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Harvest records reveal that populations of bobcats (Lynx rufus) in New Hampshire have undergone substantial changes during the past 200 years. In the 1800s, a nearly continuous bounty program resulted in annual harvests that averaged ∼30 bobcats. Harvests increased in 1915, and fluctuated from 100 to 400 bobcats during the 1920s through the 1950s. In 1959, harvests peaked at 421 and then rapidly declined. By 1970, payment was made on only 10 bobcats, and legal status was changed from nuisance animal to game species in 1973. In 1989, trapping and hunting seasons were closed and bobcats were designated a protected species. After 15 years of protection, populations of bobcats seem to be remaining at modest levels. To understand what factors may have contributed to the remarkable rise and fall of bobcat populations, we compared the temporal distribution of harvests to comments by early naturalists, legislation to control bobcat abundance, and historical changes in land use. We then used two approaches with a geographic information system to identify the environmental features that may affect present-day populations. The empirical approach relied on a comparison of landscape characteristics associated with recent (1990–2004) observations of bobcats to characteristics found at a comparable set of random locations. We also examined the characteristics of townships that yielded the majority of historical bobcat harvests (1931–1965) and developed a process-oriented model to rank present-day habitat suitability. The irruption of bobcat populations coincided with the availability of early-successional habitats as abandoned agricultural lands reverted to second-growth forests during the first half of the 20th century. Likewise, bobcat populations rapidly declined as these forests matured and no longer supported abundant prey, especially New England cottontails (Sylvilagus transitionalis). Our efforts to identify habitat features associated with present-day populations had mixed results. The empirically derived model correctly classified only 52% of recent bobcat locations, whereas the process-oriented model indicated that nearly 88% of recent bobcat observations were associated with sites that were ranked at high suitability. The results of this study demonstrate the utility of information on historical harvests when addressing questions on the status of contemporary wildlife populations.

Reliable estimates of status and population trend are critical for conservation of large terrestrial carnivores, but are usually lacking due to the high costs of sampling across large geographic areas. For detecting population trends of mountain lion Felis concolor californica, we evaluated counts of track sets on 48 randomly chosen quadrats in California. Each quadrat contained 33.8 km of transect on dusty, dirt roads, which were chosen by local wildlife biologists. A count of track sets by one person on all quadrats was more efficient than recording presence/absence by local survey teams. We estimated an efficient sample size of 44 quadrats in California after applying our data to a general formula for contagious distributions. This sample size can be reduced substantially by choosing new transect locations based on associations of tracks with topography and habitat. Tracks were most likely found on roads along 1st- and 2nd-order streams, on mountain slopes and knolls/peaks and in oak woodland and montane hardwood conifer forest. A changing mountain lion population can be detected with an inexpensive, periodic track survey and self-stratifying, non-parametric tests. Each track survey across California can be finished in 30 days. The many mountain lions and the variety of environmental conditions included at this extraordinarily large spatial scale permit estimates of: (1) trends among population strata in quadrats that are clustered according to typical number and age/sex class of track sets; (2) population size and demography after individuals are identified by their tracks, and after linear density on roads is calibrated from spatial density at intensive study, sites: and (3) spatio-temporal associations with bobcat Felis rufus, black bear Ursus americanus, coyote Canis latrans, and fox Vulpes vulpes and Urocyon cinereoargenteus.