sign in sign up
<<
Home , Canada lynx

Lucretia E. Olson1, John R. Squires, U.S. Forest Service, Rocky Mountain Research Station, 800 E. Beckwith, Missoula, 59801, Nicholas J. DeCesare, College of Forestry and Conservation, University of Montana, Missoula, Montana 59812, and Jay A. Kolbe, Montana Fish, Wildlife and Parks, P.O. Box 1288, Seeley Lake, Montana 59868

Den Use and Activity Patterns in Female (Lynx canadensis) in the Northern

Abstract Knowledge of female behavior while rearing young can have important implications for species conservation. We located dens and analyzed activity (defined as movement between consecutive GPS locations) for nine female lynx with kittens in the north- central Rocky Mountains in 2005 and 2007. We used GPS tracking collars to quantify the percentage of time a female spent active and her daily distance traveled for each of three reproductive stages, classified as predenning, denning, and postdenning. We also described the use and placement of maternal dens for these females. Female lynx in our study used one to six dens per breeding season, and increased both frequency of den relocation and distance between dens as kittens matured. Females typically left the den twice a day, and were gone for an average of five hours at a time. Females were active for 56% of a given 24 hour period during predenning, 48% during denning, and 61% during postdenning. Females traveled greater distances in 24 hours during predenning than denning. We conclude that reproductive female lynx alter the amount of time they spend active and daily distance traveled based on reproductive status.

Introduction al. 2000, Organ et al. 2008, Squires et al. 2008). In Montana, lynx predominantly den in complex Understanding a species’ reproductive behavior is mature forest stands with high horizontal cover often critical for successful conservation planning. (Squires et al. 2008). Lynx give birth in a natal The extent and type of habitat needed by female den and often move kittens to one or more sub- for successful reproduction can differ sequent dens, known as maternal dens (Slough from that needed by a species in general (Morris 1999, Squires et al. 2008). Detailed information 1984, Chamberlain et al. 2002). may also on the timing and duration of Canada lynx natal be especially sensitive to anthropogenic disturbance and maternal den use is currently lacking from when they are breeding or rearing young (Weaver the literature. et al. 1996). Thus, it is important to understand Maternal behavior and den use may also im- the timing and duration of reproductive activities pact female lynx activity and movement pat- so that appropriate conservation actions can be terns. Female mammals undergo large changes implemented. in daily energy requirements depending on their Canada lynx (Lynx canadensis) are a federally reproductive stage (Gittleman and Thompson threatened species in the United States (U.S. Fish 1988). Reproductive females have higher energy and Wildlife Service 2000) and yet much remains demands during the early rearing period due to unknown concerning their maternal and denning gestation, lactation, and an increased hunting behavior. Previous work on denning in the Canada effort necessary to feed offspring (Oftedal 1984, lynx has focused on den site selection or habitat Gittleman and Thompson 1988). In species with requirements (Koehler 1990, Slough 1999, Moen altricial young, the need to protect young from 2008, Squires et al. 2008). Lynx establish dens predators, aid in thermoregulation, and carry in young to mature forest with dense cover and young can also increase a female’s energy needs large amounts of coarse woody debris (Mowat et (Altman and Samuels 1992, Laurenson 1994, Walton and Wynne-Edwards 1997). The extent to which female lynx adjust their movements and 1Author to whom correspondence should be addressed. activity patterns to account for the increased cost Email: [email protected] of supporting young kittens is unclear.

