Interim report of the HELCOM CORESET project

11. Temporal considerations
Frequency: ideally as often as possible, but realistically perhaps every fi fth year
12. Current monitoring
Monitoring done in all the Contracting States. Measured parameters must be compared and the indicator
species agreed and included in the monitoring.
13. Proposed or perceived target setting approach with a short justifi cation.
The reference level for each seabird population should be set at a population size that is considered
desirable for each individual species within each geographical area. This should be set for each species
based on expert judgement of when population levels were subject to low impact by human activities.
In the OSPAR EcoQO the target level was set to the level of standard deviation from the reference level.
The lower target depended, however, partly on the species; species laying one egg were given stricter
target (being more sensitive) than species laying more eggs.
The proportion of species reaching their target is the “integrated indicator”. The target level could be
75% as in the OSPAR EcoQO.
Additional indicators for the breeding seabird populations
The abundance of breeding seabirds is a good indicator for following long-term changes, whereas it is not
feasible for detecting short-term changes. Short-term responses to environmental changes can be better
followed by reproductive parameters, such as breeding success or brood size. The OSPAR EcoQO (under
development) for the breeding success of the kittiwake is an example of such an indicator. It may be used
as an indicator for the abundance of sandeel that also serves as a major food source for many other bird,
fi sh and marine mammal species. Sandeel availability may be low because of natural reasons, or through
industrial fi shing that competes with seabirds. When the breeding success of kittiwake is low over a threeyear
period, this is likely to be triggered by low abundance of sandeel in coastal areas. The indicator thus
shows the status of sandeel and kittiwake populations and the need to reduce industrial fi shing.
In the Baltic Sea, the availability of data on brood size and breeding success needs to be clarifi ed.
The national monitoring programmes to monitor the breeding populations of sea birds can be also used to
develop a distribution indicator. The indicator would require sub-basin wise species selection and setting
of GES boundaries. In addition, it should be decided which density threshold is used to determine the
margin of distribution.
4.6. Proportion of seabirds being oiled
1. Working team
Sea birds
2. Name of candidate indicator
Proportion of seabirds being oiled
3. Unit of the candidate indicator
Number of oiled seabirds per species
4. Description of proposed indicator
Proportion of oiled seabirds found in the winter-time population counts are being used for the estimate
of this indicator.
In addition, proportion of oiled seabirds among those found dead or dying on beaches can be used as
an additional information.
5. Functional group or habitat type
Mainly offshore benthic feeders and offshore pelagic and surface feeding birds
6. Policy relevance
Descriptor 1
Descriptor 4
165