The data and resulting data products (tables, figures and maps) available on the indicator web page can be used freely given that the source is cited. The indicator should be cited as following:
HELCOM (2018) Abundance of waterbirds in the breeding season. HELCOM core indicator report. Online. [Date Viewed], [Web link].
ISSN 2343-2543
Result: Abundance of waterbirds in the breeding season
Data: Abundance of waterbirds in the breeding season
Result: Abundance of waterbirds in the breeding season - surface
Result: Abundance of waterbirds in the breeding season - pelagic
Result: Abundance of waterbirds in the breeding season - benthic
Result: Abundance of waterbirds in the breeding season – grazing
Result: Abundance of waterbirds in the breeding season - wading
Following a data call in May 2017, breeding bird data of 30 species for the years 1991-2016 were supplied by authorities from Contracting Parties of HELCOM, except Russia and Lithuania. Breeding bird abundance was reported in numbers of breeding pairs, but Swedish data referred to numbers of males and individuals. The use of different units did not cause problems, because calculations are done on the basis of population indices rather than on population sizes. Data sets consisted of site code, year, species and abundance. Data were supplied for a total of 11164 sites, but each species had different numbers of sites used in the analysis.
