Hellenic Ornithological Society, photo: I.Foufopoulos
Identification of Marine Important Bird Areas (Marine IBAs) - 1 of 2

A BirdLife International project onImportant Bird Areas (IBAs) that started in early 1980s’, has created an extensive network of IBAs, which consisting of more than 10.000 areas, primarily terrestrial, throughout the world. In Greece, HOS has identified 196 IBAs of which only a small percentage includes a marine component.

The need for identification of IBAs in the marine environment (marine IBAs) was obvious from the beginning, however the systematic surveys of the distribution and activities of birds at sea for the delineation of marine IBAs are being carried out only during the last decade. The main reason for this delays were lack of appropriate standardized methods of recording seabirds at sea, lack of technology for monitoring seabird movements as well as large costs of surveys at sea.

The need for the identification of marine IBAs was further increased towards the end of the 20th century seabirds when it became evident that seabirds are the most threatened group of birds, worldwide. In Europe this situation lead to an intensive development of new methods for the survey and monitoring of seabirds and increased funding opportunities for national marine IBA projects.

Marine IBA identification process in Greece started in 2007, with the project “Survey and Conservation of Seabirds in Greece”, funded by the A.G. Leventis Foundation and was further expanded with the present LIFE-Nature project in 2009.

One of the main objectives of the LIFE project is the identification of Marine IBAs for the Mediterranean Shag (Phalacrocorax aristotelis desmarestii) and the Audouin’s Gull (Larus audouinii), two priority species, listed in Annex I of the Birds Directive, that breed in significant numbers in Greece.

There are four types of marine IBAs:
1. Seaward extensions of the seabirds colonies in the existing terrestrial IBAs
2. Coastal and inshore marine areas hosting concentrations of seabirds
3. Pelagic areas hosting concentrations of seabirds
4. Migrations hotspots

For the purpose of marine IBA designation in Greece, systematic surveys are being carried out to collect data regarding the seabird distribution at sea and along the coast as well as the distribution of seabird colonies. The methods applied include census of seabird colonies on islands and islets, recording of seabirds at sea with research boats and ferry boats, telemetry using radio- and GPS tracking as well as bird ringing. These data are statistically analyzed in association with the oceanographic, fisheries and biological data to delineate marine IBAs.

The greatest achievement of the project “Survey and conservation of seabirds in Greece” was a pilot application and acquisition of experience in implementation of all methods required for designation of marine IBAs. Therefore the present LIFE project provided the opportunity to apply these methods to a full extent in 17 project SPA sites with special emphasis on the Mediterranean Shag and Audouin’s Gull. The actions related to marine IBA identification will continue until 2012 when a full inventory of marine IBAs in the project areas will be produced.

Following below are detailed descriptions of the project actions related to marine IBA designation

Seabird surveys

Recording seabirds at sea (ESAS)  

One of the main project actions related to the designation of marine IBAs is recording seabirds at sea with the method European Seabirds at Sea (ESAS). This method was first applied in the beginning of 1980s’ inNW Europe, and since 2007 it is also being applied in Greece.

The method is based on continuous recording of seabirds at sea along the ship route (line-transect), carried out from a ferry boat or a research boat travelling at a speed up to 20 knots.

The main goal of ESAS is to determine the distribution and activities of seabirds at sea.

The most common seabird species being recorded by ESAS in Greece, apart from the Mediterranean Shag and Audouin’s Gull are Cory’s Shearwater (Calonectris diomedea), Yelkouan Shearwater (Puffinus yelkouan), European Storm-petrel (Hydrobates pelagicus)  and Yellow-legged Gull (Larus michahellis). Apart from seabird presence, number of individuals and behaviour, ESAS also records other species of marine fauna (e.g. cetaceans, fish), human activities (e.g. fishing) and floating matter in order to explain why the seabirds use particular marine areas and to improve our understanding of their behavior and ecology.

The observation team usually consists of two experienced observers. While the first observer is observing seabirds at sea, the other is recording the data in specifically designed datasheets, one to bird records and one for the ship route.

The original ESAS datasheets were adapted to Greek conditions and the requirements of the project and translated in Greek.

A detailed description of the ESAS methodology is provided here

Within the present project ESAS surveys are being carried by MOm in the Northern Aegean Sea and by HOS in the rest of Greek marine areas.

