Data for 'Immigration counter-acts local micro-evolution of a major fitness component: migration-selection balance in free-living song sparrows' Reid et al., Evolution Letters, 2021 This file contains summary data for the number of immigrants and all adults alive in each year. These data come from the long-term song sparrow field study on Mandarte Island, BC, Canada. The data provided here are sufficient to replicate the analyses presented in the above paper, and are therefore a restricted subset of the full Mandarte dataset. If you are interested in running further analyses that require further data then please get in touch with Prof Peter Arcese (University of British Columbia), Prof Lukas Keller (University of Zurich) or Prof Jane Reid (University of Aberdeen / NTNU). We are always happy to develop collaborations with researchers who have good ideas for new analyses. We'd also appreciate it if you could let us know if you are intending to make use of the dataset below in order to facilitate coordination of different ongoing research efforts and allow us to keep track of all outputs from the long-term field study. "year" is the year "no.imms" is the total number of immigrants present in each year "no.imms" is the total number of adults present in each year "prop.imms" is the proportion of adults present in each year that were immigrants "year" "no.imms" "tot.ads" "prop.imms" 1981 2 47 0.04 1982 1 71 0.01 1983 1 120 0.01 1984 2 141 0.01 1985 3 159 0.02 1986 3 130 0.02 1987 3 126 0.02 1988 6 105 0.06 1989 1 12 0.08 1990 4 24 0.17 1991 5 55 0.09 1992 5 87 0.06 1993 3 113 0.03 1994 1 127 0.01 1995 2 112 0.02 1996 2 128 0.02 1997 2 114 0.02 1998 4 92 0.04 1999 2 57 0.04 2000 2 55 0.04 2001 2 43 0.05 2002 2 62 0.03 2003 2 59 0.03 2004 1 48 0.02 2005 3 72 0.04 2006 1 62 0.02 2007 0 33 0 2008 3 65 0.05 2009 3 51 0.06 2010 4 68 0.06 2011 3 51 0.06 2012 4 94 0.04 2013 3 75 0.04 2014 2 59 0.03 2015 3 33 0.09 2016 1 21 0.05 2017 3 44 0.07 2018 1 45 0.02 2019 1 33 0.03