Marine Mammals
& Sea Turtles


The eastern Mediterranean Sea supports some of the most important remaining marine mammal and sea turtle populations in the Mediterranean. These populations include one species of baleen whales (fin whales), ten species of toothed whales (bottlenose dolphins, common dolphins, striped dolphins, Risso's dolphin, Cuvier's beaked whales, Mesoplodon sp., false killer whale, sperm whale, long-finned pilot whale, harbor porpoises).

This part of the Aegean also supports the most important remaining populations of the Mediterranean monk seal, one of the most critically endangered marine mammals in the world, and three species of sea turtles (loggerhead turtle, green turtle, leatherback turtle). While some of the species are defined as regular, as in bottlenose dolphins and common dolphins, some are classified as rare species such as false killer whale, long-finned pilot whale and beaked whales. Harbor porpoise presence was only recorded in the north of the Aegean Sea.

Cetaceans, pinnipeds and sea turtles are face with various threats in the Mediterranean Sea, all related to human activities. The most serious threats on the cetacean populations in the Eastern Mediterranean Sea were identified as deliberate hunting, pollution, overfishing, by-catch, habitat destruction and noise.

Even though there are various national and international commissions and agreements to prevent the negative anthropogenic impacts on these species, there are no effective and sustainable conservation measures on cetaceans in the Aegean Sea. As a result, several of these species are considered at risk with a lack of effective conservation actions.

In Greece, with over 18,000 km of coastline and the sea surface area of approximately 220,000 km2, the collection of data regarding the populations and strandings of marine mammals and turtles is extremely difficult. The research carried out on these species is limited, and unfortunately strandings are rarely reported.

Since the beginning of its operation, Archipelagos’ research has focused on the assessment of marine mammal populations. This research involved working towards determining species populations, major threats and mitigation measures against population declines in various regions of the Greek seas. Currently taking place in the Aegean region, the Archipelagos’ research and conservation work aims to fill the basic knowledge gaps on marine mammals and to broaden the knowledge on the least studied populations of rare and endangered species.


Archipelagos works in line with many international agreements on the protection of flagship marine mammal species.


The Aegean Sea supports some of the most important remaining marine mammal and sea turtle populations of the Mediterranean, including bottlenose dolphins, common dolphins and sperm whales. Highly endangered Mediterranean monk seals are also present in the same area. Other rare species, such as harbor porpoises, have recently been sighted in the northern part of the Aegean. The whole region supports exceptional biodiversity, hosting top predators of the food chain which are all classified as at risk by the IUCN.


Marine mammal research aims to:

We are implementing projects that are not only going to favor the top predators of the food chain, but also species living under their umbrella. As marine mammals are the flagship species, any conservation measure focuses on these species, then escalated to the habitat scale. Even though continuous cetacean monitoring is vital to insure the compilation of accurate baseline data and the successful implementation of conservation actions, dedicated surveys are long missing in the Eastern Mediterranean Basin. We, as Archipelagos with a range of experts on the board, are launching our long-term dedicated marine mammal surveys in the Eastern Aegean Sea with a possible extension in coming years. Any conservation measures will be wrongly placed without the systematic surveys that are carried out throughout the year. Therefore, our ultimate goal is to update the regional statues of marine mammal populations, draw the zones for critical habitats to limit the impacts of major threats and finally to propose effective and sustainable conservation measures by combining research with public awareness campaigns.


Marine mammal research focuses on:

Marine mammal research is focused not only on collecting baseline data through visual and acoustic surveys, but also exploring their behavior to understand the habitat use and to investigate the impact of anthropogenic activities. Archipelagos brings together science and stakeholder experiences in the field for its guiding light. During the surveys two different platforms are used to collect data; land surveys and boat surveys. Additionally, we invite fishermen and tour boat crews to our surveys to support the active involvement of stakeholders to increase the sustainability of our projects.

We collect data on:

  • Cetacean abundance
  • Cetacean distribution
  • Cetacean behavior and behavior changes under the anthropogenic activities
  • Movement pattern, residency pattern and social structure through photo-identification
  • Archipelagos Stranding Response Network
  • Behavior of habituated Mediterranean Monk Seals
  • Toxicological and other laboratory analyses
  • Environmental education and raising awareness


  1. Marine mammal abundance

We use pre-determined transect lines during our boat surveys to increase our accuracy on estimating the abundance rate of cetaceans. Two different types of boat surveys are carried out. The first surveys are focused on the surrounding waters of Samos Island and the second survey covers a large area, including the whole Ikaria Sea. While the first survey is conducted once a week, mainly to collect data on behavior and to photograph the individuals, the second survey is carried out seasonally to focus on the cetacean abundance. Through estimating the abundance, we can provide information to update the species regional statues and learn the seasonal pattern of species area usage.

  1. Cetacean distribution

Combining the data collected in both of the boat surveys and land surveys, we map the distribution of each species. The distribution maps are created in monthly, seasonally and yearly bases. Through those maps, we can investigate if there is any overlap on area usage of not only different species but also we can explore the effect of fishing practices and marine traffic on cetacean habitats.

