Population Growth and Mortality Sources of the Black Bear Population in Northern Georgia, AR Little, A Hammond, JA Martin

Tags: population growth, northern Georgia, Journal of Wildlife Management, bear population, Annual Conference, black bear, Northern Georgia Little, population reconstruction, JSAFWA Black Bear Population Growth, harvest, Southeastern Association of Fish and Wildlife Agencies, Georgia Department of Transportation, black bears, North Carolina, Chattahoochee, Bear hunting, included, Coosawattee-Carter's Lake, Physiographic regions, Tallulah Gorge, Chestatee, Hellgren, black bear population, reconstruction period, Ridge and Valley, fall months, Pine Log, McGraw Ford, Lake Russell, J.W. McCown, M. Hebblewhite, Florida, Georgia, southeastern North Carolina, Wildlife Monographs, Georgia Office of Planning and Budget, illegal harvest, Results Mortality events, Duke's Creek, Coosawattee, Rich Mountain, Lake Burton, Coopers Creek, Blue Ridge, Dawson Forest, Swallow Creek
Content: Population Growth and Mortality Sources of the Black Bear Population in Northern Georgia Andrew R. Little, Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602 Adam Hammond, Georgia Department of Natural Resources, Wildlife Resources Division, 2592 Floyd Springs Rd. NE, Armuchee, GA 30105 James A. Martin, Warnell School of Forestry and Natural Resources, Savannah River Ecology Lab, University of Georgia, Athens, GA 30602 Kristina L. Johannsen, Georgia Department of Natural Resources, Wildlife Resources Division, 2065 U.S. 278 SE, Social Circle, GA 30025 Karl V. Miller, Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602
Abstract: An understanding of black bear (Ursus americanus) population trends and cause-specific mortality is needed to direct management decisions in northern Georgia given an increasing human population. Therefore, we evaluated black bear population trends and mortality sources across 26 counties and 18 Wildlife Management Areas in northern Georgia from 1979­2014. We collected harvest data from 6,433 individuals during the study period. Using age-at-harvest data, population reconstruction illustrated an increasing trend in the bear population for both males (=1.113) and females (=1.108). Bait station indices reflected a similar increase in the bear population based on increased visitation over time (min: 12.3% visitation in 1983; max: 76.7% visitation in 2009). Bear-vehicle mortalities also increased from 1986­2014 and were greater for males relative to females, especially males 2 years old. Bear-vehicle mortalities were greater for males than for females during May­July; however, bear-vehicle mortalities increased for both sexes during August­November. Current population trajectory suggests black bear populations in northern Georgia will continue to increase. If bear population trends continue to increase, we suggest further evaluation of current bear harvest regulations in northern Georgia to reduce potential bear-human conflicts.
Journal of the Southeastern Association of Fish and Wildlife Agencies 4:130­138
Black bears (Ursus americanus) were nearly extirpated from Georgia by the 1930s due to unregulated hunting, illegal harvest, and large-scale habitat loss (Carlock et al. 1983). Subsequently, hunting season was prohibited to promote population recovery from the early 1920s to 1979 (Carlock et al. 1983). In 1979, the Georgia Department of Natural Resources, Game and Fish Division re-initiated a limited bear hunting season. Today, black bears occur in three distinct populations in Georgia in the northern, central, and southern regions of the state; the largest population is located in northern Georgia, which is associated with the southern region of the Appalachian mountain range. Vehicle collisions have been shown to be a strong source of mortality for bears (Wooding and Brady 1987, Brody and Pelton 1989, Warburton et al. 1993, Wooding and Hardisky 1994, Garrison et al. 2007). Human populations and associated vehicle traffic are expected to increase 46% in Georgia by 2030 (Georgia Office of Planning and Budget 2010). Therefore, we evaluated bear population trends and mortality sources to direct future population management decisions (e.g., regulation change) given the expected increase in the human population in Georgia. During early summer, male bears are at the greatest risk of vehicle mortality (Warburton et al. 1993), a time which corresponds to breeding season and dispersal movements (Hamilton 1978, Hellgren and Vaughan 1990). During late summer and fall, males and females have been found to be equally vulnerable to vehicle mor-
