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Morphometry of moose antlers in central British Columbia.

ABSTRACT: We analyzed the morphometry of 1,965 sets of antlers from hunter-harvested moose (Alces alces andersoni) taken in the central interior of British Columbia. We describe the variation and age-related changes in antler and brow palm form, number of points on both main and brow palms, maximum spread, height and width of palmations, distance between innermost points on the brow palms, and shaft circumference. Architecturally, 25% were cervicorn pole type (PT); 75% were palmicorn with 67% split palm (SP) and 8% full palm (FP). palmicorn antlers were most common in all age classes. Cervicorn antlers were most common in younger moose (1.5-3.5 years), and rare in moose >4.5 years. Of all antlers collected, 30% had forked brows and 12% had palmated brows. Forked brow palms increased with age; they occurred in 10% of moose 1.5 years old and 40-50% of moose >4.5 years old. The frequency of palmated brow palms increased quickly from 1.5 (2.5%) to 5.5 years (25%), peaked at 13.5 years (40%), before declining in later years. The number of points generally increased from 1.5-7.5 years, and remained stable thereafter. Maximum spread and shaft circumference generally increased from 1.5-13.5 years and decreased thereafter. Maximum antler height and width of main palms increased from 1.5-9.5 years; the first remained stable and the latter declined thereafter. Distance between the inner most points on the brow palms narrowed from 1.5-4.5 years, remained constant to 11.5 years, and then widened thereafter. Antler point counts were the most variable, whereas shaft circumference was the least variable character.

Key words: Alces alces, brow palm, full palm, main palm, morphometrics, pole type, split palm, sociobiology.

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Antlers are physiologically and behaviorally significant to members of the Cervidae, first developing as perennial, but later as deciduous protuberances of the skull (Bubenik 1982). Antlers appear to be luxury appendages that grow on males (and some females) only when other nutritional needs are satisfied (Heffelfinger 2006). The diversity of antler shapes and sizes provides convincing evidence that multiple factors were involved in shaping antlers over time - if antlers served only one purpose, then a single antler shape should have prevailed (Heffelfinger 2006).

Antlers are important in sparring and for defense, parading reproductive fitness, condition, and genetic superiority (Bubenik 1982, Heffelfinger 2006), to deflect and amplify sound (Bubenik and Bubenik 2008), and in thermoregulation (Stonehouse 1968). Bubenik et al. (1978) described a pattern of change in antler architecture and complexity relative to design, shape, and size that mirrored 3 life stages described by Gaillard et al. (2000) as juvenile, prime, and a senescent stage in seniors.

The growth and architecture of antler types varies among individuals of a species and between geographically distinct populations, and has been thoroughly described for moose (Alces alces) populations in North America (Cringan 1955, Timmennann 1971, Bubenik 1973, Bubenik 1982, Child 1982, Van Ballenberghe 1982, Gasaway et al. 1987) and Fennoscandia (Solberg and Saether 1993a, Engan 2001, Nygrdn et al. 2007). Antler size is influenced by age, genetic factors, health status, and nutrition (Hibler and Adcock 1971, Wolf 1980, Hannel 1983, Ullrey 1982). For example, Ullrey (1982) indicated that dietary energy restrictions reduce antler volume, shaft diameter, main shaft length, and number of shaft points in 1.5-year old white-tailed deer (Odocoileus virginianus). Therefore, understanding variation in antler types and morphometry in moose populations helps determine evolutionary history, sub-speciation, population fitness, and the influence of climatic conditions and habitat quality on antler growth. We describe the age- related morphometry of antler forms and changes in antler architectures of moose (A. a. andersoni) from central interior British Columbia.

