The stability of vertical distribution profiles of insects in air layers near the ground

Abstract

The vertical distribution of insect orders, families, and species captured over 10 elevations from the ground to 15 m over 4 years in a potato agro-ecosystem differed considerably within and between taxa. Regression slopes representing these aerial profiles remained similar over the 4 years of the study for orders Thysanoptera, Neuroptera, and Psocoptera, changed considerably for Hemiptera, Homoptera and Ephemeroptera, and were statistically non-homogeneous for Coleoptera, Hymenoptera, Diptera, Lepidoptera, Trichoptera, and Plecoptera. The slopes of the aerial profiles for families remained similar over the years for Carabidae and Elateridae, changed for Staphylinidae, Meloidae, and Scarabeidae, but were statistically non-homogeneous for Coccinellidae, Miridae, and Aphididae. The slopes of the aerial profiles for insect species were similar across years for Coccinella septempunctata L., Melanotus similis (Kirby), and Anatis mali Say, changed for Pyrrhalta luteola (Mull.), Ctenicera pulchra LeConte, Ctenicera tarsalis Melsheimer, Coccinella trifasciata perplexa Muls., Lygus lineolaris (P. de B.), Ctenicera appropinquans Randall, Apis mellifera L., and Adalia bipunctata (L.), but were significantly non-homogeneous only for Hippodamia convergens G.-M. Although most profiles obtained for insect orders in this study were remarkably similar to those reported in the literature, the level of between-year variation at our study site suggests that there is considerable overlap between profiles at all taxon levels. Vertical aerial profiles cannot be considered sufficiently characteristic of the species, family, or order across years for use as indicators of change in biodiversity. The impact of these results on insect monitoring are discussed.

Vertical distribution profile of Colorado potato beetle [Coleoptera: Chrysomelidae] in flight above host, resistant host and non-host fields

“…A preliminary study described a strong, steep and negative vertical flight profile for the CPB above a potato crop, with 50% of the flights over the first 15 m above ground occurring at or below 2.3 m (Boiteau et al 2000b). Our study using a larger number of flight records and a different style of flight interception trap, confirms the sharp drop in flight frequency at higher elevations (2.4 -3.6 m).…”

“…The horizontal dispersal by flight of CPB into, within and between potato fields and other hosts is becoming better understood (Boiteau 1986;Follet et al 1996;French et al 1993;Hoy et al 1996;Noronha and Cloutier 1999;Voss andFerro 1990a, 1990b;Weber andFerro 1993, 1994;Weber et al 1994Weber et al , 1995Weisz et al 1994;Williams 1988;Zehnder and Speese 1987) but information on the vertical profile for CPB remains preliminary (Boiteau et al 2000b). …”

“…Few studies (Boiteau et al 1999(Boiteau et al , 2000a(Boiteau et al , 2000b have evaluated insect vertical profiles above agricultural landscapes and the most exhaustive study on vertical distributions of insect populations in flight (Taylor 1974) was carried out above grass. The objective of this project was to determine if the vertical distribution profile of CPB in flight above the potato crop changed as beetles dispersed above CPB resistant crops and non-host crops.…”

The Colorado potato beetle in movement

“…Windowpane and pitfall traps Zehnder and Speese (1987); Boiteau (2001); Voss andFerro (1990a, 1990b); Noronha and Cloutier (1999); Boiteau et al (1994); Boiteau et al (2000) Inferring beetle movement from changes in beetle density Increase or decrease in adult density, usually determined by visual counts, is presumed to be a result of their immigration or emigration ; Wright (1984); Horton and Capinera (1990); Hoy et al (1996); Weisz et al (1994Weisz et al ( , 1996 Mark-release-recapture Marking options tested so far include enamel paints, felt tip pens, radioactive rubidium fluoride, paper labels glued to elytra, elytral punctures, and electronic tags that allow tracking beetles by a harmonic radar system Wegorek et al (1967); Bach (1982); Boiteau (1986); Jermy et al (1988); Williams (1988); Hare (1983); Voss and Ferro (1985); ; Unruh and Chauvin (1993), Colpitts et al (1999) 1.4 cm/s in the young adult to 0.72 cm/s in the mature adult (Jermy et al 1988), from 1.8 cm/s on the horizontal to 0.3 cm/s on a 90°slope (Pelletier and Caissie 2001), and is inversely proportional to the soil temperature within a range of 24-40°C (Jermy et al 1988). The leg muscles become exhausted over a few hours and the walking speed slows down to a stop (Grison 1957).…”

Responses of Syrphids, Elaterids and Bees to Single-tree Selection Harvesting in Algonquin Provincial Park, Ontario

“…Elaterids were most abundant in the old logged habitats, using two methods of sampling, indicating positive responses to the much higher cover of the sapling (2-10 m) layers found in this treatment (Jobes et al 2004). The most abundant species, Selatosomus pulcher, has been trapped in open field habitats (Boiteau et al 2000). This species is morphologically nearly indistinguishable from the European species C. cruciatus, a species whose larvae develop in the sandy and moist soils in forest and forest edge (Leseigneur 1972).…”