Dusky Seaside Sparrow
Encyclopedia
The Dusky Seaside Sparrow, Ammodramus maritimus nigrescens, was a non-migratory
subspecies
of the Seaside Sparrow
, found in Southern Florida
in the natural salt marshes of Merritt Island and along the St. Johns River
. The last definite known individual died on June 17, 1987 and the species was officially declared extinct in December 1990.
was sprayed on the marshes for the control of mosquitoes. This pesticide entered the bird's food chain which caused the population to go from 2,000 to 600 breeding pairs. When Merritt Island was flooded with the goal of reducing the mosquito
population around Kennedy Space Center
, the sparrows' nesting grounds were devastated, and their numbers plummeted. Later, the marshes surrounding the river were drained, to facilitate highway construction; this was a further blow. Eventually, pollution and pesticides took such a high toll that by 1979, only six dusky seaside sparrows were known to exist — all of whom were males; a female was last sighted in 1975.
of all remaining dusky seaside sparrows with the Scott's Seaside Sparrow
(A. m. peninsulae) from Florida's gulf coast was approved in 1979. By 1980 five dusky seaside sparrows were in a captive breeding facility in Gainesville, Florida. One, banded in 1978 with an orange leg band was unique.
"Orange Band" was left by himself on the St. Johns Unit of the St. Johns NWRhttp://www.fws.gov/refuges/profiles/index.cfm?id=41573 after a yellow leg banded dusky was captured in 1979. Field observations of color banded sparrows from 1975 to 1979 indicated that dusky seaside sparrows seldom traveled more than a mile or two in their lifetimes. In April 1980, "Orange Band" was again observed on the St. Johns Unit, but was surprisingly captured in June eight miles south on the Beeline Unit in the company of a dusky with a green leg band. Before finding "Green Band", "Orange Band" passed the general vicinity of the two unbanded dusky seaside sparrows.
In 1983 the last four living dusky seaside sparrows were taken to Walt Disney World Resort
, to continue crossbreeding and living out their days in a protected habitat on the Discovery Island nature reserve. By March 31, 1986, only "Orange Band" remained.
Despite being blind in one eye, "Orange Band" reached extreme old age for a sparrow, living at least nine years, and possibly as many as thirteen, before dying on June 17, 1987.
"Green Band" proved elusive, and was never recaptured after having been banded. He was last seen on July 23, 1980 (Walters 1992).
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
of the Seaside Sparrow
Seaside Sparrow
The Seaside Sparrow, Ammodramus maritimus, is a small American sparrow. The 11 Ammodramus species inhabit marshes and grasslands.Adults have brownish upperparts with grey on the crown and nape, and a grayish buff colored breast with dark streaks; they have a dark face with grey cheeks, a white...
, found in Southern Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
in the natural salt marshes of Merritt Island and along the St. Johns River
St. Johns River
The St. Johns River is the longest river in the U.S. state of Florida and its most significant for commercial and recreational use. At long, it winds through or borders twelve counties, three of which are the state's largest. The drop in elevation from the headwaters to the mouth is less than ;...
. The last definite known individual died on June 17, 1987 and the species was officially declared extinct in December 1990.
Causes for extinction
The dusky's demise began in 1940 when DDTDDT
DDT is one of the most well-known synthetic insecticides. It is a chemical with a long, unique, and controversial history....
was sprayed on the marshes for the control of mosquitoes. This pesticide entered the bird's food chain which caused the population to go from 2,000 to 600 breeding pairs. When Merritt Island was flooded with the goal of reducing the mosquito
Mosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
population around Kennedy Space Center
Kennedy Space Center
The John F. Kennedy Space Center is the NASA installation that has been the launch site for every United States human space flight since 1968. Although such flights are currently on hiatus, KSC continues to manage and operate unmanned rocket launch facilities for America's civilian space program...
, the sparrows' nesting grounds were devastated, and their numbers plummeted. Later, the marshes surrounding the river were drained, to facilitate highway construction; this was a further blow. Eventually, pollution and pesticides took such a high toll that by 1979, only six dusky seaside sparrows were known to exist — all of whom were males; a female was last sighted in 1975.
Last specimens
Captive breedingCaptive breeding
Captive breedingis the process of breeding animals in human controlled environments with restricted settings, such as wildlife reserves, zoos and other conservation facilities; sometimes the process is construed to include release of individual organisms to the wild, when there is sufficient...
of all remaining dusky seaside sparrows with the Scott's Seaside Sparrow
Scott's Seaside Sparrow
Scott's Seaside Sparrow is a subspecies of the Seaside Sparrow. It can be found along the Gulf of Mexico coast of northwestern Florida, where it breeds from Pasco County to Apalachee Bay and in the swamplands of St. George and St. Vincent islands. It was originally thought to be a separate species...
(A. m. peninsulae) from Florida's gulf coast was approved in 1979. By 1980 five dusky seaside sparrows were in a captive breeding facility in Gainesville, Florida. One, banded in 1978 with an orange leg band was unique.
"Orange Band" was left by himself on the St. Johns Unit of the St. Johns NWRhttp://www.fws.gov/refuges/profiles/index.cfm?id=41573 after a yellow leg banded dusky was captured in 1979. Field observations of color banded sparrows from 1975 to 1979 indicated that dusky seaside sparrows seldom traveled more than a mile or two in their lifetimes. In April 1980, "Orange Band" was again observed on the St. Johns Unit, but was surprisingly captured in June eight miles south on the Beeline Unit in the company of a dusky with a green leg band. Before finding "Green Band", "Orange Band" passed the general vicinity of the two unbanded dusky seaside sparrows.
In 1983 the last four living dusky seaside sparrows were taken to Walt Disney World Resort
Walt Disney World Resort
Walt Disney World Resort , is the world's most-visited entertaimental resort. Located in Lake Buena Vista, Florida ; approximately southwest of Orlando, Florida, United States, the resort covers an area of and includes four theme parks, two water parks, 23 on-site themed resort hotels Walt...
, to continue crossbreeding and living out their days in a protected habitat on the Discovery Island nature reserve. By March 31, 1986, only "Orange Band" remained.
Despite being blind in one eye, "Orange Band" reached extreme old age for a sparrow, living at least nine years, and possibly as many as thirteen, before dying on June 17, 1987.
"Green Band" proved elusive, and was never recaptured after having been banded. He was last seen on July 23, 1980 (Walters 1992).
External links
- Earth Witness Community — Dusky Seaside Sparrow
- History of the Merritt Island National Wildlife Refuge
- Florida Bird Sounds — contains a sound of Dusky Seaside Sparrow and other birds of Florida.