STUDY AREA

The Omineca sub-region of the central interior is approximately 122,500 [km.sup.2] in total area representing ~13% of the total land mass of British Columbia (Fig. 1). Rugged mountainous terrain with deeply incised valleys is typical on the northern and eastern sides (Child 1992); in contrast, the terrain is fiat to rolling with hundreds of small lakes and wetlands in the southern and western areas (Heard et al. 1997). The sub-region contains extensive areas of important moose habitat in the sub-boreal ecotype. This ecotype is a comparatively homogeneous unit, located on an extensive drumlinized till plateau surrounding periglacial lake deposits and dissected by many rivers, lakes, and wetlands. Dominant tree species are lodgepole pine (Pinus contorta), white spruce (Picea glauca), and subalpine fir (Abies lasiocarpa). Fires, logging, and insect outbreaks have had major impacts on the forests. Extensive 80-100 year old pine stands were typical of the area during the period in which antlers were collected, and were the result of historical widespread forest fires followed by decades of fire suppression (Child 1992). Clear-cuts created mostly since the 1960s are common throughout the area. Forest succession is characterized by an early shrub stage of 10-25 year duration, and many shrub species are important foods of moose (Heard et al. 1997).

[FIGURE 1 OMITTED]

The climate is generally wet and cool, with precipitation evenly distributed throughout the year. Mean daily average temperature in the southern portion of the Omineca at Prince George is 4.0[degrees] C, ranging from a monthly mean of- 9.6[degrees] C in January to 15.5[degrees] C in July; the mean annual precipitation is 600.8 mm, with 216 cm as snow. In contrast, to the west at Fort Saint James the mean daily average temperature is 3.0[degrees] C, ranging from a monthly mean of- 11.3[degrees] C in January and 15.3[degrees] C in July; mean annual precipitation is 487 mm, with 192 cm as snow (Environment Canada 2010).

Annual harvest of moose has ranged from 946-1691 animals, averaging of 1340 [+ or -] 44 (SD) over 19 years of record. The moose population is considered stable and below carrying capacity; intraspecific competition does not limit per capita food consumption (Heard et al. 1997).

METHODS

From 1982-1989, successful limited entry hunters (LEH, selected by lottery) in central British Columbia were required to submit moose antlers for inspection to study age-related growth and developmental characteristics (Child and Aitken 1989); non-LEH hunters (those not selected by lottery) voluntarily submitted antlers for inspection (Hatter and Child 1992). On each set of antlers the following were measured by one Ministry of Environment technician: antler form - either full palm (FP), split palm (SP), or pole type (PT; Fig. 2), brow palm form (palm, fork, or unclassified palm), and numbers of points on each antler, main palm, and brow form according to Bubenik (1982). An antler tine is defined by regulation (British Columbia Ministry of Environment, 2008-2009 Hunting Regulations) to be a branch of an antler longer than its breadth, at least 2.5 cm in length, and is also called a point (Fig. 3). Number of points on each main palm was calculated to be the difference between the number of points on each antler and the number of points on the corresponding brow. Additionally, maximum spread, maximum antler height (left and right sides), maximum palm width (left and right sides), shaft circumference (left and right sides), and distance between the in nermost brow points were measured to the nearest mm (Fig. 4).

Incisor teeth were collected by hunters and submired to the Ministry of Environment in Victoria, British Columbia. Tooth samples were analyzed by 2 Ministry of Environment technicians. Age was determined by counts of cementum annuli (Sergeant and Pimlott 1969) and stated as calendar age (e.g., 1.5 years).

[FIGURE 2 OMITTED]

[FIGURE 3 OMITTED]

We plotted frequency distributions for all variables in order to identify outliers. We then examined the records for each outlier and deleted those records that were clearly erroneous due to typographical errors; i.e., where measurements were in error by orders of magnitude or errors in transposition of data. After deletions, 1,965 records were available for analysis; we pooled all available data to describe antler morphometries by age. The effects of year and area of harvest on antler morphometrics in the same population are being investigated separately.

