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Elena Politi

Elena Politi, biologist, has collaborated full-time with the Tethys Research Institute from 1991 to 2010.

Initially involved in data collection and analysis on dolphins in Croatia, in 1993 she founded the Ionian Dolphin Project, a long-term project on the socio-ecology of two resident coastal dolphins populations in the Ionian Greece, which she directed until 2003.

From 2003 to 2010 Elena has actively managed the Tethys Research Institute as Executive Director first and Financial Manager later on. In her career within Tethys, Elena has been involved in several research campaigns run by the Institute, including surveys in the Caribbean Sea, in the Canary Islands, in the former Spanish Sahara, and several Mediterranean areas. She is member of the Tethys Board of Director’s since 1994, and has been Tethys vice-president from 1996 to 2000.

From 2010 she has been an independent consultant as project manager in different environments, searching for new inputs for improving her skills. From October 2012 to December 2013 she worked for the European Inter-University Centre in Human Rights and Democratisation, to organise a conference and a training seminar in human rights and the environment.

Her main professional skills include a good attitude to teamwork, capability of working independently, adaptability to new situations and to different people, very good mediation ability and stress management, good sense of organisation and planning and effective communicator. During her career she gained a broad expertise in several aspects that play a crucial role in a project multi-task management, in particular with regards to the budget planning, the logistic organisation, the graphic and web design and a deep know-how of a vast range of computer software packages.

She is mainly interested in working with non-profit organisations in the field of the environment conservation and high-level education.
Supervisors: Giuseppe Notarbartolo di Sciara
Address: Venice, Italy

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Papers by Elena Politi

J. CETACEAN RES. MANAGE. , 2003

From 1991-2002 data on the presence and distribution of cetaceans in the Greek Seas have been sys... more From 1991-2002 data on the presence and distribution of cetaceans in the Greek Seas have been systematically collated in a database (821 sightings and 715 strandings). Data originated from dedicated surveys, stranding reports, opportunistic sightings and published or unpublished photographic and video documents. Twelve cetacean species have been recorded. Seven of them are permanently present and commonly observed in one or more of the Greek Seas: striped dolphin, common bottlenose dolphin, short-beaked common dolphin, Cuvier's beaked whale, sperm whale, Risso's dolphin and fin whale. In addition, the harbour porpoise is present locally in the Thracian and northern Aegean Seas. The humpback whale, false killer whale and common minke whale are occasional Mediterranean species that were sighted or stranded infrequently; the Sowerby's beaked whale is an accidental species that was found floating dead only once. Five other species (white whale, Blainville's beaked whale, long-finned pilot whale, killer whale, blue whale) have been erroneously included in the Greek cetacean fauna in the past due to wrong assumptions, false identifications or lack of supporting evidence. The occasional occurrence of pilot and killer whales in the Greek Seas should still be regarded as unconfirmed. The distributional range, stranding numbers and sighting frequencies of sperm whales, Cuvier's beaked whales and short-beaked common dolphins in the Greek Seas indicate that their local 'sub-populations' are among the most important in the entire Mediterranean Sea. Harbour porpoises in the Thracian and northern Aegean Seas are important from a conservation perspective since this species does not inhabit any other part of the Mediterranean Sea.

Journal of Biogeography, 2001

Marine Mammal Science, 1999

The diurnal behavior of a bottlenose dolphin ( Tursiops truncatus ) community was observed from s... more The diurnal behavior of a bottlenose dolphin ( Tursiops truncatus ) community was observed from small inflatable craft between 1987 and 1994. Following a preliminary ad libitum study 11,839 3‐min behavioral samples were recorded in 1991‐1994. The behavioral budget showed a predominance (about 80%) of activities characterized by long (>30 sec) dives, considered to be largely related to prey search or feeding. Obvious foraging near the surface was observed rarely. The frequent following of trawlers (accounting for 4.6% of the behavioral budget) was indicative of the presence of alternative strategies for finding food. Yearly and seasonal behavioral variation‐particularly in feeding‐related and travel behaviors‐was consistent with the hypothesis of behavioral flexibility as a response to environmental changes and fluctuating prey kind and availability. Yearly shifts in social behavior appeared to be partly influenced by breeding cycles. Groups engaged in feeding‐related activities were significantly smaller than traveling or socializing groups, and dramatic interannual group‐size shifts seemed to be largely affected by environmental variables, rather than being entirely determined by behavioral activity changes. The remarkable behavioral flexibility of this bottlenose dolphin community may contribute to its survival in the shifting environmental conditions of the northern Adriatic Sea. However, the high proportion of time consistently devoted to feeding‐related activities, as compared to other areas, suggests that food resources in the Kvarnerić were not only highly variable but also depleted.

