The Tethys Research Institute (official name: Istituto Tethys ONLUS) is a non-profit research organisation founded in 1986 to support marine conservation through science and public awareness and by participating in the international conservation process. Tethys' activities are mainly carried out in the Mediterranean Sea, although research programmes have been conducted also in the Black Sea, the North Atlantic Ocean, the Caribbean, the Red Sea and Antarctica. The results of these activities have been presented in scientific publications as well as in meetings, workshops and conferences.
Mission statement
Tethys' mission is the conservation of the marine environment and its biodiversity, by supporting national and international marine conservation policies and processes with robust scientific knowledge, and by developing, promoting and implementing public awareness and education activities.
History
The Tethys Research Institute was founded in Milan, Italy, on 31 January 1986 by marine ecologist Giuseppe Notarbartolo di SciaraNotarbartolo di Sciara, G (2012). "Historical perspectives. Ancient waves, recent concerns: the budding of marine mammal conservation science in Italy". Aquatic Mammals. 38 (4): 441–455. doi:10.1578/AM.38.4.2012.441 and Egidio Gavazzi, at the time the publisher of the Italian magazine AQVA. The organisation's name was inspired by a figure of Greek mythology, the sea goddess Tethys, daughter of Uranus and Gaia and wife of Oceanus. The Mediterranean Sea is the modern remnant of the prehistoric Tethys Ocean. Since 1995 the institute's headquarters have been established in the premises of the Civic Aquarium of Milan, on the basis of an agreement with the City Council.
Since its foundation, Tethys has promoted research activities on marine mammals, such as cetaceans (whales and dolphins) and the endangered Mediterranean monk seal, although investigations have also extended to devil rays and sea turtles. Over more than three decades of work, Tethys has generated one of the largest datasets on Mediterranean cetaceans. Tethys shares its data with the scientific community and policy makers through several open access platforms such as OBIS, OBIS-SEAMAP, GBIF, EMODNET, and INTERCET.
Research programmes and techniques
Research methods include distance sampling surveys (both from aircraft, drones and vessels) capture-recapture techniques based on long-term photo-identification to estimate population abundance; habitat and distribution time-series studies inclusive of the collection of remotely sensed environmental covariates, bioacoustics, behavioural sampling, remote biopsy sampling for genetic and toxicological analyses, passive tracking techniques, as well as radio and satellite telemetry.
Since 1987 Tethys has been carrying out cetacean surveys in the waters surrounding Italy and adjacent countries. Early boat-based surveys generated the first estimate of relative abundance in the central Mediterranean Sea highlighting the great importance of the Ligurian Sea for whales and dolphins, in comparison to other sectors of the Mediterranean.Notarbartolo di Sciara G., Venturino M.C., Zanardelli M., Bearzi G., Borsani F.J., Cavalloni B. 1993. Cetaceans in the central Mediterranean Sea: distribution and sighting frequencies. Bollettino di Zoologia (Italian Journal of Zoology) 60:131-138. This was the first indication of the need for the establishment of a cetacean protected area in the North -Western Mediterranean, leading to the proposition of an international sanctuary there, the Pelagos Sanctuary for Mediterranean Marine Mammals.
Since 2009, Tethys has carried out a series of seasonal aerial surveys funded by the Italian Ministry of the Environment and Protection of Land and Sea (MATTM), in cooperation with the International Whaling Commission (IWC) and the Institute for Environmental Protection and Research (ISPRA), to estimate the density and abundance, and monitoring the distribution of cetaceans and other marine mega-vertebrates in the seas around Italy. The surveyed areas included the Ligurian Sea, the Central and Southern Tyrrhenian Sea, portions of the Seas of Corsica and Sardinia, as well as the Ionian Sea and the Gulf of Taranto.
Research is focussed also on collisions between whales and large ships in the Mediterranean and especially in the Pelagos Sanctuary. A study financed by the Permanent Secretariat of the Pelagos Agreement and published in September 2020 (Proposal to develop and evaluate mitigation strategies to reduce the risk of ship strikes to fin and sperm whales in the Pelagos Sanctuary) was carried out in collaboration with British Antarctic Survey, International Fund for Animal Welfare, QuietOceans, Souffleurs d'Ecume, WWF France. Tethys is also a partner in LIFE-SEADETECT, a European collaborative project aimed at reducing the issue of collisions with marine mammals (2022–2026).
Long-term research projects
Adriatic Dolphin Project Tethys has implemented long-term research programmes on Mediterranean marine mammals. The oldest of these, the Adriatic Dolphin Project (ADP), based on the island of Lošinj (Croatia), was run by Tethys from 1987 to 1999, and produced a large body of substantive ecological knowledge on the local population of common bottlenose dolphins (Tursiops truncatus). Concern for the survival of this dolphin population, threatened mainly by a very high level of small vessel traffic during summer, prompted the institute to propose the establishment of a local dolphin protected area. Upon the decision by Tethys to terminate the ADP in 1999, the baton of the scientific and conservation work on the local dolphins was passed to former ADP researchers, founders and co-founders of the Blue World Institute, a Croatian NGO.
