Northern Sporades Research Articles

The herpetofauna of the Sporades Islands (Aegean Sea, Greece): New discoveries and a review of a century of research

The Sporades are one of the most biologically important archipelagos in the Aegean Sea (Greece) and have received priority conservation over the last 50 years. However, despite numerous early efforts, its herpetofauna is only partially described, resulting in many distributional gaps that have prevented adequate understanding and management of the resident species communities. We review one century of bibliography from the Northern Sporades and combine this information with a review of museum specimens and insights from numerous extensive field surveys over the last near-decade to provide for the first time a comprehensive picture of the reptiles and amphibians of the archipelago. We report here on 26 new island records and find that the herptile communities of the region are largely derived from the herpetofauna of the nearby Thessaly mainland, with only a few introduced taxa. There is also a small but significant set of endemic taxa in the archipelago. Island species richness declines with decreasing island size and increasing duration of island isolation. Herptile communities on smaller islands are progressively nested subsets of the communities on larger islands. The presence of reptile species depends sensitively on the condition and management of native ecosystems. While non-aquatic species maintain largely healthy populations, most populations are under pressure from the combined effects of rampant tourist development, the destruction and degradation of rare wetland habitats, and the abandonment of traditional agricultural landscapes. We provide recommendations regarding sustainable management of the local reptile and amphibian populations.

Sociocultural valuation of human impacts on marine ecosystems: the case of the National Marine Park of Alonissos in Greece

ABSTRACT Conservation priority ecosystem components provide multiple ecosystem services. However, different human activities have placed significant pressures on marine ecosystems and the biodiversity they support, resulting in the degradation of the respective services. In the present study, we combine a choice experiment for the valuation of related ecosystem services with the Cumulative Impact Assessment method, to estimate the value of human impacts on three conservation priority habitats (the seagrass meadows, the gorgonian forests and the coralligenous reefs) of the National Marine Park of Alonissos Northern Sporades in Greece. The results indicate significant values and thus raise flags for more effective decisions related to environmental policies, such as the Programmes of Measures under the Marine Strategy Framework Directive.

Population Status and Colony Characteristics of Eleonora’s Falcon (Falco eleonorae) in the National Marine Park of Alonissos—Northern Sporades, Greece

Eleonora’s Falcon is the commonest bird of prey in Greece, with more than 80% of the global population breeding on Greek islands. The aim of this study was to assess the population status and the colony characteristics for the species in the National Marine Park of Alonissos—Northern Sporades. Every island was circumnavigated twice in order to count individual birds and active nests during the breeding season of the species in 2021 by boat. Colony characteristics including nest category, nest height above sea level and nest orientation were recorded. The species was recorded nesting in 13 (12 uninhabited and 1 inhabited) out of 29 islands involving a total of 329 active nests. Most nests were in cliff cavities located between 12 m and 400 m above sea level, and had predominantly north-westerly and westerly orientations. These findings may inform conservation management decisions including minimization of disturbance in colonies, safeguarding colonies under threats, eradicating invasive species and protecting and enhancing the breeding habitat of the species in the specially protected area of the National Marine Park of Alonissos—Northern Sporades.

Stakeholder views on environmental protection policies in the National Marine Park of Alonissos Northern Sporades, Greece

The prospect of many species or unique landscapes disappearing from the planet has resulted in the mobilization of humanity to take measures against this catastrophic course. Thus, efforts are currently being made to organize action worldwide to preserve biodiversity and protect natural ecosystems. The institutionalization of Protected Areas aiming at the protection and management of biodiversity as well as the conservation of areas with particular natural beauty and special characteristics is an opportunity for sustainable development that respects nature and humans and leaves natural resources as a legacy to future generations. According to a recent European Union directive, National and local authorities and coastal communities should be involved in the design and management of the Marine Protected Areas. This paper aimed to improve the governance of the National Marine Park of Alonissos Northern Sporades through a face-to-face questioner conducted to the residents, hunters and fishermen of the northern Sporades islands. All social groups desire to participate in decision-making processes regarding the marine park. Unlike hunters and fishermen, the local community requests the expansion of the marine park. Stakeholders have good knowledge of park issues and they were updated mainly by the internet, the social network, and the hunting/fishing associations. Most residents have neutral to negative opinion about the management body of the park. Proposals concerning the protection, development and promotion of the marine park were highly appraised except those related to leisure boat docking infrastructures.

