PARENT SESSION
Poster Session #16: Fire Ecology.
Tuesday, August 7, 2001. Presentation from 3:30 PM to 5:00 PM. Exhibition Hall

Invertebrate population dynamics after oak community disturbance by burning in California, USA, and Portugal, South Europe.

Narog, Marcia¹, Nunes, Luisa², Wilson, Ruth³, ^{1 2 3}

ABSTRACT- Invertebrate population dynamics were examined before and after disturbance by prescribed burning in oak communities in California, USA, and Portugal, South Europe. Specimens were collected by using pitfall traps, brush beating and vacuuming; and were identified to species when possible. Abundance and diversity changes were compared within and between sites for both countries. The Class Insecta accounted for over 90 percent of the invertebrates collected and is the focus of this disturbance and community dynamics analysis. Fewer than 20 percent of the insect families identified accounted for more than 95 percent of the total number collected. Coleoptera, Collembola, Orthoptera, Hymenoptera, and Diptera, were the most abundant insect orders observed on the study sites. Coleoptera showed the greatest species diversity and Collembola had the highest number of individuals found. Generally, species abundance decreased more than diversity after the burns. Population recovery ranging from 1 month to 3 years after treatment suggests that the insect fauna in these oak communities are resilient to habitat disruption by fire. We recommend that further studies be conducted at additional sites and at greater post-burn intervals to ascertain if the observed insect population dynamics are typical for oak habitat recovery after fire disturbance.

KEY WORDS: invertebrates, fire, oak, disturbance