California Department of Fish and Wildlife

Long Term Trends in California's Deer Population

The graph below is a general representation of deer populations in California since 1800 and highlights a few of the significant events that have affected deer. During the period around 1850-1920, California wildlands were subject to high disturbance from logging, mining, fire, and grazing. These disturbances led to increased acreages of early successional vegetation (new, young plants) that deer thrive on. Deer populations increased to where overuse of range by deer became evident starting in the early 1930s. Since that time, with increased fire suppression and declining disturbance from mining, etc., the vegetation has matured and is not capable of supporting the previous high numbers of deer.

These changes began to show in the 1930s, with deer populations not reaching their peak until the 1960s. Dr. Tracy Storer, a noted ecologist from the University of California, had predicted such a change in a 1932 paper published in Ecology. The changes have not been instantaneous, rather, have taken several decades to become evident. This adds to the difficulty in making short-term predictions about wildlife populations.

Department biologists believe that long-term declines in habitat condition, starting in the 1930s and continuing today, are most responsible for the decline. Lack of habitat disturbance, especially from fire, has decreased habitat value for deer and other wildlife in much of the state's forested areas. Deer and numerous other wildlife thrive on early successional (seral) vegetation that grows back in the first few years after fire. Without periodic fire, the habitat becomes old, or “decadent,” and is unable to support wildlife populations of the past. Indirect consequences, such as increasing competition with livestock and overuse of ranges by deer themselves, are typical. Deer hunters can also attest that fewer deer in the woods is also result.

“Abundant” refers to deer populations of 700,000-1,000,000; “Common” refers to deer populations between 400,000-700,000; and “Scarce” refers to populations lower than 400,000 animals.



Deer trends in California