Annual index results for British Columbia

Annual index graph for: Bobolink

Note: the range of the vertical axis has been scaled to highlight pattern in the annual indices. If estimates are imprecise, the graph may not include the upper credible limits.

View definitions of the annual index table columns.

Annual indices for Bobolink in British Columbia
Year Annual index Lower limit Upper limit
1970 0.134 0.0504 0.383
1971 0.143 0.0629 0.391
1972 0.141 0.0662 0.322
1973 0.145 0.0751 0.293
1974 0.162 0.0955 0.32
1975 0.157 0.0962 0.277
1976 0.146 0.0868 0.238
1977 0.158 0.0973 0.26
1978 0.167 0.109 0.26
1979 0.184 0.122 0.286
1980 0.203 0.14 0.31
1981 0.221 0.151 0.347
1982 0.224 0.154 0.342
1983 0.224 0.154 0.343
1984 0.234 0.161 0.367
1985 0.221 0.151 0.344
1986 0.219 0.15 0.342
1987 0.203 0.136 0.334
1988 0.199 0.135 0.323
1989 0.183 0.123 0.288
1990 0.184 0.123 0.29
1991 0.173 0.113 0.274
1992 0.172 0.111 0.274
1993 0.179 0.119 0.283
1994 0.184 0.125 0.294
1995 0.185 0.126 0.298
1996 0.188 0.127 0.302
1997 0.186 0.128 0.295
1998 0.182 0.125 0.287
1999 0.174 0.12 0.28
2000 0.168 0.111 0.272
2001 0.16 0.105 0.252
2002 0.163 0.11 0.27
2003 0.155 0.103 0.252
2004 0.146 0.0945 0.23
2005 0.142 0.0948 0.242
2006 0.127 0.0827 0.207
2007 0.113 0.071 0.183
2008 0.0991 0.0614 0.164
2009 0.0918 0.0568 0.159
2010 0.0815 0.0498 0.142
2011 0.0678 0.0391 0.119
2012 0.0608 0.0339 0.109
2013 0.0501 0.0262 0.0928
2014 0.0419 0.0207 0.0821
2015 0.0343 0.0159 0.0706
2016 0.0283 0.0116 0.0646
2017 0.0222 0.0082 0.056
2018 0.0173 0.0056 0.0501
2019 0.0134 0.00382 0.0443

Geographic area included in the Long-term trend for the Bobolink

Map displaying regions covered by analysis of species: Bobolink
      Coloured = Regions (analytical strata) included in trend estimate. The colour of the region reflects the approximate population trend in the region. The categories of trends based on the %/year values are indicated in the legend on the right, and the specific values can be found by searching on the analytical stratum trends for the same time-period and species.
      White = Regions not included in trend estimate

Bird Conservation Regions (BCR) with data included in Long-term trend estimates for British Columbia

Bird Conservation Regions (BCR) with data excluded from long-term trend estimates for British Columbia, but included in short-term estimates

This web site may be cited as: Smith, A.C., Hudson, M-A.R. Aponte, V.I., and Francis, C.M. 2020. North American Breeding Bird Survey - Canadian Trends Website, Data-version 2019. Environment and Climate Change Canada, Gatineau, Quebec, K1A 0H3

Any use of these BBS results for Canada should acknowledge the hundreds of skilled volunteers in Canada who have participated in the BBS over the years and those who have served as provincial or territorial coordinators for the BBS.

  1. Smith, A. C., & Edwards, B. P. M. (2020). North American Breeding Bird Survey status and trend estimates to inform a wide range of conservation needs, using a flexible Bayesian hierarchical generalized additive model. The Condor, duaa065. https://doi.org/10.1093/ornithapp/duaa065
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