Dormancy in Caladenia: a Bayesian approach to evaluating latency
Raymond L. Tremblay A H , Maria-Eglée Perez B , Matthew Larcombe C , Andrew Brown D , Joe Quarmby E , Doug Bickerton E , Garry French F and Andrew Bould GA Department of Biology, 100 Carr. 908, University of Puerto Rico, Humacao Campus, Humacao, Puerto Rico, 00791-4300, USA and Crest-Catec, Center for Applied Tropical Ecology and Conservation, PO Box 23341, University of Puerto Rico, Río Piedras, Puerto Rico, 00931-3341, USA.
B Department of Mathematics, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico, USA, 00931-3355. Crest-Catec, Center for Applied Tropical Ecology and Conservation, PO Box 23341, University of Puerto Rico, Río Piedras, Puerto Rico, 00931-3341, USA.
C Threatened Species Section, Department of Primary Industries and Water, GPO Box 44, Hobart, Tas. 7001, Australia.
D Species and Communities Branch, Department of Environment and Conservation, Locked Bag 104, Bentley Delivery Centre, WA 6983, Australia.
E Threatened Species Unit, Conservation Policy and Programs, Department for Environment and Heritage, GPO Box 1047, Adelaide, SA 5001, Australia.
F Parks Victoria, Yarra District, PO Box 568, Templestowe, Vic. 3106, Australia.
G 109 Western Boulevard, Raymond Island, Vic. 3880, Australia.
H Corresponding author. Email: raymond@hpcf.upr.edu
Australian Journal of Botany 57(4) 340-350 https://doi.org/10.1071/BT08163
Submitted: 30 August 2008 Accepted: 18 June 2009 Published: 29 July 2009
Abstract
Dormancy is common in many terrestrial orchids in southern Australia and other temperate environments. The difficulty for conservation and management when considering dormancy is ascertaining whether non-emergent plants are dormant or dead. Here we use a multi-state capture–recapture method, undertaken over several seasons, to determine the likelihood of a plant becoming dormant or dying following its annual emergent period and evaluate the frequency of the length of dormancy. We assess the transition probabilities from time series of varying lengths for the following nine terrestrial orchids in the genus Caladenia: C. amoena, C. argocalla, C. clavigera, C. elegans, C. graniticola, C. macroclavia, C. oenochila, C. rosella and C. valida from Victoria, South Australia and Western Australia. We used a Bayesian approach for estimating survivorship, dormancy and the likelihood of death from capture–recapture data. Considering all species together, the probability of surviving from one year to the next was ~86%, whereas the likelihood of observing an individual above ground in two consecutive years was ~74%. All species showed dormancy of predominantly 1 year, whereas dormancy of three or more years was extremely rare (<2%). The results have practical implications for conservation, in that (1) population sizes of Caladenia species are more easily estimated by being able to distinguish the likelihood of an unseen individual being dormant or dead, (2) population dynamics of individuals can be evaluated by using a 1–3-year dormancy period and (3) survey effort is not wasted on monitoring individuals that have not emerged for many years.
Acknowledgements
M. L. is funded by the Tasmanian Cross Regional NRM project to Implement Threatened Species Recovery Plans. J. Q. and D. B. give their appreciation to Deb Way, Kate Greenhill, Irene Thomas, Heather Bryant, David Kilpin, Cathy & Malcolm Houston, Peter McCauley, Rick Davies, Pam O’Malley, Rod Hawke, Ken & Barb Bayley and Thelma & Phil Bridle for their help, and to the Adelaide & Mount Lofty Ranges NRM Board, Northern & Yorke NRM Board and Natural Heritage Trust for funding.
Alexander HM,
Slade NA, Kettle WD
(1997) Application of mark–recapture models to estimation of the population size of plants. Ecology 78, 1230–1237.
