COMPETITION BETWEEN NICROPHORUS ORBICOLLIS AND N. DEFODIENS: RESOURCE LOCATING EFFICIENCY AND TEMPORAL PARTITIONING

• Published in: Northeastern naturalist 2002, Vol.9 (1), p.13-26
• Main Authors: Trumbo, Stephen T, Bloch, Philip L
• Format: Article
• Language: English
• Subjects: Animal behavior; Beetles; Carrion; Congeners; Ecological competition; Entomology; Insects; Male animals; Natural resources; Photoperiod; Plant litter; s; State forests
• ISSN: 1092-6194; 1938-5307
• DOI: 10.1656/1092-6194(2002)009[0013:CBNOAN]2.0.CO;2

The larger-bodied burying beetle, Nicrophorus orbicollis, competes with the smaller N. defodiens for valued, protein-rich, carrion resources. We tested four hypotheses of this competitive relationship. We found support for the hypotheses that N. defodiens locates fresh carcasses more quickly than N. orbicollis and that carcasses placed under the leaf litter are more difficult for Nicrophorus to locate than carcasses placed above the leaf litter. By shifting the photocycle of N. defodienswe were able to manipulate this normally crepuscular species into beginning its active period 3 h later, during the active period of the nocturnal N. orbicollis. This clock-shift eliminates the 3 h head start that N. defodiens typically experiences in the field. We did not find support for the hypothesis that clock-shifted N. defodiens would suffer in competition compared to non-clock-shifted beetles. We did find support for the hypothesis that the presence of N. defodiens on a carcass provides clues to searching N. orbicollis. We suggest that the presence of efficient carrion searchers such as N. defodiens may significantly increase the numbers and success of the Nicrophorus guild.