Conservation status of upper-mesophotic octocoral habitats at Sporades Archipelago (Aegean Sea)

Octocoral forests created by the yellow sea fan Eunicella cavolini and the red sea fan Paramuricea clavata were studied at the National Marine Park of Alonissos Northern Sporades (Aegean Sea, Greece), between 30 and 45 m depth, in order to assess their conservation status and the occurrence of both natural and anthropogenic stressors. The area was characterized by rich and dense coral forests, with densities up to 55.2 colonies m−2 for E. cavolini and 28.0 colonies m−2 for P. clavata. The coral population showed signs of stress, although mortality was low. A combination of stressors linked to global warming and fishing impacts, including macroalgal epibiosis, tip necrosis, increasing coral feeders, and abandoned fishing gears, could impair the status of these habitats in the near future. Although the effects of climate change are global, local conservation actions may reduce direct anthropogenic impacts and enhance habitats' resilience.

Agios Petros and the Neolithic pottery-making traditions of the deserted islands, Northern Sporades, Greece

The Neolithic sites of the Cyclops Cave and Agios Petros provide insights into a once flourishing culture that inhabited the ‘Deserted Islands’ of the northern Sporades in the Greek north Aegean. Building on scientific analysis of ceramics from the seasonally inhabited Cyclops Cave, the present study examines in detail 39 sherds from the permanently settled site of Agios Petros on the adjacent island of Kyra Panagia, using a combination of thin section petrography, geochemistry, scanning electron microscopy and X-ray diffraction. The two ceramic assemblages have been directly compared, revealing close similarities and differences that provide insights into the relationship between the neighbouring sites and their functions. The chaîne opératoire of the dominant local pottery-making tradition of the Deserted Islands is reconstructed and its implications for the identity of the Agios Petros-Yioura/Northern Sporades Culture are considered.

Study of the Spatiotemporal Variability of Oceanographic Parameters and Their Relationship to Holothuria Species Abundance in a Marine Protected Area of the Mediterranean Using Satellite Imagery

Marine protected areas (MPAs) are designated to protect marine ecosystems and, among other things, to monitor climate variability, which in turn affects aquatic species. The aim of this study is to examine the contribution of remotely sensed data as an indication of Holothuria abundance, by investigating the spatiotemporal variability of physicochemical parameters. The study area is in the National Marine Park of Alonissos Northern Sporades, which is included in the NATURA 2000 network. Firstly, the abundance of Holothuria species was measured by scuba diving. At the same time, depth profiles of five physicochemical parameters (temperature, salinity, pH, dissolved oxygen and Chl-a) were recorded by CTD (conductivity, temperature, depth), a primary instrument used to determine the essential physical and chemicals properties of seawater column profiles in the coastal zone. The physicochemical variables examined are the most common environmental parameters with the highest impact on growth, reproduction, productivity and survival rate of sea cucumber species, affecting the availability of food sources. Analysis of this data allows us to identify parameters which are essential for their existence. The analysis showed that only temperature and Chlorophyll-a (Chl-a) could be useful for identifying the abundance. These two parameters are readily available from satellite data. Additionally, particulate organic carbon (POC) is essential for Holothuria’s existence. Consequently, a time series of satellite data products from Terra/MODIS sensor were utilized from 2000 to 2020 for sea surface temperature (SST), Chl-a and POC. The monthly temporal trend shows that the abundance could be justified in areas where the Holothuria presence has been established. Monthly spatiotemporal analysis shows that SST, Chl-a and POC availability, could be an indication of the differences in abundance recorded.