tality (Warburton et al. 1993). Food acquisition prior to denning likely increases vulnerability to vehicle mortality in these seasons (Rogers 1987). Hellgren and Vaughan (1990), for example, found females made extensive shifts in their home ranges during the late summer and early fall to locate natural fall foods (e.g., oak mast). Black bear populations are primarily managed through legal harvests (Bunnell and Tait 1985, Warburton et al. 1993). In 1979, hunters in northern Georgia harvested 21 bears during the first legal bear hunting season on Chattahoochee, Chestatee, Cooper's Creek, and Rich Mountain Wildlife Management Areas (WMAs; Carlock et al. 1983). In 2013, the harvest and harvest area expanded to 386 bears across 12 WMAs and 22 counties (Georgia Department of Natural Resources, unpublished data). These data suggest the bear population is increasing in northern Georgia; however, limited information currently exists on current population trajectory. We evaluated historical black bear population trends (1979­2014) and characteristics of mortality (harvest and vehicle-collisions) in northern Georgia. Our research objectives were to: (1) document sources of mortality (legal harvest, known illegal harvest, and bearvehicle mortalities), (2) evaluate population growth using population reconstruction techniques, and (3) evaluate trends in bearvehicle mortalities. We predicted that legal harvest would be the greatest source of mortality followed by bear-vehicle mortalities and known illegal harvest. We also predicted that younger males
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Black Bear Population Growth and Mortality in Northern Georgia Little et al.131
(2 years old) would constitute the majority of mortalities given their increased home range size and dispersal behaviors relative to females (Hamilton 1978, Hellgren and Vaughn 1989). Finally, we predicted that bear-vehicle mortalities would increase during the study primarily, and that the majority of bear-vehicle mortalities would occur during the fall months when bears were searching for food resources prior to denning. study area Our study was conducted in 26 counties and 18 WMAs in northern Georgia representing a total of 21,651.7 km2 (Figure 1). The counties included: Banks, Bartow, Catoosa, Chattooga, Cherokee, Cobb, Dade, Dawson, Fannin, Floyd, Forsyth, Gilmer, Gordon, Gwinnett, Habersham, Hall, Lumpkin, Murray, Pickens, Rabun, Stephens, Towns, Union, Walker, White, and Whitfield. The WMAs Figure 1. Black bear (Ursus americanus) mortality study area in northern Georgia.
included: Allatoona, Blue Ridge, Chattahoochee, Chestatee, Cohutta, Coopers Creek, Coosawattee-Carter's Lake, Coosawattee, Dawson Forest, Duke's Creek, Lake Burton, Lake Russell, McGraw Ford, Pine Log, Rich Mountain, Swallow Creek, Tallulah Gorge, and Warwoman. Physiographic regions included in this study area included Blue Ridge Mountains, Ridge and Valley, and Upper Piedmont. Methods Mortality events Bear hunting was permitted in the fall of each year with a limit of 1 bear per hunter from 1979­2010. In 2011, hunting regulations in northern Georgia were changed in to allow the harvest of 2 bears per hunter. Harvest of females with cubs or bears weighing <34 kg (live-weight) and use of bait when hunting was prohibited. No spring bear harvest was permitted in Georgia. Registration of harvested black bears is mandatory; therefore, Georgia Department of Natural Resources (hereafter, Georgia DNR) personnel recorded biological data from all harvested bears including sex, age, and weight. Additionally, hunter information was collected including county or WMA of harvest and method of harvest (rifle, shotgun, crossbow, handgun, muzzleloader, or archery). Records of registered hunter harvested bears were used to calculate total harvest during the study period. Georgia DNR personnel extracted a premolar for aging using cementum annuli (Willey 1974). All teeth were sectioned and aged at Matson's Laboratory (Manhattan, Montana). Bear hunting was permitted in the counties and WMAs beginning in mid-September for archery equipment and in mid-October for muzzleloaders and modern firearms; it ended in early December. Use of dogs for hunting bear was prohibited. Illegal harvest (e.g., use of bait, harvest of bears weighing <34.0 kg, bears harvested outside of legal hunting season, etc.) did occur during the study period. When bears were illegally harvested, conservation law enforcement officers confiscated the carcasses and/or issued a citation. Using the mortality data, we determined: 1) percentages of legal harvest, known illegal harvest, and bears killed by vehicles; 2) percentages of harvest by legal weapon type; 3) percentages of harvest mortality by age class; and 4) percentages of vehicle mortality by sex and age class. Bears killed by vehicles were reported to the local 911 center following a collision and/or accident reports from law enforcement officers. We calculated percentages of legal harvest, known illegal harvest, and vehicle mortality by totaling the number of mortalities in each category and dividing by the total number of mortality events during the study period multiplied by 100. We calculated percentages of harvest by legal weapon type by totaling the number of mortalities by each type of weapon (archery/cross-
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Black Bear Population Growth and Mortality in Northern Georgia Little et al.132
