TEMPORAL AND SPATIAL DYNAMICS OF IXODES-SCAPULARIS (ACARI, IXODIDAE) IN A RURAL LANDSCAPE

We studied seasonal, interannual, and both small- and large-scale spat ial variation in the abundance of blacklegged ticks, Ixodes scapularis Say, in a semirural landscape in southeastern New York. Using transec t drag sampling, we found that ticks were approximately twice as abund ant in 1994 as in the preceding 2 yr. In 1994, larval ticks showed a s trong peak in activity in late spring, coincident with the nymphal pea k that year. All post-egg life stages were more abundant in forested t han in shrubby or herbaceous habitat types, but peak abundance of larv ae shifted from oak-dominated forest in 1992 to maple-dominated forest in 1993 and 1994. All life stages were highly clumped at small spatia l scales, but larvae were the most aggregated. Within the forested hab itat types, we observed an initial increase followed by a decrease in small-scale clumping during seasonal activity for each life stage. We discuss potential effects of the observed temporal and spatial variati on on risk of Lyme disease. Because of pronounced variation in abundan ce and activity patterns among years and habitat types, we caution aga inst generalizing from short-term or spatially limited studies.