Development and application of a spatially explicit moose population model

We developed spatially explicit models of moose (Alces alces) population de nsity for the province of Ontario using the geostatistical technique krigin g. The models were based on moose surveys divided into four time periods fr om 1975 to 1995. Density change was calculated for the 1975-1979, 1980-1984 , 1985-1989, and 1990-1995 time periods to visualize regional trends in pop ulation change. Between 1975 and 1995, moose density increased in the north west and southeast parts of the province and decreased in some northern poc kets. A marked increase in density occurred in the late 1980s, when both th e selective moose harvest system and moose habitat guidelines were introduc ed in Ontario. Although a general increase in survey effort occurred in abo ut 1986, no effect of survey effort was detected on moose population change between the first and last time periods (P = 0.215). To evaluate the possi ble effect of reducing number of survey plots on density estimates, we recr eated density maps by using 25, 50, and 75% of the original data and compar ed the full-data maps with the reduced-data maps. The regression slopes and r(2) for reduced-data versus full-data maps approached 1.0 as sample rate increased from 25 to 75% (B = 0.88, 0.86, and 0.96; r(2) = 0.82, 0.88, and 0.95). A K analysis also suggests an acceptable performance of the 75% data map (re = 0.716).