bow, handgun, muzzleloader, rifle, and shotgun) and dividing by the total number of mortality events during the study period multiplied by 100. We calculated percentages of harvest mortality and vehicle mortality by sex and age class (cubs: 0.25­0.75 years old; yearlings: 1­1.75 years old; 2-year-old: 2­2.75 years old; 3-yearold: 3­3.75 years old, and 4+ year old) by totaling the number of mortalities in each age class and dividing by the total number of mortality events during the study period multiplied by 100. Population trends We used population reconstruction to estimate bear population growth (Downing 1980). Population reconstruction is a population estimation technique that uses age-at-harvest data and backward addition of cohorts to estimate minimum population size over time and is commonly used by state agencies for black bear and white-tailed deer (Odocoileus virginianus) population estimation (Davis et al. 2007). The advantage of population reconstruction is that it requires only total harvest by year and age-at-harvest by year (Downing 1980) and can be used by biologists and managers to identify trends in abundance over time (Tilton 2005). We analyzed sexes separately because males and females may experience differing levels of harvest mortality. We collapsed ages into five classes as previously defined for males and females. We reconstructed the population from 1979­2014 using program PopRec2011 (Pond and Property, LLC, Newport, Virginia), which uses Downing's (1980) method of population reconstruction. For years of complete reconstructed cohorts, we calculated the annual population growth rate (t) as t=Nt+1/Nt where Nt was the total reconstructed abundance in year t. We censored years 2012­2014 due to incomplete cohorts; therefore, our final reconstructed population was from 1979­2011. The assumptions of Downing's (1980) population reconstruction include: 1) the proportion of deaths accounted for is constant over time for each cohort; 2) the Mortality rates for the oldest two reconstructed age classes are equal; and 3) subsamples of ages are unbiased. Population reconstruction does not account for deaths due to natural mortality thus reconstructed abundances are underestimates of total population abundance (Davis et al. 2007). We recognize the potential problems with population reconstruction resulting from biases in aging and variability in mortality rates (Roseberry and Woolf 1991). However, this method has been found to be suitable for estimating population growth rate () for populations experiencing no trend in harvest rate or natural mortality rate over time, and is especially valuable with estimating black bear populations (Davis et al. 2007).
We also used bait-station surveys as an index to population abundance and distribution, and to evaluate relative trends in the bear population over time (Clark et al. 2005). Bait-station surveys were conducted in 11 counties and on 10 WMAs covering a linear distance of approximately 451 km of bear habitat from 1983­2013. Surveys were conducted annually or biannually in July. Each baitstation survey route consisted of 5­26 bait sites (Їx=13) and were established along paved and gravel roads, major trails, and wooded paths. Bait-stations were spaced approximately 0.81 km apart. A bait station was comprised of three partially opened cans of sardines hung in a small tree >3 m above the ground. Each site was checked after five nights and bear visits were determined based on claw marks on the tree trunk or canine tooth-sized holes in the sardine can (Johnson 1990). We pooled all bait stations for each WMA and then pooled all WMAs sampled in northern Georgia to calculate an annual percentage of bait sites visited by bears. We used bear-vehicle mortality data collected by Georgia DNR personnel to evaluate trends in mortality over time. Bear-vehicle mortality data were available from 1986­2014 from all 26 counties in our study area. We modeled bear-vehicle mortalities as a function of year using a negative binomial generalized linear mixed model implemented in program R version 3.1.3 (R Core Team 2013). We included county as a random effect to account for spatial variation in bear-vehicle mortalities (Gillies et al. 2006). We also included total vehicle miles travelled (or traffic volume) as an offset in the model to account for variation in traffic trends by county over time since bear-vehicle collisions are increasingly likely in areas with increased traffic volume. We collected traffic volume data from the Georgia Department of Transportation (2016). We used vehicle miles traveled (VMT), a measure of traffic volume, which is calculated as the product of traffic volumes on road sections (urban and rural) and the length of those road sections for each county (S. Susten, Georgia Department of Transportation, personal communication). Additionally, we evaluated the relationship between the number of bear-vehicle mortalities and estimated population size based on population reconstruction using a simple linear regression modelling framework. We also included total vehicle miles travelled as an offset in the model to account for variation in traffic trends across the entire study area. We evaluated bear-vehicle mortalities by month to determine when males and females were most vulnerable to collisions. We used a Chi-square goodness of fit test to evaluate whether males or females were more vulnerable to bearvehicle mortalities. We analyzed the monthly vehicle collision data by sex in program R version 3.1.3. We used an alpha level of 0.05.
