Woodpeckers are excellent indicators of ecosystem health.
Nine woodpecker species are included in this richness map (Acorn Woodpecker, Williamson’s Sapsuckers, Red-breasted Sapsuckers, Ladder-backed, Nuttall’s, Downy, Hairy, White-headed Woodpeckers, and Northern Flicker).
As cavity nesters, woodpeckers have historically required living and dead native trees (e.g. oaks, sycamores, walnuts, pines) in which to excavate space to build their nests. High woodpecker species richness can thus be seen in the forest habitat of the San Gabriel Mountains. But the map also reveals a large swath of southern Los Angeles County with little or no breeding woodpeckers. Dense urban areas typically offer fewer nesting opportunities, as dead or dying trees usually need to be removed due to safety hazards. However, woodpeckers play an important role in their ecosystems; they are often referred to as “ecosystem engineers” because their excavation activities significantly modify ecosystems and allow other species to benefit from their work. Once abandoned, woodpecker cavities are often used by many other birds and mammals, including owls, swallows, bluebirds, and squirrels. The preservation of snags (dead trees) for woodpecker nesting is thus important in natural areas, parks, and other green spaces and rights-of-way wherever possible.
Los Angeles County Breeding Bird Survey © LA Audubon 2016
About this map:
The data in this map has been adapted from the Breeding Bird Atlas, a Los Angeles Audubon Society publication created by Larry W. Allen and Kimball L. Garrett, with maps compiled by Mark C. Wimer. The Breeding Bird Atlas includes data for over 200 breeding bird species in Los Angeles County, based on fieldwork conducted from 1995 to 1999. Over 300 volunteer observers contributed 10,000+ hours to gather more than 28,000 records.
The Breeding Bird Atlas is an excellent model of systematic biodiversity research and surveys. The book contains summaries of breeding bird distributions, habitat requirements, and important conservation indicators (abundance, population trends), as well as maps of confirmed and suspected breeding locations. The Biodiversity Atlas presents summaries of the data at a 10- by 10-kilometer spatial resolution.