Terrestrial arthropod biodiversity on the Kenai National Wildlife Refuge, Alaska

Abstract

"Elucidating the causes of observed patterns of living diversity remains a central goal of ecology. To understand patterns of terrestrial arthropod diversity on Kenai National Wildlife Refuge (KENWR), arthropods were collected by sweep net on 255 100m2 plots systematically distributed at 4.8km intervals across KENWR. I calculated three indices of diversity for 90 families conveying information on richness and evenness for each site. Using Bayesian Model Averaging, I found all indices were strongly influenced by site productivity, local climate, time of sampling arid plant species richness. Physiographic variables were less important than climate for determining arthropod distributions. Because many species are expected to alter their distributions in response to accelerated climate change, I assessed the use of occupancy models for monitoring those shifts on KENWR. I compared rotating panel and periodic census sampling designs using Monte-Carlo simulations given a range of occupancy and detectability values. Both designs estimated detectability within single visits and provided reasonable precision and accuracy on occupancy estimates of species with detection probabilities> 0.5, but the rotating panel design was preferred because it yielded information at shorter time intervals. I recommended adding sites sampled in consecutive seasons to better estimate local extinction and colonization rates"--Leaf iii