Brooks SP, Gelman A
(1998) Alternative methods for monitoring convergence of iterative simulations. Journal of Computational and Graphical Statistics 7, 434–455.
| Crossref | GoogleScholarGoogle Scholar |
Brundrett MC
(2007) Scientific approaches to Australian temperate terrestrial orchid conservation. Australian Journal of Botany 55, 293–307.
| Crossref | GoogleScholarGoogle Scholar |
Calvo RN
(1990) Four-year growth and reproduction of Cyclopogon carnichoides (Orchidaceae) in South Florida. American Journal of Botany 77, 1378–1381.
| Crossref | GoogleScholarGoogle Scholar |
Coates F,
Lunt I, Tremblay RL
(2006) The effect of fire, rainfall, herbivory on population dynamics of a threatened terrestrial orchid from south-eastern Australia, Prasophyllum correctum D.L. and consequences for management. Biological Conservation 129, 59–69.
| Crossref | GoogleScholarGoogle Scholar |
Gregg KB, Kéry M
(2006) Comparison of size vs. life-sate classification in demographic models for the terrestrial orchid Cleistes bifaria. Biological Conservation 129, 50–58.
| Crossref | GoogleScholarGoogle Scholar |
Kéry M, Gregg KB
(2004) Demographic analysis of dormancy and survival in the terrestrial orchid Cypripedium reginae. Journal of Ecology 92, 686–695.
| Crossref | GoogleScholarGoogle Scholar |
Kéry M,
Gregg KB, Schaub M
(2005) Demographic estimation methods for plants with unobservable life-states. Oikos 108, 307–320.
| Crossref | GoogleScholarGoogle Scholar |
Kettle WD,
Alexander HM, Pittman GL
(2000) An 11-year ecological study of a rare prairie perennial (Asclepias meadii): implications for monitoring and management. American Midland Naturalist 144, 66–77.
| Crossref | GoogleScholarGoogle Scholar |
Kirkman LK,
Drew MB, Edwards D
(1998) Effects of experimental fire regimes on the population dynamics of Schwalbea Americana L. Plant Ecology 137, 115–137.
| Crossref | GoogleScholarGoogle Scholar |
Lesica P, Crone EE
(2007) Causes and consequences of prolonged dormancy for iteroparous geophyte, Silene spaldingii. Journal of Ecology 95, 1360–1369.
| Crossref | GoogleScholarGoogle Scholar |
Lesica P, Steele BM
(1994) Prolonged dormancy in vascular plants and implications for monitoring studies. Natural Areas Journal 14, 209–212.
Lunn DJ,
Thomas A,
Best N, Spiegelhalter D
(2000) WinBUGS; a Bayesian modelling framework: concepts, structure, and extensibility. Statistics and Computing 10, 325–337.
| Crossref | GoogleScholarGoogle Scholar |
Miller MT,
Allen GA, Antos JA
(2004) Dormancy and flowering in two mariposa lilies (Calochortus) with contrasting distribution patterns. Canadian Journal of Botany 82, 1790–1799.
| Crossref | GoogleScholarGoogle Scholar |
Morrow PA, Olfelt JP
(2003) Phoenix clones: recovery after long-term defoliation-induced dormancy. Ecology Letters 6, 119–125.
| Crossref | GoogleScholarGoogle Scholar |
Nicotra AB
(1999) Reproductive allocation and long-term costs of reproduction in Siparuna grandiflora, a dioecious neo-tropical shrub. Journal of Ecology 87, 138–149.
| Crossref | GoogleScholarGoogle Scholar |
Obeso JR
(2002) The costs of reproduction in plants. New Phytologist 155, 321–348.
| Crossref | GoogleScholarGoogle Scholar |
Petit S,
Jusaitis M, Bickerton D
(2009) Effect of pollen load, self-pollination, and plant size on seeds and germination in the endangered pink-lipped spider orchid, Caladenia behrii. Australian Journal of Botany 57, 307–314.