Cetacean Sanctuary Research The Cetacean Sanctuary Research (CSR) project, established in 1990, is Tethys' second long-term project. It is carried out within the waters of the Pelagos Sanctuary for Mediterranean Marine Mammals, mostly in the Ligurian Sea. The core study area extends over about 25,000 km2, encompassing coastal, slope and pelagic waters between continental Italy and France, and the Island of Corsica. The CSR target species are fin whale (Balaenoptera physalus), sperm whale (Physeter macrocephalus), long-finned pilot whale (Globicephala melas), Risso's dolphin (Grampus griseus), Cuvier's beaked whale (Ziphius cavirostris), striped dolphin (Stenella coeruleoalba), common bottlenose dolphin (Tursiops truncatus) and short-beaked common dolphin (Delphinus delphis). The project focuses on population dynamics, spatial distribution, habitat preferences, behaviour, bioacoustics, photogrammetry, genetics, as well as on the evaluation of long-term environmental changes and monitoring of anthropogenic pressures. The main aim is to produce scientific knowledge to support the conservation of marine mammals.
Studies conducted within the CSR project generated one of the longest time series and one of the largest datasets on Mediterranean cetaceans, allowing to evaluate and detect changes in the species' presence. The data series on Risso's dolphins, among the longest and one of the most important of its kind, allowed to highlight a dramatic decline of this species in the study area.Azzellino, A., Airoldi, S., Gaspari, S., Lanfredi, C., Moulins, A., Podestà, M., Rosso, M. and Tepsich P. 2016. Risso's Dolphin, Grampus griseus, in the Western Ligurian Sea: Trends in Population Size and Habitat Use. In: G. Notarbartolo Di Sciara, M. Podestà and B.E. Curry (eds), Advances in Marine Biology 75: 205- 223, Academic Press.Airoldi S., Azzellino A., David L, Dhermain F, Di-Meglio N., Jimenez V, Jourdan J, Lanfredi C, Remonato E, Rosso M, Roul M, Scuderi A. 2015 Report Finale del progetto "Absolute abundance of Risso's dolphin (Grampus griseus) in the north-western part of the Pelagos Sanctuary". Pelagos Sanctuary Convention No. 03/2014, 59 pages. This result significantly contributed to having the Risso's dolphins Mediterranean subpopulation listed as Endangered in the IUCN Red List of Threatened species.Lanfredi, C .., Arcangeli, A., David, L., Holcer, D., Rosso, M. & Natoli, A. 2021. Grampus griseus (Mediterranean subpopulation). The IUCN Red List of Threatened Species 2021:e.T16378423A190737150. doi:10.2305/IUCN.UK.20 21 3.RLTS.T16378423A190737150.en
Habitat preferences of cetaceans living in the Pelagos Sanctuary have been described, allowing also to make predictions of the presence probability of the different species.Azzellino, A.; Airoldi, S.; Gaspari, S.; Nani, B. (2008). "Habitat use of cetaceans along the continental slope and adjacent waters in the Western Ligurian Sea". Deep-Sea Research Part I. 55: 296–323. doi:10.1016/j.dsr.2007.11.006.Azzellino, A.; Panigada, S.; Lanfredi, C.; Zanardelli, M.; Airoldi, S.; Notarbartolo; Sciara, G. (2012). "Predictive habitat models for managing marine areas: spatial and temporal distribution of marine mammals within the Pelagos Sanctuary (Northwestern Mediterranean Sea)". Ocean and Coastal Management. 67: 63–74. doi:10.1016/j.ocecoaman.2012.05.024.
This information is critical for the management of the Pelagos Sanctuary as it enables vulnerability assessments of marine areas with respect to the existing human pressures. Furthermore, data on the variability of cetaceans' habitat preferences can be used as a basis for the evaluation of the environmental quality of marine ecosystems, as required by the Marine Strategy Framework Directive.Azzellino, A.; Fossi, M.C.; Gaspari, S.; Lanfredi, C.; Lauriano, G.; Marsili, L.; Panigada, S.; Podestà, M. (2014). "An index based on the biodiversity of cetacean species to assess the environmental status of marine ecosystems". Marine Environmental Research. 100: 94–111. doi:10.1016/j.marenvres.2014.06.003. PMID 25016937.
The CSR project has many longstanding and profitable collaborations with national and international organisations and research institutes across the Mediterranean. The analyses and the large photographic catalogues shared among institutes allowed to study both short and long-term movements of cetaceans in the Western Mediterranean. It has been observed that Risso's dolphins and common bottlenose dolphins can cover hundreds of km; sperm whales, over a thousand km, moving from the Strait of Gibraltar to the Ligurian Sea.
Cetaceans' vocalisations are regularly recorded, generating a large acoustic dataset and allowing studies of the vocal repertoire of sperm whales and other species.Pace, D.S., Lanfredi, C. C., Airoldi, S., Giacomini G., Silvestri, M., Pavan, G., & D. Ardizzone. Trumpet sounds emitted by male sperm whales in the Mediterranean Sea. Scientific Report 11, 5867.2021 . do i .org/10.1038/s41598 021 84126 Behaviour and overall body size could also be inferred from acoustic data in sperm whales.
Research on cetaceans in the Pelagos Sanctuary also revealed an unexpected genetic separation between fin whales occurring in the Ligurian Sea and their North Atlantic conspecifics. Studies based on mtDNA analysis show that the Mediterranean Risso's Dolphin population has been found to be genetically differentiated from the one inhabiting the waters of Azores, United Kingdom and from other oceanic populations. There is also some evidence of a possible Mediterranean subpopulation.Gaspari S, Airoldi S, Hoelzel AR. 2007. Risso's dolphins (Grampus griseus) in UK waters are differentiated from a population in the Mediterranean Sea and genetically less diverse. Conservation Genetics 8(3): 727-732.