New Mexico black bear conservation

The black bear is the most widely distributed bear species in North America.  Following human-caused population declines, many black bear populations have increased during the last 75 years.  Today, black bears inhabit much of their former range and most populations are sufficiently abundant to be managed as game species, with hunting regulations determined by state or provincial agencies. 

The Human Aspect
Black bears easily adapt to humans and this is the likely reason for the persistence of black bears in regions where grizzlies were extirpated.  However, hunter preference for large adult males, coupled with management strategies for protecting reproductive females, may serve to distort the natural population structure.  This alteration may affect the natural regulatory processes governing bear populations and may produce greater potential for bear-human conflict by causing increased immigration in sub-adult males.

Threats
Management of black bears must balance positive values of bear-human interactions, including wildlife viewing and hunting, with negative aspects, such as nuisance problems, crop and livestock depredation, and bear-inflicted human injuries.  With expanding human populations, management of these bear-human interactions will only become more challenging.

WCS Activities
Between 1992 and 2000, WCS researchers and agency cooperators gathered data critical to understanding black bear ecology and population dynamics during the first phase of this two-part project.  Fieldwork was conducted in two distinct regions of New Mexico, where each population contended with unique habitat and human challenges.  Field data were collected using capture, den investigation, and radio-telemetry techniques.  We obtained abundant information on survival, reproduction, population characteristics, movements, home range, denning, and habitat use.
The second phase seeks to synthesize and communicate this information.  Through genetic analyses of samples collected in the field, we are investigating the relationship between hunting, black bear population structure, and human-black bear conflict.  Research outcomes will improve understanding of black bear ecology and management in New Mexico.  Using the new tools provided by this study, as well as existing tools, managers can evaluate the results and consequences of management alternatives and assess past, current, and future trends in bear populations. 

Important Next Steps

• Use DNA microsatellite analysis to determine kin relationships (including maternity and paternity) among nearly 500 bears captured during the 8-year field study.
• Examine interrelationships of kinship, sex-age composition, density, immigration, dispersal, and spatial organization.
• Investigate possible link between selective hunting mortality and subadult immigration on incidence of bear-human conflict.
• Provide this information to key audiences to enable better conservation management practices.

Selected and representative publications

Peer-reviewed journal publications
Inman, R. M., C. M. Costello, D. E. Jones, K. H. Inman, B. C. Thompson,
      H. B. Quigley.  Submitted.  Denning chronology and hunter harvest of
      black bears in New Mexico.  Journal of Wildlife Management 0:0-0. 
Costello, C. M., K. H. Inman, D. E. Jones, R. M. Inman, B. C. Thompson,
      H. B. Quigley.  In Press. Reliability of the cementum annuli technique
      estimating age of   black bears in New Mexico.  Wildlife Society Bulletin 0:0-0.
Costello, C. M., D. E. Jones, R. M. Inman, K. H. Inman, B. C. Thompson,
      H. B. Quigley.  2003.  Relationship of variable mast production to American
      black bear reproductive parameters in New Mexico.  Ursus 14:1-16.
Costello, C. M., R. M. Inman, K. L. Higgins, D. E. Jones, H. B. Quigley,
      and S. L. Simek.  2001.  Comparison of an expandable radio-collar and an
      ear-tag transmitter for monitoring juvenile black bears.   Western Black
      Bear Workshop.  7:17.