From the beginning of the LIFE project in 2009 until autumn 2012, more than 260 survey trips of total distance more than 18.100km have been completed, covering all major regions of the Aegean and Ionian sea. During these trips in total more than 67.000 individuals of seabirds and other marine species have been recorded.

Volunteers play an important role in ESAS surveys. Training seminars for ESAS volunteers have been organized in 2009.

For further information regarding participation in volunteer ESAS surveys, please contact ESAS coordinator Jakob Fric.

It should be noted that the volunteer ESAS surveys are supported by MINOAN Lines, ANEK Lines, Blue Star Ferries και Superfast Ferries shipping companies that kindly provided  ferry boat tickets.

Coastal counts and coastal census

In parallel to the ESAS surveys, that take place primarily at open sea, coastal counts and coastal census record seabirds in coastal waters. These surveys are carried out on land and from a boat, respectively.

During coastal census, the observers record all the birds on the coast or coastal waters while the boat slowly follows the coastline. This method is a kind of line-transect method. The bird records are associated with census sectors in which the entire coastline of the survey areas has been divided. Similar methods has already been successfully applied in the first global census of the Eleonora’s Falcon (Falco eleonorae). The method is particularly suitable for recording seabird species that use coastal water for feeding and resting, which is the case of the Audouin’s Gull and the Mediterranean Shag. Until autumn 2012 coastal census surveys have covered more than 3000 km of coastline in the project sites.

Coastal counts on the other hand are carried out from selected observation points on the coast adjacent marine areas with concentrations of seabirds. This method is a kind of point-count methods. The observers with the use of a telescope and binoculars record the number and behavior of seabirds in order to determine the use of the marine areas by seabirds. Up till now 260 man-hour of coastal counts have been realized from selected locations on islands in the northern and central Aegean Sea and in the Northern Dodecanese.


Marine areas covered by seabird surveys (until autumn 2012)

Total number of recorded number of seabird individuals (until October 2010)


  Coastal census Coastal counts ESAS Total
Survey effort 2,972 km 12 sites/260h 18,192km 21,164 km
Larus audouinii 1,303 110 203 1,616
Phalacrocorax aristotelis 6,546 719 2,386 9,651
Calonectris diomedea 336 19,954 13,015 33,305
Puffinus yelkouan 183 71,004 19,953 90,140
Hydrobates pelagicus     17 17
Larus michahellis 32,533 1,236 29,126 62,895

* Caution! The above totals represent sums of all recorded individuals and do not correspond to seabird populations in project areas, because in several areas surveys were repeated in between 2009 and in 2012.

Distribution of recorded seabirds per species:

Mediterranean Shag:   Audouin’s Gull:   Cory’s Shearwater:
Yelkouan Shearwater:   Yellow-legged gull:    

Other species of seabirds and waterbirds recorded: Common sandpiper(Actitis hypoleucos), Common Kingfisher (Alcedo atthis), Mallard (Anas platyrhynchos), Garganey (Anas querquedula), Great Egret (Casmerodius albus), Grey Heron (Adrea cinerea), Πορφυροτσικνιάς (Ardea purpurea), Squacco Heron (Ardeola ralloides), Purple Heron(Charadrius dubius), Whiskered Tern (Chlidonias hybrida), Black Tern (Chlidonias niger), Little Egret (Egretta garzetta), Black-throated Diver (Gavia arctica), Red-throated Diver (Gavia stellata), Slender-billed Gull (Larus genei), Mediterranean Gull (Larus melanocephalus), Little Gull (Larus minutus), Black-headed Gull (Larus ridibundus), Cormorant (Phalacrocorax carbo), Great Crested Grege (Podiceps cristatus Little Tern (Sterna albifrons), Bridled Tern (Sterna anaethetus), Caspian Tern (Sterna caspia), Common Tern (Sterna hirundo), Arctic Skua (Stercorarius parasiticus) and Sandwich Tern (Sterna sandvicensis)

Οther marine species recorded:

Monk Seal (Monachus monachus), Common Dolphin (Delphinus delphis), Risso’s Dolphin (Grampus griseus), Ocean Sunfish (Mola mola), Sperm Whale (Physeter macrocephalus), Striped Dolphin (Stenella coeruleoalba), Bottlenose Dolphin (Tursiops truncatus), Swordfish (Xiphias gladius), Cuvier's Beaked Whale (Ziphius cavirostris) and Loggerhead Sea Turtle (Caretta caretta).