REP. INT. WHAL. COMMN, 1998

Between 20 January and 14 February 1996, a 20 m auxiliary ketch investigated the coastal waters o... more Between 20 January and 14 February 1996, a 20 m auxiliary ketch investigated the coastal waters of Southern Morocco, a former wintering ground for right whales (Eubalaena glacialis). The aims were to: verify if right whales could still be found in the area; evaluate the environmental conditions of the region and assess its suitability as a right whale habitat; investigate the status of other cetaceans living in the area; and establish a long-term cetacean sighting and stranding reporting mechanism in cooperation with the local authorities. A 750km survey yielded no cetacean sightings except inside Dakhla Bay, where communities of bottlenose dolphins (Tursiops truncatus) and Atlantic humpbacked dolphins (Sousa teuszii) were found to coexist. Local knowledge of a regular, predictable presence of large whales in the coastal zone was lacking. The hypothesis that the area still serves as a winter concentration site for the remnants of an eastern North Atlantic right whale population, although not falsified by this study, seems rather unlikely. The dearth of cetaceans in the shelf waters of Southern Morocco, as well as the possible over-exploitation of the fishing resources in the region, may be cause for concern and warrants further investigation. Finally, with the objective of increasing baseline information on the local cetacean fauna, and particularly concerning the possibility that right whales may be sighted in the future, a procedure was established for the long-term routine reporting of cetacean sightings and strandings by the Royal Navy of Morocco to the Groupe d'Etudes des Cétacés et Pinnipèdes du Maroc, Rabat.

Quaderni Civica Stazione Idrobiologica, 1997

A total of 75 blue sharks, Prionace glauca, caught by anglers during summer 1990, were sampled, a... more A total of 75 blue sharks, Prionace glauca, caught by anglers during summer 1990, were sampled, and their stomach contents were analyzed. Although teh blue shark diet is composed by bony fishes and cephalopods, results showed that in the Adriatic Sea Prionace glauca feeds mainly on demersal prey, rather than on pelagic and mesopelagic organisms, as reported in the literature. The hypothesis that these different feeding habits reflect an adaptation to environmental factors, such water depth, seems to be correct. Samples collected in the shallow northern Adriatic showed a higher frequency of demersal preys, largely Sepioides cephalopods, compared to samples collected in the central Adriatic, where water depth ranges between 100-200 m. Moreover, the females being more abundant in the northern Adriatic, showed a prevalence of demersal preys compared to males. It is likely that these qualitative variations in their diet reflected differences in habitat use between males and females, also confirming the opportunistic feeding habits of this species. Sexual segregation in blue shark populations occurs during the breeding season. Therefore, the northern Adriatic Sea may represent a nursery area, where females migrates seasonally at the beginning of the reproductive period.

Marine Mammal Science, 1997

A bottlenose dolphin community was studied from small inflatable craft from 1987 to 1994 in a rel... more A bottlenose dolphin community was studied from small inflatable craft from 1987 to 1994 in a relatively large area (about 800 km2) east of the islands of Loˇsinj and Cres, northern Adriatic Sea. A total of 106 individuals were photoidentified based on natural permanent marks on their dorsal fins. Most of the dolphins were resighted on a regular basis, indicating a high level of year-round site fidelity, although their range was evidently greater than the chosen study area. Dolphin density was highly variable and considerably lower than for most well-known bottlenose dolphin communities. Groups averaged seven individuals, with a mode of two. Groups entirely composed of adults were the smallest, groups with calves the largest. Group fluidity was high, seasonal and yearly changes in mean group size being also considerable. Summer was the peak calving season, with a striking variation in the number of births on alternate years. Poor evidence of shark predation was found. The social organization of this dolphin community seemed to be highly flexible, possibly as an adaptation to cope with environmental changes as well as with a limited and variable availability of prey.

Frontiers in Marine Science, 2022

Important Marine Mammal Areas (IMMAs) Diversity, as well as the design and management of Marine P... more Important Marine Mammal Areas (IMMAs) Diversity, as well as the design and management of Marine Protected Areas (MPAs) and the extension of MPA networks. The Task Force is working toward completing a global network of IMMAs that will contribute the scientific information needed to fulfill the current collective goal of protecting 30% of the ocean by 2030.

