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Science and Research Technical Report TR-13

Estimating the abundance of American

black bears (Ursus americanus) on the

Bruce Peninsula, Ontario

Science and Research Technical Report TR-13

Estimating the abundance of American black bear (Ursus americanus) on the Bruce Peninsula, Ontario

M.E. Obbard1, E.J. Howe1, C.J. Kyle2, J. Haselmayer3, J. Scheifley4

1 Wildlife Research and Monitoring Section, Science and Research Branch, Ontario Ministry of Natural Resources and Forestry

2 Natural Resources DNA Profiling and Forensics Centre, Trent University

3 Fathom Five and Bruce Peninsula National Park, Parks Canada Agency

4 Midhurst District, Ontario Ministry of Natural Resources and Forestry

2016

Science and Research Branch

Ministry of Natural Resources and Forestry

© 2016, Queen’s Printer for Ontario

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Cover photo: Shoreline of the Brue Peninsula, courtesy of Ontario Tourism Marketing

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Cite this report as: Obbard, Martyn E., Eric J. Howe, Chris J. Kyle, John Haselmayer,

Jody Scheifley. 2016. Estimating the abundance of American black bears (Ursus

americanus) on the Bruce Peninsula. Ontario Ministry of Natural Resources and

Forestry, Science and Research Branch, Peterborough, ON. Science and Research

Technical Report TR-13. 25p.

Some of the information in this document may not be compatible with assistive

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Science and Research Technical Report TR-13 Page | ii

Abstract

We estimated the population size of black bears on the entire Bruce Peninsula north of

Highway 21 and on the smaller area contained by Bruce Peninsula National Park and

interspersed lands by sampling bears noninvasively at 90 barbed wire hair corrals on 5

occasions in May and June of 2012. We extracted DNA from hair samples captured on

the barbed wire corrals, and identified individuals based on microsatellite genotyping at

14 loci combined with a gender test. We assumed that the height of the barbed wire

strand excluded cubs and yearlings from possibility of capture. Therefore, we estimated

density and population size of bears aged >1 year from the resulting individual

encounter histories using spatially explicit capture–recapture models. We calculated the

expected age and sex distribution of the population based on demographic data for

black bears elsewhere in Ontario so that an appropriate number of cubs and yearlings

could be included in the estimates of total population size.

We obtained 368 hair samples, of which 265 included >3 roots and were processed. Of

these, 184 were profiled to a sufficient number of loci to identify individuals. Seventy-

one unique individuals (30 females and 41 males) were detected a total of 117 times

(excluding duplicate detections of the same individual on the same trap and occasion).

We estimated that 316 black bears (SE 46.6, 95% confidence interval 225–408)

inhabited the entire Bruce Peninsula, and that 97 of these (SE 15.6, 95% confidence

interval 67–128) occupied Bruce Peninsula National Park and the interspersed lands.

Science and Research Technical Report TR-13 Page | iii

Résumé

Nous avons estimé, au cours des mois de mai et juin 2012, la population d’ours noirs

sur la totalité de la péninsule Bruce au nord de la Route 21 et dans la petite zone du

parc national du Canada de la Péninsule-Bruce et des terres disséminées en

échantillonnant les ours de façon non invasive, grâce à 90 stations de collecte de poils

à l’aide d’un fil barbelé. Nous avons extrait l’ADN des poils ainsi obtenus et avons

identifié les individus grâce au génotypage sur 14 loci microsatellites, combiné à un test

déterminant le sexe. Nous avons présumé que la hauteur du barbelé excluait les

oursons et les ours d’un an. Nous avons par conséquent estimé la densité et la taille de

la population des ours âgés >1 an à partir des témoignages de rencontres individuelles

à l’aide de modèles de capture-recapture spatialement explicites. Nous avons calculé la

répartition vraisemblable de l’âge et du sexe de la population d’après les données

démographiques pour les ours noirs ailleurs en Ontario, de sorte que le nombre

approximatif d’oursons et d’ours âgés d'un an puissent être inclus à l’estimation de la

population totale.

