Seasonal Variation of Medfly Occurrences in the Continental United States

Abstract

Mediterranean fruit fly (Ceratitis capitata (Wiedemann)), or Medfly, has been detected 32 times in the continental United States since 1929. Eighteen of these represented infestations and USDA initiated eradication programs. In 14 other cases, 1 or 2 adult Medflies were captured. Trapping was intensified and because no other flies were captured it was determined no infestations existed (Table 1). The purpose of this paper is to evaluate the seasonal variation of Medfly detections in the continental United States and to examine possible factors affecting this variation. Factors include climate and host phenology at California and Florida locations (which could effect Medfly colonization potential in different seasons) and seasonal variations in movement of infested plant material from areas where Medfly occurs.