David James – “Butterfly Boom or Bust: The Ecology of Irruptions”
Some butterfly species show a peculiar ‘boom or bust’ population ecology. They are either present in large or overwhelming numbers or are extremely rare or absent. In the Pacific Northwest we have 6 or 7 species which show this characteristic (eg Painted lady, California Tortoiseshell, Pine white). The reasons behind this strange strategy or behavior have not been researched and are largely unknown for most species. However, we can develop reasonable hypotheses for the abundance or absence of some species and this talk will explore some of these in the Pacific Northwest.
Center for Urban Horticulture- 3501 NE 41st Street, Seattle, WA