Estimating the age structure of a population of brushtail possums (Trichosurus vulpecula) by comparing tooth wear and cementum lines
Cheryl A. Lohr A , Tammy Esmaili A , Harriet Mills A and Roberta Bencini A B
+ Author Affiliations
- Author Affiliations
A School of Animal Biology, The University of Western Australia, M092, 35 Stirling Highway, Crawley, WA 6009, Australia.
B Corresponding author. Email: Roberta.Bencini@uwa.edu.au
Australian Mammalogy 33(1) 52-56 https://doi.org/10.1071/AM10054
Submitted: 14 December 2010 Accepted: 31 January 2011 Published: 23 March 2011
Abstract
We used cementum lines from a sample of possums to calibrate tooth wear patterns in free-ranging common brushtail possums (Trichosurus vulpecula) to estimate of the age structure of a wild population of the species living at the Perth Zoo, Western Australia. We assessed patterns of tooth wear and incremental cementum lines in teeth extracted from 40 possums via necropsy. Rank regression for non-parametric data revealed a weak relationship between the number of cementum lines per tooth (y), which was assumed to correspond to the age of the possums (in years), and tooth wear (males: age = 0.51x + 3.4, r2 = 0.098, n = 27; females: age = 1.17x + 0.35, r2 = 0.345, n = 45). We used these relationships and the tooth wear pattern of 149 live possums caught at Perth Zoo to develop an estimate of the age structure of the population. Most (63.1%) possums were between 4 and 6 years of age. Very few young (1–2 years) or old (6–8 years) possums were caught at Perth Zoo. These results yielded an approximate age distribution for possums within Perth Zoo and should be used with caution because the relationship between the number of cementum lines and tooth wear was weak.
References
Andrzejewski, R., and Liro, A. (1977). Effects of different kinds of feed on wear of the teeth in individuals of a field mouse population. Acta Theriologica 22, 393–395.Brockie, R. E., Bell, B. D., and White, A. J. (1981). Age structure and mortality of possum (Trichosurus vulpecula) populations from New Zealand. In ‘Proceedings of the First Symposium of Marsupials in New Zealand, Wellington, New Zealand’. pp. 63–86. (Dept of Zoology, Victoria University of Wellington: Wellington, NZ.)
Bureau of Meteorology (2007). Perth Metro. Australian Government Climate statistics for Australian locations. Australian Government.
Clout, M. N. (1982). Determination of age in the brushtail possum using sections from decalcified molar teeth. New Zealand Journal of Zoology 9, 405–408.
Cowan, P. E., and White, A. J. (1989). Evaluation of a tooth-wear age index for brushtail possums, Trichosurus vulpecula. Australian Wildlife Research 16, 321–322.
| Evaluation of a tooth-wear age index for brushtail possums, Trichosurus vulpecula.Crossref | GoogleScholarGoogle Scholar |
Coy, P. L., and Garshelis, D. L. (1992). Reconstructing reproductive histories of black bears from incremental layering in dental cementum. Canadian Journal of Zoology 70, 2150–2160.
| Reconstructing reproductive histories of black bears from incremental layering in dental cementum.Crossref | GoogleScholarGoogle Scholar |
Dunnet, G. M. (1964). A field study of local populations of the brushtailed possum Trichosurus vulpecula in eastern Australia. Proceedings of the Zoological Society of London 142, 665–695.
| A field study of local populations of the brushtailed possum Trichosurus vulpecula in eastern Australia.Crossref | GoogleScholarGoogle Scholar |
Gordon, G. (1991). Estimation of age of the koala, Phascolarctos cinereus (Marsupailia: Phascolarctidae) from tooth wear and growth. Australian Mammalogy 14, 5–12.
Grue, H., and Jensen, B. (1978). Review of the formation of incremental lines in tooth cementum of terrestrial mammals. Danish Review of Game Biology 11, 1–48.
Hamlin, K. L., Pac, D. F., Sime, C. A., DeSimone, R. M., and Dusek, G. L. (2000). Evaluating the accuracy of ages obtained by two methods for Montana ungulates. Journal of Wildlife Management 64, 441–449.
| Evaluating the accuracy of ages obtained by two methods for Montana ungulates.Crossref | GoogleScholarGoogle Scholar |
Harshyne, W. A., Diefenbach, D. R., Alt, G. L., and Matson, G. M. (1998). Analysis of error from cementum-annuli age estimates of known-age Pennsylvania black bears. Journal of Wildlife Management 62, 1281–1291.
| Analysis of error from cementum-annuli age estimates of known-age Pennsylvania black bears.Crossref | GoogleScholarGoogle Scholar |
Hetherington, C. A. (2007). Use of deslorelin to manage an urban population of brushtail possums (Trichosurus vulpecula). M.Sc. Thesis, The University of Western Australia, Perth.
