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BB1 - Abundance and distribution of seals (M3)

FieldDescriptionValidated Entry
[Table title]Name of monitoring programmeAbundance and distribution of seals (M3)
[ProgrammeDescription]Description of the monitoring programme

Atlantic grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina) are both regularly found in OSPAR Regions I, II and III. As higher predators, seals can be used as an indicator to reflect the state of the marine ecosystem. Assessment of seal abundance and distribution aims to determine if populations of both species are in a healthy state, with no long-term decrease in population size, beyond natural variability. Historically, populations have declined due to anthropogenic influences. Seal abundance and distribution are influenced by many factors, such as disease, competition with other species, changes in the distribution and abundance of prey, disturbance and interactions with fisheries. Seals were hunted into the 20th century, and as a result have disappeared entirely in some areas, but are now protected in most areas of Europe. Future changes in distribution or declines in abundance may signal that populations are no longer in a healthy state. Further studies would then be needed to establish the cause of these changes and to determine whether management measures are required.

The monitoring required for seal indicator M3 is on the numbers and location of individuals on land at colonies or haulout sites throughout OSPAR regions I, II and III. Surveys are usually conducted from the air, but may also be conducted from land or by boat. In most areas, aerial surveyors take photographs of the haul-out sites and animals are later counted from the images. There are two periods during the year when most grey and harbour seal surveys take place: breeding (pupping) and moulting. Harbour seals give birth to pups in early summer and moult after breeding in late summer. Grey seals pup in the autumn or winter and moult in early spring. The frequency of surveys during these periods varies across OSPAR Contracting Parties due to differences in the total number of resident animals, funding, geography and historical development of the monitoring programmes. Repeated surveys of both grey and harbour seals throughout the year are not economically feasible and Contracting Parties use population censuses in one or perhaps two seasons of the year.

[OtherPoliciesConventions]Monitoring for other Union legislation or international agreements that contributes to the programme.OSP-CEMP
[Contracting Parties monitoring]

Which other countries are involved in practical implementation of this monitoring programme, and what is the degree of cooperation.

Agreed data collection methods

[Contracting Parties supplying data] DE, DK, FR, NL, NO, UK
[Contracting Parties with an "opt out"]  
[Temporal scope]Start (and end) date of the programme.1960 - 9999
[Spatial scope]Spatial coverage of the programme according to the jurisdictional zones of marine waters.Terrestrial part of MS
[Aggregation of Data]At which scale can the data from the sub-programme be aggregated for environmental assessments?Regions (II & III)
[MarineReportingUnit]Area(s) where the programme takes place.marineSubregion

[Monitoring Purpose]

Purpose of the programme aimed at collecting data and information.Environmental state and impacts
[MonitoringType]Type of monitoring (in-situ, remote sensing, etc.).In-situ sampling land/beach
In-situ sampling coastal
Remote flight imagery (orthoimages)
[Indicator Metric]Feature(s) monitored (ecosystem components, pressures, activities).MamSeals
[Elements]Element(s) monitored (e.g. species, habitats, contaminants).Halichoerus grypus
Phoca vitulina
[Element Monitored] Marine Mammals: Seals; Grey seal (Halichoerus grypus) and Harbour seal (Phoca vitulina)
[Parameter Measured]Parameter(s) monitored.ABU
[Monitoring Guidelines/Monitoring Method in place]Guidelines/protocols describing the method for monitoring.OTH
[MonitoringMethodOther]Guidelines/protocols describing the method for monitoring.National guidelines; each CP should have their own guidelines in place
[Quality Assurance Procedures in Place]In addition to a specified method, is there any additional Quality Assurance used?National standards; each CP should have their own QA process
[Quality Control]What type of Quality Control is used?Other QC; each CP should have their own QC process
[Data submission Frequency (and deadline)]Frequency of the monitoringOther (Seal phenology will vary from species to species and from one CP to another and in some cases within a Contracting Parties waters, so monitoring is at varied requencies)
[Applicable MSFD GES Criteria]Indicator(s) to which the programme contributes.D1C2
[Data Depository]Link to where monitoring data can be accessed (Art. 19(3) 
[Data Custodian] ICES
[Assessment Guidelines] CEMP Guideline: Common Indicator - Seal Abundance and Distribution (M3) (Agreement 2016-11)
[Assessment tools available]  
[Nature of data] Unprocessed
BB1 - Seal Abundance and Distribution