Quick Answer
Hummingbirds are omnivores, meaning they eat both plant and animal materials. While the main component of a hummingbird’s diet is nectar from flowers, they also eat insects and spiders to obtain protein, vitamins, minerals, and fats. So hummingbirds have an omnivorous diet consisting of both plant and animal sources.
What Do Hummingbirds Eat?
Hummingbirds have a diverse diet that consists mainly of sugary nectar from flowers, but also includes small insects and spiders:
Nectar
– The primary food source for hummingbirds is nectar from flowers. Nectar provides hummingbirds with carbohydrates and sugars for energy.
– Hummingbirds have long slender bills that are adapted for reaching into flowers and drinking the nectar inside. Their long, forked tongues allow them to lap up nectar quickly.
– Favorite nectar sources include trumpet vine, cardinal flower, bee balm, and salvia. Hummingbirds also feed extensively on the nectar of tubular tropical flowers.
– To nourish themselves from nectar, hummingbirds must visit hundreds of flowers every day. They can consume more than their own body weight in nectar each day.
Insects and Spiders
– While nectar provides the main energy source for hummingbirds, they also consume insects and spiders to obtain essential amino acids, proteins, vitamins, minerals, and fats that are not found in nectar.
– Preferred insect prey includes small bees, ants, aphids, fruit flies, mosquitoes, gnats, and moth larvae. Spiders are also captured in midair and eaten.
– Hummingbirds may opportunistically eat the eggs and larvae of insects as another protein source.
– To meet their nutritional requirements, hummingbirds must eat hundreds of tiny insects and spiders every day to compensate for the lack of nutrients in nectar. This need for insects and spiders in their diet is what makes hummingbirds omnivores rather than straight nectarivores.
Other Food Sources
– In some tropical regions, hummingbirds will drink tree sap from holes excavated by woodpeckers as an alternative source of sugar.
– They will also feed on sugary fruits and berries when in season as another carbohydrate source to supplement nectar. Bananas and pineapple are among the favorite fruit foods.
– Hummingbirds require a lot of water and may drink rainwater collected in tree cavities, leaves, or other natural reservoirs.
– To replenish their mineral intake, hummingbirds ingest grit such as sand or tiny pebbles. This aids with digestion.
Unique Adaptations for Feeding
Hummingbirds have several specialized anatomical and physiological adaptations that allow them to thrive on their sugar-rich but nutrient-poor diet:
Nectar-Feeding Beak
– Extremely long, slender beaks adapted for probing into tubular flowers and accessing the nectar within.
– Short, edged tongues with forked tips that efficiently lap up nectar.
High Metabolism
– Very rapid metabolic rate – hummingbird hearts can beat up to 1,200 times per minute. This rapid energy burning allows them to sustain flight and power their busy foraging.
– Small body size also contributes to high metabolism, requiring more calories per ounce of body weight compared to larger birds.
Efficient Kidneys
– Able to rapidly process large amounts of nectar into energy without overloading their system with excess water or sugar.
– Their kidneys can excrete excess water efficiently so they don’t get overloaded.
Tolerance for Sugar
– Liver and muscles are able to store extra sugar from nectar as energy reserves when abundant.
– Do not suffer ill effects from high sugar diet that causes health problems in other animals.
Excellent Flight Capabilities
– Allows them to efficiently and quickly move between hundreds of flowers to meet their high energy needs.
– Maneuverable flight for catching insects and spiders midair.
How Much Nectar vs. Insects Do Hummingbirds Eat?
The proportion of nectar to insects and spiders in a hummingbird’s diet depends on the individual species, time of year, habitat, and availability of food sources:
– In most cases, nectar comprises 60-80% of total food intake. The rest consists of insects and spiders.
– During periods when nectar is less available such as winter, the proportion of insects in the diet increases.
– In tropical regions with year-round flowering, nectar may make up 90% or more of the diet seasonally.
– Smaller hummingbird species must consume a higher fraction of insects to meet their metabolic needs. Larger hummers can get by with more nectar.
– Migratory species likely consume a higher ratio of insects during migration when flowers are less abundant.
– Hummingbirds living in scrubland or forest habitats rely more on insects as a greater portion of their overall food intake compared to hummers in flower-rich meadows or gardens.
Why Do Hummingbirds Eat Insects and Spiders?
Hummingbirds supplement their nectar diet with protein-rich insects and spiders for several important reasons:
Essential Nutrients
– Nectar lacks proteins, amino acids, vitamins and minerals critical for good health – these are obtained by insect and spider prey.
– Hummingbirds have high metabolism and need more nutrients per ounce of body weight compared to other birds.
– Insects provide complete proteins with all essential amino acids not found in nectar.
Metabolic Fuel
– The fats and proteins in insects meet a hummingbird’s high energy needs. Gram for gram, insects contain more calories than carbohydrate-rich nectar.
– Eating insects provides an efficient way to pack on extra calories and fat reserves. This helps hummingbirds sustain their extreme energy expenditure.
Reproduction and Growth
– Female hummingbirds need extra protein from insects to produce eggs. Males also require more insect protein during the breeding season.
– Growing nestlings get essential nutrients for development from insects and spiders fed to them by their mothers.
Survival Food
– In cold climates or winter when fewer flowers are in bloom, insects become a vital substitute food source when nectar is scarce.
– Insects provide an important backup food to turn to if nectar supplies drop during extreme heat or droughts.
How Do Hummingbirds Catch Insects?
Hummingbirds have specialized hunting tactics for plucking insects and spiders out of the air and off surfaces:
– Preferred method is catching prey in midair. They adeptly pluck crawling and flying insects out of the air using precision aerial maneuvers.
– They glean stationary insects and spiders from leaves, branches, twigs, and bark by rapid hovering and picking.