Nous avons obtenu 368 échantillons de poils, dont 265 comprenaient >3 racines et ont

été analysés. De ceux-ci, 184 ont permis d’identifier les individus grâce à un nombre

suffisamment élevé de loci. Soixante-et-onze individus distincts (30 femmes et

41 mâles) ont été repérés sur un total de 117 fois (exclusion faite des détections

doubles du même individu à la même station et la même fois). Nous avons estimé que

316 ours noirs (écart-type 46,6, intervalle de confiance de 95 %, écart 225–408)

habitaient la totalité de la péninsule Bruce et que de ceux-ci, 97 ours (écart-type 15,6,

intervalle de confiance de 95 %, écart 67–128) occupaient le parc national du Canada

de la Péninsule-Bruce et les terres disséminées.

Science and Research Technical Report TR-13 Page | iv

Contents

Abstract ........................................................................................................................ii

Résumé ....................................................................................................................... iii

Introduction .................................................................................................................. 1

Methods ....................................................................................................................... 2

Data analysis ............................................................................................................... 4

Results ......................................................................................................................... 8

Discussion ................................................................................................................. 13

Acknowledgements .................................................................................................... 15

Literature cited ........................................................................................................... 16

Science and Research Technical Report TR-13 1

Introduction

The population of American black bears (Ursus americanus) occupying the Bruce

Peninsula, Ontario, Canada is apparently geographically isolated. It represents a

conservation concern due to its small size (Howe et al. 2007), limited habitat (Obbard et

al. 2010a), and low genetic diversity (Mills 2005, Pelletier et al. 2011, 2012). In a

previous study, the population’s estimated risk of extirpation was highly dependent on

the current population size (Howe et al. 2007). Based on capture-recapture surveys

conducted in 2004 and 2009 in Bruce Peninsula National Park (BPNP), and in 2007 and

2009 south of BPNP on the Bruce Peninsula, the bear population was estimated to be

approximately 240 animals (95% CI, 114 – 336; MNRF unpublished data). However,

this estimate was considered to be unreliable due to the length of time between the

2004 and 2009 sampling efforts in BPNP, and low genotyping success from samples

collected in BPNP in 2009. In addition, some occupied bear habitat was not sampled in

those years, so it was necessary to extrapolate density estimates from the sampled

areas over unsampled areas to obtain an estimate of total population size. Accordingly,

in 2012 the Ontario Ministry of Natural Resources and Forestry (MNRF), Parks Canada

Agency, and Saugeen Ojibway Nation (Chippewas of Nawash First Nation and

Chippewas of Saugeen First Nation) collaborated to obtain an improved estimate of the

black bear population on the Bruce Peninsula by conducting a spatially comprehensive

survey.


Methods

Field sampling and DNA analysis

From May 23–June 28, 2012, we sampled black bears by collecting hair samples for

DNA analysis at barbed wire corrals (Woods et al. 1999). We assumed that the height

of the barbed wire strand (~50 cm above ground) would exclude cubs and yearlings

from the sample (Woods et al. 1999). We spaced 90 corrals throughout the peninsula in

an attempt to expose all bears to the possibility of capture (Figure 1). For logistical

reasons we were unable to place traps in the Township of Georgian Bluffs on the east

side of the peninsula between Wiarton and Owen Sound. We baited corrals with 3

partially opened tins of sardines in oil suspended from a board nailed 2.5 m high on a

tree. We firmly attached barbed wire strands to surrounding trees such that the wire was

> 2 m from the baited tree at any point along the wire to ensure bears could not reach

the bait without entering the corral. On approaching the bait, bears would either crawl

under or step over the wire strand, leaving a hair sample attached to a barb (Figure 2).

We baited sites first on May 23 and collected samples and rebaited corrals one week

later, ensuring any extra hairs were removed from barbs. We repeated this for a total of

5 sampling occasions. We air-dried hair samples in paper envelopes and stored them at

room temperature until DNA extraction was performed.

We did not attempt to extract DNA from hair samples with less than 3 roots. Individuals

were identified from their microsatellite genotypes at up to 14 polymorphic loci (Paetkau

and Strobeck 1994, Paetkau et al. 1995, Taberlet et al. 1997, Kitahara et al. 2000), and

sex was determined from amplification of a region of the amelogenin gene (Ennis and

Gallagher 1994). Individual microsatellite genotyping, gender determination, and

estimation of genotyping error (2.18%) were performed following the conditions

described in Pelletier et al. (2011, 2012). For additional details on methods for DNA

extraction, amplification, and profiling see Obbard et al. (2010b) and Pelletier et al.