[FIGURE 4 OMITTED]

Antlers of SP and FP were tabulated as palmicorn type and antlers of PT were tabulated as cervicorn type (sensu Bubenik 1997). Antler form was tabulated for the entire sample; proportional changes of each form were plotted against age. Similarly, the form of brow palm was tabulated for the entire sample; proportional changes in brow palm were plotted against age.

We report the range, mean, and standard deviation (SD) for each variable (i.e., point counts, maximum spread, left and right maximum palm height, left and right maximum palm width, left and right shaft circumference, and distance between the inner most brow points). Paired sample t-tests (P = 0.05) were used to compare the variables from the left and right sides of each set of antlers. Sample sizes for age-specific means are in Table 1.

Left and right antlers in moose are generally symmetrical (Solberg and Saether 1993b, Bowyer et al. 2001). Therefore, we arbitrarily chose to plot only the forms and variables for the left antler. Changes in age-specific means [+ or -] 1 SD for each variable on the left side of the antlers were plotted to demonstrate changes in antler architectures with age.

Correlations between all of the variables were determined in order to show relationships between the various architectural features. Coefficients of Variation (CV) were calculated for each variable to compare variation amongst all variables.

RESULTS

Age Distribution

The mean age of moose was 4.1 [+ or -] 2.7 (SD) years (n = 1,686); age ranged from 1.519.5 years (Fig. 5). Since only 2 moose >14.5 years were inspected, we combined the 14.5 (n = 8), 15.5 (n = 1), and 19.5 (n = 1) year old moose into a single [greater than or equal to]14.5 year old group. Yearling bulls might be under-represented in the sample because of the voluntary requirement by non-LEH hunters to submit antlers for inspection (Hatter 1999).

Antler Form

Antler form was recorded for 1,597 sets of antlers; 75% were palmicorn type (67% SP type, 8% FP type) and 25% were cervicom type (PT). Palmicorn antlers were most common in all age classes except yearlings. The majority ofpalmicorn antlers in each age class were SP type, whereas < 10% in each age class were FP type (Fig. 6). Cervicom (PT) antlers were the most common type in yearling moose (65%) and decreased in abundance to <10% in moose >3.5 years old.

[FIGURE 5 OMITTED]

Brow Palm Form

Brow palm form was recorded on 863 left antlers and 811 right antlers of the 1,965 antlers examined; palmation occurred on 13.1% and 12.4% of the left and right sides, respectively. Forked architectures were about twice as common as palmations; 30.8 % (n = 605) on the left and 28.9% (n = 567) on the right side. The remainder was unclassified, being neither forked nor palmated. The frequency of palmated brow palms increased linearly to approximately 25% at 5.5 years, and continued to increase at a slower rate to about 35% at 13.5 years, before decreasing to 10% thereafter. The frequency of forked brows also increased linearly to approximately 45% at 5.5 years, remaining relatively constant to 13.5 years, before increasing to 60% thereafter (Fig. 7).

[FIGURE 6 OMITTED]

Number of Points on Antlers

The number of points on the left side

ranged from 0-18, averaging 5.90 [+ or -] 2.62 (SD) (n = 1,924; points on the right side ranged from 1-15, averaging 5.81 [+ or -] 2.49 (SD) (n = 1,913). There were more points (t= 3.011, df = 1,906, P = 0.003) on the left (mean = 5.90 [+ or -] 2.63, n = 1,907) than right side (mean 5.81 [+ or -] 2.49, n = 1907), although the number of points on the left correlated (r = 0.866, n = 1,907, P<0.001) with the number on the right side. Generally, the number of antler points on both sides increased from 1.5-7.5 years, then remained relatively stable thereafter (Fig. 8).

