual.

Sneaky! 🙂 Thanks so much.

Letter 4 – Crane Fly from Singapore

Subject:  Crane Fly?
Geographic location of the bug:  Singapore
Date: 06/10/2018
Your letter to the bugman:  Dear Bugman, love your site! Is this a Crane Fly?
How you want your letter signed:  Bug Hunter@SG

Crane Fly

Dear Bug Hunter@SG,
Thanks for the compliment.  This is indeed a Crane Fly, but we are not having any luck with a species identification.

Thanks so much. You guys are generous to share your knowledge like this, and your webpage really makes it fun to learn about bugs.
Thanks again!
Dr Gan Su-lin

Letter 5 – Crane Fly from Singapore

Unknown Freaky Mosquito Like Insect
Location: Singapore
April 4, 2011 8:15 am
Hi there,
I guess your site is my first reference when it comes to asking ”what’s this bug” again question so bear with me when I bug you guys again (pun intended). I love your site really. Anyways, I found this along with my photographer friends while trekking a narrow path of a forest. Lo and behold we found this very unusual insect on a leaf. Looks like a hybrid of a mosquito! We already cut the leaf away from the tree and laid it on a log to picture it fully, and still it never bothered to move nor fly away. Maybe you guys would know what insect is this and what species.
Thanks again.
Signature: Giovanni

Crane Fly

Hi Giovanni,
This is a Crane Fly, and it resembles a Mosquito because both Crane Flies and Mosquitoes are in the insect order Diptera, which includes all Flies.  We do not recognize the species.  We believe we found a match on FlickR that is identified as genus
Hexatoma, but we cannot substantiate that.

Letter 6 – Crane Fly oviopsits in ground

Butt thumper
Dear Bugman,
Last evening after a very good downpour, I was in our backyard in Central PA and noticed this ? thumping his or her butt on the soft ground. It would thump and fly and thump and fly and then thump and wait. I believe it is depositing eggs but am not sure. I also am not sure what it is. Any help would be appreciated. Sincerely
Larry Lochner
Hollidaysburg, PA

Hi Larry,
Your insect is a Crane Fly in the family Tipulidae, and the behavior you describe is that of a female Crane Fly laying eggs. Female Crane Flies often oviposit in the ground, and the larvae, known as Leatherbacks, feed on detritus. For more on the life cycle of a Crane Fly, visit the Crane Flies of Pennsylvania website. We are not sure of the species but we will try to contact Dr. Chen Young to see if he can assist.

Update: (06/18/2008)
Hello Daniel,
The image showed up okay this time and it looks like a female of Nephrotoma virescens to me. http://iz.carnegiemnh.org/cranefly/tipulinae.htm#Nephrotoma_virescens This species usually when freshly emerged are greenish in color and gradually turning greenish yellow as in this image. There is another species Nephrotoma alterna http://iz.carnegiemnh.org/cranefly/tipulinae.htm#Nephrotoma%20alterna which also has nice patterns on the top of the thorax. But I believe yours is a N. virescens. Thanks,
Chen

Letter 7 – Crane Fly: Pedicia albivitta

unusual insect
Hi
I have been looking for this picture for some time now and found it tonight. I live in Northwestern Ontario, Canada just outside of Kakabeka Falls. This beautiful flying insect showed up in August and I have not seen one like it since. I really enjoy your site and have it bookmarked so I can visit often. Have gone through some of your bug info lists but don’t know where to start with this one. Thanks in advance if you can identify it.
Dave

Hi Dave,
This is a Crane Fly, and we matched it to Pedicia albivitta on the Crane Flies of Pennsylvania website. We agree that it is a beautiful specimen.

Letter 8 – Crane Fly Larvae

I have recently been told I have Crane Fly Larvae. There are thousands all over Thankfully they are not eating my grass however they are all over my interlocking patio. I have three small children and aside from sweeping them up daily, what can I do to get rid of this problem? Are they harmful to my children. I know the adult crane fly does not bite but do the larvae?
With kind regards,
KJE

Dear KJE,
Crane Flies are not harmful at any stage of development. The larvae, known as Leatherbacks, eat the roots of herbaceous plants. Especially in the spring, they can get very numerous. Sorry we have no erradication advice.

Letter 9 – Crane Fly from Switzerland

Subject: Big moskito
Location: Europe (Switzerland)
June 21, 2012 6:22 am
Hi,
Just saw this bug and wondered what it is. Thanks!
Signature: No idea

Crane Fly

Dear No idea,
This is a Crane Fly, a harmless creature, and judging by the feathered antennae, this is a male specimen.  Many people mistake Crane Flies for giant mosquitoes.