(2011, 2012). Genotypes identified from a single sample were only considered to

represent a unique individual if they were genotyped to at least 11 loci.

Figure 1. Map of the Bruce Peninsula, Ontario, Canada. Red triangles show locations

of barbed wire hair corrals used in 2012. Landcover types are from the Southern

Ontario Land Resource Information System (Ministry of Natural Resources, 2008). The

integration mesh used in spatially explicit capture-recapture analyses appears as grey

dots; points within BPNP and interspersed lands are shown in darker grey. Heavy black

lines show boundaries used to define spatial covariates of bear density. ML = Miller

Lake; LH = Lion’s Head; WI = Wiarton.


Figure 2. Photograph of a black bear inside a barbed wire hair corral. When a bear

enters the corral to access the bait, a DNA sample may be obtained from hairs snagged

on the barbed wire (Photo: John Connor, MNRF)

Data analysis

We estimated population size using spatially explicit capture-recapture (SECR) models

(Efford 2004, Efford et al. 2009, Efford and Fewster 2013). The models assumed that:

(1) bears did not enter or leave the study area during sampling (demographic closure);

(2) individuals were accurately identified; (3) detections of different individuals were

independent events; and (4) individuals occupied approximately circular home ranges,

the central locations of which were fixed during sampling (Efford 2004). In the SECR

framework, probability of detection is modeled as a decreasing function of the distance

between traps and the unobserved central locations of individual home ranges or


“activity centres” (Efford 2004). The simplest detection function has two parameters: the

magnitude (g0) and spatial scale (σ) of a half-normal spatial detection probability

function; g0 may be thought of as the probability of detection of an individual animal

where a trap is placed at the individual’s activity centre (i.e., at distance zero), and σ

and the shape of the detection probability function describe how detection probability

declines with increasing distance between home range centre locations and traps

(Efford 2004). Animal density, g0, and σ may be described as functions of covariates

(Efford et al. 2009).

We defined a set of candidate SECR models with different combinations of the following

covariates of the parameters of the detection probability function and of bear density.

For g0, we considered general and trap-specific responses to initial detection (hereafter

denoted b and bk, respectively), individual heterogeneity (h), sex, and interactions

between behavioural responses and sex. For σ we considered unique values on all

sampling occasions (t), a linear trend over occasions (T), h, and sex. For bear density

we considered sex and six covariates for spatial variation. Spatial covariates were: (1) a

linear relationship with UTM Northings (hereafter denoted " N

"); (2) a 2-level factor

allowing for different densities north and south of UTM Northing 4996500 just north of

Miller Lake, ("ML"; Figure 1); (3) a 2-level factor allowing for differences north and south

of a line just south of Lion's Head ("LH"; Figure 1); (4) a 2-level factor allowing for

differences on either side of a line separating largely forested habitat north of the town

of Wiarton from largely agricultural habitat to the south and east ("WI"; Figure 1); (5) a

3-level factor employing the ML and WI boundaries; and (6) a 4-level factor employing

the ML, LH, and WI boundaries.

We initially defined the region of integration as the area within a 20-km buffer around

traps and set the number of mesh points in the x- and y-directions to 80 and 120,

respectively. We then removed mesh points that fell in open water, offshore islands,


cleared land, and developed areas using spatial data defining the outline of the Ontario

mainland and land cover data for southern Ontario (MNR 2008; Figure 1).

We fit SECR models by maximizing the full likelihood for proximity detectors (Efford et

al. 2009). We used the half-normal form of the detection probability function. Individual

heterogeneity was modeled using two-point finite mixture distributions (Pledger 2000).

To reduce the total number of models to be fitted, we did not consider all possible

subsets of the above covariates. We initially fit models with constant g0 and σ and each

covariate of spatial variation in density. We then emphasized models where density was

held constant or was a function of N

and fit models with various combinations of

covariates for g0 and σ to identify the best supported detection model. Finally, we

crossed the top detection model with all models of spatial variation in density. We used

Akaike’s Information Criterion for small sample sizes (AICc; Hurvitch and Tsai 1989) to

evaluate support for different candidate models, and compared density estimates from

high-ranking models.