Strain localization during burial and exhumation of the continental upper crust: A case study from the Northern Sporades (Pelagonian thrust sheet, Greece)

Abstract Extension is a key process controlling the post-orogenic exhumation of metamorphic rocks in subduction and collision zones. Previous studies have largely focused on the mechanics of localized core-complex style post-orogenic extension and the large-scale effects of various internal (e.g. rheology) and external (e.g. plate motions) parameters on the mode of extension. However, many regions on earth underwent rock exhumation during post-orogenic extension, which is characterized by distributed rather than localized deformation. We explore conditions of distributed deformation as illustrated by the Pelagonian unit in the Aegean subduction system. In particular, we explore the influence of structural inheritance related to the pre-extension shortening and mechanical stratigraphy on the localization of extension on the scale of the upper crust through detailed structural analysis on the islands of Skiathos and Skopelos. Additionally, the time frame of deformation has been established by 40Ar/39Ar dating of key shear zones. Shortening on the islands predominantly took place by ductile top-SW thrusting under low-grade metamorphic conditions, localized in weak calcite marble layers within the Upper Cretaceous and Upper Triassic carbonates at ~55 Ma. We show that the presence of shallow decoupling levels in the upper crust resulted in the formation of thin (several 100 m thick) thrust sheets that are defined for the first time on Skiathos. The Early Paleogene accretion of the Pelagonian upper crust to the upper plate (Eurasia/Rhodopia) was followed by the extensional inversion of the nappe stack. Extension was accommodated by opposite-sense, generally top-NE, ductile to brittle shearing, which localized at inherited heterogeneities such as reverse-sense shear zones and stratigraphic contacts at around 35 Ma, as suggested by our 40Ar/39Ar age spectra. The dense network of such northerly-dipping, inherited weakness zones resulted in a highly distributed pattern of extensional deformation dominated by layer-parallel shearing. We argue that the distribution of crustal heterogeneities substantially influences the style of post-orogenic extension.

Taxonomic and phylogenetic diversity patterns in the Northern Sporades islets complex (West Aegean, Greece)

The Aegean archipelago has long been the main research area of numerous biogeographers, plant ecologists and taxonomists due to its intricate palaeogeography and high environmental and topographical heterogeneity. Nevertheless, some parts of this archipelago are essentially unexplored and the processes driving spatial variation in species composition remain unaddressed. Aiming to fill these gaps, we investigated the flora and plant diversity patterns of the Northern Sporades island group, as well as its biogeographical relationships. The study area lies in the biogeographical region of the West Aegean islands and comprises 23 islands and islets. The total flora of the study area consists of 1202 infrageneric taxa, belonging to 517 genera and 120 families, reflecting its geographical and bioclimatic characteristics. The endemic element consists of 41 taxa (3.4% of the flora), eight of which are restricted to the West Aegean islands and two are single island endemics. Area emerged as the most important variable in shaping plant species richness, while niche-based processes played a lesser role in driving these patterns. Regarding the taxonomic and phylogenetic beta-diversity patterns, environmental filtering and not dispersal limitation seems to shape the plant assemblages of the Northern Sporades islets. Biogeographically, the Northern Sporades island group seems to be closer connected to the Kiklades rather than to Evvia or the adjacent mainland, due to their longer isolation and separate palaeogeographical history during the Quaternary.

