California is home to extensive and diverse wilderness areas, supporting a large and widely distributed population of wild bears across its forests and mountain ranges. Understanding the number of bears is important for wildlife conservation and for developing effective public safety and management strategies. Monitoring this population allows biologists to track ecosystem health and manage increasing interactions between humans and wildlife.
Identifying California’s Bear Population
The California Department of Fish and Wildlife (CDFW) estimates the current statewide population to be between 49,000 and 71,000 individuals, with a central estimate of approximately 60,000 bears. This population size is considered stable. Every wild bear currently inhabiting California is an American Black Bear (Ursus americanus). The California Grizzly Bear (Ursus arctos horribilis) was extirpated from the region by the 1920s and no longer exists in the wild within California’s borders. This means the entire population estimate is focused solely on the American Black Bear.
How Biologists Estimate Bear Numbers
Counting a mobile and elusive species like the bear requires advanced scientific techniques. Biologists now rely on an Integrated Population Model (IPM), a complex statistical framework that synthesizes data from multiple sources to produce a reliable population estimate. This approach replaced older, less precise indirect modeling methods to provide a more detailed understanding of population dynamics across the state.
Non-Invasive DNA Sampling
A primary non-invasive technique involves establishing hair snares, which are simple barbed wire enclosures that collect small samples of hair as a bear passes through the perimeter. The hair samples contain DNA, allowing researchers to identify individual bears and estimate the density of the population in a specific area. By deploying these snares across different study regions, biologists can apply capture-recapture analysis to the genetic data to calculate local abundance.
Age Structure Data
The IPM also incorporates data collected from regulated hunting practices, specifically focusing on the age structure of the harvested bears. A small premolar tooth is collected from hunter-taken bears, and the age is determined by counting growth rings, known as cementum annuli. This age-at-harvest information, combined with data from camera traps and local density estimates, allows the model to calculate survival and recruitment rates, leading to a comprehensive statewide population figure.
Geographic Range and Population Density
The bear population is not spread evenly across California, but rather concentrated in areas that offer ideal habitat, food sources, and protection. The highest density of black bears is found in the North Coast and Cascade regions, which together support about half of the state’s entire population. These areas feature extensive mixed conifer forests and diverse vegetation that provide both cover and plentiful forage.
The massive Sierra Nevada mountain range is another primary stronghold, accounting for roughly 40% of the total bear population, though the density is slightly lower than in the northern regions. Black bears occupy a wide range of environments, including forests, grasslands, and even desert edges, demonstrating their adaptability. They have also established populations in the Transverse Ranges of Southern California, such as the San Gabriel and San Bernardino Mountains.
Black bears were introduced to the San Gabriel Mountains in 1933 and have since expanded their range and numbers in Southern California. This expansion has led to an increasing presence in the urban-wildland interface, where proximity to human development can lead to conflicts over unsecured food attractants. Population density is closely tied to habitat quality and food availability.
Historical Trends and Population Stability
The current estimate of around 60,000 bears represents a significant increase from populations observed several decades ago. In the early 1980s, the statewide population was estimated to be much lower, likely around 10,000 to 15,000 individuals. This indicates the black bear population has approximately tripled over the last three decades.
This population growth can be attributed to a combination of factors, including effective wildlife management, changes in habitat use, and the species’ natural resilience. The population is now considered stable, reflecting successful conservation efforts. Management strategies, including regulated hunting, are utilized to maintain this ecological balance and prevent overpopulation in certain areas.
Since 2013, a state law banned the use of hounds for bear hunting, which has affected the annual harvest rate. This change, alongside other environmental factors, contributes to the current population dynamics. By continually monitoring population health and distribution, the CDFW aims to ensure the black bear population remains ecologically functional while mitigating human-bear interactions.