We estimated sex-specific population sizes of bears aged > 1 year on the entire Bruce

Peninsula north of Highway 21, and within Bruce Peninsula National Park and the

interspersed lands (combination of lands of Saugeen Ojibway Nation [Chippewas of

Nawash First Nation and Chippewas of Saugeen First Nation] and private land), as the

volume under the fitted density surface described by the top-ranked model (Efford and

Fewster 2013). In the case of BPNP we limited the spatial extent of the population to the

area north of the former St. Edmund’s Township line by defining an appropriate

integration mesh (Efford and Fewster 2013; Figure 1). We summed sex-specific

estimates to estimate population size of all bears aged > 1 year. We calculated standard

errors (SE) of population estimates for both sexes as the square root of the sum of the

variances around sex-specific estimates, and 95% confidence limits as the point

estimate ± 1.96 SEs. Analyses were performed using R software (R Development Core

Team 2012) using the package "secr" (version 2.4.0, Efford 2012).


We used the RISKMAN population model (Taylor et al. 2003) to calculate the expected

population age distribution and hence the expected number of cubs and yearlings. We

parameterized RISKMAN with demographic rates reported by Kolenosky (1990;

reproductive rates), Yodzis and Kolenosky (1986; cub, yearling, and subadult survival

rates), and Obbard and Howe (2008; adult survival rates). We added the expected

number of cubs and yearlings to the estimated populations of bears aged > 1 year to

obtain estimates of total population size on the Bruce Peninsula north of Highway 21

and within BPNP and the interspersed lands.


Results

We obtained 368 hair samples, of which 103 consisted of fewer than 3 hairs with roots

and were not processed. Of the 265 samples processed, 184 were profiled to sufficient

loci to identify individuals. We identified 71 unique individuals (30 females and 41

males). Bears of both sexes were detected throughout the study area (Figure 3). Thirty-

one individuals were identified from a single sample, 18 were identified in 2 samples,

and 21 were identified in ≥ 3 samples. Sample size of recaptures was 46 (19 recaptures

of females and 27 recaptures of males).

One female moved > 19 km between traps during the fifth sampling occasion. The other

19 movements by females we detected averaged 2864 m (SE 495, maximum 5874).

Based on home-range information for black bears in similar habitat (Rogers 1987,

Powell et al. 1997, Schenk et al. 1998, Maxie 2009, Obbard et al. 2010a), and previous

hair-trapping studies conducted across Ontario (Obbard et al. 2010b, Howe et al. 2013),

we did not expect females to travel > 10 km between traps. The genotypes associated

with the 19-km movement matched at all 14 loci, and we verified all labels, so we are

confident that this was not a case of genotyping or transcription error. We are unaware

of any bears being translocated by management staff of either Parks Canada or the

Ontario Ministry of Natural Resources and Forestry during our study. Although we did

not expect foraging excursions to occur as early in the season as our sampling period,

the spring of 2012 was characterized by higher temperatures and lower precipitation,

compared to climate normals for 1981–2010 (Table 1), beginning with record highs over

much of the province in mid-March. As a result, bears may have been active earlier than

usual, and the phenological development of plants may have been advanced. Either

dispersal or a foraging excursion would violate the assumptions of the abundance

estimators. Furthermore, because our sample of movements among traps by females

was small, one outlier could affect our abundance estimates. Therefore, we censored

one of the two observations of this female.


Table 1. Temperature and precipitation values for March–June 2012 compared to

climate normals (in parentheses) for the period 1981–2010 for Wiarton, ON

(Environment and Climate Change Canada 2015).

Month Mean

Maximum

Temperature

(°C)

Mean

Minimum

Temperature

(°C)

Mean Daily

Temperature

(°C)

Total

Precipitation

(mm)

March 11.2 (2.7 ) 0.2 (-6.4) 5.7 (-1.9) 47.4 (67.4)

April 9.8 (10.3) -0.5 (0.4) 4.7 (5.3) 55.0 (73.1)

May 19.8 (16.5) 7.0 (5.4) 13.4 (11.0) 24.2 (83.5)

June 23.3 (21.5) 12.6 (10.3) 18.0 (15.9) 77.9 (76.4)

Figure 3. Locations where hair samples were obtained for female (left) and male (right)

American black bears on the Bruce Peninsula, Ontario, 2012. Dots indicate trap

locations where hair samples were obtained. Crosses indicate remaining trap locations.


