Atitlán Grebe
Encyclopedia
The Atitlán Grebe also known as Giant Grebe, Giant Pied-billed Grebe, or Poc, is an extinct water bird, a relative of the Pied-billed Grebe
. It was endemic at the Lago de Atitlán
in Guatemala
at an altitude of 1700 m asl. Thanks to the field work of the American ecologist Anne LaBastille
, its decline is comprehensively known. LaBastille observed this species for a period of over 25 years. She has also written a book about this bird called Mama Poc.
(Micropterus dolomieu) and Largemouth bass
(Micropterus salmoides) were introduced into Lake Atitlán. These invasive species
reduced the crabs and fish which the grebes depended on for food and the fish even killed the grebe chicks. The population of the Atitlán Grebe declined from 200 individuals in 1960 to 80 in 1965. Thanks to the conservation efforts of Anne LaBastille, in 1966 a refuge was established where this species was able to rebound. The population recovered to 210 in 1973. Unfortunately after the 1976 Guatemala earthquake
, the lake bed fractured. An underwater drain led to a fall of the water level and to a further severe decrease of the number of grebes. In 1983 only 32 individuals were left, of which the largest part were hybrids with the Pied-billed Grebe. The last two birds were seen in 1989, and after they disappeared the Atitlán Grebe was declared officially extinct.
Pied-billed Grebe
The Pied-billed Grebe is a species of the grebe family of water birds. Since the Atitlán Grebe, Podilymbus gigas, has become extinct, it is the sole extant member of the genus Podilymbus.-Description:...
. It was endemic at the Lago de Atitlán
Lago de Atitlán
Lake Atitlán is a large endorheic lake in the Guatemalan Highlands. Atitlan is recognized to be the deepest lake in Central America with maximum depth about 340 meters. The lake is shaped by deep escarpments which surround it and by three volcanos on its southern flank...
in Guatemala
Guatemala
Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast...
at an altitude of 1700 m asl. Thanks to the field work of the American ecologist Anne LaBastille
Anne LaBastille
Anne LaBastille was an American author and ecologist. She was the author of more than a dozen books, including Woodswoman, Beyond Black Bear Lake, Woodswoman III, Woodswoman IIII, Assignment:Wildlife, and Women of the Wilderness. She also wrote more than 150 popular articles and over 25 scientific...
, its decline is comprehensively known. LaBastille observed this species for a period of over 25 years. She has also written a book about this bird called Mama Poc.
Description
The Atitlán Grebe reached a length of about 46–50 cm. The call and appearance were similar to the Pied-billed Grebe. The plumage was mainly dark brown with white-flecked flanks. The underparts were dark grey flecked with white. The head was almost black and the neck was flecked with dark brown in the spring and white in the winter. The legs were slaty grey. The bill had a bold black vertical band in the middle. The color of the bill varied from white in the spring to brown in other seasons. The irises were brown. It had small wings and was flightless.Reproduction
The nest consisted of 4 to 5 white eggs. Both parents shared the rearing of the hatchlings.Extinction
The decline of the Atitlán Grebe began in 1958 and again in 1960 after Smallmouth bassSmallmouth bass
The smallmouth bass is a species of freshwater fish in the sunfish family of the order Perciformes. It is the type species of its genus...
(Micropterus dolomieu) and Largemouth bass
Largemouth bass
The largemouth bass is a species of black bass in the sunfish family native to North America . It is also known as widemouth bass, bigmouth, black bass, bucketmouth, Potter's fish, Florida bass, Florida largemouth, green bass, green trout, linesides, Oswego bass, southern largemouth...
(Micropterus salmoides) were introduced into Lake Atitlán. These invasive species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
reduced the crabs and fish which the grebes depended on for food and the fish even killed the grebe chicks. The population of the Atitlán Grebe declined from 200 individuals in 1960 to 80 in 1965. Thanks to the conservation efforts of Anne LaBastille, in 1966 a refuge was established where this species was able to rebound. The population recovered to 210 in 1973. Unfortunately after the 1976 Guatemala earthquake
1976 Guatemala earthquake
The 1976 Guatemala earthquake struck on February 4, 1976 at 03:01:43 local time . It was a 7.5 Mw earthquake, centered in the Motagua Fault, about 160 km northeast of Guatemala City, Guatemala...
, the lake bed fractured. An underwater drain led to a fall of the water level and to a further severe decrease of the number of grebes. In 1983 only 32 individuals were left, of which the largest part were hybrids with the Pied-billed Grebe. The last two birds were seen in 1989, and after they disappeared the Atitlán Grebe was declared officially extinct.
See also
- Alaotra GrebeAlaotra GrebeThe Alaotra Grebe , also known as Delacour's Little Grebe or Rusty Grebe, was a grebe endemic to Lake Alaotra and surrounding lakes in Madagascar. The last sighting was in 1985 and the species was declared extinct in 2010...
, probably extinct since the late 1980s for analogous reasons. - Colombian GrebeColombian GrebeThe Colombian Grebe , was a grebe found in the Bogotá wetlands in the Eastern Andes of Colombia. The species was still abundant on Lake Tota in 1945. The species has occasionally been considered a subspecies of Black-necked Grebe The Colombian Grebe (Podiceps andinus), was a grebe (aquatic...