Various studies on Mediterranean cetaceans have revealed bioaccumulation of contaminants such as ... more Various studies on Mediterranean cetaceans have revealed bioaccumulation of contaminants such as organochlorines (OCs) and heavy metals. The susceptibility of these animals to organic pollutants and the relationship between bioaccumulation and population decline (as in the case of Delphinus delphis) are unexplored ®elds. In this study, we used a nondestructive approach (skin biopsy) to explore OC bioaccumulation processes and mixedfunction oxidase activity (BPMO) in four species of cetaceans: striped dolphin (Stenella coeruleoalba), bottlenose dolphin (Tursiops truncatus), common dolphin (D. delphis) and ®n whale (Balaenoptera physalus). Signi®cant dierences in BPMO induction and OC levels were found between odontocetes and mysticetes, the former having mixed-function oxidase activities four times higher than the latter, binding with levels of OCs one order of magnitude higher in odontocetes. A signi®cant correlation (P<0.05) between BPMO activities and OC levels was found in B. physalus. In an ongoing project, ®broblast cultures have been used as an alternative in vitro method of evaluating interspecies susceptibility to contaminants such as OCs and polycyclic aromatic hydrocarbons (PAHs). These results suggest that cetacean skin biopsies are a powerful non-invasive tool for assessing ecotoxicological risk to Mediterranean marine mammals species.

Bottlenose dolphins are the only cetaceans regularly observed in the northern Adriatic Sea, but t... more Bottlenose dolphins are the only cetaceans regularly observed in the northern Adriatic Sea, but they survive at low densities and are exposed to significant threats. This study investigates some of the factors that influence habitat use by the animals in a largely homogeneous environment by combining dolphin data with hydrological and physiographical variables sampled from oceanographic ships. Surveys were conducted year-round between 2003 and 2006, totalling 3,397 km of effort. Habitat modelling based on a binary stepwise logistic regression analysis predicted between 81% and 93% of the cells where animals were present. Seven environmental covariates were important predictors: oxygen saturation, water temperature, density anomaly, gradient of density anomaly, turbidity, distance from the nearest coast and bottom depth. The model selected consistent predictors in spring and summer. However, the relationship (inverse or direct) between each predictor and dolphin presence varied among seasons, and different predictors were selected in fall. This suggests that dolphin distribution changed depending on seasonal forcing. As the study area is relatively uniform in terms of bottom topography, habitat use by the animals seems to depend on complex interactions among hydrological variables, caused primarily by seasonal change and likely to determine shifts in prey distribution.

Mammal …, 2003

The recent decline in the Mediterranean population of short-beaked common dolphins Delphinus delp... more The recent decline in the Mediterranean population of short-beaked common dolphins Delphinus delphis has been the subject of scientific controversy and political indifference. Research on these animals has been very limited and there has been no large-scale, systematic effort to assess and monitor their abundance and distribution. The consequent lack of data has prevented a good understanding of historical and ongoing trends. 2. Nonetheless, literature and osteological collections confirm that common dolphins were widespread and abundant in much of the Mediterranean Sea until the late 1960s and that their decline occurred relatively quickly. Today, common dolphins remain relatively abundant only in the westernmost portion of the basin (Alboràn Sea), with sparse records off Algeria and Tunisia, concentrations around the Maltese islands and in parts of the Aegean Sea, and relict groups in the southeastern Tyrrhenian and eastern Ionian Seas. Otherwise, these dolphins are rare in, or completely absent from, Mediterranean areas where information is available. 3. Circumstantial evidence and qualitative judgements by the authors suggest that the following factors may have contributed to the decline of common dolphins: reduced availability of prey caused by overfishing and habitat degradation; contamination by xenobiotic chemicals resulting in immunosuppression and reproductive impairment; environmental changes such as increased water temperatures affecting ecosystem dynamics; and incidental mortality in fishing gear, especially gillnets. The cumulative importance of these factors is poorly understood, and as a result, few conservation measures have been implemented. 4. This paper reviews current knowledge and suggests priorities for action aimed at identifying and mitigating the main threats to common dolphins in the Mediterranean, with the ultimate goal of restoring the species' favourable conservation status in the region.