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Black Bear Population Growth and Mortality in Northern Georgia Little et al.133
Results Mortality events We documented 6,433 black bear mortalities from 1979­2014. Of this total, legal harvest comprised 90.5% (n=5,821), bear-vehicle mortality 7.1% (n=454), and known illegal harvest 2.5% (n=158; Table 1). Bears were primarily harvested by rifle (64.0%), followed by archery (28.7%), muzzleloader (5.8%), and unknown weapon (1.1%), shotgun (0.2%), and handgun (0.1%; Table 2). Ages were estimated for 95.0% of all harvested bears (n=5,658, legal and known illegal) and for 58.8% of all bear-vehicle mortalities (n=267) from 1979­2014. We found the proportions of males and females harvested legally differed by age class (X2=622.29, df=4, P<0.001). Males (2 years old) were most likely to be legally harvested; whereas, females (4 years old) were most likely to be legally harvested (Table 3). We assessed known illegal harvest by sex and age group and found the proportions of males and females harvested illegally did not differ by age class (X2=5.54, df=4, P=0.236; Table 3). Population trends Minimum population size of black bears has increased during 1979­2011 (Figure 2). Annual population growth rate () for males and females was 1.113 and 1.108, respectively. Bear bait station indices also reflected an increasing population trend based on increased visitation over time (=2.14; r2=0.94; min: 12.3% visitation in 1983; max: 76.7% visitation in 2009; Figure 3). The earliest reported bear-vehicle mortality occurred in 1986. The number of bear-vehicle mortalities increased 8.7% (SE=0.009, P<0.001) annually after adjusting for county-level vehicle traffic volume. This is further illustrated by an increasing number of bearvehicle mortalities from 1986­2014 (min=0 [1987 and 1988]; Їx =16.6; max=68 [2009]; Figure 4). We also found a positive relationship between the number of bear-vehicle mortalities and the increasing bear population (=0.0019; SE=0.0002; r2=0.57; P<0.001; Figure 5). For subsequent analyses, we omitted 42 bears from the total vehicle-kill (9.3%; 42 of 454) because sex was unknown. Of the remaining 412 bears (253 males and 159 females), we assessed bear-vehicle mortalities by month for male and females. Bear-vehicle mortalities occurred in all months when totaled for all years from 1979­2014 (Figure 6). Proportions of males and females killed by vehicles differed during the year (X2=29.75, df=11, P=0.002); differences in road mortality between males and females were greatest from May to July. However, both sexes (male, 67.3%; female, 47.8%) were more vulnerable to collisions during August to November. We also assessed bear-vehicle mortalities by sex and age group and found the proportions of males and females killed by vehicles differed by age class (X2=28.59, df=4, P<0.001;
Table 1. Number of black bears (Ursus americanus) mortalities due to legal harvest, known illegal harvest, and bear-vehicle collisions in northern Georgia, 1979­2014.