Northwest Science, Vol. 85, No. 3, 2011 455 Methods Study areas were located in the Purcell Mountains of northwest Montana near the Canada and borders (115o W, 48o N) and near Seeley Lake, Montana (113o W, 47 o N), approximately 200 km to the southeast. In May and June 2005 and 2007, we used radio-telemetry to locate nine active dens from previously marked Canada lynx females and GPS to determine the activity patterns of these nine females. We used radio-telemetry to locate 50 other dens from these nine and 16 additional female lynx from 1999 to 2009 to characterize the timing of partu- rition in western Montana. Females were captured and collared as part of a larger research effort. Trapping, handling, and Figure 1. Two- to three-week-old Canada lynx kittens in a maternal den in den location methods followed Squires the northern Rocky Mountains (photo by Zachary Wallace). et al. (2008) and an Institutional Care and Use Committee permit (# 4-2008). Lynx were collared with GPS Canada lynx produce litters of three to four radio-collars (Sirtrack Ltd, Havelock North, New semi-altricial kittens once a year (Brand and Keith Zealand) also equipped with VHF-transmitters to 1979, Aubry et al. 2000) (Figure 1). Kittens of most enable location on the ground. Collars were pro- Lynx species are weaned at 12 weeks (McCord and grammed to record a location every 30 minutes for Cardoza 1982), but may eat meat at four weeks 24 hours, every other day. Females in 2005 were (Tumlison 1987). (Lynx lynx) begin re-located in December 2005 or January 2006 and walking at 24 to 30 days (Tumlison 1987), and from snow-tracks were determined to have at least (Lynx pardinus) are mobile enough one surviving kitten. Females in 2007 were not to leave the den at around two months (Fernández relocated due to funding constraints; therefore we et al. 2002). Canada lynx kittens remain with assumed that kitten survival was similar to 2005. their mothers until they are approximately 9–10 We used GPS data and ArcMap (ArcGIS 9.2, months old (Parker et al. 1983, Koehler 1990), ESRI, Redlands, CA) to confirm dens located on after which time most kittens disperse (Mowat the ground and to determine subsequent maternal et al. 1996, Poole 1997). den locations. Lynx were considered to have Here we investigate den use and seasonal and localized at a natal (parturient) den when their diel activity patterns of female Canada lynx with GPS positions were first clustered within a 100 kittens in the north-central Rocky Mountains of m radius of one location for longer than 24 hours Montana. We describe natal and maternal den use (Koehler 1990, Moen et al. 2008). We quantified and date of parturition for lynx in this population. the number of subsequent maternal dens a female We also describe how activity patterns (includ- used by counting additional distinct locations ing percentage of time spent active and daily where female telemetry relocation points were distance traveled) differ as kittens mature. We clustered for longer than 24 hrs. We used ArcMap test the prediction that females will increase the to determine the distance between consecutive proportion of time spent away from the den and dens and the number of days spent in each den. distance traveled from the den as kittens mature, We also determined the age of kittens (in days) since newly born kittens are semi-altricial and when each den relocation occurred. We then used require more parental care, and older kittens may mixed effects regression to test whether the length have greater energetic requirements, necessitating of time a den was used and the distance between more foraging effort. consecutive dens was correlated with kitten age.

456 Olson et al. Analysis was conducted with StataIC version of segments in a 24 hr GPS track. To control for 10.1 (StataCorp 2007, College Station, TX) with changing hours of daylight during each season we distance or days per den as the dependent variable, determined the times of sunrise and sunset on the kitten age as a fixed effect, and individual female 15th day of each month and classified each hour in as a random effect. We estimated the date that a month into 4 time of day categories: dawn (1 hr localized denning ended for each female as the before and after sunrise), day, dusk (1 hr before last date that females repeatedly visited any one and after sunset), and night. We examined the total location for > 48 hrs. During the time that females minimum distance females traveled while active were localized at a den, we also quantified mean (sum of all active 30 min segments) during a 24 number of times females left dens per 24 hr period hr period as well as the net displacement distance and duration of consecutive time spent away from (straight line distance from start to end of a GPS dens in 24 hrs. To qualify as away from the den, track) from 0600 hr to 0600 hr of the next day for females had to be > 100 m from the den for at each of the three reproductive seasons. least two consecutive GPS locations. We used SAS, version 9.2, (SAS Institute, To examine female activity patterns at different Cary, NC) to estimate a generalized linear mixed stages of reproduction, we divided GPS movement model (GLMM) of percentage of time spent ac- data into three seasons: predenning (February - tive, with individual females and GPS track date April, females breeding/pregnant), denning (May- as random factors to control for a potential lack of July, parturition/lactation, non-mobile kittens), independence within lynx tracks. We considered and postdenning (August - October, provisioning, season and time of day fixed factors and used the kittens able to travel). We categorized lynx behav- containment method to determine denominator ior at each GPS location into ‘active’ or ‘resting’ degrees of freedom (West et al. 2007). We used states using step length and turn angle data from a logistic GLMM to analyze percentage of time movement paths (Johnson et al. 2002, Morales et spent active since the outcome variable was binary al. 2004). ‘Active’ locations occurred when lynx (active or resting; Hosmer and Lemeshow 2000). were moving, whereas ‘resting’ locations occurred We conducted pair-wise comparisons in the GLMM when lynx were stationary. To distinguish true using the difference in least square means (DLSM) movement from that induced by GPS error, we between all levels of each factor (season, time compared the step length and turn angles leading of day, and season by time of day interaction), to each GPS location to the distribution of step and adjusted for multiple comparisons using the lengths and turn angles from test collars known Tukey-Kramer adjustment. We compared total to be in a stationary position. Segments that had distance traveled and net displacement distance a length or turn-angle within the 70th percentile for each season using repeated measures ANOVA, of the stationary test collar’s segment distribution with distance as the dependent variable, season as were classified initially as ‘resting’; the remaining the independent variable, and individual lynx as a segments were classified as ‘active’. Among the random factor. Post-hoc comparisons to estimate remaining ‘active’ segments, we removed GPS differences between seasons were performed us- points which spiked abruptly away from clusters of ing a Tukey-Kramer pairwise comparison, with consecutive ‘resting’ points. Finally, to account for differences considered significant if P < 0.05. the autocorrelation in animal behavior monitored Summary statistics were first calculated within with systematic telemetry (Forester et al. 2007, a given female’s GPS track data and then aver- Gurarie et al. 2009) we also reclassified ‘active’ aged across all females to control for sampling points as ‘resting’ when an individual point was variation among females. All averages are means between 2 ‘resting’ points, each within 123 m (the ± standard deviations. 95th percentile of consecutive distances between known stationary locations). Results We analyzed differences in the percentage of In 2005, movement data were collected from time females spent active for each season (pre- February to October on four females, each for vary- denning, denning, postdenning) and time of day ing amounts of time. GPS data were measured in (dawn, day, dusk, night). Percentage of time spent lynx-days (one day of GPS tracking for one lynx); active was determined by the number of active 30 108 lynx-days were recorded for ‘predenning’ minute track segments divided by the total number (February–April), 152 for ‘denning’ (May–July),

