Tuule, E.; Tuule, A.; Lõhmus, A. 2011. Fifty-year dynamics in a temperate raptor assemblage. Estonian Journal of Ecology, 60(2), 132 - 142.
Elts, J., Kuresoo, A., Leibak, E., Leito, A., Leivits, A., Lilleleht, V., Luigujõe, L., Mägi, E. et al. 2009. Status and numbers of Estonian birds, 2003–2008. Hirundo 22, 3–32.
Lõhmus, A. 1999. Monitoring raptors and owls, 1994-1998. Hirundo 12, 19-35.
Lõhmus, A. 2004. Monitoring raptors and owls in Estonia, 1999-2003: decline of the Goshawk and the Clockwork of vole-cycles. Hirundo 17, 3–18.
Tuule, E., Tuule, A. & Lõhmus, A. 2007. Nesting ecology of birds of prey and owls near Saue, 1959-2006. Hirundo 20, 14–6.
All raptor species are monitored annually on permanent study plots (the minimum size of a plot is 50 km2), which are located in different counties all over the country. There were 13 such plots in 2011, with a total area of 1345 km2. The number of species, the number of occupied territories and information about productivity are gathered from these plots.