Crane Fly

Thank you very much for such a precise and quick reply! Congratulations for your website.
Laurent

Letter 10 – Crane Fly with Mites from Tasmania

Subject: Strange red lumps
Location: Styx Valley, Tasmania, Australia
October 23, 2014 4:21 am
Hi there,
I would like an ID on both the insect (a crane fly?) and the strange red lumps on its thorax. Are they mites? I found this specimen on the car after a drive through a forestry logging track. Its body (excluding the legs) was probably around 2cm long.
Thanks for the help.
Signature: Curious

Crane Fly with Mites
Crane Fly with Mites

Dear Curious,
You are correct that this is a Crane Fly, and we don’t know if we are going to be able to provide you with a more specific identification beyond the Infraorder Tipulomorpha.  The red lumps do appear to be Mites, and we do have several images in our archives of Crane Flies with Mites.  We found an example from UK on The Ranger’s Blog.  We suspect the Mites are phoretic, but we are not certain.

Crane Fly with Mites
Crane Fly with Mites

Letter 11 – Crane Fly in Mount Washington

Subject:  Crane Fly
Location:  Mount Washington, Los Angeles, CA
Ides of March:  March 15, 2015
We just wrote back to Dr. Chen Young who identified a wingless Crane Fly for us, and we saw a Crane Fly on the window.  Sadly, the dorsal view is out of focus.

Crane Fly (ventral view)
Crane Fly (ventral view)

Hi Daniel,
The images are sort of out of focus and it kept me from making any further identification beyond the genus Tipula.
Thanks,
Chen

Crane Fly (dorsal view)
Crane Fly (dorsal view)

Letter 12 – Crane Fly from Honduras

Subject: Big Mosquito.
Location: Tegucigalpa, Honduras
July 23, 2017 1:40 pm
Reposted with better info.
This big bright yellow mosquito was hanging upsidedown in a rainy night. It’s body is 1.7mm long, not including the legs.
Hope you can identify it.
Signature: Quique.

Crane Fly

Dear Quique,
We believe this is a Crane Fly, not a Mosquito.  We will attempt additional research when time permits.

Thanks.
I always thought those were weird mosquitoes, hahahaha.
You learn something everyday.
Quique Olay

Letter 13 – Crane Fly from Switzerland

Subject:  Hymenoptera
Geographic location of the bug:  La Chaux-de-Fonds, Switzerland
Date: 05/06/2018
Time: 11:09 AM EDT
Your letter to the bugman:  I saw this wasp-like bug a few days ago (early may) and had never seen anything like it before. My city is at a 1000 meters of altitude and we don’t have a lot of strange bugs around here. Do you know what it is and if it’s supposed to be here in Switzerland? And also, is it dangerous?
It was about 2cm long.
How you want your letter signed:  Myriam

Crane Fly

Dear Myriam,
This is NOT a Wasp or other Hymenopteran, but it is a very effective wasp mimic.  This is actually a Crane Fly and we believe we have identified it as
Ctenophora flaveolata thanks to images posted to BioLib and Diptera Info.

Crane Fly

Thanks a lot for your quick answer! I’m relieved it’s not a dangerous bug!
Kind regards,
Myriam

Letter 14 – Crane Fly from the UK

Subject:  Flying scorpion looking thing with 6 legs
Geographic location of the bug:  London England
Date: 06/01/2018
Time: 02:57 PM EDT
Your letter to the bugman:
What is this thing? My friend has found it in his house! It looks like a flying scorpion
How you want your letter signed:  Jake

Crane Fly

Dear Jake,
Though it resembles a stinging wasp, this is actually a harmless Crane Fly.  Based on images posted to Eakring Birds and on Diptera Info, we believe your Crane Fly is
Ctenophora pectinicornis.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

5 thoughts on “Understanding What Attracts Crane Flies: Key Factors Explained”

  1. I had one of these on my wall, I went to put it out the window and it stung me?!

    At least I think it was one of these, looked very similar!

    Reply
  2. I had one of these on my wall, I went to put it out the window and it stung me?!

    At least I think it was one of these, looked very similar!

    Reply
  3. Oh this is sad as it looks like she met an untimely death. I was lucky enough to take a train trip with one of these (male) only of the “luteata” variety (I think anyway) that is found in Portugal. Such a beautiful crane fly. Fortunately mine survived the trip.

    Reply

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