The practice of hanging a hummingbird feeder is a popular way to observe these tiny, energetic birds, but it raises a common question: should the feeder be left outside overnight or brought in? Managing a feeder after sunset involves considering the hummingbirds’ biology, the risk of attracting unwanted nighttime visitors, and the hygiene of the sugar solution. Bringing the feeder indoors after dusk is generally the best practice for maintenance and safety.
Hummingbird Feeding Schedules
Hummingbirds are strictly diurnal, meaning their feeding activity is restricted to daylight hours. They possess the highest mass-specific metabolic rate of any warm-blooded animal, requiring them to constantly consume nectar and small insects throughout the day. Due to this high energy demand, they cannot afford to waste energy searching for food in the dark.
As the sun sets, hummingbirds conserve energy by entering a deep, sleep-like state called torpor, which is similar to a short-term, daily hibernation. During torpor, a hummingbird’s metabolic rate can drop by as much as 95%, and its heart rate and body temperature are significantly lowered. This state allows them to survive the night without needing to feed, making the feeder unnecessary until they rouse at dawn.
Addressing Nocturnal Pests
Leaving the sugar solution out at night attracts a variety of nocturnal creatures that can cause damage or create safety hazards. Larger nocturnal mammals, such as raccoons, opossums, and bears in some regions, are strongly drawn to the nectar’s high sugar content. These animals can knock down the feeder, causing breakage, or drain the entire contents, leaving nothing for the hummingbirds in the morning.
Common nocturnal insect pests include ants, wasps, and some species of nectar-feeding bats, particularly in the southwestern United States. Ants can clog the feeding ports and contaminate the nectar by drowning in the solution. Bringing the feeder in eliminates the risk of attracting larger, potentially destructive animals that could become a nuisance or danger to homeowners.
Maintaining Nectar Freshness
The sugar solution is a perfect environment for the rapid growth of microorganisms. Leaving the feeder exposed to fluctuating nighttime temperatures, especially in warm climates, accelerates spoilage. When temperatures are consistently above 70°F, bacteria and mold growth increase, potentially causing the nectar to ferment in as little as one to two days.
Nectar contaminated with mold and bacteria can be harmful to hummingbirds, potentially causing infections. Warm conditions encourage the proliferation of these microorganisms. Regularly removing the feeder overnight, particularly during hot weather, helps slow deterioration, ensuring the birds have access to a clean and safe food source when they wake up.
Preparing the Feeder for Morning
Bringing the feeder in is a simple process that provides an opportunity to inspect the unit for damage or contamination. Once the last hummingbird has visited, the feeder can be taken down and placed in a cool location. Storing the feeder in a refrigerator overnight is an effective way to slow microbial growth and maintain nectar freshness.
The most important step is ensuring the feeder is back in place before the hummingbirds begin their day. Hummingbirds are among the earliest risers, beginning their search for food approximately 30 to 45 minutes before sunrise to refuel after torpor. Re-hanging the feeder at the first hint of dawn guarantees their crucial first meal is available precisely when they need it.