- ESAS datasheets( route datasheetrecords datasheet,  or both for EXCEL)

- ESAS guidelines (pdf


Telemetry has become of the main methods for the study of bird ecology in their natural environment and complementary to bird ringing tries to answer a basic question: What birds do beyond the visual field of view of an observer?

For this purpose and particularly during recent year, several types of telemetry methods have been developed and improved. These methods usually belong to one of three main categories: radiotracking, tracking using satellite systems like GPS or Argos, recording various environmental variables using dataloggers. Each of these methods has its advantages and is suitable answer particular scientific questions. Radiotracking is the most common technique because it is cheap and allows tracking of large number of individuals. However it requires great efforts and it has limited range. On the other hand, satellite telemetry systems have a remarkable spatial accuracy and range but their price is equivalently high. And above all the main limiting factor is the weight of tracking devices which birds carry but should not obstruct them. Therefore the selection of the most suitable method is always a quest for the best compromise between capabilities and restrictions of each method.

In the framework of the LIFE project telemetry is being used for the study of daily and seasonal movements of selected individuals of Audouin’s Gull and Mediterranean Shag in order to determine the most important foraging and resting marine areas and migratory corridors used by bird breeding in the project areas. For this purpose 3 types of telemetry methods are being used:

1. Radiotracking

Selected individuals of target species are equipped with light-weight radio transmitters, which are then tracked with mobile antennas. The location of each individual with the tag is determined by triangulation.

2. GPS dataloggers

Dataloggers with a build-in GPS receiver are mounted on birds to record their positions with great spatial and temporal accuracy.

3. Geolocators

Geolocators are dataloggers which record the intensity of sunlight. The location of the birds is determined from the time of sunrise and sunset as well as the duration of the day.

Apart from using above telemetry methods for monitoring bird movements and behavior at sea, bird movements and migration are being surveyed by bird ringing. A set of one metal and one plastic ring is mounted on juvenile and adults Mediterranean Shags and Audouin’s Gulls to allow for their future recovery and recognition.


Up until summer 2012, 32 Audouin’s Gulls from N. Aegean Sea and N. Dodecanese have been equipped radiotransmitters, GPS dataloggers and geolocators and 32 Shags from the N. Aegean Sea with radiotransmitters.


  Map of recovered ringed Audouin;s Gulls in the Mediterranean region


continue here for second part of marine IBA identification

Θαλασσοκόρακας & Αιγαιόγλαρος

take part in the Greek seabird population census

 Identify six seabirds at a glance!

Dark coloured, long necked and short tail

Mediterranean Shag: rounded crown, steep forehead, slender bill, thin straight neck.

Dark coloured, long wings, just above the water

Cory’s Shearwater: brown above, white below, long glides.
Mediterranean Shearwater: dark above, light below, quick wingbeats. Usually in flocks.

White coloured gull, with long wings 

Yellow-legged Gull: light-coloured bill, eyes and legs. Dark grey mantle with white edge, and black wing tips, with large white spots. Yellow bill. Most common gull.
Audouin’s Gull: dark-coloured bill, eye and legs. Light grey mantle without obvious white edge and black wing tips, with small white spots. Red bill. Typically observed close to islands and small islets.

Tiny, black, just above the water

Storm-petrel: very small, white rump like a swallow. Very rare

LIFE Natura 2000

LIFE07 NAT/GR/000285
Concrete conservation actions for the Mediterranean Shag and Audouin's Gull in Greece, including the inventory of relevant marine IBAs

The project is implemented by the Hellenic Ornithological Society, in collaboration with the Hellenic Society for the Study and Protection of the Monk Seal (ΜΟm), the Hellenic Centre for Marine Research (HCMR), the Technological Institution (TEI) of Ionian Islands and the Portuguese Society for the Study of Birds (SPEA), with the financial support of the European Commission and the co-financing of the A.G. Leventis Foundation.
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Last update: October 5, 2012

Coordinating beneficiary

Associated beneficiaries



Hellenic Ornithological Society Hellenic Society for the Study and Protection of the Monk Seal (ΜΟm) Hellenic Centre for Marine Research (HCMR) Technological Institution (TEI) of Ionian Islands Portuguese Society for the Study of Birds (SPEA) A.G. Leventis Foundation
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