Relations among fishers, snow, and martens: Development and evaluation of two hypotheses

Abstract

Literature about the fisher (Martes pennanti) contains the folLes rtftrences faites au ptkan (Martes pennanti) soultvent lowing contradictions: (1) the species is an old-growth specialdeux contradictions: (1) l'esptce est un s#cialiste des vieilles ist versus a forest generalist, and (2) it lives with marten (M. a m rfor& par opposition B un g6ntraliste de toutes les forCts, et (2) il icana) with minimal interaction versus densities of the two vit avec un minimum d'interaction avec la martre (M. americana) species are inversely related. These contradictions beg the quespar rapport B la densit6 inversement relite des deux esptces. Ces contradictions posent les questions suivantes B savoir quel est tions of what is fisher habitat and does habitat affect the interactions l,habitat du ptkan et comment celui-ci affecte les interactions des the Martes. These questions were examinedb~ dew Martes. Ces questions ant kt6 6mdites en fonction de l'andyse the distributions of fishers (n = 15,549) and martens (n = 40,516) de la distributions des ptkans (n = 15 549) et des martres (n = 40 harvested in Maine, 1980Maine, -1987 fr6quentes (Xmensuel = 6.5) et un couvert neigeux abondant (X total were rare in northwestern Maine but were common throughout mensue1 2 48 cm) entre les mois de decembre et mars. Les p6kans the rest of the state where snowfalls were less freq~ent. We &lent rares dms le nord-ouest du Maine mais c o m u n s dans le hypothesize that regular accumulations of deep snow reduce reste de l'6tat oii les prkipitations de neige 6taient moins fr6quentes. the fisher's fitness (via decreasing recruitment, survival, or both), Nous posons comme hypothk que l'accumukdon r6gulik de neige resulting in a low abundance in northwestern Maine. In addition, r6duit l'extension de l'aire du ptkm (au niveau de sa reproduction, we hypothesize that mns are rare in southem ~~i~~ due to de sa survie ou de ces deux 616ments), ayant pour cons6quence un petition from a dense fisher population. nese hypotheses were faible niveau de population dans le nord-ouest du Maine. De plus, nous posons cornme hypothtse que la marire est peu abondante dans evaluated looking at patterns in age and recruitment ratios of le sud du Maine par suite de la comp&tition exercte la populafishers (n = 2,706) and martens (n = 5,572) harvested in core and tion plus 61evk de gh. ces hypothtses 6 e evduks par ~6 u d e noncore habitats for 1980-1984. We found low de la distributions des 8ges et des ratios de jeunes animaux chez les of fisher recruitment (P < 0.001) in the marten's core habitat conp6kans (n = 2 706) et les martres (n = 5 572) pitgts dans le habisistent with the hypothesis that deep and frequent snowfalls tats principaux et secondaires des deux exptces entre 1980 et limit fishers. Few adult martens were harvested (P < 0.001) in the 1984. Nous avons relevt des indices faibles de reproduction (P < core habitats of fisher, consistent with our hypothesis that high 0.001) au coeur de l'habitat de la martre ce qui est consistant avec fisher densities limit ...

Ecology and conservation of lynx in the United States

“…In carnivores, for example, Paquet (1991) reported that coyotes did not avoid wolves during winter, and Gese et al (1996) concluded that coyotes tolerated red foxes in Yellowstone National Park during a high prey year, but not at other times. A strong abiotic affect on interactions between another pair of forest-dwelling carnivores, the marten and fisher, has been described by Krohn et al (1995). Martens, with their proportionally larger feet, can travel in deeper, softer snow than can fishers, and martens predominate in parts of Maine with deep soft snow.…”

21st century Wisconsin snow projections based on an operational snow model driven by statistically downscaled climate data

“…The small ratio of body mass to foot area in the American marten and lynx provides this competitive advantage on snow (Krohn et al, 1995;Mowat et al, 2000;Carroll, 2007). American marten are well adapted to deep snowpacks, given their ability to tunnel into the snow to track small mammals and find warmth among tree roots.…”

REGIONAL VARIATION IN HOME‐RANGE‐SCALE HABITAT MODELS FOR FISHER (MARTES PENNANTI) IN CALIFORNIA

“…At the regional scale (1000-10 000 km 2 ), western fisher populations generally occur in mountainous areas with extensive forest cover and low-to-moderate snowfall , Powell and Zielinski 1994, Krohn et al 1995. In California, Powell and Zielinski (1994) estimated the minimum area needed to support a viable fisher population to be at least 600 km 2 .…”