[FIGURE 7 OMITTED]

Number of Points on Main Palms

The number of points on the left main palm ranged from 1-13, averaging 4.23 [+ or -] 2.01 points (SD) (n = 1,182); similarly, points on the right main palm ranged from 1-14, averaging 4.17 [+ or -] 1.89 (SD) (n = 1,175). There was no difference (t = 1.797, df= 1,138, P = 0.073) between the numbers of points on the left (mean = 4.24 [+ or -] 2.02, n = 1,139) and right main palms (mean = 4.18 4- 1.90, n = 1,139); the number of points on paired left and right main palms were correlated (r = 0.798, n = 1,139, P<0.001). Generally, the number of points on both palms increased from 1.5-7.5 years, then remained relatively constant thereafter (Fig. 8).

Number of Points on Brow Palms

The number of points on the left brow palm ranged from 0-7, averaging 1.75 [+ or -] 0.88 (SD) (n = 1,188); 0.3% had no measurable points, 46.7% were single points (spikes), 36.4% were 2 points (forks), and 16.7% had >3 points. On the right, points ranged from 0-8, averaging 1.72 [+ or -] 0.87 (SD) (n = 1,184); 0.1% had no measureable points, 48.2% were spikes, 36.5% were forks, and 15.2% had >3 points. There was no difference (t =1.744, df= 1146, P = 0.081) between the number of points on the right (mean = 1.73 [+ or -] 0.87, n = 1,147) and left brow palms (mean = 1.76 [+ or -] 0.88, n = 1,147); the number of points on the left and right brows were correlated (r = 0.742, n = 1,147, P<0.001). Generally, the number of points on both brow palms increased from 1.5-7.5 years, and remained relatively constant thereafter (Fig. 8).

Maximum Spread of Antlers

The maximum spread of 1,780 sets of antlers ranged from 322-1,613 mm, averaging 858 [+ or -] 204 (SD) mm. Maximum spread generally increased annually with age (Fig. 9).

[FIGURE 8 OMITTED]

[FIGURE 9 OMITTED]

Maximum Height of Antlers

The maximum antler height ranged from 49-1,194 mm. The mean maximum height on the left (519 [+ or -] 196 mm, n = 925) and right side (mean = 507 [+ or -] 192, n = 817) were similar. The maximum height of the left side (mean = 512 [+ or -] 188 mm, n =798) was not different (t = 1.858, df= 797, P = 0.063) from the right side (mean = 508 -4- 192 mm, n = 798) on each set of paired antlers; the height on the left was positively correlated (r = 0.950, n = 798, P<0.001) with height on the right side. Maximum height of both sides generally increased from 1.5-9.5 years, and remained relatively unchanged thereafter (Fig. 9).

Maximum Width of the Main Palm

The maximum width of the main palm ranged from 12-436 mm. Palm widths on the left (mean = 163 [+ or -] 68 mm, n = 1,359) were similar to those on the right side (mean = 162 [+ or -] 66, n = 1,357). The width of the main palm on the" left (mean = 163 [+ or -] 68 mm) was not different (t =l.111, df= 1336, P = 0.267) from the width on the right (mean = 162 [+ or -] 66 ram) in paired sets of antlers (n = 1337); width of the main palm on the left was positively cor related (r = 0.889, n = 1,337, P < 0.001) with width on the right side. Palm width of both sides generally increased with age from 1.5-9.5 years, and declined thereafter (Fig. 9).

Circumference of Antler Shaft

The shaft circumference of antlers ranged from 55-281 mm. Shaft circumference on the left side (mean = 147 [+ or -] 26 ram, n = 1,885) was similar to that on the right (mean = 147 [+ or -] 27, n = 1,819). There was no difference (t = 0.596, df= 1,805, P = 0.551) in shaft circumference on the left (mean = 147 [+ or -] 26 ram) and right sides (mean = 147 [+ or -] 26 mm) for paired sets of antlers (n = 1,806); shaft circumference on the left and right sides were positively correlated (r = 0.913, n = 1,806, P<0.001) for paired sets of antlers. Shaft circumference on both sides slowly increased with age (Fig. 10).