Year
Legal harvest Illegal harvest
Vehicle-kill
1979
21
0
0
1980
32
0
0
1981
18
0
0
1982
27
0
0
1983
18
0
0
1984
18
0
0
1985
23
0
0
1986
17
0
2
1987
24
2
3
1988
64
1
0
1989
40
1
0
1990
89
1
2
1991
59
0
2
1992
73
5
13
1993
125
1
5
1994
111
0
3
1995
156
8
5
1996
102
7
7
1997
158
15
10
1998
197
6
10
1999
218
7
4
2000
242
2
23
2001
225
6
8
2002
206
8
15
2003
257
15
21
2004
156
3
17
2005
258
14
13
2006
249
4
8
2007
285
8
39
2008
320
8
27
2009
423
15
70
2010
286
7
26
2011
531
3
30
2012
260
0
15
2013
386
11
63
2014
147
0
13
Total
5,821
158
454
Table 2. Number of black bears (Ursus americanus) harvested (legal and known illegal) by weapon type in northern Georgia, 1979­2014.
Legal harvest
Illegal harvest
Weapon type
%
na
%
na
Archery/crossbow Handgun Muzzleloader Rifle Shotgun Unknown Total
28.7
1673
0.1
7
5.8
340
64.0
3726
0.2
11
1.1
64
100
5821
18.4
29
0.6
1
2.5
4
53.2
84
1.9
3
23.4
37
100
158
a. We censored harvest data where weapon type was unknown.
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Black Bear Population Growth and Mortality in Northern Georgia Little et al.134
Table 3. Known sex and age structure of black bear (Ursus americanus) mortalities due to legal harvest, known illegal harvest, and bear-vehicle collisions in northern Georgia, 1979­2014.
Legal harvest
Illegal harvest
Bear-vehicle mortalities
Age class Cubsb Yearlingsc 2 year olds 3 year olds Adultsd Total
Male (%) Female (%)
na
1.0
0.7
93
23.1
11.
1898
15.5
9.4
1381
7.0
5.8
704
6.9
9.4
1459
53.5
46.5
5535
Male (%) Female (%)
na
4.9
5.7
13
15.4
14.6
37
12.2
4.9
21
8.1
4.9
16
21.1
8.1
36
61.8
38.2
123
Male (%) Female (%)
na
5.6
3.7
25
22.1
6.0
75
18.7
5.6
65
7.9
5.2
35
10.1
15.0
67
64.4
35.6
267
a. We censored harvest data where age information was unknown. b. <1 year old. c. 1 year old. d. 4 years old.
Figure 2. Reconstruction of population size for male and female black bears (Ursus americanus) in northern Georgia, 1979­2011. We censored population estimates for 2012­2014 because incomplete age class data were available. 2017 JSAFWA
Black Bear Population Growth and Mortality in Northern Georgia Little et al.135 Figure 3. Annual percentage of bait-stations visited by bears (Ursus americanus) in northern Georgia, 1983­2013. Figure 4. Total number of black bears (Ursus americanus) killed by vehicles by year in northern Georgia, 1986­2014. 2017 JSAFWA
Black Bear Population Growth and Mortality in Northern Georgia Little et al.136
Table 3). Males (2 years old) were most vulnerable to vehiclecollisions; whereas, females (4 years old) were most vulnerable to vehicle-collisions (Table 3).
Discussion Our results illustrate an increasing black bear population over the past 35 years in northern Georgia with 1.113 and 1.108 annual population growth for males and females, respectively. Bear populations have been increasing throughout North America with black bears currently occupying 59% of their historical range (Ripple et al. 2014). Specifically, in the southeastern United States, state agencies have reported increasing black bear population trends (Telesco 2013). We note that population reconstruction estimates are conservative given that this technique provides minimal population estimates (Davis et al. 2007). State wildlife agencies typically use reconstructed population estimates to identify trends in abundance over time (Tilton 2005). Roseberry and Woolf (1991) noted potential biases in aging and variability in mortality rates and their influence on population reconstruction outcomes. Davis et al. (2007) also found that changes in management and harvest rates during
Figure 5. Predicted bear-vehicle collisions based on bear population size in northern Georgia, 1986­2014.
