Hummingbirds are amazing little creatures known for their ability to hover in midair and fly backwards. Their rapidly flapping wings allow them to perform aerial acrobatics that seem to defy physics. But with climate change leading to more frequent and intense heat waves across North America, an important question arises – can hummingbirds survive extreme heat?
What temperatures can hummingbirds tolerate?
Hummingbirds have an impressive ability to withstand a wide range of temperatures due to their high metabolisms and ability to enter torpor. During torpor, hummingbirds lower their body temperature and heart rate dramatically to conserve energy. This allows them to survive overnight temperatures as low as zero degrees Fahrenheit. On the upper end, they have been known to tolerate temperatures over 100 degrees Fahrenheit while feeding. However, prolonged exposure to extreme heat over 105 degrees can be dangerous and even fatal.
How do hummingbirds stay cool?
Hummingbirds have several behavioral adaptations to help them keep cool in hot conditions:
– Panting – Like dogs, hummingbirds pant to promote evaporative cooling. As they breathe rapidly, evaporation from their moist mouth and throat areas helps lower their body temperature.
– Wing fluttering – Hummingbirds will flutter their wings even while perched to move air over their bodies when overheated.
– Seeking shade – Hummingbirds will seek out cooler microclimates during the heat of the day, resting in the shade of trees and shrubs.
– Bathing – Hummingbirds will bathe in water sources like bird baths, sprinklers, and waterfalls to cool their skin. The evaporation of water from their feathers promotes cooling.
Do hummingbirds need to drink more in high heat?
Yes, like all animals, hummingbirds have increased water needs in high heat. They are especially vulnerable to dehydration due to their extremely high metabolisms. Hummingbirds must consume more than their own body weight in nectar each day just to meet their energy needs. This also means they take in a lot of water from nectar. However, in extreme heat when water needs are higher, they may not get enough from nectar alone. Providing a bird bath or dripper for drinking water can be a life-saver for hummingbirds in hot weather. Misting vegetation around feeders also helps provide supplemental moisture.
How Extreme Heat Impacts Hummingbirds
Prolonged exposure to high temperatures over 105 degrees Fahrenheit can cause a number of problems for hummingbirds:
Hyperthermia
Hyperthermia occurs when a hummingbird’s body temperature becomes dangerously elevated above its normal 105°F range. As their body overheats, hummingbirds will become lethargic and have trouble maintaining their rapid wing-flapping. If their temperature continues to rise, it can lead to organ damage, muscle failure, and even death.
Heat exhaustion
Heat exhaustion sets in when a hummingbird becomes dehydrated and cannot pant fast enough to dissipate building heat. Symptoms include weakness, labored breathing, and rapid pulses. Heat exhaustion can lead to heat stroke if left untreated. Providing drinking water is critical.
Heat stress
Extreme heat, even when not severe enough to cause hyperthermia or heat exhaustion, places significant stress on hummingbirds. It forces their metabolism into overdrive which rapidly depletes fat stores and can affect reproduction, migration, and susceptibility to illness. Access to adequate nutrition and water sources are important for mitigating heat stress.
Dietary effects
Hot weather causes nectar sources to dry up faster. Lack of access to adequate nutrition weakens hummingbirds’ ability to withstand heat. Providing supplemental nectar through feeders is important during heat waves when natural flowers may be in short supply.
How Climate Change Affects Hummingbirds
Climate change poses some significant threats to hummingbirds in addition to increasing exposure to extreme heat:
Shifting bloom cycles
Flowers are blooming earlier as climate change disrupts natural cycles. This can create a mismatch between bloom periods and periods when hummingbirds migrate and nest. Hummingbirds depend on a consistent nectar supply. Altered bloom cycles due to climate change may jeopardize this.
Threats to migration
Climate change is shifting precipitation patterns and lengthening summers which may impact hummingbird migration and ability to breed multiple times. Hotter temperatures cause flowers to dry up sooner so hummingbirds must migrate earlier and breed faster to ensure enough food supplies. Longer summers with prolonged heat could exhaust birds.
