Meet The Incredible White-Winged Fairywren Bird
The area of occupancy is estimated, with high reliability, to be 200 km². There is no evidence of a historical change in the area of occupancy. The area of occupancy is currently stable (Garnett & Crowley 2000).
The White-winged Fairy-wren (Dirk Hartog Island) occurs at a single location, Dirk Hartog Island, in Western Australia (Schodde & Mason 1999).
The White-winged Fairy-wren (Dirk Hartog Island) is considered to be widespread on Dirk Hartog Island (Johnstone & Storr 2004; Wells & Wells 1974; Whitlock 1921), where it occurs in most habitats (Garnett & Crowley 2000). On the basis of this information, it is presumed that its distribution is not severely fragmented.
The population size of the White-winged Fairy-wren (Dirk Hartog Island) has been estimated twice: one estimate, considered to be of low reliability, determined the population size to be 40 000 adult birds (Garnett & Crowley 2000); a second estimate, based on probable territory sizes and the area of suitable habitat available on Dirk Hartog Island, determined the population size to be 7 000 adult birds (Brooker 2007, pers. comm.). There is evidence to suggest that the former estimate greatly overestimates the actual population size.
The White-winged Fairy-wren (Dirk Hartog Island) is restricted to Dirk Hartog Island and has an extent of occurrence of only about 200 km² (Garnett & Crowley 2000). Based on the larger population estimate of 40 000 adult birds (or 20 000 breeding pairs), each breeding pair would occupy, on average, a territory of about 1 ha in size. This seems rather small given the territories of the mainland subspecies M. l. leuconotus are known to range from about 1.5 to 6 ha in size (Higgins et al. 2001; Rowley & Russell 1995; Tidemann 1980, 1990). Considering the estimates of territory size for the mainland subspecies, and that the density of White-winged Fairy-wrens on Dirk Hartog Island is likely to be lower than on Barrow Island (which, based on field surveys, is estimated to support about 7 500 to 9 500 birds of subspecies M. l. edouardi [Bamford & Bamford 2005b; Pruett-Jones & O’Donnell 2004]) because of grazing by sheep Ovis aries and goats Capra hircus and the presence of House Mice Mus musculus and cats Felis catus on Dirk Hartog Island (Brooker 2007, pers. comm.; Garnett & Crowley 2000), the more conservative estimate of 7 000 adult birds (or 3 500 breeding pairs) was proposed (Brooker 2007, pers. comm.).
The population size of the White-winged Fairy-wren (Dirk Hartog Island) is currently stable. There is no evidence for a historical decline in population size. The White-winged Fairy-wren (Dirk Hartog Island) has persisted on Dirk Hartog Island despite the introduction of sheep, goats and cats; occasional extensive fires; and intensive grazing by sheep at the southern end of the island (Garnett & Crowley 2000).
The White-winged Fairy-wren (Dirk Hartog Island) occurs at a single location, Dirk Hartog Island, in Western Australia (Schodde & Mason 1999).
The White-winged Fairy-wren (Dirk Hartog Island) is considered to be widespread on Dirk Hartog Island (Johnstone & Storr 2004; Wells & Wells 1974; Whitlock 1921), where it occurs in most habitats (Garnett & Crowley 2000). On the basis of this information, it is presumed that its distribution is not severely fragmented.
The population size of the White-winged Fairy-wren (Dirk Hartog Island) has been estimated twice: one estimate, considered to be of low reliability, determined the population size to be 40 000 adult birds (Garnett & Crowley 2000); a second estimate, based on probable territory sizes and the area of suitable habitat available on Dirk Hartog Island, determined the population size to be 7 000 adult birds (Brooker 2007, pers. comm.). There is evidence to suggest that the former estimate greatly overestimates the actual population size.
The White-winged Fairy-wren (Dirk Hartog Island) is restricted to Dirk Hartog Island and has an extent of occurrence of only about 200 km² (Garnett & Crowley 2000). Based on the larger population estimate of 40 000 adult birds (or 20 000 breeding pairs), each breeding pair would occupy, on average, a territory of about 1 ha in size. This seems rather small given the territories of the mainland subspecies M. l. leuconotus are known to range from about 1.5 to 6 ha in size (Higgins et al. 2001; Rowley & Russell 1995; Tidemann 1980, 1990). Considering the estimates of territory size for the mainland subspecies, and that the density of White-winged Fairy-wrens on Dirk Hartog Island is likely to be lower than on Barrow Island (which, based on field surveys, is estimated to support about 7 500 to 9 500 birds of subspecies M. l. edouardi [Bamford & Bamford 2005b; Pruett-Jones & O’Donnell 2004]) because of grazing by sheep Ovis aries and goats Capra hircus and the presence of House Mice Mus musculus and cats Felis catus on Dirk Hartog Island (Brooker 2007, pers. comm.; Garnett & Crowley 2000), the more conservative estimate of 7 000 adult birds (or 3 500 breeding pairs) was proposed (Brooker 2007, pers. comm.).
The population size of the White-winged Fairy-wren (Dirk Hartog Island) is currently stable. There is no evidence for a historical decline in population size. The White-winged Fairy-wren (Dirk Hartog Island) has persisted on Dirk Hartog Island despite the introduction of sheep, goats and cats; occasional extensive fires; and intensive grazing by sheep at the southern end of the island (Garnett & Crowley 2000).
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