Journal of Ornithology

, Volume 152, Supplement 2, pp 597–604

Investigating the population dynamics of California spotted owls without marked individuals

  • D. I. MacKenzie
  • M. E. Seamans
  • R. J. Gutiérrez
  • J. D. Nichols
EURING Proceedings


Understanding population dynamics is of great interest in many different contexts. Traditionally, population dynamics have often been considered in terms of individual-based demographic parameters (e.g., abundance, survival, and reproductive rates), estimation of which generally requires information from marked individuals. Alternatively, in some situations, it may be appropriate to consider population dynamics at a landscape level where the focus is shifted from numbers of individuals to the status of the population at places on the landscape. One consequence of doing so is that information from marked individuals is no longer required. Recently developed methods allow the estimation of landscape-level population vital rates in the realistic situation where the current status of the population might be misclassified via field methods (e.g., because of imperfect detection). Here, we consider the case of the California spotted owl (Strix occidentalis occidentalis) at the Eldorado study area in central Sierra Nevada, California, USA, where interest is in the occupancy rate of potential nesting territories, and in whether owls in an occupied territory successfully reproduced each year during 1997–2004. We analyzed the data using multistate occupancy models and found no evidence of annual variation in dynamic occupancy probabilities. There was strong evidence of annual variation in successful reproduction, with the pattern of variation being different depending on whether there was successful reproduction in the territory in the previous year. Of the three environmental variables considered, the Southern Oscillation Index appeared to be most important and explained some of the annual variation in reproduction probabilities.


California spotted owl Detection Multistate Occupancy models 


  1. Anthony RG, Forsman ED, Franklin AB, Anderson DR, Burnham KP, White GC, Schwarz CJ, Nichols JD, Hines JE, Olson GS, Ackers SH, Andrews LS, Biswell BL, Carlson PC, Diller LV, Dugger KM, Fehring KE, Fleming TL, Gerhardt RP, Gremel SA, Gutierrez RJ, Happe PJ, Herter DR, Higley JM, Horn RB, Irwin LL, Loschl PJ, Reid JA, Sovern SG (2006) Status and trends in demography of northern spotted owls, 1985–2003. Wildl Monogr 163:1–48Google Scholar
  2. Blakesley JA, Anderson DR, Noon BR (2006) Breeding dispersal in the California spotted owl. Condor 108:71–81CrossRefGoogle Scholar
  3. Conn PB, Cooch EG (2009) Multistate capture-recapture analysis under imperfect state observation: application to disease models. J Appl Ecol 46:486–492CrossRefGoogle Scholar
  4. Franklin AB, Gutiérrez RJ, Nichols JD, Seamans ME, White GC, Zimmerman GS, Hines JE, Munton TE, LaHaye WS, Blakesley JA, Steger GN, Noon BR, Shaw DWH, Keane JJ, McDonald TL, Britting S (2004) Population dynamics of the California spotted owl (Strix occidentalis occidentalis): a meta-analysis. Am Ornithol Union Monogr No 54:1–54Google Scholar
  5. Gaillard J-M, Festa-Bianchet M, Yoccoz NG, Loison A, Toïgo C (2000) Temporal variation in fitness components and population dynamics of large herbivores. Annu Rev Ecol Syst 31:367–393CrossRefGoogle Scholar
  6. Kendall WL, Hines JE, Nichols JD (2003) Adjusting multi-state capture-recapture models for misclassification bias: manatee breeding proportions. Ecology 84:1058–1066CrossRefGoogle Scholar
  7. MacKenzie DI, Nichols JD, Hines JE, Knutson MG, Franklin AD (2003) Estimating site occupancy, colonization and local extinction when a species is detected imperfectly. Ecology 84:2200–2207CrossRefGoogle Scholar
  8. MacKenzie DI, Nichols JD, Royle JA, Pollock KH, Bailey LL, Hines JE (2006) Occupancy estimation and modeling: inferring patterns and dynamics of species occurrence. Elsevier, San DiegoGoogle Scholar
  9. MacKenzie DI, Nichols JD, Seamans ME, Gutiérrez RJ (2009) Modeling species occurrence dynamics with multiple states and imperfect detection. Ecology 90:823–835PubMedCrossRefGoogle Scholar
  10. Nichols JD, Kendall WL, Hines JE, Spendelow JA (2004) Estimation of sex-specific survival from capture-recapture data when sex is not always known. Ecology 85:3192–3201CrossRefGoogle Scholar
  11. Pfister CA (1998) Patterns of variance in stage-structured populations: evolutionary predictions and ecological implications. Proc Natl Acad Sci USA 95:213–218PubMedCrossRefGoogle Scholar
  12. Pradel R (2005) Multievent: an extension of multistate capture-recapture models to uncertain states. Biometrics 61:442–447PubMedCrossRefGoogle Scholar
  13. Seamans ME, Gutiérrez RJ (2006) Spatial dispersion of spotted owl sites and the role of conspecific attraction on settlement patterns. Ethol Ecol Evol 18:99–111CrossRefGoogle Scholar
  14. Seamans ME, Gutiérrez RJ (2007) Sources of variability in spotted owl population growth rate: testing predictions using long-term mark-recapture data. Oecologia 152:57–70PubMedCrossRefGoogle Scholar
  15. Seamans ME, Gutiérrez RJ, May CA, Peery MZ (1999) Demography of two Mexican spotted owl populations. Conserv Biol 13:744–754CrossRefGoogle Scholar
  16. Weathers WW, Hodum PJ, Blakesley JA (2001) Thermal ecology and ecological energetics of California spotted owls. Condor 103:678–690CrossRefGoogle Scholar

Copyright information

© Dt. Ornithologen-Gesellschaft e.V. 2010

Authors and Affiliations

  • D. I. MacKenzie
    • 1
  • M. E. Seamans
    • 2
  • R. J. Gutiérrez
    • 3
  • J. D. Nichols
    • 4
  1. 1.Proteus Wildlife Research ConsultantsDunedinNew Zealand
  2. 2.Division of Migratory Bird ManagementUSFWSLaurelUSA
  3. 3.Department of Fisheries, Wildlife and Conservation BiologyUniversity of MinnesotaSt PaulUSA
  4. 4.Patuxent Wildlife Research CenterUSGSLaurelUSA

Personalised recommendations