Female Canada Lynx Activity and Den Use 457 and 23 for ‘postdenning’ (August–October). In 2007, data were collected on five different females from February to July. The predenning period had 170 lynx-days recorded and denning had 223 lynx-days. Each female was tracked for an average of 75.5 ± 7.7 days (range: 62–84 days). Lynx gave birth from 26 April to 23 May (me- dian date: 9 May, n = 59), except for one adult female who gave birth on 11 July, based on GPS data and field-estimated kitten age. Female den use ended from 22 June to 31 July (excluding the July birth). Thus the average length of localized den use was 59 ± 5 days (range = 50–66 days, n = 8). While females were localized at a den, Figure 2. The number of days each lynx remained in a given they left the den (> 100 m) an average of 2 ± 0.2 den, from natal den (Den number 1) to final mater- times per 24 hour period (range = 1–4, n = 9). An nal den (Den number 6). All dens for all nine lynx average bout away from the den lasted 5 ± 1 hrs (identified here as F1–F9) studied in 2005 and 2007 (range = 1–21 hrs, n = 9). in the northern Rocky Mountains are shown. Females used an average of 3 ± 2 maternal average of 56 ± 3% of a given 24 hr period active dens in a given year (range = 1–5, n = 9 females). during predenning, 48 ± 8% active while denning, The time spent in subsequent dens decreased with and 61 ± 5% active during postdenning. The sample time since parturition (mixed-effects regression: size of GPS tracks collected during postdenning B= -0.32, std. err. = 0.07, z = -4.69, P < 0.001). 9, 37 was markedly smaller than in either of the other Lynx stayed in natal dens for an average 21 ± 17 two seasons, so the lack of a difference between days (range = 8–52 days, n = 9), 14 ± 10.4 days postdenning and denning may have been due to n in the first maternal den (range = 2–32 days, = lack of statistical power. Across seasons, females 8), 5 ± 2.8 days in the second maternal den (range spent slightly more time active during dawn than = 2–10 days, n = 7), 11 ± 8.9 days in the third day or night (DLSM: day: t = 3.42, P = 0.006, maternal den (range = 2–22 days, n = 6), 4 ± 0.8 night: t = 2.71, P = 0.041), and during dusk than days in the fourth den (range = 2–4 days, n = 5), day or night (DLSM: day: t = 3.41, P = 0.006, and 4 ± 2 days in the fifth den (range = 2–6, n = night: t = 2.69, P = 0.043). Females spent 56 ± 2) (Figure 2). The average distance between con- 10% of their time active at dawn, 54 ± 9% at dusk, secutive den locations for all females was 786 ± 50 ± 6% at night, and 50 ± 7% during the day. 156.3 m (range = 133–1553 m, n = 9). The distance between consecutive dens increased with kitten age (mixed-effects regression: B = 17.17, std. err.