– They snatch insects flushed from vegetation as they fly past perches.
– Traplining – efficiently flying circuits among favorite perches to snatch prey stirred up by their previous passes.
– Some species like swifts will hang out at swarms of insects to pick them off.
– Aerial sallying – chasing down prey in dramatic burst attacks from a perch. Often used for chasing large insects.
– Hover gleaning – hovering in place to scan for prey on the undersides of leaves before grabbing it. Allows access to concealed insects.
How Do Hummingbirds Digest Nectar and Insects?
Key adaptations make hummingbird digestion extremely efficient at extracting nutrients both from nectar and insects/spiders:
Nectar Digestion
– Long intestines and gut passage time allows thorough extraction of sugars from nectar.
– Rapid food transit minimizes water retention – essential when consuming large volumes of watery nectar.
– Small amounts of nectar are continuously digested with a near-constant influx of energy.
Insect Digestion
– Highly acidic stomach pH quickly breaks down insect proteins into amino acid components.
– Shorter intestinal tract for insects compared to nectar for rapid absorption of fats and proteins.
– Powerful enzymes digest tough chitin exoskeletons to access nutrients inside.
Unique Kidneys
– Ultra-efficient kidneys rapidly filter out excess water and sugars to prevent overload when consuming lots of nectar.
– Excess water from nectar is excreted as dilute urine to prevent water intoxication.
How Often Do Hummingbirds Eat?
– Hummingbirds need to eat very frequently throughout the day to power their high metabolism:
– They may visit hundreds of flowers daily lapping up nectar, eating both while hovering and perched.
– Food is processed through their digestive system in 20-30 minutes, so they eat many small meals.
– Consume roughly half their weight in nectar each day and hundreds of tiny insects.
– Eat every 10-15 minutes on average.
– Overnight fasting of up to 8 hours is normal as they enter a hibernation-like torpor state.
– Sugar water feeders may need refilling 2-3 times daily to keep up with hummingbird appetites.
– Need to feed almost continuously during peak energy expenditures like migration.
Do Hummingbirds Have a Role as Pollinators?
In addition to their role as consumers of nectar, hummingbirds serve as important pollinators for many plant species:
– Pollen sticks to their heads and bills as they feed on nectar. This pollen is transferred flower-to-flower enabling pollination and reproduction.
– Certain flower species rely on hummingbirds as their exclusive pollinator source. The flowers are adapted to hummingbird anatomy and behavior.
– Due to their small size, hummingbirds can pollinate flowers with short, narrow tubes that exclude bees and other pollinators.
– Hummingbird-pollinated plants include ornithophilous flowers with vivid red coloration and tubular shape preferred by hummers. Examples are salvia, fuchsia, and trumpet vine.
– Some species like giant hummingbirds of South America have evolved to act as specialized pollinators for equally giant flowers.
– Plants provide vital nectar nutrition for hummingbirds, and hummingbirds enable plant propagation in return through pollination. This mutualistic relationship benefits both groups.
What Happens if a Hummingbird Doesn’t Eat Enough?
Hummingbirds can rapidly decline if they do not consume enough food due to their extreme metabolism:
– May lose up to 10% of body weight overnight if not able to feed – can be deadly.
– Lethargy, weakness, and loss of ability to fly result if starved for just a few hours.
– Young hummingbirds are impacted most severely by food shortages since they have less fat reserves or energy storage.
– Abandoning nests, dropping eggs, and death of nestlings occur if female hummingbird nutrition is inadequate.
– Starvation vulnerability is highest during migration when few flower resources are available along the journey.
– Extreme cold snaps or heatwaves that kill flowers can also lead to starvation if alternative food sources are not found.
– Access to backyard feeders can make a life or death difference for hummingbirds during periods of environmental stress when flowers become unavailable.
Unique Aspects of Hummingbird Digestion
Several specializations make a hummingbird’s digestive system uniquely adapted for their nectar-based diet:
– Longer intestines and digestive tract compared to other birds for efficient absorption of sugars and micronutrients from nectar.
– Smaller guts and faster food transit when digesting higher-calorie insects to avoid excess weight.
– Powerful liver enzymes rapidly convert excess sugars from nectar into fat stores for later energy use.
– Very acidic stomach pH (around 1.8) provides ideal conditions for breaking down proteins from insect prey.
– Intestinal adaptations allow the separation of sugars from water for fast absorption of energy.
– Unique kidney structures maximize water reabsorption from nectar while excreting sugar excess.
– Antioxidant-rich pancreas protects against free radicals from oxidizing all the fats and sugars in their diet.
– Highly effective at recycling calcium, potassium, and sodium from food since nectar is low in these minerals.
Examples of Flowers Pollinated by Hummingbirds
Flower | Features Attractive to Hummingbirds |
---|---|
Trumpet Creeper | Bright red tubular flowers full of nectar |
Cardinal Flower | Clusters of vivid red blooms rich in nectar |
Bee Balm | Red flowers with high nectar volume |
Salvia | Numerous small tubular red flowers |
Fuchsia | Hanging red and purple flowers |
Firecracker Flower | Bright red blooms with protruding stamens |
Conclusion
In conclusion, hummingbirds have an omnivorous diet comprised of both plant nectar and tiny insect and spider prey. The sugary nectar provides their main energy source, while essential fats, proteins and micronutrients are obtained by consuming hundreds of small insects daily. Hummingbirds also play a vital role as exclusive pollinators for some species of plants adapted specifically to pollination by hummingbirds. Their dietary needs and foraging behaviors are shaped by unique evolutionary adaptations that allow these tiny birds to survive and thrive. Given their extreme metabolic demands, hummingbirds require frequent feeding as both predators and nectarivores. Access to both flowers and insects sources is critical to maintain their high energy lifestyles.