Distance between Innermost Points on Brow Palms

The distance between the innermost points on the brow ranged from 102-800 mm, averaging 375 [+ or -] 88 (SD) mm (n = 1,519). Average distance between the brow points narrowed from 417 mm at 1.5 year to 375 mm at 3.5 years. This distance remained relatively constant at ~350 mm from 4.5-11.5 years, then widened to >400 mm thereafter (Fig. 10).

[FIGURE 10 OMITTED]

Correlations between Antler Variables

Correlations between each variable on each side of a set of paired antlers (Table 1) were significant (P<0.001). Highest correlation coefficients (r) were found for antler height (r = 0.950) and shaft circumference (r = 0.914). Maximum spread, often the measurement of choice by hunters, was highly correlated with all other measures. The distance between innermost points on the brow palms and all other variables had the lowest correlation coefficients.

Variability in Antler Measurements

The least variable measure was shaft circumference (CV = 18% for both left and right sides); the most variable was number of points on the brow palms (CV = 51% for both left and right sides). Generally, the number of points had most variability (Table 2).

DISCUSSION

We found that form and morphometrics of antlers of bull moose changed with age in the central interior of British Columbia. These changes progressed through the juvenile and prime stages, ended in the senior/ senescent stage (Gaillard et al. 2000), and were similar to those described for moose in North America (Timmermann 1971, Bubenik et al. 1978, Van Ballenberghe 1982, Erling et al. 1987, Gasaway et al. 1987). Prime moose (approximately 5 - 12 years) have near maximal antler size and antler growth plateaus at this stage (Gasaway et al. 1987). Antler size in juveniles (approximately 1-4 years) rapidly increases toward full development, whereas antlers of seniors (> 12 years) gradually regress from full development. The mean maximum spread of antlers from our sample was similar to that of A. a. andersoni and A. a. americana, but smaller than that of A. a. gigas (Gasaway et al. 1987).

Gasaway et al. (1987) found that both palmicorn and cervicorn (pole type) antler forms occur throughout North America with palmicorn antlers being the predominant form for moose [greater than or equal to] 2 years old; our findings are similar. Furthermore, Bubenik (1997) subdivided palmicorn into full palm (shell type) and split palm (butterfly type) forms; both were documented in the Omineca. Split palm antlers were the most common type in all age classes of moose [greater than or equal to]2.5 years old, whereas full palm antlers were infrequent in most age classes. We were unable to compare the variation of SP and FP types across North America. The proportion (65%) of yearlings in the Omineca with cervicorn antlers was higher than that documented throughout North America (30-40%; Gasaway et al. 1987). It is unknown whether this higher percentage reflects difference in range condition (Nygr6n et al. 2007) and hunting regulations between the Omineca and other jurisdictions, and/or other factors.

The pattern of antler architecture and their increasing complexity in design, shape, and size in the central interior of British Columbia was similar to that described in other regions of North America (Timmermann 1971, Bubenik et al. 1978, Gasaway et al. 1987). There was, however, a great deal of variation in antler size and shape among moose of the same age, and between males of different age classes. Given that genetics, location (e.g., range quality), and other factors influence the growth and final design of antlers (Hundertmark and Bowyer 2004), variation in antler morphometry is not surprising. Knowledge of the age-related growth and development of antlers is important because harvest regulations increasingly define "legal" bulls by form and growth characteristics (Child and Aitken 1989, Hatter 1999, Demarchi and Hartwig 2008). It follows then that field collection and measurement of moose antlers is needed to best describe and understand standards, variation, and change amongst managed populations, especially where and if antler-based hunting regulations are planned or practiced (Child et al. 2010).

ACKNOWLEDGEMENTS

We thank Scan Barry for his meticulous attention to detail in measuring and recording the forms of all inspected antlers and to Ken Fujino and Sean Barry of the Wildlife Branch who prepared and aged the tooth samples. A special thanks to Gerry Kuzyk for release of the antler data records and to the many hunters who willingly submitted the antlers for inspection. We also thank the anonymous reviewers for their comments on an earlier draft of the manuscript.

