The Mississippi kite is a small raptor found across the southern United States. These graceful birds are a common sight in the summer months as they soar high above fields and waterways hunting for insects and small vertebrates. Mississippi kites form strong pair bonds and often return to the same nesting sites year after year. But do they reuse the same exact nest? Or do they build a new one each season? Here’s a closer look at the nesting habits of these aerial acrobats.
Mississippi Kite Natural History
The Mississippi kite (Ictinia mississippiensis) is a medium-sized bird of prey that belongs to the family Accipitridae. Adults have gray plumage on their head, back, and wings contrasted by darker gray wingtips and tail. Their undersides are pale gray and they have a black band across their eyes. Mississippi kites measure around 14 inches in length with a wingspan of approximately 3 feet.
These raptors breed in the southern United States from South Carolina to California. They migrate in the winter, traveling south to Central and South America. The total population is estimated at around 210,000 individuals.
Mississippi kites inhabit open country near water sources. They are most often found along forest edges and in areas with scattered trees and shrubs. Agricultural areas, parks, and suburban neighborhoods also provide good habitat.
These agile fliers feed primarily on insects like cicadas, grasshoppers, and dragonflies. They also prey on small vertebrates including frogs, lizards, snakes, and rodents. Mississippi kites often hunt by coursing low over open ground and snatching prey without landing.
The breeding season lasts from May to August across their range. Mississippi kites construct nests high up in tall trees, usually 20 to 60 feet above ground. Common nest trees include pines, oaks, cottonwoods, and willows. Both members of the pair help build the nest out of small sticks and twigs, lining it with leaves, moss, and lichens.
Females lay 1 to 3 eggs which hatch after about 30 days. The young fledge in around 35 days, but remain dependent on their parents for food and protection for several more weeks. Most Mississippi kites first breed when they are 2 or 3 years old.
Do They Reuse Nests?
Many species of birds use the same nest for multiple breeding attempts and across different years. Nest building requires a significant investment of time and energy, so reusing an existing structure can improve reproductive success. This is the case for a number of raptor species closely related to the Mississippi kite.
For instance, American kestrels are cavity nesters that readily reuse old woodpecker holes and nest boxes. Similarly, sharp-shinned hawks and Cooper’s hawks often refurbish old crow, squirrel, or hawk stick nests on successive years in the same territories. Bald eagles are also known to repair and reuse enormous nest structures for many seasons.
However, some raptor species like ospreys build a new nest each year. Territory fidelity is still important, but they opted not to reuse the previous season’s nest. So do Mississippi kites follow the reuse or rebuild strategy when it comes to their nest sites?
Evidence suggests Mississippi kites most often construct new nests each spring rather than refurbishing old ones. Several research studies of banded Mississippi kites found that while they returned to the same general nesting areas in consecutive years, their new nests were usually located in different trees.
One long-term study in Oklahoma found that only 2 out of 139 Mississippi kite nests over a 10-year period were reused the following year. The data showed substantial turnover in the actual nest sites within established territories from one season to the next.
There are a few possible reasons why Mississippi kites tend to build new nests annually:
- Their small, flimsy stick nests may not hold up well through the winter in exposed tree canopies.
- Nest reuse could increase parasite loads like ticks and fleas in subsequent years.
- Constructing a new nest each spring may help strengthen the pair bond.
- Abundant nesting materials reduce the need to refurbish old nests.
While reuse does occur occasionally, the bulk of evidence indicates Mississippi kites build new nests each breeding season. Their strong nest site fidelity is focused on a particular territory or cluster of potential nest trees rather than a specific previous nest structure.
Nest Site Selection
If Mississippi kites aren’t reusing old nests, how do they go about selecting new nest locations each year? Researchers have identified several key factors that influence suitable nest site selection in Mississippi kites:
Nest Height
Mississippi kites typically nest high up in mature trees. Average nest height is around 50 feet, but can range from 20 feet up to as high as 90 feet off the ground. Taller nests may help reduce predation rates and also provide good take-off access for these aerial hunters.
Tree Type
Mississippi kites show preferences for particular tree species when choosing nest sites. In one Texas study, over half of nests were found in loblolly pines and other southern pines. Bald cypress, sycamore, and black willow are also frequently used. These tree types likely offer a combination of sufficient height and branching structure to securely hold nests.
Canopy Cover
Mississippi kites often select nest trees along forest edges or in openings with lower canopy density. This allows easy flight access and helps locate prey. Completely closed canopy conditions are generally avoided.
Proximity to Water
Access to waterways, lakes, or wetlands appears important for nest site suitability. An analysis in Oklahoma showed that over 80% of Mississippi kite nests were located within 0.6 miles of a major water source.
Prior Nesting History
Mississippi kites exhibit high fidelity to previous nesting locations, even if not the exact nest structures. Quality habitat that has successfully fledged young in the past will likely be reused by the pair or new kites despite turnover of actual nest sites.
By seeking out tall trees near water and nesting close to previous sites, Mississippi kites find suitable new nest locations each year while still exhibiting traditional use of seasonal home ranges. Understanding these habitat preferences helps guide effective conservation efforts.
Typical Timeline
The nesting cycle of Mississippi kites follows a fairly consistent seasonal timeline across their range:
- Early May: Mississippi kites arrive on breeding grounds and begin courtship behaviors.
- Mid May: Pairs select nest sites and build new nests in tall trees.
- Late May: Females lay eggs, often 2-3 per clutch.
- June: Eggs hatch after 30 days of incubation.
- July: Nestlings fledge at around 35 days old.
- Mid August: Most Mississippi kites depart breeding areas for winter migration.
Nest construction may take 1-2 weeks. Both the male and female assist in gathering materials and shaping the shallow, bowl-shaped nests. If a nest fails early in the season, the pair may build a second one and re-nest.
Once the young fledge in July, Mississippi kites become more social. Loose flocks will congregate and hunt together prior to fall migration. The peak timing of nesting and migration can vary somewhat across different regions.
Population Trends
After declining during much of the 20th century, Mississippi kite numbers have rebounded in recent decades. Protection under the Migratory Bird Treaty Act along with nest monitoring programs have aided this recovery. Their current global population is considered stable and they are ranked as a species of Least Concern on the IUCN Red List.
However, localized threats from habitat loss, nest disturbance, and climate change remain concerns for the future of Mississippi kites. Continued protection and management focused on nesting sites will help maintain healthy populations of these aerial acrobats into the future.
Key Facts
- Mississippi kites form long-term pair bonds and exhibit high mate fidelity from year to year.
- They show strong nest site fidelity but usually build a new nest each breeding season.
- Average nest reuse rates are low, around 1-2%, based on available data.
- New nests are often located close to previous years’ sites within established territories.
- Preferred nest trees are tall pines, cypress, oak, or willows along forest edges.
- Nest height averages around 50 feet high but can range from 20 to 90+ feet up.
- Proximity to water and previous nesting success influence nest site suitability.
- Understanding nest requirements helps guide effective habitat management for this species.
Conclusion
Research into Mississippi kite nesting biology reveals some interesting insights. While mate fidelity and nesting territory loyalty are very strong in this species, they do not often reuse old nests. The bulk of evidence shows Mississippi kites construct new stick nests each spring, presumably to reduce parasites and freshen bonding behaviors.
Nest site selection is driven by key habitat cues like tall trees near water and prior nesting success. This allows the kites to return to productive areas while often shifting the actual nest location from year to year.
By studying nest reuse patterns and nesting requirements, scientists can better understand the breeding ecology of Mississippi kites. This information also assists conservation efforts and recommendations aimed at protecting essential habitat for these aerial insectivores into the future.
