Observer error in sampling a rare plant population

References

• Al-Shehbaz IA. 2010. Brassicaceae. In: Editorial Committee, editors. Flora of North America. New York (NY): Oxford University Press. p. 224–746.
   Google Scholar
• Archaux F. 2009. Could we obtain better estimates of plot species richness from multiple-observer plant censuses? Journal of Vegetation Science 20:603–611.
   Web of Science ®Google Scholar
• Archaux F, Bergès L, Chevalier R. 2007. Are plant censuses carried out on small quadrats more reliable than on larger ones? Plant Ecology 188:179–190.
   Web of Science ®Google Scholar
• Archaux F, Camaret S, Dupouey J-L, Ulrich E, Corcket E, Bourjot L, Brêthes A, Chevalier R, Dobremez J-F, Dumas Y, et al. 2009. Can we reliably estimate species richness with large plots? An assessment through calibration training. Plant Ecology 203:303–315.
   Web of Science ®Google Scholar
• Bergstedt J, Westerberg L, Milberg P. 2009. In the eye of the beholder: bias and stochastic variation in cover estimates. Plant Ecology 204:271–283.
   Web of Science ®Google Scholar
• Bråkenhielm S, Qinghong L. 1995. Comparison of field methods in vegetation monitoring. Water, Air, & Soil Pollution 79:75–87.
   Web of Science ®Google Scholar
• Burg S, Rixen C, Stöckli V, Wipf S. 2015. Observation bias and its causes in botanical surveys on high-alpine summits. Journal of Vegetation Science 26:191–200.
   Web of Science ®Google Scholar
• Campbell NA, Arnold GW. 1973. The visual assessment of pasture yield. Australian Journal of Experimental Agriculture and Animal Husbandry 13:263–267.
   Google Scholar
• Carlsson ALM, Bergfur J, Milberg P. 2005. Comparison of data from two vegetation monitoring methods in semi-natural grasslands. Environmental Monitoring and Assessment 100:235–248.
   PubMed Web of Science ®Google Scholar
• Cheal D. 2008. Repeatability of cover estimates? Ecological Management & Restoration 9:67–68.
   Google Scholar
• Chen G, Kéry M, Zhang J, Ma K. 2009. Factors affecting detection probability in plant distribution studies. Journal of Ecology 97:1383–1389.
   Web of Science ®Google Scholar
• Elzinga CL, Salazar DW, Willoughby JW, Gibbs JP. 2001. Monitoring plant and animal populations. Oxford (UK): Blackwell Science.
   Google Scholar
• Goodall DW. 1952. Some considerations in the use of point quadrats for the analysis of vegetation. Australian Journal of Biological Science 5:1–41.
   Google Scholar
• Gorrod EJ, Keith DA. 2009. Observer variation in field assessments of vegetation condition: implications for biodiversity conservation. Ecological Management & Restoration 10:31–40.
   Google Scholar
• Gray AN, Azuma DL. 2005. Repeatability and implementation of a forest vegetation indicator. Ecological Indicators 5:57–71.
   Web of Science ®Google Scholar
• Hahn I, Scheuring I. 2003. The effect of measurement scales on estimating vegetation cover: a computer-assisted experiment. Community Ecology 4:29–33.
   Google Scholar
• Hall JB, Okali DUU. 1978. Observer bias in a floristic survey of complex tropical vegetation. The Journal of Ecology 66:241–250.
   Web of Science ®Google Scholar
• Hope-Simpson JF. 1940. On the errors in the ordinary use of subjective frequency estimations in grassland. The Journal of Ecology 28:193–209.
   Google Scholar
• IBM Corp. 2011. IBM SPSS statistics, version 20.0. Armonk (NY): IBM Corp.
   Google Scholar
• Kennedy KA, Addison PA. 1987. Some considerations for the use of visual estimates of plant cover in biomonitoring. The Journal of Ecology 75:151–158.
   Web of Science ®Google Scholar
• Kercher SM, Frieswyk CB, Zedler JB. 2003. Effects of sampling teams and estimation methods on the assessment of plant cover. Journal of Vegetation Science 14:899–906.
   Web of Science ®Google Scholar
• Kéry M, Gregg KB. 2003. Effects of life-state on detectability in a demographic study of the terrestrial orchid Cleistes bifaria. Journal of Ecology 91:265–273.
   Web of Science ®Google Scholar
• Klimeš L. 2003. Scale-dependent variation in visual estimates of grassland plant cover. Journal of Vegetation Science 14:815–821.
   Web of Science ®Google Scholar
• Klimeš L, Dančak M, Hájek M, Jongepierová I, Kučera T. 2001. Scale-dependent biases in species counts in a grassland. Journal of Vegetation Science 12:699–704.