Cretaceous‐Paleogene Tectonics of the Pelagonian Zone: Inferences From Skopelos Island (Greece)

AbstractWe have investigated subduction‐exhumation processes in the Pelagonian zone, exposed on the Northern Sporades islands (Aegean Sea) related to successive episodes of ocean continent and continent‐continent convergence through integrating multiscale structural analysis, metamorphic petrology, and white mica 40Ar/39Ar dating. Two major progressive phases of ductile deformation are documented, which are related to distinct episodes of tectonic burial and exhumation of the Pelagonian continental margin, which was facing the Neotethys/Vardar ocean. Review of existing data sets from neighboring regions shows that both deformation phases can be correlated along strike up to the Dinarides. The first phase of tectonic burial and exhumation (D1) is characterized by NW‐SE tectonic transport, greenschist facies metamorphism, and Early Cretaceous (~105‐135Ma) 40Ar/39 Ar white mica single fusion ages. D1 is correlated with the initial closure of the Vardar ocean by top‐to‐the‐W to NW ophiolite obduction and the underthrusting of the Pelagonian margin below the oceanic upper plate. Underthrusting was followed by exhumation and the deposition of Late Cretaceous‐Paleogene sediments. The second phase of burial and exhumation (D2) is characterized by NE‐SW tectonic transport, greenschist to blueschist facies metamorphism, and latest Cretaceous‐Early Eocene 40Ar/39 Ar white mica ages of S2 fabrics. Top‐to‐the‐SW shearing is correlated with the tectonic burial of the Pelagonian zone below the Eurasian continent (Rhodopia), while top‐to‐the‐NE shearing is attributed to subsequent extensional exhumation. D2 fabrics record low‐grade P‐T conditions suggesting that the decoupled cover formations exposed on Skopelos were incorporated in an accretionary wedge that formed above the subducting Pelagonian basement during Paleogene times.

Stakeholder engagement for sustainable development and their suggestions for environmental policy: The case of Mediterranean monk seal

AbstractThis study primarily attempts to understand people's beliefs toward marine protected areas considering as a case study the National Marine Park of Alonissos, Northern Sporades in Greece in order to achieve its sustainability. Specifically, it aims to identify people's opinion about the utility of the park investigating also their beliefs in relation to socioeconomic characteristics. For this reason, a face‐to‐face survey of 200 randomly selected residents and visitors of the area was carried out. The research was structured according to the principles of the contingent valuation method. According to the empirical findings, the majority of respondents recognized the contribution of the park to preserve the monk seal and the natural environment. Moreover, they want the maintenance of the park and more specialized protection measures in the area.

Kostas Mavrikis, These Scattered Isles: Alonnisos and the Lesser Northern Sporades (edited and translated with additional research by Anthony Hirst). Abingdon: Oxford Maritime Research, 2010. Pp. 478.

Kostas Mavrikis, These Scattered Isles: Alonnisos and the Lesser Northern Sporades (edited and translated with additional research by Anthony Hirst). Abingdon: Oxford Maritime Research, 2010. Pp. 478. - Volume 38 Issue 1

People and the Mediterranean Monk Seal (Monachus monachus): A Study of the Socioeconomic Impacts of the National Marine Park of Alonissos, Northern Sporades, Greece

2 MOm/Hellenic Society for the Study and Protection of the Monk Seal, Solomou Street 18, 10682 Athens, Greece Abstract The National Marine Park of Alonissos, Northern Sporades (NMPANS) in Greece is one of the few areas worldwide dedicated to the protection of the critically endangered Mediterranean monk seal (Monachus monachus). The impacts of the establishment of this protected area on the local monk seal population have been thoroughly docu- mented for the last 20 y; in contrast, little is known of the socioeconomic impacts from the establish- ment of the park on the residents of the island of Alonissos. The aim of this study was to record, using a methodological approach based on Social Impact Assessment, the attitudes of residents and visitors of Alonissos and to assess the social and economic impacts generated by the establishment and management of the NMPANS. The majority of the residents of Alonissos acknowledged the importance of the marine park in promoting the public image of the island, a fact they believed had not yet resulted in major improvements to their livelihood. They believed that the establish- ment of the park had led to considerable economic losses to the local fishing industry and expressed concerns on the effects of the park on the local human social structure and traditions. Positive effects were detected primarily from the tour- ism sector. Visitors to Alonissos valued the area for its natural beauty but were disappointed by the lack of coordinated effort to promote these natural resources. Based on the findings of this study, we conclude that the NMPANS has been generally successful in meeting its biodiversity goals but considerably less effective in attaining basic measures of socioeconomic success. If the population's socioeconomic expectations from the establishment of the park are to be fulfilled, the newly established management body of the park must improve communication and establish

