Florida Coastal Islands Sanctuaries
Dave Kandz

Alafia Bank Sanctuary (Bird Island to the east; Sunken Island to the west) is located in Hillsborough Bay at the mouth of the Alafia River. These two manmade islands were formed from spoil material when a channel that connects the main Tampa shipping channel to the Alafia River was dredged in the late 1920s. The islands were immediately important as bird nesting sites for gulls, terns, and skimmers. As shrubs and trees replaced low-lying vegetation, nesting herons, egrets, ibis, and later pelicans moved from the historic nesting site at Green Key. Today the islands are owned by Cargill Fertilizer, Inc. and leased to Audubon for operation as a sanctuary. Each year, up to 18,000 nesting pairs of 16 to 20 species of birds nest on the Alafia Bank Sanctuary, making it one of the largest colonies in Florida and one of the most diverse colonies in the continental United States. The Florida Fish & Wildlife Conservation Commission has listed Alafia Bank as the most important colony in the state, due to its size (number of birds nesting), longevity of nesting activity, and species diversity.

A 12-acre "Alafia Extension" was added to the west end of Sunken Island in 1977, using material from a nearby dredging project. Planted with smooth cordgrass (Spartina alterniflora) and now grown up to tall mangroves, with tidal pools, sand and mud flats, and even small creeks and salt barrens, the extension provides safe nesting, feeding, and loafing habitats for breeding and migratory birds.

Green Key and Whiskey Stump Key, also in Hillsborough Bay, are the original Tampa Bay Sanctuary islands. Protected since 1934, the birds of Green Key moved to the Alafia Bank islands in the 1960s. A handsome mangrove island, Green Key today provides important foraging and loafing habitats for birds. The seagrass meadows and oyster bars around the key are excellent bird feeding sites. Whiskey Stump Key, a quarter-mile away, was the site of the warden's residence from 1934 until the 1960s. In a quiet stand of cabbage palms on this natural island stands a monument erected in memory of Dr. H.R. Mills, a Tampa pathologist who was the driving force behind the establishment of the Sanctuary and for many years its strongest supporter.

Nina Griffith Washburn Sanctuary is located in Terra Ceia Bay. Protected by Audubon wardens since 1939 and now owned by the Society, this beautiful natural mangrove key supports a large breeding colony up to 4000 pairs of pelicans, cormorants, anhingas, herons, egrets, ibis, and spoonbills. With 16 nesting species, this colony is ranked the second most important in Florida by the Wildlife Commission.

Cortez Key Sanctuary in northern Sarasota Bay was leased by Audubon from the state in 1981. Cortez Key is home to over 600 pairs of pelicans, cormorants, herons, ibis, and this year, for the first time on record , three pairs of Roseate Spoonbills. This marks the first nesting of this species in Sarasota Bay since the 1870s. The lovely mangrove island is surrounded by shallow seagrass meadows, valuable fish nursery habitat. Several hundred Magnificent Frigatebirds roost at Cortez Key during the spring and summer.

Whale Key and the Town Islands in Sarasota Bay have been protected by the Audubon Society since 1974 through a lease from the state. These lovely mangrove islands and their surrounding shallow seagrass meadows provide excellent feeding and resting habitats for birds.

The Dot-Dash Colony at the mouth of the Braden River consists of three small mangrove islands (Dot, Dash and Dit!) and is the home of the only coastal colony of Wood Storks in the Tampa Bay area. In 2000 there were 140 pairs of storks among the 1000 pairs of wading birds present.

Just south of Sarasota, the three tiny Roberts Bay Islands are an important colony for 800-1000 pairs of Brown Pelicans, Great Blue Herons, and Great Egrets. The Roberts Bay Islands are managed by the Sanctuary with permission of the Florida Division of State Lands. Sarasota Audubon Society has "adopted" the Roberts Bay Islands as a Project ColonyWatch site. The chapter activity there has substantially raised recognition of this locally important bird colony. Sarasota High School ecology students participate in nesting surveys and fishing line removal projects.

Sand Key West in northern Clearwater Harbor is the site of a small colony of pelicans, herons and egrets. This island has deteriorated in recent years due to shoreline erosion.

Marker 26 is a rocky spoil island in St. Joseph Sound dominated by Brazilian pepper. But the pepper provides a nesting substrate that can tolerate an amazing amount of guano abuse from some 300 pairs of nesting cormorants, egrets, herons, and ibis. Marker 26 is the northernmost nesting site of Reddish Egrets on Florida's west coast.

Colony Name Breeding Pairs
(Spring 2000)
Nesting Species
(Spring 2000)
Imperiled
Species
Alafia Bank Sanctuary 7315 16 8
Washburn Sanctuary (Terra Ceia Bird Key) 1688 16 7
Cortez Key Sanctuary 648 13 7
Dot-Dash 1571 10 6
Roberts Bay 683 9 4
Sand Key/Clearwater Harbor 83 6 3
Marker 26/St. Joseph Sound 280 11 6
I-25, Clearwater Harbor 720 14 8
S. Clearwater Harbor (3 spoil islands) 339 3 2
Indian Rocks Beach Indian Rocks Beach South 128 8 3
Dogleg Key 543 9 4
Other islands managed by the Florida Coastal Islands Sanctuaries are Green Key, Whiskey Stump Key, Whale Key, the Town Islands, Sand Key East, and Ozona Spoil Island East. These islands are included in the sanctuary either because they have been important bird colonies in the past, because they provide excellent foraging habitat, or both.
Copyright  2013 National Audubon Society, Inc