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Marine IBA types
The Marine Important Bird Areas, or marine IBAs, are those IBAs that can be regarded as being marine in nature because of the seabird populations they contain and as such they are not fundamentally distinct from other IBAs that have been identified in terrestrial or freshwater environments (BirdLife International 2010b). All IBAs, including marine IBAs, are selected according to the same IBA criteria and follow the same site-based approach, where specific
actions are likely to achieve greatest conservation benefits (Appendix 10.1). Marine IBAs however are distinct from other IBAs with respect to the habitats present, the types of data used to describe sites and the methods for defining their boundaries (see Chapter 6). Based on different seabird distribution patterns identified up to date, the following four types of marine IBAs can be distinguished (adopted from BirdLife International 2010b):
Seaward extensions to breeding colonies While many seabird breeding colonies have already been identified as IBAs, their boundaries have been, in almost all cases, confined to the land on which the colonies are located. The boundaries of these sites can, in many cases, be extended to include those parts of the marine environment which are used by the colony for feeding, maintenance behaviours and
social interactions. Such extensions are limited by the foraging range, depth and/or habitat preferences of the species concerned. The seaward boundary is, as far as possible, colony and/or species-specific, based on known or estimated foraging and maintenance behaviour.
Mediterranean Shag (Phalacrocorax aristotelis)
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