Figure 6. Total number of male and female black bears (Ursus americanus) killed by vehicles by month in northern Georgia, 1986­2014. 2017 JSAFWA
Black Bear Population Growth and Mortality in Northern Georgia Little et al.137
the reconstruction period would result in an underestimation of the population growth rate. We believe we met all the assumptions of the Downing's population reconstruction method and suggest that our results provide a conservative estimate of population growth. Furthermore, we used bait station indices as additional evidence to support the population reconstruction estimates. Another limiting aspect of population reconstruction is the lack of confidence intervals. We suggest our results be used as an index of abundance because it consistently underestimates true abundance. future research should focus on new methodologies to improve confidence in black bear population estimates such as statistical population reconstruction (Clawson 2015). Legal harvest accounted for the majority of bear mortality and was biased towards younger males (2 years old), which is likely related to home range size, breeding, and dispersal behaviors (Hamilton 1978, Hellgren and Vaughn 1989). Our results indicate that harvest of younger females (2 years old) was lower than younger males (2 years old). For example, males (2 years old) comprised 74.0% of males harvested; whereas, females (2 years old) comprised only 45.8% of females harvested. We did observe increased harvest pressure on older age females (4 years old), which is likely related to home range expansion in the fall to find adequate food resources prior to denning (Alt et al. 1980, Rogers 1987, Hellgren and Vaughn 1990). Our study shows that bear-vehicle mortalities were greater for males relative to females during May to July. Our findings are consistent with previous research (Hamilton 1978, Hellgren and Vaughn 1990, Warburton et al. 1993). Increased movements associated with breeding and dispersal during this time period likely increases their vulnerability to bear-vehicle mortalities (Hamilton 1978, Hellgren and Vaughan 1990). For example, in coastal North Carolina and Virginia, Hellgren and Vaughn (1990) found mean male home range size during early to late summer ranged from 10.7­16.2 km2; whereas, mean female home range size during early to late summer ranged from 4.6­6.9 km2. Bear-vehicle mortalities increased during late summer and fall for both sexes. Our results are supported by previous research that found both sexes were equally vulnerable to vehicle mortalities during the late summer and fall months (Warburton et al. 1993). We suggest the most plausible explanation for the vulnerability to bear-vehicle mortalities amongst sexes during the fall months is the acquisition of food resources. Bears commonly select for high energy foods during fall months to increase fat content (Landers et al. 1979, Rogers 1987) in preparation for the winter denning period. Previous research has also documented extensive home range shifts during late summer and fall months for both males and females (Hellgren and Vaughn 1990). Additionally, they found
that home range shifts for females during late summer and fall months were primarily influenced by spatial and temporal distribution in food resources. Similarly, Alt et al. (1980) found female movements were greater than male movements during September and October in northeastern Pennsylvania. We also found vehicle mortalities for females were greater than for males in August and September, suggesting females are moving greater distances to locate food resources. Management Implications Overall, our findings provide evidence of an increasing black bear population in northern Georgia with legal rifle harvest acting as the primary source of mortality. The increasing bear population has led, in turn, to increased human-bear conflicts such as bearvehicle mortalities. We suggest biologists can mitigate human-bear conflicts, if so desired, by adjusting harvest regulations. However, we also suggest biologists consider alternative methods to reduce bear-human conflicts, especially in areas where hunting is not permitted. Acknowledgments We thank Georgia Department of Natural Resources, Wildlife Resources Division personnel for assistance with data collection. In particular, we thank S. Frazier for assistance with data collection. We thank the Georgia Department of Transportation for their assistance with collecting traffic volume data used in this project. In particular, we thank S. Susten and E. Adams with the Georgia Department of Transportation for their assistance on this project. Literature Cited Alt, G.L., G.J. Matula, F.W. Alt, and J.S. Lindzey. 1980. Dynamics of home range and movements of adult black bears in northeastern Pennsylvania. InterNational Conference on Bear Research and Management 4:131­136. Brody, J.A. and M.R. Pelton. 1989. Effects of roads on black bear movements in western North Carolina. Wildlife Society Bulletin 17:5­10. Bunnell, F.L. and D.E.N. Tait. 1985. Mortality rates of North American bears. Artic 38:316­323. Carlock, D.M., R.H. Conley, J.M. Collins, P.E. Hale, K.G. Johnson, A.S. Johnson, and M.R. Pelton. 1983. The tri-state black bear study. Tennessee Wildlife Resource Agency Technical Report No. 83-9, Knoxville. Clark, J.D., F.T.V. Manen, M.R. Pelton. 2005. Bait stations, hard mast, and black bear population growth in Great Smoky Mountains National Park. Journal of Wildlife Management 69:1633­1640. Clawson, M.V. 2015. Management application statistical population reconstruction to wild game populations. Doctoral Dissertation. University of Washington, Seattle, Washington. Davis, M.L., J. Berkson, D. Steffen, and M.K. Tilton. 2007. Evaluation of accuracy and precision of Downing Population Reconstruction. Journal of Wildlife Management 71:2297­2303. Downing, R.L. 1980. Vital statistics of animal populations. Pages 247­267 in S.D. Schemnitz, editor. Wildlife Techniques Manual. The Wildlife Society, Washington, D.C.
