Monitoring of breeding waterbirds in the Contracting Parties of HELCOM is described on a general level in the HELCOM Monitoring Manual in the sub-programme: Marine breeding birds abundance and distribution.
Specific monitoring guidelines for breeding waterbirds are planned to be included into the Monitoring Manual.
The indicator on breeding waterbirds is primarily based on counts of breeding pairs or nests along the shorelines of the Baltic Sea, i.e. is restricted to coastal landscape (including islands). Many species only breed in nature reserves or other protected sites, which have been monitored using constant methods for decades. In many sites, breeding birds are counted annually, and gaps can be filled by a TRIM analysis.
Breeding success is usually measured as the number of fledged chicks per breeding pair. Methods to observe the reproductive output differ between species. For instance, in Great Cormorants it is possible to count the nearly-fledged juveniles in the nests, whereas in gulls and terns reliable data are available only when movements of the non-fledged offspring are restricted by fencing or when mark-recapture methods are applied.
The monitoring activities relevant to the indicator that are currently carried out by HELCOM Contracting Parties are described in the HELCOM Monitoring Manual in the monitoring concepts table.
Sub-programme: Marine breeding birds abundance and distribution
Monitoring Concepts table
There are some differing characteristics in the countries' monitoring programmes, e.g. the species covered and the temporal scaling. Surveys are in most cases conducted annually, but every three or six years (as an adaptation to Natura 2000 reporting cycles, see European Commission 1992, 2010) or even every ten years (e.g. common eider in Denmark) in some cases. Some new monitoring schemes, such as the 2015 spring monitoring scheme in Sweden, will be implemented in the near future, however recent overviews of monitoring of breeding waterbirds are still valid, e.g. the BALSAM metadatabase or the project's interim report (HELCOM 2014).
For abundance of breeding birds, the currently operational national monitoring schemes are only partly sufficient to supply the necessary data for the indicator. There are still gaps regarding spatial coverage (lack of monitoring schemes in Russia and Latvia) and coverage of species (not all monitoring schemes include all the species dealt with in the indicator), and an optimal monitoring would have to close these gaps. The monitoring methods applied could benefit from international standardization, however, need to take into consideration the varying environmental conditions and species composition of the different regions of the Baltic Sea. As not all species can be monitored in every country, depending on the assessment unit level chosen, it would be wise to coordinate national monitoring schemes in a way that allows for coverage of as many species as possible. For rare species, and those showing higher degrees of inter-annual relocation, coordinated Baltic-wide surveys should be aspired for in order to minimize the effects of data gaps and low site fidelity.
Breeding success is currently not monitored sufficiently to allow for any status evaluation. In order to improve the confidence of the indicator evaluation, breeding success should be included in monitoring activities at least for the key species in the main breeding colonies throughout the Baltic Sea region.