Bird mites are tiny arachnids that live as external parasites on birds. They belong to the taxonomic order Astigmata or Acari. There are over 20 different species of bird mites that can infest birds and bite humans, the most common being:
- Northern fowl mite (Ornithonyssus sylviarum)
- Tropical fowl mite (Ornithonyssus bursa)
- Scaly leg mite (Knemidocoptes mutans)
- Depluming mite (Neodectes gallinae)
- Itch mite (Dermanyssus gallinae)
- Red mite (Dermanyssus gallinae)
Bird mites normally live their entire 3-4 week life cycle on their bird hosts. However, when the host birds abandon their nests or die, the mites can lose their food source and migrate in search of a new host. This is when they can enter human environments and bite humans, causing itchy red welts.
The key question is, how long can bird mites survive without having a bird host to feed on? Read on for a detailed look at the bird mite life cycle and ability to survive without a host.
Bird Mite Life Cycle
Bird mites go through 4 life stages:
- Egg – Females lay 2-5 eggs per day. Eggs hatch in 2-3 days.
- Larva – Legless larvae emerge and molt into a nymph stage in 3-5 days.
- Nymph – Nymphs have 8 legs and molt into adults in 5-8 days.
- Adult – Adults mate and females lay eggs to continue the cycle. Adults can live for 3-4 weeks.
The entire life cycle takes around 7-22 days depending on species and conditions.
Bird mites spend their entire life on the host bird where they feed on blood, skin and secretions. The mites remain on the bird except to transfer between host birds or seek new hosts.
Do Bird Mites Die Without a Host?
Bird mites are unable to survive for long periods without having a host to provide a blood meal. Their mouths are adapted for piercing skin and sucking blood. Without blood meals, the mites will die. However, some species are able to survive longer than others while searching for a host.
Here is how long different bird mites can survive without a host:
Northern Fowl Mites
– Eggs – Can survive for up to 10 days without hatching if the temperature is below 60°F. Warmer temperatures shorten survival time.
– Larvae – Maximum of 4-12 days after hatching. Require a blood meal soon after hatching.
– Nymphs – Up to 5 days after molting from larval stage.
– Adults – Adults may survive up to 7 days without feeding in cooler temperatures. Warmer temperatures reduce survival time.
Overall, **northern fowl mites live a maximum of 2 weeks without a host**. Low temperatures allow slightly longer survival times. Newly hatched larvae need to feed within a few days. Adults can go approximately 1 week unfed.
Tropical Fowl Mites
Tropical fowl mites tend to survive a little longer than northern species when hosts are not present. Approximate survival times are:
– Eggs – Up to 3 weeks if temperature is below 60°F.
– Larvae – Up to 1 week after hatching.
– Nymphs – Up to 10 days after molting.
– Adults – Survive 2-3 weeks without feeding.
**Tropical fowl mites can live for 3-4 weeks without a host**. The warm climate they have adapted to allows longer survival times when hosts are unavailable.
Scaly Leg Mites
Scaly leg mites spend their entire life cycle burrowed into the skin on birds’ legs and feet. They have a different feeding pattern than other bird mites.
– All Life Stages – Can persist for up to 3 weeks embedded in skin flakes and debris after a host dies. Mites must find a new host shortly after to survive.
**Scaly leg mites may persist for up to 3 weeks without a host** if embedded in skin material. Their burrowing habit helps them survive a bit longer.
What Factors Affect Bird Mite Survival Without a Host?
Several environmental factors affect how long bird mites can survive when detached from their hosts:
Temperature
– Warm temperatures above 85°F decrease survival times. Mites dehydrate faster in heat.
– Cool temperatures below 60°F extend survival up to 2 times longer.
Humidity
– Low humidity shortens survival by causing dehydration.
– High humidity can double survival time by preventing water loss.
Location
– Being deep in nesting areas or feathers extends survival a bit.
– Being out in the open exposed to elements will shorten survival.
Here is a table summarizing how different conditions affect mite survival without hosts:
Condition | Shorter Survival Time | Longer Survival Time |
---|---|---|
Temperature | Above 85°F | Below 60°F |
Humidity | Low humidity | High humidity |
Location | Exposed | Burrowed in nests |
As this table illustrates, cooler temperatures, higher humidity, and being buried deep in nesting areas allows bird mites to survive longer when detached from hosts. However, even in ideal conditions, most mites cannot persist longer than 1-2 months without a blood meal.
Survival Adaptations
Bird mites have anatomical and behavioral adaptations that help them survive for short periods without hosts:
– Small size – Their tiny size allows them to burrow deep into feathers and skin for protection.
– Lower metabolism – A lower metabolism requires less frequent feeding.
– Hardy exoskeleton – A tough external shell prevents water loss.
– Aggregate in groups – Clumping together helps retain moisture.
– Migrate on wind currents – Some species use air currents to migrate and find new hosts.
Despite these adaptations, bird mites cannot fully shut down their metabolism or go into true hibernation. They require regular blood meals from hosts to replenish energy and moisture. Most species will die within several weeks without a host.
Finding New Hosts
When original bird hosts die or leave nesting areas, some bird mites migrate by crawling onto vegetation and waiting for new hosts. Others attach to flying insects to hitch rides to new locations. Some species can migrate on wind currents.
Bird mites detect cues like temperature, carbon dioxide, and vibrations to identify new hosts. When they reach human structures, they mistakenly identify humans as possible new hosts and bite. Their bites usually do not transmit disease but can cause itchy welts.
This host seeking behavior is why bird mites only temporarily infest human living spaces when original hosts disappear. Once they fail to find a suitable new host, the mites eventually die off.
Treating Mite Infestations
Since bird mites die within several weeks without hosts, the main treatment step is removing the original bird hosts. This can involve:
– Removing abandoned nests around the home.
– Installing bird deterrents like spikes, gels, and nets.
– Fixing openings in roofs and walls that allow bird entry.
– Avoiding contact with wild bird nests.
Once birds are evicted, regular cleaning and vacuuming will remove and kill any lingering mites. Insecticide sprays containing pyrethroids can help kill mites on surfaces and prevent bites. Monitor areas for 1-2 months since some mites may survive this long without hosts.
Conclusion
Bird mites normally spend their entire short life cycle on their hosts. When hosts die or leave, the mites can only survive for a limited time while seeking new hosts. Exactly how long bird mites survive without hosts depends on the species and environmental conditions:
– Northern fowl mites live for a maximum of 2 weeks without a host.
– Tropical fowl mites survive for 3-4 weeks unfed.
– Scaly leg mites embedded in skin may persist for 3 weeks without a host.
Cool temperatures, high humidity, and staying buried in nesting areas allows mites to survive for the longest time. However, most mites die within several weeks without a blood meal.
Treating homes involves removing original bird hosts. With the hosts gone, any lingering mites soon die off. Monitoring for 1-2 months ensures no mites persist. Understanding the short survival abilities of bird mites helps create an effective treatment strategy.