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Garrison, E.P., J.W. McCown, and M.K. Oli. 2007. Reproductive ecology and cub survival of Florida black bears. Journal of Wildlife Management 71:720­727. Georgia Department of Transportation. 2016. GDOT-Crash, Road and Traffic Data. http://www.dot.ga.gov/DS/Data#tab-2. Accessed 1 Mar 2016. Georgia Office of Planning and Budget. 2010. Georgia 2030 Population Projections. http://www.georgialibraries.org/lib/construction/georgia_popula tion_projections_march_2010.pdf. Accessed 20 May 2016. Gillies, C.S., M. Hebblewhite, S.E. Nielsen, M.A. Krawchuk, C.L. Aldridge, J.L. Frair, D.J. Saher, C.E. Stevens, and C.L. Jerde. 2006. Application of random effects to the study of resource selection by animals. Journal Animal Ecology 75:887­898. Hamilton, R.J. 1978. Ecology of the black bear in southeastern North Carolina. Master's Thesis. University of Georgia, Athens. Hellgren, E.C. and M.R. Vaughn. 1990. Range dynamics of black bears in Great Dismal Swamp, Virginia­North Carolina. Proceedings of the Annual Conference of the Southeastern Association of Fish and Wildlife Agencies 44:268­278. Johnson, K.G. 1990. Bait-station surveys to monitor relative density, distribution, and activities of black bears in the southern Appalachian region. Annual Progress Report, University of Tennessee, Knoxville. Landers, J.L., R.J. Hamilton, A.S. Johnson, and R.L. Marchinton. 1979. Foods and habitat of black bears in southeastern North Carolina. Journal of Wildlife Management 43:143­153. R Core Team. 2013. A Language and Environment for Statistical Computing. R Foundation forStatistical Computing, Vienna, Austria.
Ripple, W.J., et al. 2014. Status and ecological effects of the world's largest carnivores. Science 343:1241484. DOI: 10.1126/science.1241484. Rogers, L.L. 1987. Effects of food supply and kinship on social behavior, movements, and population growth of black bears in northeastern Minnesota. Wildlife Monographs 97:1­72. Roseberry, J.L. and A. Woolf. 1991. A comparative evaluation of techniques for analyzing white-tailed deer harvest data. Wildlife Monographs 117. Telesco, D. 2013. Summary of state and provincial status reports. Pages 9­15 in Proceedings of the 21st Eastern Black Bear Workshop, 28 April­1 May 2013, Millenocket, Maine. Tilton, M.K. 2005. Evaluating the effectiveness of population reconstruction for black bear (Ursus americanus) and white-tailed deer (Odocoileus virginianus) population management. Master's Thesis. Virginia Polytechnic Institute and State University, Blacksburg. Warburton, G.S., R.C. Maddrey, and D.W. Rowe. 1993. Characteristics of black bear mortality on the coastal plain of North Carolina. Proceedings of the Annual Conference of the Southeastern Association of Fish and Wildlife Agencies 47:276­286. Willey, C.H. 1974. Aging black bears from first premolar tooth sections. Journal of Wildlife Management 38:97­100. Wooding, J.B. and J.R. Brady. 1987. Black bear road kills in Florida. Proceedings of the Annual Conference of the Southeastern Association of Fish and Wildlife Agencies 41:438­442. ------, and T.S. Hardisky. 1994. Home range, habitat use, and mortality of black bears in north-central Florida. International Conference on Bear Research and Management 9:349­356.
2017 JSAFWA

AR Little, A Hammond, JA Martin

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