The Great Kiskadee (Pitangus sulphuratus) is a passerine bird in the tyrant flycatcher family Tyrannidae. They are large, noisy birds that are mostly found in South and Central America. Great Kiskadees have a varied diet that includes insects, small vertebrates and fruit. Their opportunistic feeding habits allow them to thrive in a range of habitats from open savannah to urban areas. In this article, we will take a detailed look at the diet of the Great Kiskadee.
Insects
Insects make up a large part of the Great Kiskadee’s diet. They often catch insects while making short flights from an observation perch. Great Kiskadees are able to spot and pursue fast moving insects in flight. Some of the common insects that Great Kiskadees prey on include:
- Beetles
- Crickets
- Grasshoppers
- Cicadas
- Moths
- Butterflies
- Flies
- Bees
- Wasps
- Ants
Great Kiskadees use a variety of hunting techniques to catch different types of insects. They may perform aerial hawking maneuvers to catch flying insects. For crawling insects on the ground, they use an opportunistic perch-to-ground attack method. Kiskadees often impale larger insects on thorns or barbed wire before eating them. This helps immobilize the prey and break it into smaller, more manageable pieces.
Some researchers have analyzed the stomach contents of Great Kiskadees to determine the composition of insects in their diet. One study in Brazil found that Hymenoptera (wasps, bees, ants) made up over 70% of the insect volume, followed by Orthoptera (grasshoppers, crickets), Hemiptera (true bugs), Coleoptera (beetles) and Lepidoptera larvae (caterpillars). Regional and seasonal availability influences the types of insects Kiskadees consume.
Small Vertebrates
Great Kiskadees are opportunistic foragers and will prey on small vertebrates in addition to insects. Lizards make up a large proportion of their vertebrate prey. They use the same perch-attack hunting technique to capture lizards on the ground. Some small snakes and frogs are also occasionally eaten.
Nestlings and eggs are vulnerable to kiskadee predation. Great Kiskadees may raid nests of small birds to eat eggs and chicks. This includes domed nests of ovenbirds and warblers which kiskadees are able to access with their stout beaks. Rodents, such as mice and bats, may also sometimes get grabbed by hunting kiskadees.
Fruit
Fruit is a favorite food source of Great Kiskadees. They consume a wide variety of small berries and fruits. Plant species frequently eaten include:
- Brazilian peppertree
- Loquat
- Guava
- Banana
- Mango
- Fig
- Passionfruit
Kiskadees play an important role in dispersing the seeds of these plants after the fruits are eaten. Their strong beaks allow them to access the pulp of hard fruits. They can pick fruits while hovering and eat them in mid-air which reduces competition for fruit resources.
Fruits provide an abundant source of carbohydrates and vitamins. Kiskadees seem to preferentially choose ripe, sugar-rich fruits. The proportion of fruit in the diet varies seasonally and based on local availability. During times of ripening fruits, kiskadees may get over 50% of their daily food intake from fruits.
Other Foods
Great Kiskadees have been documented eating a wide range of other food items. Here are some additional components of their broad, opportunistic diet:
- Mollusks like snails and mussels
- Earthworms
- Spiders
- Scorpions
- Millipedes
- Small fish
- Tree sap
- Nectar
- Human food scraps
They are able to utilize this variety of food sources due to their versatile feeding techniques and behaviors. Kiskadees modify their hunting strategy based on the type of prey. They probe leaf litter and bark crevices for concealed invertebrates. Larger hard-shelled prey is subdued by beating it against a perch.
Feeding Behaviors
Great Kiskadees exhibit a variety of clever feeding behaviors and adaptations:
- Flycatching – chasing insects while in flight
- Hang-gleaning – hanging upside-down to pick insects and fruits
- Hover-gleaning – plucking food while hovering next to it
- Perch-attacking – swooping down on prey from an observation perch
- Hawking – catching flying insects in mid-air
- Impaling – to immobilize large prey on thorns
- Food-stealing – occasionally stealing prey from other birds
Their big heads, large gapes, and stout pointed beaks allow them to handle a range of food types. Strong jaws empower them to crush hard-shelled insects and break open fruits. They have excellent eyesight to detect prey movements from a distance. Kiskadees are smart, agile, and acrobatic hunters.
These birds hunt both from stationary perches and on the wing. A single observation post is used to scan for prey over an extended period before moving to another. Kiskadees often reuse favorite perches. They aggressively defend these productive hunting perches against other birds.
Great Kiskadees are most active in the early morning and late afternoon. They feed in open habitats at forest edges and gaps with good visibility. The male and female may sometimes cooperate in attacking larger prey animals. Food is often brought back to nestlings during breeding season.