Drought conditions
Increased frequency of drought in some regions due to climate change can cause shortages in nectar and breeding habitats for hummingbirds. Lack of water also makes it harder for them to keep cool. Providing supplemental water is important during droughts.
Sea level rise
Rising sea levels threaten many prime hummingbird habitats like meadows and scrublands. Nesting sites and food sources could be lost. Hummingbirds may be forced farther inland.
Habitat disruption
Climate-related threats like flooding, wildfires, insect infestations, new predators, and diseases may alter hummingbird environments and ecosystems. Hummingbirds may struggle to adapt to rapidly changing habitats.
Steps to Help Hummingbirds in Hot Weather
Here are some tips for supporting hummingbirds during periods of extreme heat:
Provide clean, fresh water
Ensure hummingbirds have a clean water source for bathing and drinking such as a bird bath, fountain, sprinkler, or seeping hose. Change water daily to prevent mosquitoes. Add stones for perching near water.
Offer supplemental food
Keep feeders cleaned and stocked with fresh nectar (1 part sugar to 4 parts water). Provide extra feeders in both sun and shade areas. Also supplement with fruit wedges.
Mist vegetation
Mist vegetation around your yard early in the day to provide humidity without soaking feathers. Hummingbirds may sip water drops from leaves.
Give them shade
Ensure your yard has plenty of shaded areas for hummingbirds to rest and cool down. Plant shade trees and shrubs if needed.
Insulate feeders
Use feeders with built-in insulation or add insulation with styrofoam to help keep nectar cool and prevent fermentation.
Use drippers
Attach a slow-flow dripper to feeders to automatically provide a small fresh water supply.
Avoid pesticides
Pesticides can be toxic to hummingbirds, especially when they are heat stressed. Use natural alternatives if pest control is needed.
Monitor their health
Watch for signs of heat distress like lethargy, weakness, and labored breathing. Call a wildlife rehabilitator if you see injured or unwell birds.
Provide habitat necessities
Ensure your yard also offers shelter, nesting sites, and native plants that attract insects which hummingbirds eat. Hummingbirds need a well-rounded habitat to thrive.
Future Outlook for Hummingbirds
The future survival of hummingbirds in a warming world depends on a few key factors:
Habitat conservation
Preserving intact habitats and ecosystems will be vital so hummingbirds have access to the diverse nectar sources, nesting sites, and insect populations they require. This means protecting parks, refuges, meadows and other natural areas.
Expanded migration corridors
Maintaining connectivity between breeding and wintering grounds will enable hummingbirds to shift ranges as climate changes. Corridors of intact habitat need to link protected areas so hummingbirds have migration routes.
Reduced carbon emissions
The long-term outlook for hummingbirds will ultimately depend on slowing the pace of climate change by reducing greenhouse gas emissions and curbing global temperature rise. Even if we help hummingbirds adapt now, an unchecked rise in global heat will threaten their survival.
Backyard habitats
While large-scale conservation initiatives are crucial, small-scale efforts in backyards are also important. Providing habitat needs, food sources, and supplemental water and shade in home gardens can go a long way in supporting local hummingbird populations.
Citizen science
Tracking hummingbird populations, behaviors, health, and migrations through citizen science programs will provide valuable long-term data to guide conservation policies. Project FeederWatch is one great option to get involved.
| Type of Impact | Specific Threats |
|---|---|
| Physiological stress |
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| Behavioral changes |
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| Reproductive issues |
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| Habitat degradation |
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Conclusion
Hummingbirds are remarkable creatures that add beauty, wonder, and important ecosystem services like pollination to our world. While they have some impressive adaptations for tolerating heat, extreme high temperatures do pose a real threat to hummingbird health, reproduction, and survival. Climate change is exacerbating heat risks by altering habitats, disrupting seasonal rhythms, and increasing the frequency of heatwaves. Through conservation initiatives, reducing emissions, and creating backyard habitats, we can give hummingbirds a better chance of thriving despite higher heat. But the future of hummingbirds in a rapidly changing climate remains uncertain. Their fate will ultimately depend on our ability to address the underlying cause of rising temperatures – human-caused climate change.