On the Settlement Complex of Central Greece: An Early Nineteenth-century Testimony

No abstract

Communicating a Marine Protected Area Through the Local Press: The Case of the National Marine Park of Alonissos, Northern Sporades, Greece

Local distrust for Marine Protected Area (MPA) managers is emerging as an important factor obstructing the fulfillment of MPA objectives, and, thus, there is a need to develop a means of enhancing relationship building between MPA managers and local people. We used the National Marine Park of Alonissos, Northern Sporades (NMPANS), Greece, as a relevant case-study to investigate whether the local print media's framing of the marine park and its management affected locals' attitudes. We conducted a longitudinal review of local newspaper articles pertaining to the NMPANS during 1980-2008, and we conducted telephone interviews with local people. We found that salience of the NMPANS in the local print media remained limited and sporadic, the main stakeholder remained the centralized public sector, and the regional print media was rather detached, moderate, and largely supportive of the NMPANS throughout 1980-2008. The progression of the management periods of the NMPANS, however, was accompanied by increased importance of the NMPANS, increased deviance from conservation as the chief objective of the NMPANS's establishment, a shift from presenting facts to presenting reactions, and a shift from a positive to a mixed image of the NMPANS. Locals who relied on newspapers for local news were better informed about the NMPANS, more likely to accept the NMPANS, and more likely to participate in meetings regarding the NMPANS regardless of gender, age, and occupation than those who did not rely on newspapers. The local print media may be utilized as a free-choice learning vehicle to enhance the value of an MPA among local people and to enhance the development of trust between park managers and locals through a proactive, empowering, and cognitive media strategy.

A probabilistic seismic hazard assessment for Greece and the surrounding region including site-specific considerations

A probabilistic approach was applied to map the seismic hazard in Greece and the surrounding region. The procedure does not require any specification of seismic sources or/and seismic zones and allows for the use of the whole seismological record, comprising both historical and instrumental data, available for the region of interest. The new seismic hazard map prepared for Greece and its vicinity specifies a 10% probability of exceedance of the given Peak Ground Acceleration (PGA) values for shallow seismicity and intermediate soil conditions for an exposure time of 50 years. When preparing the map, the new PGA attenuation relation given by Margaris et al. (2001) was employed. The new map shows a spatial distribution of the seismic hazard that corresponds well with the features of shallow seismicity within the examined region. It depicts the level of seismic hazard in which the exceedance of the PGA value of 0.25 g may be expected to occur within limited areas. The highest estimated levels of seismic hazard inside the territory of Greece are found in the Northern Sporades Islands, where PGA values in excess of 0.50 g are reached at individual sites, and in the Zante Island in Western Greece, where PGA values in the range of 0.35 g to 0.40 g are obtained at more numerous localities. High values are also observed in the sea between the Karpathos and Rhodes islands, near the Island of Amorgos (Cyclades Archipelago) and in the Southwestern Peloponnesus. The levels of seismic hazard at the sites of seven Greek cities (Athens, Jannena, Kalamata, Kozani, Larisa, Rhodes and Thessaloniki) were also estimated in terms of probabilities that a given PGA value will be exceeded at least once during a time interval of 1, 50 and 100 years at those sites. These probabilities were based on the maximum horizontal PGA values obtained by applying the design earthquake procedure, and the respective median values obtained were 0.24 g for Athens, 0.28 g for Jannena, 0.30 g for Kalamata, 0.21 g for Kozani, 0.24 g for Larisa, 0.43 g for Rhodes and 0.35 g for Thessaloniki. The probabilities of exceedance of the estimated maximum possible PGA value were also calculated for the cities to illustrate the uncertainty of maximum PGA assessment.

