influence du climat et de la prédation sur l'utilisation de l'habitat et la ...

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information is lacking in the published literature, and we finally suggest four research
obj ecti ves that will structure the rest of the paper.
Porcupines usually live in forests where they are difficult to locate. Hale and Fuller
( 1999) report low success wh en walking along transects to search for porcupines. Sweitzer
and Berger (1997) worked in relatively open habitats and were successful at locating
porcupines using trained dogs and night-vision equipment. However, by far the most efficient
described technique to find porcupines involves snow tracking to locate dens where
porcupines concentrate their activity in winter (Stricklan et al. 1995, Zimmerling 2005).
Capture techniques include constraining porcupines in a garbage can (Craig & Keller
1986), climbing trees to catch individuals using heavy gloves (Roze 1989, Stricklan et al.
1995), placing cage-type live traps outside occupied dens, trees or on well-used paths (Hale
& Fuller 1996, Griesemer et al. 1999, lise & Hellgren 2001, Zimmerling & Craft 2001),
netting the animal before (Zimmerling & Croft 2001 , Zimmerling 2005) or after (lIse &
Hellgren 2001) chemical immobilization, and using heavy gloves after immobilizing animaIs
in trees or dens using a jabstick (Sweitzer & Berger 1992, Griesemer et al. 1999, lise &
Hellgren 2001) or a blow dart (Griesemer et al. 1999).
Marking techniques involve metal ear tags (Craig & Keller 1986, Zimmerling & Croft
2001) to which are sometimes attached colored plastic tags to allow identification at a
distance (Sweitzer & Berger 1992, Griesemer et al. 1999), spraying tail with enamel paint
(Sweitzer & Berger 1992), tattooing (Griesemer et al. 1999), fitting radio transmitter using
hm·ness and back pack (Craig & Keller 1986), or radiocollaring (e.g. Roze 1987, Sweitzer &
Berger 1992, Griesemer et al. 1999, lIse & Hellgren 2001). Flags have been attached to
antennas of radio collars to ease identification of individuals at a distance (Griesemer et al.
1999).
Published techniques to search for, capture, and mark porcupines represent a fraction of
those that have been tried by biologists, and method sections of publications usually do not
quantify efficiency of techniques. Griesemer et al. (1999) evaluate some methods to capture
and mark adult porcllpines. They do not deal with jllveniles, however, and some of their
reported methods needed improvement. Specifically, the method they used for mm"king did
not allow identification at a distance and was not long-lasting (25% of individuals had lost ail
tags 6-18 months after tagging). AIso, 7% of their radio collars created wOllnds (Griesemer et