= 6.55, z9, 29 = 2.62, P = 0.01). The distance from natal den to first maternal den averaged 709 ± 532.2 m (range = 133–1479 m, n = 9), second to third den was 568 ± 396.6 m (range = 93–1288 m, n = 7), third to fourth was 543 ± 357.6 m (range = 210–1058 m, n = 6), fourth to fifth was 1539 ± 1121.9 m (range = 216–3057 m, n = 5), and fifth to sixth was 797 ± 53.0 m (range = 759–834, n = 2). Time spent active by females with kittens was influenced by both season and time of day (season:

F2, 15 = 5.86, P = 0.013; time of day: F3, 68 = 6.85, P < 0.001), as well as their interaction (F6, 68 = 17.31, P < 0.001) (Figure 3). Time spent active was Figure 3. Average percent of time spent active interaction plot for Canada lynx (plotted by time of day) as related greater during predenning than denning (DLSM: to season (predenning, denning, or postdenning), t = -3.26, P = 0.013; Figure 3). Females spent an in the northern Rocky Mountains, 2005 and 2007.

458 Olson et al. Time spent active was more variable throughout (1963) found that captive lynx kittens bury their a 24 hr day during postdenning and predenning feces. Adult lynx also do not generally leave prey than during denning (Figure 3). uneaten at the den, instead consuming between Female lynx traveled a greater minimum dis- 78% and 95% of hare carcasses (O’Donoghue et tance per 24 hr period during predenning (7.0 ± al. 1998). Females may also relocate dens because 3.2 km, n = 278) than during denning (6.3 ± 3.8 of den disturbance (Fernández et al. 2002). We km, n = 375; F = 4.04, P = 0.02). There was approached eight females’ dens on foot in this 2, 8 study; of these, four females relocated dens within no difference in the distance that females traveled four days, according to GPS data. The other four between predenning and postdenning (6.0 ± 2.6 females, however, did not relocate dens for at least km, n = 24) or denning and postdenning. There 20 days after the disturbance. Lynx in our study was also an effect of season on net displacement were also in remote areas unlikely to be acciden- (F = 41.14, P = 0.001). After kittens were born, 2, 8 tally approached by humans, so subsequent den females had shorter net displacement distances relocations were not likely due to human distur- (denning: 2.1 ± 1.2 km, n = 375; postdenning: bance. Thus, while it appears that some lynx may 1.9 ± 0.98 km, n = 24) than before kittens were relocate dens in response to human interaction, born (predenning: 2.9 ± 1.3 km, n = 278). There this is not the primary factor. Den relocation may was no difference in net displacement distance also occur to gain access to areas with increased between denning and postdenning. prey availability (Laurenson 1993), and as kittens mature, their increased ability to keep up with Discussion their mother may facilitate den relocation for this Canada lynx in the northern Rocky Mountains purpose (Kitchings and Story 1984, Fernández et al. 2002). Our data support this hypothesis, as relocated their kittens to as many as five maternal duration of time spent at maternal dens decreased dens per year. For most Lynx species, maternal as kittens grew and required more food, while the dens are little more than temporary sheltered loca- distance between dens increased as kittens became tions, which offer protection to the kittens from more able to travel. A similar pattern of juvenile extreme temperatures, precipitation, or predators relocation occurs in wolves ( lupus), with (Fernández and Palomares 2000, Boutros et al. pups kept in a natal den until they become more 2007, Moen et al. 2008). Relocating kittens to a mobile, at which point they are moved to one series of maternal dens from the natal den occurs or a series of rendezvous sites while adults hunt in all Lynx species (Iberian lynx, Fernández et al. (Ballard and Dau 1983, Fuller 1989). 2002; Canada lynx, Moen et al. 2008; , Lynx Female lynx traveled shorter daily distances rufus, Kitchings and Story 1984; and Eurasian lynx, and had smaller net displacement distances when Schmidt 1998). Similar numbers of maternal dens kittens were newborn to two months old than be- are used by Iberian and Eurasian lynx (5–6 and fore kittens were born. While kittens have limited 1–4 dens per year, respectively; Schmidt 1998, mobility, females appear to act as central-place Fernández et al. 2002). Females appeared to stop foragers (Orians and Pearson 1979) that return to caching kittens at dens for extended periods of time the den to accommodate the restricted movements when kittens were approximately two months old. of young kittens. When females are not limited At two months of age, kittens are still nursing (Mc- by the mobility of their offspring, however, they Cord and Cardoza 1982), but are also eating solid tend to cover greater daily distances. A reduction food and are mobile enough to travel with their in movement for females with young kittens has mothers (Tumlison 1987, Fernández et al. 2002). been found in other populations of lynx. For Female mammals may relocate dens to reduce example, female lynx in limit their the accumulation of excrement or parasites at dens daily foraging movements during the 50 days after (Butler and Roper 1996, Larivière and Messier parturition (Moen et al. 2008), with home ranges 1998), as well as prey remains that may attract during summer and fall 1.5 times bigger than dur- predators (Prestrud 1992). We used trained scat ing denning, and winter home ranges 3.6 times at several dens and did not locate any scat from bigger than during the denning season (Burdett et adults or kittens around the immediate den area al. 2007). Although females in our study restricted (J. Squires, personal observation), while Saunders their movements during early denning, they still