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Kenneth N. Child (1), Daniel A. Aitken (2), and Roy V. Rea (3)

(1) 6372 Comell Place, Prince George, British Columbia V2N 2N7, Canada; (2) College of New Caledonia, 3330 22nd Avenue, Prince George, British Columbia V2N 1 P8, Canada; (3) Natural Resources and Environmental Studies Institute, University of Northern British Columbia, 3333 University Way, Prince George, British Columbia V2N 479, Canada.
Table 1. Sample sizes for antler form, brow form, and the 8 variables
examined on the left antler. AF = antler form, BF = brow form, NPL =
number of points on left antler, MPL= main palm points left antler,
BPL=brow points left antler, MS =maximum spread, MHL= maximum height
left antler, SCL = shaft circumference left antler, PWL = palm width
left antler, and DIBP = distance between innermost points on the brow
palm.

         Age     AF     BF    NPL    MPL    BPL     MS    MHL

          1.5    309     47    360    206    207    306    145
          2.5    290    111    346    232    233    323    162
          3.5    268    156    312    213    213    295    161
          4.5    167    116    197    133    133    190    107
          5.5    103     85    122     74     74    118     58
          6.5     84     71     94     66     67     92     48
          7.5     51     46     70     42     43     70     45
          8.5     45     34     49     28     28     47     27
          9.5     32     26     34     21     22     33     15
         10.5     23     21     26     16     16     24     23
         11.5     17     14     18     11     11     17      7
         12.5     11      9     12      6      6     11      4
         13.5     11     10     11     10     10     11      6
        14.5+      8      7     10      6      6     10      6

   Total aged   1419    753   1661   1064   1069   1547    814

Recorded, but    178    110    235    118    119    233    111
     not aged

 Not recorded    368   1102     41    783    777    185   1040

 Total Sample   1965   1965   1965   1965   1965   1965   1965

         Age    SCL    PWL    DIBP

          1.5    345    221    217
          2.5    343    249    266
          3.5    311    238    261
          4.5    191    152    169
          5.5    120     80    105
          6.5     93     78     86
          7.5     71     53     67
          8.5     49     41     45
          9.5     35     26     26
         10.5     26     20     22
         11.5     18     14     15
         12.5     11      7     11
         13.5     11     10      9
        14.5+     10      7     10

   Total aged   1634   1196   1309

Recorded, but    251    163    210
     not aged

 Not recorded     80    606    446

 Total Sample   1965   1965   1965

Table 2. Pearson correlation coefficients between all measurements for
moose antlers. All correlations were significant at P<0.001. Sample
sizes are shown below the correlation coefficient.

        NPL      NPR      MPL      MPR      BPL      BPR       MS

 NPL     --     0.866    0.953    0.793    0.715    0.651     0.77
        1924     1907     1182     1175     1182     1178     1767

 NPR   0.866      --     0.808    0.947    0.649    0.714    0.767
        1907     1913     1170     1175     1171     1175     1762

 MPL   0.953    0.808      --     0.798     0A68    0.506    0.719
        1182     1170     1182     1139     1182     1142     1093

 MPR   0.793    0.947    0.798      --     0.494    0.452    0.699
        1175     1175     1139     1175     1139     1175     1094

 BPL   0.715    0.649    0.468    0.494      --     0.742    0.561
        1182     1171     1182     1139     1188     1147     1097

 BPR   0.651    0.714    0.506    0.452    0.742      --     0.572
        1178     1175     1142     1175     1147     1184     1102

  MS    0.77    0.767    0.719    0.699    0.561    0.572      --
        1767     1762     1093     1094     1097     1102     1780

 MHL   0.764     0.75    0.739     0.72    0.595    0.596    0.806
        917      911      649      644      652      648      855

 MHR    0.74    0.762    0.709    0.748    0.593    0.598    0.805
        809      807      619      618      621      622      756