Habitat and Range
The wide habitat range of Great Kiskadees allows them access to diverse food sources:
- Open woodlands
- Savanna
- Riparian corridors
- Suburbs and parks
- Agricultural areas
- Partially cleared forests
Great Kiskadees are found across South America east of the Andes mountains. Their range extends from southern Mexico to central Argentina and Uruguay. Regions include:
- Brazil
- Bolivia
- Paraguay
- Argentina
- Colombia
- Venezuela
- Ecuador
- Peru
They reside in a variety of habitats across this broad latitude. Kiskadees were first reported in the United States in Texas in the 1940s where a small breeding population still exists. Their adaptability has allowed them to thrive from the tropics to subtropics.
Diet Composition
Researchers have analyzed the stomach contents of Great Kiskadees to understand their generalized diet composition:
Food Type | Percent Volume |
---|---|
Insects | 49% |
Fruits | 48% |
Vertebrates | 3% |
This shows nearly equal proportions of insects and fruit in their diet. Insects provide protein, while fruits offer carbohydrates and nutrients. Vertebrates provide supplemental protein.
The diet composition changes seasonally based on food availability. During winter, up to 78% of the diet may be insects. In summer, a majority of the diet can be fruit when ripe berries and drupes are abundant. Their generalized diet allows them to switch food sources opportunistically.
Hunting Adaptations
Great Kiskadees have many physical and behavioral adaptations that allow them to exploit such a wide range of food sources:
- Strong visual perception – detect prey movement up to 100m away
- Wide gape – to swallow large prey
- Pointed bill – grasp and tear food items
- Robust jaws – crush hard shells and bones
- Quick, agile flight
- Intelligent hunting techniques
- Perch-attack strategy
- Impaling prey
These adaptations provide kiskadees with great flexibility in the types of food they can utilize. Their sturdy bills give them access to prey with hard exoskeletons. Speed and maneuverability allows them to catch evasive insects and vertebrates. Intelligence and learning enables them to employ optimal strategies against different prey types.
Breeding and Nestlings
Great Kiskadees begin breeding in spring. They build cup-shaped nests in the fork of a tree. The female lays 2-4 eggs which are incubated for 17-18 days. Both parents share brooding and feeding duties.
Nestlings remain in the nest for about 3 weeks as they are fed and grow their flight feathers. Kiskadee nestlings open their mouths wide and vocalize intensely when parents arrive with food. The adult birds regurgitate partially digested insects directly into the mouth of begging chicks.
As chicks get older, parents start bringing pieces of fruits and vertebrates. Chicks need protein-rich insects for growth early on. Towards fledging, they are fed increasing amounts of fruit to build fat reserves. The chicks watch parents to learn hunting skills and are fed until 3-4 weeks after leaving the nest.
Food Availability by Season
Great Kiskadees take advantage of fluctuating seasonal food sources:
Season | Peak Food Sources |
---|---|
Spring | Insects, lizards, berries |
Summer | Insects, fruits |
Fall | Insects, berries, lizards, fruit |
Winter | Insects, some fruit |
Their diverse palate allows Great Kiskadees to shift food sources as availability changes seasonally. Insects and lizards provide abundant protein in spring for breeding. Fruits offer peak nutrition in summer/fall as they ripen. Scarce fruit is supplemented with more insects in winter.
Interactions with Humans
The opportunistic nature of Great Kiskadees brings them into close contact with humans. They exploit human-modified habitats and food waste:
- Scavenge scraps in markets and restaurants
- Consume fruit in orchards and gardens
- Hunt insects attracted to lights at night
- Use utility poles and wires as hunting perches
Kiskadees are adapted to take advantage of the resources provided by human habitats. They skillfully avoid traffic while hunting along roads. Their loud, scolding call often draws attention. These birds peacefully coexist with humans across their range.
Some people enjoy seeing Kiskadees visit their gardens for fruit and insects. However, their nests can occasionally be a nuisance if built in an inconvenient spot. Overall, Great Kiskadees are charismatic birds that thrive alongside human settlements.
Conclusion
Great Kiskadees have a remarkably varied diet that includes insects, small vertebrates, fruits, and human scraps. They employ an array of hunting techniques and adaptations to exploit diverse food sources. Their ability to shift between different foods depending on seasonal availability enables them to flourish across a wide habitat range from Mexico to Argentina. While the proportion of insects, fruits and vertebrates fluctuates, their overall diet composition remains opportunistic and generalized. Great Kiskadees serve as an excellent example of behavioral and dietary flexibility in birds. Their adaptability will continue to allow them to thrive alongside human activity into the future.