Florida Scrub Jay: Threatened by Shrinking HabitatSep 07, 2021 05:00PM ● By WILLIAM R. COX
Historically, the range of the Florida scrub jay (Aphelocoma coerulescens) was scattered in that part of the Florida peninsula associated with fragmented scrub habitat. Only 60 percent of its original population exists today because of destruction of its habitat by fire suppression, suburban development, citrus conversion and other agriculture operations. Florida scrub may be the state’s most endangered habitat, as it is prime land for development. The recovery of Florida’s endangered plants and animals depends upon the knowledge and actions of Florida residents and visitors.
The scrub jay’s current range includes scattered subpopulations from northern Collier County northward to Clay County. The state population is estimated to be 7,000 to 11,000 birds, mostly found in Merritt Island National Wildlife Refuge in Brevard County, Ocala National Forest and in the uplands north and west of Lake Okeechobee.
The U.S. Fish and Wildlife Service federally listed the Florida scrub jay as threatened in 1987. The Florida Fish and Wildlife Commission listed it as endangered in the state in 1972, but upgraded its status to threatened in1975.
The Florida scrub jay is extremely habitat specific, requiring oak scrub less than 10 feet tall associated with areas of bare sand. Taller vegetation such as turkey oak and sand pine must consist of less than 50 percent canopy cover for suitable scrub jay habitat.
Oak scrub habitat includes well-drained white, fine, siliceous sands that were deposited during the Pleistocene high sea-level era. Some of the common oaks comprising scrub include Chapman oak, myrtle oak and sand live oak. Other vegetation often associated with scrub includes sand pine, turkey oak, rosemary, saw palmetto, crookedwood and silk bay. The different Florida oak scrubs can be categorized as rosemary, turkey oak, palmetto, sand pine and scrubby pine flatwoods.
The Florida scrub jay has blue upperparts, a gray back, gray underparts, a blue-gray streaked breast, white throat, whitish forehead and dark eye-ear patch. It is 11 inches long.
It is sexually mature at one year of age, though females older than five years of age produce more than 50 percent of the offspring. Sexual vigor peaks at four years but remains high up to age 14.
The Florida scrub jay is monogamous. Breeding pairs normally produce only one clutch per breeding season. The breeding unit size is usually three, including one nonbreeding adult called a helper. Some breeding units may include six helpers. Breeding pairs with helpers that bring food to the nestlings and defend territories yield more young per year.
In courtship the male hops or walks around the female in an arc with his tail fanned out and dragging on the ground. He sometimes gently nibbles at her toes. Copulation is infrequent and secretive. The breeding season averages 90 days, sometime between early March and late June.
Sand live oaks are preferred for nesting, but others such as myrtle oak may be selected. The nest is placed three to six feet above the ground in shade at the edge of a clump of dense shrub. It averages six to seven inches in diameter and is made of oak twigs and lined with sabal palmetto fibers. Both sexes build the nest and attend the young, but the female does all the incubating and brooding. The male brings her food during this time. Clutch size is two to five greenish, brown-spotted eggs, and incubation takes 18 days. Fledging averages 18 days after incubation with a range of 12-25 days.
Predators of eggs and adults include the eastern coachwhip and eastern indigo snakes. Raptors and bobcats prey on adults.
The Florida scrub jay is an omnivore, with 40 percent of its food being plant material and 60 percent animal material. Examples include acorns, berries, seeds, fruits, spiders, ants, wasps, grasshoppers and beetles. I have seen them take small reptiles, amphibians and nestlings. It spends considerable time from late summer through December eating and caching acorns in open sandy areas.
Territory for the nonmigratory scrub jay can persist for years. It is well defined and defended all year. Territory size averages 25 acres, and density ranges from two to six birds per 100 acres.
Other Florida locations to observe scrub jays, in addition to those already mentioned, include Archbold Biological Station near Lake Placid, Cape Canaveral Space Force Station, Blue Spring State Park, Jonathan Dickinson State Park and Oscar Scherer State Park. The best time to observe these birds is early to mid-morning during nesting season from March through June.
Recovery of this threatened species and its habitat depends on people learning about them, teaching others and supporting public facilities that preserve and manage this unique bird.
William R. Cox has been a professional nature photographer and ecologist for more than 35 years. Visit him online at williamrcoxphotography.com.