Birds have a variety of strategies and adaptations to deal with heavy rain. Their behaviors and ability to cope with extreme weather depends on the species, habitat, and severity of the storm.
Take Cover
Many birds will seek shelter during heavy rain. They may hide out under dense foliage, inside cavities of trees or nest boxes, under rocks or overhangs, or even inside man-made structures like barns or porches. Staying dry helps maintain their body temperature and reduces their risk of exposure.
Fluff Up Feathers
Birds will fluff up their feathers to trap air against their bodies for insulation. This helps them retain body heat. The layer of air acts as a barrier against the cold rain. They may also turn their backs to the wind or rain to minimize direct exposure.
Perch and Wait
Some birds may simply perch on a branch and wait out a storm. Their feathers are designed to be waterproof, repelling water so the birds don’t get soaked to the skin. Preening helps maintain feather condition. However, heavy rains can still chill birds or even lead to hypothermia if exposure is too long.
Keep Foraging
Species adapted to wet environments may continue foraging during rain. This includes waterfowl, seabirds, and wading birds that are accustomed to getting their feathers wet. They have dense plumage oiled by preen glands that “beads” water. Ducks even have comb-like structures on their beaks to filter out food from the water.
Migrate Early
Some birds may start their seasonal migrations early to escape harsh rainy periods. Roseate Spoonbills in the Florida Everglades have been observed migrating north weeks earlier than normal prior to heavy summer rains. This allows them to breed in drier habitats.
Alter Routes
Birds may alter migration routes to avoid rainfall over oceans and other barriers. Radar studies of migrating birds over the Gulf of Mexico show mass changes in direction to avoid storm systems. Some species wait for favorable winds behind cold fronts before making long overwater crossings.
Maintain High Energy Levels
Birds require extra energy to keep warm and survive storms. This means they need to increase their food intake prior to and during rains. You may see increased foraging behavior and aggression as birds compete for limited food sources. They consume enough calories to sustain higher metabolic rates.
Huddle Together
Some colonial nesting birds will huddle together during rain storms to conserve body heat. Penguins form dense groups, tucking flippers into their bodies. Pelicans squeeze together bill-to-bill with young nestled safely underneath them. Turkeys and grouse may also form coveys.
Take Frequent Baths
Bathing helps birds maintain healthy feathers. The waterproofing comes from oils distributed during preening. Birds may take more frequent baths during rainy periods to improve water resistance and insulating abilities. However, heavy preening uses up extra energy.
Seek Alternative Food Sources
Normal insect prey may be harder for insect-eating species to find in heavy rains. As a result, some birds expand their diets during storms. Warblers and chickadees may visit feeders more often. Gulls can adapt to grab fish and earthworms washed up by flooding.
Behavior Changes by Species
Species | Rainy Behavior |
---|---|
Hummingbirds | Seek shelter in dense trees and bushes |
Woodpeckers | Stay inside cavities; drum on trees under cover of canopy |
Finches | Fluff up feathers while perched; consume more food prior |
Hawks | Reduce flying; pluck wet prey items quickly |
Herons | Hunch over with neck retracted; roost communally |
Gulls | Scavenge on flooded ground; bathe frequently |
Terns | Dive for fish pushed closer to surface |
Crows | Use intelligence to utilize tools and solve problems |
Nesting and Reproductive Effects
Rain can impact nesting birds in several ways:
- Heavy rainfall may flood out ground nests.
- Storms can blow chicks and eggs out of elevated nests.
- Increased humidity reduces embryo survival.
- Adults may have to remain on nests more to protect young.
- Fewer insects reduce food supplies for developing chicks.
Birds may adapt by building domed nests on the ground or delaying breeding until storms have passed. Extreme rains during migration can also throw off arrival times and reproductive timing.
Advantages of Rain
While heavy rain can certainly create challenges, it also offers some benefits that birds may exploit:
- Wet leaves make caterpillars and worms more visible.
- Flooding concentrates prey like fish and frogs.
- Insects emerge after rainfall, providing food bonanzas.
- Damp soil makes digging for seeds and invertebrates easier.
- Rain pools provide bathing and drinking opportunities.
Conclusion
Birds have remarkable abilities to detect and respond to impending rainfall through changes in barometric pressure, wind, and humidity. Their behaviors before, during, and after storms demonstrate the impressive flexibility of birds to adjust to ever-changing environments. While heavy rain can certainly impose costs, most birds are well-equipped to cope.