Female Canada Lynx Activity and Den Use 459 left their kittens approximately twice per day for (Elliott and Flinders 1991), on several occasions an average of five hours per day. (J. Squires, personal observation). Ground squir- The percentage of time females spent active rels may provide an important alternate prey for before kittens were born was greater than while females in the northern Rockies when denning; kittens were restricted to a den site. While denning, on several occasions we located dens in close females may decrease their activity to be present proximity to ground squirrel colonies (J. Squires, at dens for thermoregulation and protection from personal observation). predators. When kittens are older, females may Canada lynx in the northern Rocky Mountains increase their time spent active, and likely their give birth in late April to mid-May, with an average time spent foraging, to meet the increased caloric parturition date of 9 May, and thus are potentially demands of kittens as they mature. The increased restricted to dens from late April to late July. While mobility of offspring by two or three months of we did not formally evaluate disturbance to lynx age (Tumlison 1987) may also influence female in this study, our data and that of others suggests activity. Canada lynx, as well as other lynx species, may During predenning and postdenning, when respond to anthropogenic disturbance while den- kittens were either absent or less dependent, fe- ning by relocating kittens to a new den (Mowat males were more active during dusk or dawn and et al. 1996, Fernández et al. 2002). The impact of less active during the day, similar to Kolbe and den relocation on kitten survival in Canada lynx Squires (2007) finding on adult males and females is unknown, although the continued presence of without kittens. The primary prey species of lynx, kittens at first snow for all females whose dens the hare (Lepus americanus; Aubry et were approached in 2005 suggests that survival al. 2000), is crepuscular or nocturnal (Foresman may not be greatly affected. Nevertheless, if and Pearson 1999); thus we would expect lynx to managers are concerned with limiting potential forage more at night, or during dusk and dawn. disturbance to denning lynx in the northern Rocky While denning, however, females exhibited ap- Mountains, the most effective period will be from proximately equal levels of activity from dawn to late April to late July. dusk, with a slight drop in activity at night. The Acknowledgments roughly continuous diel activity of females while denning may be due to an adjustment in hunting We thank John Laundré, Ron Moen, David Turner, patterns to accommodate the needs of kittens for and an anonymous reviewer for helpful comments thermoregulation and protection from predators. on previous versions of the manuscript. Research There is evidence from other studies that lynx was funded by the Rocky Mountain Research Sta- adjust their prey seasonally, with a decrease in tion, Forestry Sciences Laboratory, Missoula, MT, dependence on hares in the summer, although the in cooperation with Region 1, U. S. Forest Service reasons for this adjustment are not well under- and the Bureau of Land Management. Logistical stood (Mowat et al. 2000). We observed denning support was provided by the Seeley Lake District, females hunting Columbian ground squirrels Lolo National Forest and the Rexford District, (Spermophilus columbianus), which are diurnal Kootenai National Forest. Literature Cited Boutros, D., C. Breitenmoser-Würsten, F. Zimmermann, A. Altmann, J., and A. Samuels. 1992. Costs of maternal care: Ryser, A. Molinari-Jobin, S. Capt, M. Güntert, and infant-carrying in baboons. Behavioral Ecology and U. Breitenmoser. 2007. Characterisation of Eurasian Sociobiology 29:391-398. lynx Lynx lynx den sites and kitten survival. Wildlife Aubry, K. B., G. M. Koehler, and J. R. Squires. 2000. Ecol- Biology 13:417-429. ogy of Canada lynx in southern boreal forests. In L. Brand, C. J., and C. B. Keith. 1979. Lynx demography during F. Ruggiero, K. B. Aubry, S. W. Buskirk, G. Koehler, a decline in Alberta. Journal of Wildlife C. J. Krebs, K. S. McKelvey, and J. R. Squires Management 43:827-849. (editors), Ecology and Conservation of Lynx in the Burdett, C. L., R. A. Moen, G. J. Niemi, and L. D. Mech. United States, University of Press, Boulder. 2007. Defining space use and movements of Canada Pp. 373-396. lynx with global positioning system telemetry. Journal Ballard, W. B., and J. R. Dau. 1983. Characteristics of gray of Mammalogy 88:457-467. wolf, Canis lupus, den and rendezvous sites in south- Butler, J. M., and T. J. Roper. 1996. Ectoparasites and sett use central . Canadian Field-Naturalist 97:299-302. in European . Animal Behaviour 52:621-629.

