Influence of rodent abundance on nesting success of prairie waterfowl

摘要: Most waterfowl nesting failure in the prairie biome is attributed to predation. However, contribution of small mammal abundance predator-prey cycle and how this affects productivity not known. We mod- elled seasonal variability success, including a number habitat nest-related variables, quantify influence rodent for six study sites Prairie Pothole Region Canada, 1996-1998. estimated there curvilinear relationship between meadow voles (Microtus pennsylvanicus (Ord, 1815)) success ducks. The has characteristics alternate prey hypothesis at low vole density shared higher densities. At densities, duck nests appear be buffered from predation by but, was affected negatively. recommend that dynamics should included as an integral part management plans suggest fur- ther research using rigorous experiment design elucidate mechanisms pathways responsible observed rela- tionship. Resume´ : On attribue la plupart des echecs de nidification oiseaux aquatiques dans le prairies ala preda- tion. Cependant, l'abondance petits mammiferes au predateurs-proies et son effet sur productivitedes restent inconnus. Nous modelisons variabilitesaisonniere du succesd e incluant plusieurs variables reliees al'habitat nid, afin mesurer l'influence rongeurs les pendant leur asix d'etude region cuv- ettes canadiennes, en estimons qu'il y une relation curviligne entre cam- pagnols Pennsylvanie succes chez canards. Cette possede, aux faibles densites campagnols, certains caracteres l'hypothese proies rechange et, den- plus elevees, caracteristiques partagees. Aux nids canards semblent etre preserves par mais, fortes, nidifica- tion est affectenegativement. recommandons que dynamique fasse partie integrante d'amenagement durant nous proposons recherches supplementaires avec un plan d'experience rigoureux pour elucider mecanismes voies responsables observons. (Traduit Redaction)