  1. Cetacean behavior and behavior changes under the anthropogenic activities

Even though animal behavior is, in comparison, a poorly investigated topic in the animal kingdom, behavior is the first cue to scientists about the health of the target population. Therefore, we use behavior as a guide not only to find the critical habitats, as in feeding and resting, but to investigate the effect of marine traffic and fishing practices. It is known that animals first show some type of behavioral changes when faced with undesirable conditions. However, if we miss those cues, the short term behavior transforms to area avoidance and eventually population decline. Thus, we collect behavioral data, during our land and boat surveys, to map important habitats and to analyze the behavioral changes under the anthropogenic pressure. Altogether, these data will help us implement effective conservation measure and management strategies.

  1. Movement pattern, residency pattern and social structure through photo-identification:

Photo-identification is an important tool to investigate the movement patterns, residency patterns and social structure of the individuals. Movement patterns can show us the area range that the species can be found which will eventually help us implement the protected area. While residency patterns point out the importance of habitat in the yearly and/or seasonal level, social structure gives us details on the strength of the individual bonds. This will not only help us understand the flow of knowledge in the group, but also shows their resiliency to anthropogenic impacts.

We collect photo-ID data during our boat surveys and analyze the nicks and scars, mainly on the dorsal fin. After cataloguing each individual according to those features, we carry on matching manually via specialized software.

  1. Archipelagos Stranding Response Network

Over the last decade, the Archipelagos Stranding Response Network has been developed with the cooperation of Archipelagos’ researchers and volunteers as well as local communities of the Aegean islands.

This network is dedicated to providing first aid and rescue in incidents of live strandings, entanglements and entrapments. When a protected species is found dead, the Archipelagos’ team performs a necropsy and collects samples for further toxicological and pathological analysis.

  1. Behavior of habituated Mediterranean monk seals

Since the spring of 2014, Archipelagos has been involved in daily monitoring and conservation of a young monk seal which displays a highly unusual behavior, approaching inhabited coastal areas and touristic beaches. Archipelagos’ team works closely with the local community in a unique conservation effort to ensure the wellbeing of this special seal pup and facilitate her reintroduction to the natural environment.

  1. Toxicological and other laboratory analyses

The extent of bioaccumulation of chemical contaminants is assessed in cooperation with specialized laboratories of several European universities, which conduct toxicological, pathological and genetic analyses on samples from the Archipelagos’ marine mammal tissue bank.

  1. Environmental education and awareness raising

The Archipelagos’ team is active in various parts of the Aegean, involving and engaging the island communities in its research and conservation efforts.  A wide variety of awareness raising material is produced, including leaflets, posters, booklets, children’s fairy tales, educational games and DVDs, while various awareness raising events, games and presentations, take place in island schools and communities throughout the year. For Archipelagos, this important investment is the key to a long-term protection of the Greek seas and the entire eastern Mediterranean.


surveys (1)Exploitation:

Many marine animals are hunted for commercial use, despite the fact that killing them is illegal in most countries nowadays.


Fisheries cause high mortality rate among marine animals when they get by-caught accidentally. Animals can get entangled in nets and drown. Lost and drifting nets can also be ingested. Ships cause death by direct strikes, especially among whales.

Conflict with fisheries:

Large fisheries have depleted fish stocks in many places, leading to the lack of prey for marine animals.

Habitat loss:

Habitat degradation endangers valuable environments needed for feeding and breeding.


Pollution in the form of noise and chemical contamination present in marine environments accumulates in bodies of marine mammals. Noise pollution caused by human activities is also a big concern as it disrupts echolocation.

Global climate change:

Global warming raises sea levels and changes water temperature as well as the directions of currents. This affects marine animals by altering prey distribution and changing the suitability of breeding sites.

Basic First Aid

strandedturtle-samos-Dec12-webUpon discovering a stranded, sick or injured animal alive, it is important to administer basic first aid whenever possible. Properly administered first aid can make the difference between life and death. In any case, the main priority is to avoid causing more stress to the animal, as this is a common cause of death. Avoid sudden and unnecessary movements, loud noises, close examinations and large crowds of people surrounding the animal.

Moving a stranded animal to deeper water is one of the main causes of death. It becomes stressed and exhausted, therefore may not survive in the sea.


What should you do upon discovering a stranded marine mammal or turtle?

1. Call port police and Archipelagos team

- Port Police (Vathi) +30 227 3027318

- Archipelagos Research Base: +30 227 3061191

- For urgent matters ONLY: +30 697 4744949

2. Check for movement from a distance.(It might be normal for a turtle or a seal to stay on a beach, therefore they may not be stranded.)

3. Do not get close to the eyes, it can distress the animal.

4. Disentangle or cut away any fishing line or net that may be around the animal.

5. Keep the animal cool and wet by continually covering it with wet sheets or towels (also seaweed if available). Cut the middle part of the towel out to avoid covering the dorsal fin

6. Never touch the blowhole or the eyes.

7. Ensure that the blowhole/nostrils are not covered and clear of water and debris.

8. Make sure the whale or dolphin lies on its underbelly and dig trenches under its pectoral fins (flippers). If possible, fill the trenches with seawater to help cool the animal.

9. In sunny weather, attempt to provide shade for the animal, ideally by raising a construction covered with tarpaulin or different type of material.

10. In cold or windy weather, attempt to provide a windbreak around the animal to prevent windburn damage.

Archipelagos provides first aid trainings to ensure that trained volunteers who can respond to strandings in an efficient and effective manner are present in different regions of Greece. For more information about these trainings, please contact us.

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