O2_Mediterranean cetaceans

Ecosystem services provided by cetaceans in the Mediterranean.

Lead Author: UBO
Contributors: Evangelia Drakou (UBO), Linwood Pendleton (UBO), Ward Appeltans (UNESCO)


Our storyline focuses on the entire Mediterranean LME, but we will also downscale our approach/models in selected MPAs like the Pelagos sanctuary. Other candidate areas of focus are those that form part of the ACCOBAMS agreement shown in the map below (source: http://www.pelagosinstitute.gr/en/MPAs/).



We will focus our efforts on using Earth Observation along with in situ data to assess the state of the tourism based on whale watching in the Mediterranean by measuring three major types of variables: variables assessing the state of the cetacean population in the Mediterranean, the major drivers of change in their population density (human and ecological e.g. SST changes and impacts of fishing) and variables that assess the benefits to the human population living by these areas, like benefits from tourism and whale watching activities.

The presence of large cetaceans like whales can be monitored from space (Fretwell et al., 2014). Most of the current efforts have been focusing in US waters while in the Mediterranean this is more challenging due to the quality of the data resolution, the species’ diving time and climatic conditions. In situ data can be collected by the work done by two large research institutes in the Mediterranean, the Tethys (http://www.tethys.org/tethys/) and Pelagos (http://www.pelagosinstitute.gr/) institutes.

The main cetaceans present in the Mediterranean are listed in the table below (information on distribution is given at the IUCN report: http://cmsdata.iucn.org/downloads/status_distr_cet_blac_med.pdf)


Cetacean list

Geographical distribution in the Mediterranean

Long-finned pilot whale

Western Mediterranean mostly

Rare around Greece


North and East of Balearic Islands and Ionian Sea mostly

Short-beaked common dolphin

Large communities in the Ionian Sea, but in general all over Med

Risso’s dolphin

Common in the Med from the Gibraltar area to Aegean Sea

Humpback whale

Few records in the Med around Aegean

Killer whale

Mostly western Med (Gibraltar, Morocco, Spain, France, Italy, Malta)

Sperm whale

Widely distributed in the Med from Alboran Sea to Levant basin Algerian-Ligurian Basin, Tyrrhenian and Ionian Sea, off southern Crete and possibly all along the Aegean Arc; predictably present in the North Aegean Sea

Striped dolphin

The most common pelagic cetacean in the Med.

Common bottlenose dolphin

All around the Med, mostly in Alboràn, Balearic, and Adriatic

Seas, the Tunisian and Malta Plateaus, the Aegean Sea, the Turkish straits system and other areas of the continental shelf, including Algerian coastal waters and possibly Middle-East Mediterranean waters.


Cuvier’s beaked whale




Main threats: Overfishing, underwater noise, fisheries bycatch, plastic debris (the complete list is in the table below)

The major drivers that change the population of these species are either climatic (affecting mostly the species habitat) or those coming from the fishing industry. The presence of big fishing vessels causes deaths of the species’ being involved to boat strikes, they might be caught as fisheries bycatch or the overfishing might reduce their forage. The main human and environmental drivers that affect the cetacean populations and their effects are also listed in the table below. The list is not exhaustive and will be updated throughout the project duration.


Drivers of change in cetacean population

Effect on Cetaceans

Temperature Change

Loss of Forage, population decline, migration

Salinity change


Overfishing (incl habitat destruction)


Shipping industry

Strikes and death

Fisheries bycatch


Underwater noise (sonar, military exercises etc)

Animal health, death

Contaminants (organochlorine compounds, heavy metals, selenium, xenobiotic chemicals)

Animal health

Prey depletion


Plastic debris

Animal health and death

Biological invasions



The impact these drivers of change might have on whale watching tourism, as an ecosystem service provided by these species populations will be assessed. The above-mentioned parameters along with socio-economic variables, such as tourism revenues, records of sailing/recreational boats and visitor counts will be used for that. For all types of information both in situ and earth observation measurements will be combined to give us estimates for the tourism ES supply and demand. Throughout this process we will identify essential variables (EVs) that can be used for these measurements, by selecting either from the already proposed ones or by generating new ones.


Click here to download the storyline presentation.