Hillson, S. (1986). ‘Teeth.’ (Cambridge University Press: Cambridge.)
Kean, R. I. (1975). Growth of opossums (Trichosurus vulpecula) in the Orongorongo Valley, Wellington, New Zealand, 1953–61. New Zealand Journal of Zoology 2, 435–444.
| Growth of opossums (Trichosurus vulpecula) in the Orongorongo Valley, Wellington, New Zealand, 1953–61.Crossref | GoogleScholarGoogle Scholar |
Keay, J. A. (1995). Accuracy of cementum age assignments for black bears. California Fish and Game 81, 113–121.
Kingsmill, E. (1962). An investigation of criteria for estimating age in marsupials Trichosurus vulpecula Kerr and Perameles nasuta Geoffroy. Australian Journal of Zoology 10, 597–618.
| An investigation of criteria for estimating age in marsupials Trichosurus vulpecula Kerr and Perameles nasuta Geoffroy.Crossref | GoogleScholarGoogle Scholar |
Lohr, C. A., Mills, H., Robertson, H., and Bencini, R. (2009). Deslorelin implants control fertility in urban brushtail possums (Trichosurus vulpecula) without impacting negatively on their body condition index. Wildlife Research 36, 324–332.
| Deslorelin implants control fertility in urban brushtail possums (Trichosurus vulpecula) without impacting negatively on their body condition index.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXms1agur8%3D&md5=053e726a77acc0141e631e371b3a0152CAS |
Low, W. A., and Cowan, I. M. (1963). Age determination of deer by annular structure of dental cementum. Journal of Wildlife Management 27, 466–471.
| Age determination of deer by annular structure of dental cementum.Crossref | GoogleScholarGoogle Scholar |
Moffitt, S. A. (1998). Aging bison by the incremental cementum growth layer in teeth. Journal of Wildlife Management 62, 1276–1280.
| Aging bison by the incremental cementum growth layer in teeth.Crossref | GoogleScholarGoogle Scholar |
Pahl, L. I. (1987). Survival, age determination and population age structure of the common ringtail possum, Pseudocheirus peregrinus, in a Eucalyptus woodland and a Leptospermum thicket in southern Victoria. Australian Journal of Zoology 35, 625–639.
| Survival, age determination and population age structure of the common ringtail possum, Pseudocheirus peregrinus, in a Eucalyptus woodland and a Leptospermum thicket in southern Victoria.Crossref | GoogleScholarGoogle Scholar |
Pekelharing, C. J. (1970). Cementum deposition as an age indication in the brushtailed possum, Trichosurus vulpecula Kerr (Marsupailia). Australian Journal of Zoology 18, 71–76.
| Cementum deposition as an age indication in the brushtailed possum, Trichosurus vulpecula Kerr (Marsupailia).Crossref | GoogleScholarGoogle Scholar |
Rausch, R. L. (1967). Comparative development of the canine teeth in wild and captive bred black bears, Ursus americanus Pallas. Canadian Journal of Zoology 45, 465–471.
| Comparative development of the canine teeth in wild and captive bred black bears, Ursus americanus Pallas.Crossref | GoogleScholarGoogle Scholar | 1:STN:280:DyaF1c3nsFOlsg%3D%3D&md5=4fa4f4a48aac9ba2e07eb3790481545eCAS | 5588104PubMed |
Rodgers, L. L. (1978). Interpretation of cementum annuli in first pre-molars of bears. In ‘Proceedings of the Fourth Eastern Workshop on Black Bear Research and Management, University of Maine, Orono, Maine’. pp. 102–112. (Maine Department of Inland Fisheries and Wildlife: Greeneville, ME, USA).
Sauer, P. R., Free, S., and Browne, S. (1966). Age determination in black bears from canine tooth sections. New York Fish and Game Journal 13, 125–139.
Tan, P. (1999). Population parameters of two common brushtail possum, Trichosurus vulpecula (Kerr), populations. B.Sc.(Honours) Thesis, The University of Western Australia, Perth.
Winter, J. W. (1980). Tooth wear as an age index in a population of the brush-tailed possum, Trichosurus vulpecula (Kerr). Australian Wildlife Research 7, 359–363.
| Tooth wear as an age index in a population of the brush-tailed possum, Trichosurus vulpecula (Kerr).Crossref | GoogleScholarGoogle Scholar |