Thessaly with the Northern Sporades

Thessaly with the Northern Sporades

Integrating Conservation and Development at the National Marine Park of Alonissos, Northern Sporades, Greece: Perception and Practice

Available information on the socioeconomic implications of marine protected areas (MPAs) for the socioculturally diverse Mediterranean region is scant. The National Marine Park of Alonissos, Northern Sporades (NMPANS), Greece was established in 1992 as a foundation for the conservation of the endangered Mediterranean monk seal Monachus monachus. The evolution of the degree of acceptance of and satisfaction from the NMPANS by involved stakeholder groups (fishermen, tourism operators, hoteliers and owners of rooms to let, governmental bodies, nongovernmental bodies, students, domestic and foreign tourists) were investigated 13 years after its establishment using written questionnaires delivered during personal interviews. The initial positive attitude of local professionals for the NMPANS has eroded due to the unsatisfactory fulfillment of expectations for socioeconomic development. Fishermen expressed dissatisfaction with, mistrust toward, and a reluctancy to communicate with the NMPANS's management body. They believe that the fishery areas have decreased in actual geographic area because of the prohibitive measures; fish stocks are declining; compensation for damage to fishery equipment by the Mediterranean monk seal and for the prohibitive measures should be provided; and stricter enforcement of regulations should take place. On the other hand, tourism operators, who organize trips for tourists to the NMPANS, unanimously reported direct economic benefits. Furthermore, there was a disparity in the perception of socioeconomic benefits derived from the NMPANS between governmental bodies and local stakeholders. The governmental bodies and the nongovernmental organization MOm-Hellenic Society for the Study and Protection of the Monk Seal postulated that there had been considerable socioeconomic benefits for the local community of Alonissos due to the establishment of the NMPANS, whereas the local nongovernmental organization Ecological and Cultural Movement of Alonissos claimed benefits were scant. Tourists (domestic and foreign) believe that the NMPANS is not the main attraction to Alonissos Island but is part of a composite, including serenity, aesthetic beauty, and small-scale tourism development, which can turn Alonissos Island into an ideal eco-tourism destination; a common aspiration for both the tourists and the local community by general consensus. The aim of the NMPANS to integrate conservation and development lies in (1) the effectiveness of the NMPANS management body in formulating a strategic management plan that would accommodate stakeholders' interests and aspirations and (2) a national policy of conservation and enhancement of natural resources with consistency and continuity. Quantitative assessment of the socioeconomic effectiveness of the Mediterranean MPAs using a common methodology would facilitate the identification of intraregional variation and better planning for the network of MPAs in the Mediterranean.

Thessaly with Northern Sporades

Thessaly with Northern Sporades

DIVING DEVELOPMENT AND BEHAVIOR OF A REHABILITATED MEDITERRANEAN MONK SEAL (MONACHUS MONACHUS)

AbstractAmong the priority actions identified for saving the critically endangered Mediterranean monk seal are gaining basic biological information on movements and behavior, and rescuing and rehabilitating wounded, stranded, and orphaned pups. On 22 May 2004 a rehabilitated monk seal juvenile was fitted with a satellite tag, released in the National Marine Park of Alonnisos, Northern Sporades, Greece, and monitored for 167 d. Postrelease, the seal remained close to the islands of the park and within the 200‐m isobath. Throughout the monitoring period, the seal reduced time hauled out, while 95‐percentile dive duration and depth gradually increased. The overall maximum depth of 123 m recorded in this study is the greatest depth ever recorded for the species. These results confirm the effectiveness of the rehabilitation program carried out on the particular animal and provide additional support for the continuation of the rehabilitation program as a conservation measure for the species. We demonstrate that satellite tracking of rehabilitated seals is a valuable research and conservation tool, even for a species that commonly uses shoreline caves for resting, molting, and parturition.