   Web of Science ®Google Scholar
• Legg CJ, Nagy L. 2006. Why most conservation monitoring is, but need not be, a waste of time. Journal of Environmental Management 78:194–199.
   PubMed Web of Science ®Google Scholar
• Lepš J, Hadincová V. 1992. How reliable are our vegetation analyses? Journal of Vegetation Science 3:119–124.
   Web of Science ®Google Scholar
• McCune B, Dey JP, Peck JE, Cassell D, Heiman K, Will-Wolf S, Neitlich PN. 1997. Repeatability of community data: species richness versus gradient scores in large-scale lichen studies. The Bryologist 100:40–46.
   Web of Science ®Google Scholar
• Moore JL, Hauser CE, Bear JL, Williams NSG, McCarthy MA. 2011. Estimating detection-effort curves for plants using search experiments. Ecological Applications 21:601–607.
   PubMed Web of Science ®Google Scholar
• Morrison LW. 2016. Observer error in vegetation surveys: a review. Journal of Plant Ecology 9:367–379.
   Web of Science ®Google Scholar
• Morrison LW, Smith DR, Young CC, Nichols DW. 2008. Evaluating sampling designs by computer simulation: a case study with the Missouri bladderpod. Population Ecology 50:417–425.
   Web of Science ®Google Scholar
• Murphy SR, Lodge GM. 2002. Ground cover in temperate native perennial grass pastures. I. A comparison of four estimation methods. The Rangeland Journal 24:288–300.
   Web of Science ®Google Scholar
• Oredsson A. 2000. Choice of surveyor is vital to the reliability of floristic change studies. Watsonia 23:287–291.
   Google Scholar
• Ringvall A, Petersson H, Ståhl G, Lämås T. 2005. Surveyor consistency in presence/absence sampling for monitoring vegetation in a boreal forest. Forest Ecology and Management 212:109–117.
   Web of Science ®Google Scholar
• Scott WA, Hallam CJ. 2002. Assessing species misidentification rates through quality assurance of vegetation monitoring. Plant Ecology 165:101–115.
   Web of Science ®Google Scholar
• Smith AD. 1944. A study of the reliability of range vegetation estimates. Ecology 25:441–448.
   Google Scholar
• Stapanian MA, Cline SP, Cassell DL. 1997. Evaluation of a measurement method for forest vegetation in a large-scale ecological survey. Environmental Monitoring and Assessment 45:237–257.
   Web of Science ®Google Scholar
• Sykes JM, Horrill AD, Mountford MD. 1983. Use of visual cover assessments as quantitative estimators of some British woodland taxa. The Journal of Ecology 71:437–450.
   Web of Science ®Google Scholar
• Symstad AJ, Wienk CL, Thorstenson AD. 2008. Precision, repeatability, and efficiency of two canopy-cover estimate methods in northern Great Plains vegetation. Rangeland Ecology & Management 61:419–429.
   Web of Science ®Google Scholar
• Thomas LP, Willson GD. 1992. Effects of experimental trampling on the federally endangered species, Lesquerella filiformis Rollins, at Wilson’s Creek National Battlefield, Missouri. Natural Areas Journal 12:101–105.
   Google Scholar
• Tonteri T. 1990. Inter-observer variation in forest vegetation cover assessments. Silva Fennica 24:189–196.
   Google Scholar
• Vittoz P, Bayfield N, Brooker R, Elston DA, Duff EI, Theurillat J-P, Guisan A. 2010. Reproducibility of species lists, visual cover estimates and frequency methods for recording high-mountain vegetation. Journal of Vegetation Science 21:1035–1047.
   Web of Science ®Google Scholar
• Vittoz P, Guisan A. 2007. How reliable is the monitoring of permanent vegetation plots? A test with multiple observers. Journal of Vegetation Science 18:413–422.
   Web of Science ®Google Scholar
• Wintle BC, Fidler F, Vesk PA, Moore JL. 2013. Improving visual estimation through active feedback. Methods in Ecology and Evolution 4:53–62.
   Web of Science ®Google Scholar
• Young CC, Kelrick MI, Morrison LW, DeBacker MD, Haack JL, Rowell GA 2008a. Missouri bladderpod monitoring protocol for Wilson’s creek national battlefield. Natural Resource Report NPS/MWR/HTLN/NRR—2008/043. Fort Collins (CO): National Park Service.
   Google Scholar
• Young CC, Morrison LW, Haack JL. 2009. Habitat relationships and management implications for Lesquerella filiformis Rollins (Missouri bladderpod) on a xeric limestone prairie. The Journal of the Torrey Botanical Society 136:233–241.
   Google Scholar
• Young CC, Morrison LW, Kelrick MI, DeBacker MD. 2008b. Monitoring Lesquerella filiformis Rollins (Missouri bladderpod): application and evaluation of a grid-based survey approach. Natural Areas Journal 28:370–378.
   Web of Science ®Google Scholar