WatchList Species Account for Brewer’s Sparrow |
the list as a Declining Yellow List Species
|Photo: Greg Lavaty
In the sagebrush shrublands of the Intermountain
West, the Brewer’s Sparrow is the most abundant breeding
bird. However, the mid-1970s saw an estimated 10% decline of native
sagebrush shrublands as it was converted for agriculture and grazing.
Invasion of exotic plants, especially cheatgrass, has contributed to the decline of
this habitat type, which now occupies
millions of acres of rangeland in the West, and has greatly
increased the fire frequency.
The loss, degradation and fragmentation
of this habitat has been accompanied by a decline in the numbers
of the Brewer’s Sparrow; Breeding Bird Surveys indicate
yearly declines between 3-6% from 1966-1996.
is that factors operating on the wintering grounds may play
a role in regulating population size, but this needs further