Titre du document / Document title
Invader effects in a community of cavity nesting megachilid bees (Hymenoptera : Megachilidae)
Auteur(s) / Author(s)
BARTHELL J. F. (1) ;
FRANKIE G. W. (1) ;
THORP B. W. (2) ;
Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)
(1) Department of Environmental Science, Policy and Management, University of California, Berkeley, CA 94720, ETATS-UNIS
(2) Department of Entomology, University of California, Davis, CA 95616, ETATS-UNIS
Résumé / Abstract
Temporal and spatial characteristics of a community of cavity nesting megachilid bee species and their introduced competitors were examined at a site in the Central Valley of California. Two of the introduced bee species Megachile apicalis Spinola and Megachile rotundata (F.), were frequent nest site occupants and accounted for 19.6 and 3.4% of all artificial nesting cavities (trap-nests) monitored during the lst and 2nd yr of this study, respectively. These species were most active before and after the peak in native bee nesting activity and tended to occupy xeric habitats, despite significantly higher larval mortality associated with such environments. The ability to occupy a wide array of habitats may account for the invasion success of M. apicalis in California. Another invader, the European earwig, Forficula auricularia L., was a frequent occupant of nesting cavities in mesic habitats, accounting for 59 and 85% occupancy of trap-nests during the 1st and 2nd yr of the study, respectively. Exclusion experiments indicate earwig densities were sufficient to displace female bees at nest sites with 1/3 as much nesting activity occurrig in sampling units that allowed entry by earwigs as those made inaccessible to them with sticky barriers. In comparison all native species (including bees and wasps) never accounted for >25% of all occupied nesting cavities of either monitoring period of the study.
Revue / Journal Title
Environmental entomology
ISSN
0046-225X
CODEN EVETBX
Source / Source
1998, vol. 27, n
o2, pp. 240-247 (34 ref.)
Langue / Language
Anglais
Editeur / Publisher
Entomological Society of America, Lanham, MD, ETATS-UNIS
(1972)
(Revue)
Mots-clés anglais / English Keywords
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Mots-clés français / French Keywords
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Mots-clés espagnols / Spanish Keywords
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
Localisation / Location
INIST-CNRS, Cote INIST : 15465, 35400007584023.0090
Nº notice refdoc (ud4) : 2257317
