Range maps

Last year, James K. Sheppard won an award for his 3-dimensional map of the space utilized by a single California condor. This remarkable map was made possible by data obtained from a global positioning system (GPS) device attached to the condor’s wing. Developing the map required complex analysis performed on a supercomputer, plus artistic talent.

Sheppard’s remarkable map, and all the winners of the BMC Ecology Image Competition 2015, can be seen here.

Maps such as Sheppard’s have become possible thanks to new technologies. In the past, information showing where a species of bird lives was often presented only in words.

For example, Roger Tory Peterson’s A Field Guide to Western Birds did not include range maps in the 1st (1941) or 2nd (1961) editions. The 3rd edition (1990) does include maps showing where bird species breed, winter, and are resident year-round. But there is no such map for the California condor. All condors were in captivity at this time. There is only a 1-sentence description of their former range. (The 1st 3 editions of Peterson’s guide were published by Houghton Mifflin.)

In recent years, range maps have become more common. Even the typical maps that show range in 2 dimensions can convey a great deal of valuable information about where birds live.

To demonstrate the variety of range maps and how they have changed through time, I present 10 maps for the California condor. These are in chronological order.

This range map from 1925, like Sheppard’s, shows the California condor living in Baja California:
01 Wyman & Burnell 1925
Cartographers: Mary A Burnell and Mildred E Sykes. Source: Wyman, Luther E, and Elizabeth F Burnell. Field book of birds of the southwestern United States. Houghton Mifflin. 1925.

A map from the 1st major study of the California condor provides details about condors’ use of space:
02 Koford 1953
Cartographer: Not credited. Source: Koford, Carl B. The California condor. National Audubon Society. 1953.

Koford’s caption explains that this map is for the period 1935 to 1950 and that:

Groups of ten or more Condors occur in the area enclosed by the heavy line. Cross-hatching indicates breeding areas; spots, major roosts; radiating lines, major routes of flight.

Next is a map was developed to communicate the methods and results of the 1st major effort to census condors:
03 Mallette & Borneman 1966
Cartographer: Cliffa Corson. Source: Mallette, Robert D, and John C Borneman. First cooperative survey of the California condor. California Fish and Game. July 1966.

In addition to showing the historic and present range of California condor, this hemispheric map shows the range of the Andean condor (solid dark shading):
04 Brown & Amadon 1968
Cartographer: Not credited. Source: Brown, Leslie, and Dean Amadon. Eagles, hawks, and falcons of the world. Volume 2. McGraw-Hill. 1968.

This information-rich map indicates 3 condor nesting areas and the seasonal and year-round ranges of 2 condor populations and a 3rd subpopulation:
05 Wilbur et al 1979
Cartographer: Not credited. Source: Wilbur, Sanford R, and others. California condor recovery plan. US Fish and Wildlife Service. 1979.

The caption for the map below begins: “The Late Pleistocene range of the California Condor.” Locations where California condor fossils have been found are shown and include New York, Florida, Texas, New Mexico, Arizona, Nevada, and California. The caption indicates that 2 locations in Mexico are not shown.
06 Steadman & Miller 1987
Cartographer: Not credited. Source: Steadman, David W, and Norton G Miller. California condor associated with spruce-jack pine woodland in the Late Pleistocene of New York. Quaternary Research. November 1987.

This map dates from the time when all condors were in captivity and so only the former range can be shown:
07 Cassidy 1990
Cartographer: John Dawson. Source: Cassidy, James, editor. Book of North American birds. Reader’s Digest. 1990.

Based on my understanding, the next map incorrectly extends the historical range of the California condor much too far east:
08 McGlathery & Livo 1992
Cartographer: David Stallings. Source: McGlathery, Glenn, and Norma J Livo. Who’s endangered on Noah’s ark? Literary and scientific activities for teachers and parents. Teacher Ideas. 1992.

The release of captive-bred condors into northern Arizona is reflected in the map below. At last, a reversal in the long decline of the condor’s range!
09 Ward 2004
Cartographer: Not credited. Source: Ward, Adam. Endangered animals. Sterling. 2004.

Finally, here is the range map from the most recent edition of Peterson’s western bird guide:
10 Peterson 2010

Cartographer: Paul Lehman. Source: Peterson, Roger Tory. Peterson field guide to birds of western North America. 4th edition. Houghton Mifflin Harcourt. 2010.

So now we have a range map showing condors in California, Arizona, Utah, and Mexico (the site of the most-recent reintroductions). Perhaps it will not be too many years before maps show condors living again in the Pacific Northwest.