High-ranking models of spatial detection probability included (positive) trap-specific

responses to initial detection and individual heterogeneity affecting g0, and differences

in σ between sexes and among individuals of the same sex (Table 2). Top models also

included differences in sex-specific g0 and effects of initial detection on g0 (Table 2). The

best supported model of variation in bear density was a linear relationship with y-

coordinates, where bear density increased with increasing latitude (Table 2). Neither

differences in σ among sampling occasions nor differences in density between the

sexes were supported (Table 2). We attempted to fit models with each form of variation

in bear density crossed with the best-supported detection model. However,

convergence problems and singularities arose when the top detection model was

crossed with ML, LH, and the four-level covariate for density, so AICc-values and

parameter estimates from these models are not presented. The top two AICc-ranked

models accounted for 97% of the total AICc weight (Table 2) and yielded similar

estimates of the detection function parameters and bear density. Densities of bears

aged > 1 year estimated from the top model were 26.8/100 km2 (SE 6.7) in the

northeast corner of BPNP, 20.0/100 km2 in the vicinity of Miller Lake, 12.6/100 km2 20

km north of Wiarton, and 6.4/ 100 km2 10 km south of Wiarton. Densities estimated from

the 2nd-ranked model were 26.0/100 km2 north of Miller Lake, 12.2/100 km2 between

Miller Lake and Wiarton, and 5.6/100 km2 south of Wiarton. The top AICc-ranked model

had nearly 4 times as much support as the second-ranked model (Table 2), so we used

the top model to estimate population size.

Population size of bears aged > 1 year on the Bruce Peninsula estimated from the fitted

density surface was 202.2 bears (SE 29.8, 95% CI 144–261). Population size of bears

aged > 1 year within Bruce Peninsula National Park and all interspersed lands was 62.1

(SE 10.0, 95% CI 43–82). Thirty-six percent of bears in the expected age/sex

distribution were cubs and yearlings. Therefore, we divided population estimates of

bears aged > 1 year by 0.64 to convert them to population estimates for all bears. This


yielded an estimate of 316 bears of all ages (SE 46.6, 95% CI 225–408) on the

peninsula north of Highway 21, and 97 bears of all ages (SE 15.6, 95% CI 67–128)

within BPNP and all interspersed lands.

Table2. AICc model selection criteria among spatially explicit capture-recapture models

of detection probability and density of black bears on the Bruce Peninsula, Ontario,

2012.

Density model Detection model npar logLik AICc ΔAICc wi

UTM N g0(h+bk×sex) σ(h+sex) 11 -458.8 944.0 0.00 0.77

3-level factor g0(h+bk×sex) σ(h+sex) 12 -458.7 946.7 2.72 0.20

UTM N g0(h+bk) σ(h+sex) 9 -465.3 951.5 7.52 0.02

UTM N g0(h×bk) σ(h+sex) 10 -464.0 951.7 7.67 0.02

UTM N g0(h+bk×sex) σ(sex) 10 -466.9 957.5 13.55 0.00

UTM N + sex g0(h+bk×sex) σ(h+sex) 12 -464.3 958.1 14.07 0.00

UTM N g0(bk×sex) σ(h+sex) 10 -472.3 968.3 24.31 0.00

UTM N g0(bk×sex) σ(sex) 8 -478.0 974.3 30.28 0.00

UTM N g0(bk×sex) σ(T+sex) 9 -478.0 976.9 32.90 0.00

UTM N + sex g0(bk×sex) σ(sex) 9 -478.0 976.9 32.91 0.00

UTM N g0(bk+sex) σ(sex) 7 -481.1 978.1 34.07 0.00

UTM N + sex g0(bk×sex) σ(T+sex) 10 -478.0 979.6 35.61 0.00

UTM N g0(bk) σ(sex) 6 -486.6 986.5 42.52 0.00

Constant g0(bk) σ(sex) 5 -491.2 993.3 49.30 0.00


Density model Detection model npar logLik AICc ΔAICc wi

Constant g0(bk) σ(T+sex) 6 -491.1 995.5 51.55 0.00

Constant g0(bk) σ(t+sex) 9 -490.4 1001.7 57.67 0.00

Constant g0(b) σ(sex) 5 -511.4 1033.7 89.71 0.00

Constant g0(.) σ(sex) 4 -515.5 1039.5 95.51 0.00

UTM N g0(.) σ(.) 4 -520.1 1048.7 104.73 0.00

LH g0(.) σ(.) 4 -520.7 1050.1 106.11 0.00

3-level factor g0(.) σ(.) 5 -520.9 1052.6 108.63 0.00

WI g0(.) σ(.) 4 -522.2 1053.0 109.03 0.00

BPNP g0(.) σ(.) 4 -522.3 1053.2 109.25 0.00

4-level factor g0(.) σ(.) 6 -520.1 1053.5 109.51 0.00

Constant g0(.) σ(.) 3 -525.3 1057.0 112.97 0.00


Discussion

The population estimate we developed relied on several assumptions. In order to meet

