Demographics, movement, and resource use of the American Apollo butterfly Parnassius clodius (Papilionidae) in Grand Teton National Park, Wyoming, USA
Metapopulations are composed of multiple sub-populations, each connected by the infrequent exchange of individuals. These individuals maintain the genetic diversity of sub-populations, colonize vacant patches of suitable habitat, and recolonize subpopulations that go extinct. Therefore, movement of individuals through the landscape is the key to maintaining metapopulations. Understanding individual movement within a patch is the first step in understanding population dynamics at the landscape scale. The American Apollo (Parnassius clodius Menetries) (Lepidoptera: Papilionidae) exists in a mosaic of dry, sagebrush habitat patches surrounded by unsuitable forest habitat. The goal of this research was to estimate within-patch movement and resource use by P. clodius, in Grand Teton National Park, WY, USA. A plot-based mark-recapture approach was used during 3 consecutive summers (1998-2000) to estimate movement distances of individuals. The average straight-line movement per day was 200 meters. However, movement estimates in all 3 years were highly correlated with the average distance between the plots sampled. Proportional coverage of the species larval host plant, Dicentra uniflora (Fumariaceae), (1999) and abundance of the primary nectar species, Eriogonum umbellatum (Polygonaceae), (1999 and 2000) were estimated in each plot. Butterfly abundance was correlated with larval host plant coverage. There was a weak positive correlation between butterfly abundance and nectar abundance in 1999, but no relationship in 2000. The program Mark was used to analyze demographic data. Capture probability was significantly lower for females than for males across all 3 years, but there was no difference between sexes in survival rate. Survival and capture probability decreased over the course of each season, while movement transition probability between plots increased.