Grey literature
Forth and Tay Estuary winter seaduck surveys
Moray and Dornoch Firth seaduck surveys
Evans, R.J. 1992. Moray Firth Monitoring Winter 1991/92. RSPB report.
Evans, R.J. 1993. Moray Firth Monitoring Winter 1992/93. RSPB report.
Stenning, J. 1994. Moray Firth Monitoring Winter 1993/94. RSPB report.
Stenning, J. 1995. Moray Firth Monitoring Winter 1994/95. RSPB report.