460 Olson et al. Chamberlain, M. J., L. M. Conner, and B. D. Leopold. 2002. Moen, R., C. L. Burdett, and G. J. Niemi. 2008. Movement Seasonal habitat selection by raccoons ( lotor) and habitat use of Canada lynx during denning in Min- in intensively managed pine forests of central Mis- nesota. Journal of Wildlife Management 72:1507-1513. sissippi. American Midland Naturalist 147:102-108. Morales, J. M., D. T. Haydon, J. Frair, K. E. Holsinger, and Elliott, C. L., and J. T. Flinders. 1991. Spermophilus colum- J. M. Fryxell. 2004. Extracting more out of reloca- bianus. Mammalian Species 372:1-9. tion data: Building movement models as mixtures of Fernández, N., and F. Palomares. 2000. The selection of random walks. Ecology 85:2436-2445. breeding dens by the endangered Iberian lynx (Lynx Morris, D. W. 1984. Sexual differences in habitat use by pardinus): implications for its conservation. Biological small mammals: evolutionary strategy or reproductive Conservation 94:51-61. constraint? Oecologia 65:51-57. Fernández, N., F. Palomares, and M. Delibes. 2002. The use Mowat, G., K. G. Poole, and M. O’Donoghue. 2000. Ecol- of breeding dens and kitten development in the Iberian ogy of lynx in northern Canada and Alaska. In L. F. lynx (Lynx pardinus). Journal of Zoology 258:1-5. Ruggiero, K. B. Aubry, S. W. Buskirk, G. Koehler, Foresman, K. R., and D. E. Pearson. 1999. Activity patterns C. J. Krebs, K. S. McKelvey, and J. R. Squires (edi- of American , Martes americana, snowshoe tors), Ecology and conservation of lynx in the United hares, Lepus americanus, and red squirrels, Tamias- States, University Press of Colorado, Boulder, CO. ciurus hudsonicus, in westcentral Montana. Canadian Pp. 265-306. Field-Naturalist 113:386-389. Mowat, G., B. G. Slough, and S. Boutin. 1996. Lynx re- Forester, J. D., A. R. Ives, M. G. Turner, D. P. Anderson, D. cruitment during a snowshoe hare population peak Fortin, H. L. Beyer, D. W. Smith, and M. S. Boyce. and decline in southwest . Journal of Wildlife 2007. State-space models link elk movement patterns Management 60:441-452. to landscape characteristics in Yellowstone national O’Donoghue, M., S. Boutin, C. J. Krebs, G. Zuleta, D. L. park. Ecological Monographs 77:285-299. Murray, and E. J. Hofer. 1998. Functional responses Fuller, T. K. 1989. Denning behavior of wolves in north-central of and lynx to the snowshoe hare cycle. Ecol- Minnesota. American Midland Naturalist 121:184-188. ogy 79:1193-1208. Gittleman, J. L., and S. D. Thompson. 1988. Energy allocation Oftedal, O. T. 1984. Milk composition, milk yield and energy in mammalian reproduction. Integrative and Compara- output at peak lactation: a comparative review. Sym- tive Biology 28:863-875. posia of the Zoological Society of London 51:33-85. Gurarie, E., R. D. Andrews, and K. L. Laidre. 2009. A novel Organ, J. F., J. H. Vashon, J. E. McDonald Jr, A. D. Vashon, method for identifying behavioral changes in animal movement data. Ecology Letters 12:395-408. S. M. Crowley, W. J. Jakubas, G. J. Matula Jr, and A. Hosmer, D. W., and S. Lemeshow. 2000. Applied Logistic L. Meehan. 2008. Within-stand selection of Canada Regression. Wiley-Interscience, Hoboken, NJ. lynx natal dens in northwest , USA. Journal of Johnson, C. J., K. L. Parker, D. C. Heard, and M. P. Gilling- Wildlife Management 72:1514-1517. ham. 2002. Movement parameters of and Orians, G. H., and N. E. Pearson. 