Pfeifer M,
Wiegand K,
Heinrich W, Jetschke G
(2006) Long-term demographic fluctuations in an orchid species driven by weather: implications for conservation planning. Journal of Applied Ecology 43, 313–324.
| Crossref | GoogleScholarGoogle Scholar |
Primack RB, Stacy E
(1998) Costs of reproduction in the pink lady’s slipper orchid (Cypripedium acaule): an eleven-year experimental study of three populations. American Journal of Botany 85, 1672–1679.
| Crossref | GoogleScholarGoogle Scholar |
Reed JM,
Mill LS,
Dunning JB,
Menges ES,
McKelvey KS,
Frye R,
Beissinger SR,
Anstett M-C, Miller P
(2002) Emerging issues in population viability analysis. Conservation Biology 16, 7–19.
| Crossref | GoogleScholarGoogle Scholar |
Schemske DW,
Husband BC,
Ruckelshaus MH,
Goodwillie C,
Parker IM, Bishop JG
(1994) Evaluating approaches to the conservation of rare and endangered plants. Ecology 75, 584–606.
| Crossref | GoogleScholarGoogle Scholar |
Shefferson RP
(2006) Survival costs of adult dormancy and the confounding influence of size in lady’s slipper orchids, genus Cypripedium. Oikos 115, 253–262.
| Crossref | GoogleScholarGoogle Scholar |
Shefferson RP, Simms EL
(2007) Costs and benefits of fruiting to future reproduction in two dormancy prone orchids. Journal of Ecology 95, 865–875.
| Crossref | GoogleScholarGoogle Scholar |
Shefferson RP, Tali K
(2007) Dormancy is associated with decrease adult survival in burnt orchid, Neotinea ustulata. Journal of Ecology 95, 217–225.
| Crossref | GoogleScholarGoogle Scholar |
Shefferson RP,
Proper J,
Beissenger SR, Simms EL
(2003) Life history trade-offs in a rare orchid: The costs of flowering, dormancy and sprouting. Ecology 84, 1199–1206.
| Crossref | GoogleScholarGoogle Scholar |
Shefferson RP,
Kull T, Tali K
(2005) Adult whole-plant dormancy induced by stress in long-lived orchids. Ecology 86, 3099–3104.
| Crossref | GoogleScholarGoogle Scholar |
Slade NA,
Alexander HM, Kettle WD
(2003) Estimation of population size and probabilities of survival and detection in Mead’s milkweed. Ecology 84, 791–797.
| Crossref | GoogleScholarGoogle Scholar |
Smith BJ
(2007) Boa: an R package for MCMC output convergence, assessment and posterior inference. Journal of Statistical Software 21, 1–37.
Spiegelhalter DJ,
Best NG,
Carlin BP, Van der Linde A
(2002) Bayesian measures of model complexity and fit (with discussion). Journal of the Royal Statistical Society. Series B. Methodological 64, 583–639.
| Crossref | GoogleScholarGoogle Scholar |
Tobe K, Gao Y
(2007) Seed germination and seedling emergence of herbs in sand. Australian Journal of Botany 55, 55–62.
| Crossref | GoogleScholarGoogle Scholar |
Tremblay RL
(2006) The effect of population structure, plant size, herbivory and reproductive potential on effective population size in a temperate epiphytic orchid, Sarcochilus australis. Cunninghamia 9, 529–535.
Tremblay RL, Ackerman JD
(2001) Gene flow and effective population size in Lepanthes (Orchidaceae): a case for genetic drift. Biological Journal of the Linnean Society. Linnean Society of London 72, 47–62.
| Crossref | GoogleScholarGoogle Scholar |
Tremblay RL,
Ackerman JD,
Zimmerman JK, Calvo RN
(2005) A review of variation in sexual reproduction in orchids and its evolutionary consequences: a spasmodic journey to diversification. Biological Journal of the Linnean Society. Linnean Society of London 84, 1–54.
| Crossref | GoogleScholarGoogle Scholar |
Waite S, Farrell L
(1998) Population biology of the rare military orchid (Orchis militaris L.) at an established site in Suffolk, England. Botanical Journal of the Linnean Society 126, 109–121.
Zotz G, Schmidt G
(2006) Population decline in the epiphytic orchid Aspasia principissa. Biological Conservation 129, 82–90.
| Crossref | GoogleScholarGoogle Scholar |