the assumptions of demographic closure and static home range centre locations, we

sampled during spring and early summer to ensure that we completed sampling prior to

when bears might leave their spring and early summer home ranges on seasonal

feeding forays (Rogers 1987, Schenk et al. 1998, Noyce and Garshelis 2011), and

before subadult males would be likely to disperse (Lee and Vaughan 2003). Despite the

early spring in 2012 (Table 1), we had little evidence of large-scale movements by bears

during the study; therefore, the assumption of static home range centres was met. The

timing and duration of our sampling ensured that no cubs were born and that mortality

was minimal (none was observed or reported) during sampling, so the assumption of

demographic closure was adequately met. Culling of low-quality samples and profiling

all samples to 14 loci plus gender reduced the potential for violations of the assumption

that marks were not lost or misread. Violation of the assumption of circular home

ranges, if it occurred, should affect only the variance of density estimates (Efford 2004).

We cannot verify that the height of the wire strand excluded cubs and yearlings from the

sample. However, Drewry et al. (2012) did not find hair samples where remote cameras

revealed that small bears had passed under a barbed wire strand set at 40 cm above

the ground, which was 10 cm lower than the level of our barbed wire. They concluded

that they had likely detected a few cubs and yearlings, but that their density estimates

primarily reflected subadult and adult density. If we detected more than one member of

a family group traveling together, then the assumption of independence of captures


could have been violated. Furthermore, if any bears < 2 years of age were sampled, we

overestimated the total population when we added the expected number of cubs and

yearlings to population estimates for bears aged > 1 year. However, based on

observations and morphological measurements of black bears in Ontario (M.E. Obbard,

unpublished data) a consistent wire height of 50 cm should exclude cubs and yearlings,

and we are confident it did so.

Bears occupying some patches of suitable habitat may not have been exposed to our

trap array and been vulnerable to capture. However, estimating the density surface

across the entire region of integration enabled us to estimate the number of bears

occupying the entire peninsula, including areas where no traps were located (Efford and

Fewster 2013). Bear density under the fitted surface from the selected SECR model

increased with latitude. Therefore, the number of bears in the northeastern (portions of

Cabot Head) and northwestern (vicinity of town of Tobermory) areas of the peninsula

where no traps were placed was estimated assuming maximal density, and the number

of bears south of Wiarton, including in the Township of Georgian Bluffs, was estimated

assuming minimal density. If bears were not at high density in the northernmost portions

of the peninsula, population size on the peninsula and within BPNP and interspersed

lands may have been overestimated, though we expect bias would be slight. By

including all forest and wetland patches in our integration mesh we may have inferred

the presence of bears where they do not actually occur. This could also result in a slight

overestimation of population size. Nevertheless, we derived population estimates for the

Bruce Peninsula north of Highway 21 and for Bruce Peninsula National Park and

interspersed lands that were based on a sufficient number of captures and re-captures

to provide reliable estimates. Our results confirm that the population size of black bears


on the Bruce Peninsula is small, and highlight that this should be a consideration in

land-use planning and harvest management.

Acknowledgements

Field sampling was conducted by members of the Ontario Ministry of Natural Resources

and Forestry, Bruce Peninsula National Park, and Saugeen Ojibway Nation. We

especially thank Doran Ritchie (Saugeen Ojibway Nation), Cavan Harpur (BPNP), and

Dustin Veenhof (MNRF) for their assistance with sample collection. Genetic analyses

were performed at the Natural Resources DNA Profiling and Forensics Centre at Trent

University, Peterborough, Ontario. Thanks to Kevin Middel (MNRF) for preparing Figure

1. We are grateful to the many private landowners who permitted us to sample bears on

their land.


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