1979. On the theory of scale-specific responses to the environment. Journal central place foraging. In D. J. Horn, R. Mitchell and of Animal Ecology 71:225-235. G. R. Stair (editors), Analysis of Ecological Systems, Kitchings, J. T., and J. D. Story. 1984. Movements and disper- Ohio State University Press, Columbus. Pp. 155-177. sal of in east Tennessee. Journal of Wildlife Parker, G. R., J. W. Maxwell, L. D. Morton, and G. E. J. Smith. Management 48:957-961. 1983. The ecology of the lynx (Lynx canadensis) on Koehler, G. M. 1990. Population and habitat characteristics of Cape Breton Island. Canadian Journal of Zoology lynx and snowshoe hares in north central . 61:770-786. Canadian Journal of Zoology 68:845-851. Poole, K. G. 1997. Dispersal patterns of lynx in the North- Kolbe, J. A., and J. R. Squires. 2007. Circadian activity pat- west Territories. Journal of Wildlife Management terns of Canada lynx in western Montana. Journal of 61:497-505. Wildlife Management 71:1607-1611. Prestrud, P. 1992. Denning and home-range characteristics of Larivière, S., and F. Messier. 1998. Denning ecology of the breeding arctic in Svalbard. Canadian Journal striped in the Canadian prairies: Implications of Zoology 70:1276-1283. for waterfowl nest predation. Journal of Applied Ecol- Saunders Jr, J. K. 1963. Movements and activities of the lynx ogy 35:207-213. in Newfoundland. Journal of Wildlife Management Laurenson, M. K. 1994. High juvenile mortality in 27:390-400. ( jubatus) and its consequences for maternal Schmidt, K. 1998. Maternal behaviour and juvenile dispersal care. Journal of Zoology 234:387-408. in the Eurasian lynx. Acta Theriologica 43:391-408. Laurenson, M. K. 1993. Early maternal behavior of wild Slough, B. G. 1999. Characteristics of Canada lynx, Lynx ca- cheetahs: Implications for captive husbandry. Zoo nadensis, maternal dens and denning habitat. Canadian Biology 12:31-43. Field-Naturalist 113:605-608. McCord, C. M., and J. E. Cardoza. 1982. Bobcat and lynx. In Squires, J. R., N. J. DeCesare, J. A. Kolbe, and L. F. Ruggiero. J. A. Chapman and G. A. Feldhamer (editors), Wild 2008. Hierarchical den selection of Canada lynx in Mammals of North America, The Johns Hopkins western Montana. Journal of Wildlife Management University Press, Baltimore, MD. Pp. 728-766. 72:1497-1506.

Female Canada Lynx Activity and Den Use 461 Tumlison, R. 1987. lynx. Mammalian Species 269:1-8. hamsters (Phodopus campbelli). Physiology and Be- United States Fish and Wildlife Service. 2000. Endangered haviour 63:41-47. and threatened wildlife and plants; determination Weaver, J. L., P. C. Paquet, and L. F. Ruggiero. 1996. Re- of threatened status for the contiguous U.S. distinct silience and conservation of large carnivores in the population segment of the Canada lynx and related rule; Rocky Mountains. Conservation Biology 10:964-976. final rule. Federal Register No. 65. Pp. 16051-16086. West, B. T., K. B. Welch, and A. T. Galecki. 2007. Linear mixed Walton, J. M., and K. E. Wynne-Edwards. 1997. Paternal models: a practical guide using statistical software. care reduces maternal hyperthermia in Djungarian Chapman & Hall, Boca Raton, FL.

Received 17 September 2010 Accepted for publication 17 February 2011

462 Olson et al.