How common are glossy ibis in Florida?

The glossy ibis (Plegadis falcinellus) is a wading bird species that can be found throughout Florida. Glossy ibis are medium-sized birds with long, curved bills that they use to probe for food in shallow wetlands. Their plumage is dark brown overall, with metallic green, purple, and bronze iridescence on the wings and body.

Glossy ibis are considered common to locally abundant in Florida, especially in the southern and coastal regions of the state. However, their populations can fluctuate from year to year depending on water levels and habitat conditions. In this article, we will look at population estimates, range, habitat preferences, and conservation status of the glossy ibis in Florida.

Population Estimates

Getting precise population estimates for glossy ibis in Florida can be challenging, as the birds move around frequently in response to changing water levels and food resources. However, some general estimates exist based on bird surveys and counts:

• Partners in Flight estimates the Florida breeding population at 5,000-10,000 pairs.
• The North American Breeding Bird Survey estimated 16,400 individual glossy ibis in Florida for the period 1966-2015.
• Audubon’s climate model predicts the Florida population could decline to approximately 12,200 individuals by 2080 due to loss of coastal wetland habitat.
• Counts of wintering and migrating flocks number in the hundreds or low thousands of birds.

So in general, current total population estimates range from tens of thousands up to around 100,000 individuals in Florida. The glossy ibis is considered a common bird, but populations are below levels that would make it abundant statewide. Conservation efforts for wetlands will be important for maintaining healthy numbers.

Range and Habitat in Florida

Glossy ibis occur statewide throughout Florida, but are most abundant in coastal regions and southern areas of the state. Their preferred habitats are shallow freshwater and saltwater wetlands, including:

• Freshwater marshes
• Swamps
• Flooded pastures or agricultural fields
• Mangrove forests
• Estuaries
• Saltwater and brackish marshes
• Mudflats

They also forage in shallow-water edges of lakes, ponds, canals, and ditches. Abundant wetlands and proximity to nesting, feeding, and roosting sites are key to supporting glossy ibis populations.

Breeding Range

Glossy ibis breed in Florida from March to June, with nesting concentrated in the Everglades ecosystem but occurring statewide. They build platform nests in trees or shrubs above water. After breeding, flocks disperse along coasts and inland wetlands.

Wintering Range

In winter, ibis congregate in large flocks at favored feeding areas across the southern half of Florida. Wintering populations are augmented by migrants arriving from further north. Prime wintering areas include Stormwater Treatment Areas near the Everglades, Merritt Island National Wildlife Refuge, Tampa Bay, Florida Bay, and J.N. “Ding” Darling National Wildlife Refuge.

Conservation Status

The glossy ibis is classified as a species of Least Concern on the IUCN Red List. Its global population is estimated at 1 million to 3 million adults and appears stable. In Florida, the species has a conservation ranking of S5, meaning it is demonstrably widespread and secure in the state.

However, habitat loss remains a concern. Development, agriculture, and water management all threaten the wetlands glossy ibis rely on. Conservation efforts for Florida wetlands will benefit glossy ibis by preserving essential feeding and nesting sites. The Florida Fish and Wildlife Conservation Commission classifies the glossy ibis as a Species of Special Concern, meaning it requires monitoring and habitat management to maintain healthy populations.

Interesting Facts

Here are a few interesting facts about the glossy ibis in Florida:

• They are social foragers that feed together in flocks of up to hundreds of birds.
• Their curved bill allows them to probe for fiddler crabs, crayfish, insects, fish, frogs, and other prey in muddy wetlands.
• Glossy ibis produce a distinctive “growling” or “grunting” call.
• They build platform stick nests in shrubs and trees over water.
• Both parents share incubation duties and feed the chicks after hatching.
• Young ibis develop quickly, leaving the nest after 25 days but continuing to be fed by parents for several more weeks as they learn to forage.
• The species declined in Florida early in the 20th century due to plume hunting but recovered after protection.

Conclusion

In summary, the glossy ibis is considered a common but not abundant wetland bird in Florida. Tens of thousands breed in the state, while wintering populations may reach up to 100,000 birds. They occur statewide but prefer shallow wetland habitats such as marshes, swamps, and estuaries. Conservation of Florida’s essential wetland ecosystems will benefit glossy ibis by providing habitat for feeding, nesting, and roosting. Continued monitoring is important to detect any future population declines that might warrant increased protection for this distinctive wading bird.