 SCL   0.721    0.702    0.688    0.652    0.553    0.562    0.765
        1873     1859     1171     1162     1177     1171     1749

 SCR   0.708    0.724    0.661    0.661     0.54    0.559    0.769
        1903     1803     1163     1165     1167     1173     1686

 PWL   0.802    0.773    0.762    0.741    0.608    0.605     0.73
        1351     1340     1047     1040     1052     1047     1272

 PWR    0.76    0.811    0.723    0.778    0.593    0.604    0.724
        1347     1346     1041     1045     1045     1052     1276
DIBP   -0.351   -0.361   -0.279   -0.318   -0.405   -0.377   -0.162
        1513     1510     941      947      944      953      1498

        MHL      MHR     SCL      SCR      PWL      PWR      DIBP

 NPL   0.764    0.74    0.721    0.708    0.802     0.76    -0.351
        917      809     1873     1803     1351     1347     1513

 NPR    0.75    0.762   0.702    0.724    0.773    0.811    -0.361
        911      807     1859     1803     1340     1346     1510

 MPL   0.739    0.709   0.688    0.661    0.762    0.723    -0.279
        649      619     1171     1163     1047     1041     941

 MPR    0.72    0.748   0.652    0.662    0.741    0.778    -0.318
        644      618     1162     1165     1040     1045     947

 BPL   0.595    0.593   0.553     0.54    0.608    0.593    -0.405
        652      621     1177     1167     1052     1045     944

 BPR   0.596    0.598   0.562    0.559    0.605    0.604    -0.377
        648      622     1171     1173     1047     1052     953

  MS   0.806    0.805   0.765    0.769     0.73    0.724    -0.162
        855      756     1749     1686     1272     1276     1498

 MHL     --     0.95    0.782    0.788    0.762    0.731    -0.271
        925      798     913      905      753      747      756

 MHR    0.95     --     0.752     0.78    0.776     0.76    -0.26
        798      817     808      809      658      660      663

 SCL   0.782    0.752     --     0.913    0.694    0.692    -0.262
        913      808     1885     1806     1349     1340     1507

 SCR   0.788    0.78    0.913      --     0.701    0.715    -0.259
        905      809     1806     1819     1339     1347     1455

 PWL   0.762    0.776   0.694    0.701      --     0.889    -0.314
        753      658     1349     1339     1359     1337     1097

 PWR   0.731    0.76    0.692    0.716    0.889      --     -0.306
        747      660     1340     1347     1337     1357     1102

DIBP   -0.271   -0.26   -0.262   -0.259   -0.314   -0.306     -
        756      663     1507     1455     1097     1102     1519

Note: NPL = nmnber of points on left antler, NPR = number of points on
right antler, MPL = main palm points left antler, MPR =main palm points
right antler, BPL = brow points left antler, BPR = brow points right
antler, MS = maximum spread, NM = maximum height left antler, MHR =
maximum height right antler, SCL =shaft circumference left antler, SCR
= shaft cir cumference right antler, PWL = palm width left antler, PWR
= palm width right antler, and DIBP = distance between innermost points
on the brow palm.

Table 3. Coefficient of variation for each antler
variable.

Antler Measurement           Coefficient of    n
                             Variation (%)

Shaft circumference left           18         1885

Shaft circumference right          18         1816

Distance between innermost         23         1519
points on brow palms

Maxinum. spread                    24         1780

Maximum height left antler         38          923

Maximum height right antler        38          816

Palm width right antler            41         1355

Palm width left antler             42         1359

Total number points right          43         1910
antler

Total number points left           44         1921
antler

Main palm points right             45         1173
antler

Main palm points left antler       48         1182

Brow points right antler           51         1182

Brow points left antler            51         1188
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Author:Child, Kenneth N.; Aitken, Daniel A.; Rea, Roy V.
Publication:Alces
Date:Jan 1, 2010
Words:5595
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