Seasonal and spatial changes of sand fly species in a canyon in the Carmel Mountains

Altogether, 4,008 sand flies belonging to seven species were collected over a period of one year in the micro-habitats of a single canyon in the Carmel Mountain ridge. The three most abundant were P. arabicus, P. tobbi, and P. simici. Our results suggest that none of the seven sand fly species was indifferent to the heterogeneity of the microenvironment inside the canyon. Apart from the rare P. perfiliewi, which was only collected on the upper part of the south-facing slope, and P. tobbi, which clustered on the north-facing slope, the bulk of the other sand flies were caught on the bottom of the canyon. During the summer, the catches of all sand fly species increased to reach their maximum number in August and September. In April and May, there was lush vegetation and humidity, so species were distributed evenly throughout their habitats. With the onset of summer dryness, the sand flies concentrated in the humid habitats. The rate of concentration was essentially higher for males than for females, and this variation may result from differences in the behavior of the two sexes. During our study, none of the 2,318 dissected female sand flies were positive for Leishmania promastigotes.