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18 2.1. Abstract Wildlife biologists are under increased pressure to handle animais safely. Through an intensive seven-year field study of a North American porcupine (Erethizon dorsatum) population, we devoted considerable efforts sem'ching, capturing, and handling large numbers of adult and juvenile individuals. Few published reports describe techniques adapted to this challenging species. We improved available techniques and developed new ones. We describe one method to sem'ch for juvenile porcupines, four new capture methods, one longlasting marking technique, and a customized radio collar minimizing wounds to animaIs. The method we used to sem'ch for juveniles allowed a success rate of 47.7% (21 juveniles found around 44 females). The most efficient capture method involved using a dip net and yielded 1,026 captures (out of 1,154 captures perfOlmed during the study). We marked animaIs using various types of ear tags, which allowed us to identify animaIs from a distance and in the long tenn. Only 8.5% ofmarked individuals (n = 14 out of 165 marked individuals) 10st their identity through tag loss, whereas only 3.5% of radiocollared porcupines (n = 6 out of 171 collars fitted) suffered from wounds directly attributable to radio collars. We suggest possible ways to further increase efficiency of our methods. Key-words : capture, dip net, juvenile, marking, porcupine, Québec, telemetry 2.2. Introduction Porcupines are present on four of the six continents, and can locally reach high densities (Roze 1989). A lthough they form two very distinct taxonomic groups (New World and O ld Word porcupines), they share the common feature of bearing quillS that impose significant challenges to anyone in need of manipulating them. lnterestingly, published infonnation on how to handle these animaIs is not abundant. We studied intensively a population of North American porcupines (Erethizon dorsatum) for se ven years in Canada and were confronted with the problem of handling porcupines. Here we first review published methods to search, capture and mark NOl1h American porcupines, we th en explain why some important
19 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
Page 1 and 2: UNIVERSITÉ DU QUÉBEC À RIMOUSKI
Page 3 and 4: Remerciements Cette thèse n'aurait
Page 5 and 6: Table des matières LISTE DES TABLE
Page 7 and 8: Liste des tableaux Chapitre 3 Table
Page 9 and 10: VB Table 4.2 Power consumed (in Wat
Page 11 and 12: Liste des figures Chapitre 1 Figure
Page 13 and 14: XI Figure 2.3 Number oftimes ajuven
Page 15 and 16: Xlll Figure 4.3 Time spent outside
Page 17 and 18: Liste des annexes Annexe 1 Descript
Page 19 and 20: Chapitre 1 Introduction 1.1 Impact
Page 21 and 22: 3 L ' importance relative des facte
Page 23 and 24: 5 des populations ne donne qu' une
Page 25 and 26: 7 (Tympanuchus pallidicinctus) les
Page 27 and 28: 9 1940 1000 1960 139---------- c ~
Page 29 and 30: 1 1 (Roze 1987). Ils perdent 10 à
Page 31 and 32: 13 140 a) 1 20 - o -l- 2000 2001 20
Page 33 and 34: 15 manipulations et la pose d'émet
Page 35: Chapitre 2 Handling North American
Page 39 and 40: 21 We searched for juvenile porcupi
Page 41 and 42: 23 Switzerland). To check sex and r
Page 43 and 44: 25 transmitters fo r larger units s
Page 45 and 46: 27 8 a) 7 "0 c: :l 0 6 -If) ~ c: 5
Page 47 and 48: 29 record sex, reproducti ve status
Page 49 and 50: Chapitre 3 Predation as a possible
Page 51 and 52: 33 3.2. Introduction A growing numb
Page 53 and 54: 35 predation risk. To do so, we tes
Page 55 and 56: 37 Table 3.1 : Monitoring effort ac
Page 57 and 58: 39 winter precipitation (total prec
Page 59 and 60: 41 emaciated), road kills, dead fro
Page 61 and 62: 43 Seasonal survival rates The sele
Page 63 and 64: 45 >. 1.0 0.9 ..... 0.8 .c ta .c 0.
Page 65 and 66: 47 Causes of mortality We assigned
Page 67 and 68: 49 100 - 90 a) 80 1/) c: .2 iii ...
Page 69 and 70: 51 too simplistic to detect complex
Page 71 and 72: 53 correlated with winter survival
Page 73 and 74: 55 4.1. A bstract Because the clima
Page 75 and 76: 57 Ta, first because of the effects
Page 77 and 78: 59 Third, we evaluated the behaviou
Page 79 and 80: 61 pattern of den use over one or t
Page 81 and 82: 63 two modali ties, Table 4.1, mode
Page 83 and 84: 65 feeding behaviour for the popula
Page 85 and 86: 67 of Tc we considered. However, we
Page 87 and 88:
69 Calculating TefrOIn Ta, wind spe
Page 89 and 90:
71 Number and duration of activity
Page 91 and 92:
73 8 o _ --L-_ 0 Operative temperat
Page 93 and 94:
75 Beschta 2004). Predation rates w
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77 in our population (chap. 3). Mal
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79 Tableau 4.5 : Pourcentage d'obse
Page 99 and 100:
81 associées avec le temps de surv
Page 101 and 102:
83 5.1. Abstract ln many mammals, j
Page 103 and 104:
85 use of coyer influenced summer s
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87 juvenile was moving to escape fr
Page 107 and 108:
89 individual (using approximations
Page 109 and 110:
91 den use (treated as a binary var
Page 111 and 112:
1 93 20 - 18 ~ a) DAvailable .Used
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95 80 -, 70 l DAvailable .Used 60 -
Page 115 and 116:
97 Table 5.3: Use of coyer by juven
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99 juveniles. At the microhabitat s
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101 However, we think protection fr
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103 we found that most mortalities
Page 123 and 124:
Chapitre 6 Conclusion Dans le cadre
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107 porcs-épics fréquentent les c
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109 épies, via un impact des condi
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II I Hiver E n hi ver, on montre qu
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113 compromis auquel les animaux fo
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11 5 En été, la mortalité des je
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117 pékan dans la région. On mont
Page 137 and 138:
119 Annexe 2 Étalonnage des modèl
Page 139 and 140:
121 Références Aanes, R. , & R. A
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Bult, A., & C. B. Lynch. 1997. Nest
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125 Creel, S. , 1. Winnie, B . Maxw
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127 Fortin, D., & G. Gauthier. 2000
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129 Hik, D. S. 1995. Does risk of p
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Lent, P. C. 1974. Mother-infant rel
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133 Murray, D. L. , & S. Boutin. 19
Page 153 and 154:
au Québec depuis 1984. Ministère
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137 Proceedings of the Royal Societ
Page 157 and 158:
139 Tsiropoula, G. 2003. Signatures
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