Biodiversity of the Proposed IMMA of the Turkish Straits System

Liam van Walsum^1*, Enorha Guimard¹, Tim Awbery¹, Belen Yıldırım¹, Aylin Akkaya¹

¹DMAD – Marine Mammals Research Association, Antalya, Turkey

*corresponding author: rt.gr1734333957o.dam1734333957d@mai1734333957l1734333957

Keywords: Cetaceans; Conservation; Pressures; Istanbul; Sea of Marmara

The Turkish Straits System (TSS) is an important waterway that serves as a trade artery for a large part of Central and Eastern Europe, holds strategic importance as a gateway for world navies and is historically considered the divide between Europe and Asia. However, the system is also important as it hosts a diverse array of marine mammals and was recently proposed as an IMMA because of this diversity.

The system itself consists of the Istanbul Strait (Bosphorus), Sea of Marmara and the Canakkale Strait, and connects the Black Sea to the Mediterranean via the Aegean Sea. The Black and Aegean seas have a distinct salinity gradient and therefore the Sea of Marmara behaves as an acclimatisation water body for organisms travelling through the strait.

The TSS hosts two marine mammal assemblages: The Black Sea assemblage consisting of genetically distinct subspecies of Bottlenose dolphins (Tursiops truncatus ponticus), Short Beaked Common dolphins (Delphinus delphis ponticus), and Harbour porpoise (Phocoena phocoena relicta); and the Mediterranean assemblage of Bottlenose dolphins (Tursiops truncatus), Short Beaked Common dolphins (Delphinus delphis), and Mediterranean Monk seals (Monachus monachus). Species from both assemblages have been sighted within the Sea of Marmara but the extent to which species interact and mix has not been definitively determined.

The organisms that reside and travel within the TSS are subject to immense human pressures such as noise pollution, ship strikes, oil pollution, plastic pollution, entanglement, bycatch and light pollution. The extent to which these pressures impact these organisms is also not definitively known but may shed light on how cetaceans may adapt to human development.

The MECO project (Mediterranean Elasmobranch Citizen Observations): using social media to create a regional database of elasmobranch observations

Adi Barash^1,2*, Julia Türtscher³, Patrick L. Jambura³

¹Department of marine biology, University of Haifa, Israel

²Sharks in Israel, Environmental Organization for the protection of sharks and rays, Israel

³Department of Palaeontology, University of Vienna, Austria.

*corresponding author: moc.l1734333957iamto1734333957h@hsa1734333957rabid1734333957a1734333957

The alarming state of sharks and ray in the world and specifically in the Mediterranean Sea has been described again and again. In order to create effective management plans for species conservation of the species, we need basic ecological data as abundance, seasonality and population trends. Regional species composition is a crucial step in identifying important areas for their high diversity, keystone and endangered species. Within the elasmobranch group the gap between the risk assessments and the basic ecological knowledge is extremely vast.

Large scale datasets are being built all over the world for both terrestrial and marine species. Given the relative rarity of sharks and rays, methods that are used for scientific surveys or citizen science projects, do not succeed in their case. A more direct and intentional search method is needed for searching elasmobranchs records. Since the Mediterranean coast is divided into many nationalities and many languages, such effort will be best accomplished in small research groups, familiar with the language and local customs. The MECO project is also unique in the use of popular platforms, widely used by people around the world, thus requiring very little effort or commitment from the observers. Such commitment is usually very difficult to maintain through time.

The MECO project aims to bridge the knowledge gap, utilizing public knowledge and social media. Local scientists are searching the media, contacting the public and creating a large, verified database of elasmobranchs observations. The project began in 2014 as a Facebook group named “sharks in Israel” followed by the Greek NGO “iSea” which joined in two years later and establish its own Facebook group collecting data from Greece and Cyprus. Requesting observations from the public on an open media also exposes the public to scientific research, species variation and result in public education as an additional outcome of data collection.

Other groups around the Mediterranean have joined the MECO project from Turkey, Spain, France, Libya, Italy, Malta, Montenegro and Albania. Our groups have nearly 30,000 members who report, share information, ask questions and learn about shark and rays. All together we have so far collected over 6000 observations of 65 species of sharks and rays, from 19 countries.

In some regions we were able to describe Seasonal changes for the most observed species, distribution along the coast and differences in species composition and seasonality among regions. The data allows us to analyze the changes through time, and to pinpoint key locations and seasons for specific species.

The MECO project is based on collaboration and education and is planned as a long-term venture. We aspire that the data collected will contribute much needed information on the status of Mediterranean elasmobranchs and will be used to improve conservation efforts in this data deficient region.

A pristine Posidonia oceanica meadow in the Eastern Mediterranean: a refugium against warming
and deoxygenation?

Martina Holzknecht^1*, Paolo G. Albano^1,2

¹Department of Palaeontology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria

²Stazione Zoologica Anton Dohrn, Villa Comunale, Naples, Italy

*corresponding author: ten.x1734333957mg@th1734333957cenkz1734333957loh_a1734333957nitra1734333957m1734333957

Keywords: Seagrass; Mollusca; global warming; Lessepsian invasion; Crete

The seagrass Posidonia oceanica forms extensive meadows in the Mediterranean Sea. Studies on their associated highly diverse invertebrate assemblages are limited to the western Mediterranean. The Eastern Mediterranean, however, is a basin undergoing rapid change due to the synergistic effects of climate warming, biological invasions and other human stressors that are driving native biodiversity to regional scale collapses. We here surveyed the shelled molluscan assemblage of a Posidonia meadow in Plakias, south-western Crete, an area which has increased its yearly mean temperature by 1°C in the last 20 years and is under heavy pressure by Lessepsian species. We sampled across a 5 to 20 m depth gradient, in two seasons to capture intra-annual variation and the leaf and rhizome layers separately. Against our expectations, the molluscan assemblage proved to be highly diverse, with species richness, dominant species and trophic guilds comparable to healthy western Mediterranean ones, and with a negligible non-indigenous component. In warming waters, deoxygenation is an important effect contributing to reduced growth and survival. The photosynthetic activity of Posidonia meadows, however, causes an oxygen supersaturation that may counteract warming- induced deoxygenation enabling the persistence of diverse native communities in warming seas. Such diverse communities have greater resistance to biological invasions suggesting that Posidonia meadows may act as a precious refugium for native biodiversity in the fast changing eastern Mediterranean Sea.

Investigating an apparent decline of Bottlenose Dolphins in Montenegro & how Citizen Science has helped to fill data gaps during the current pandemic

Laura Rudd^1*, Tim Awbery¹, Selina Brouwer¹, Sian McGuinness¹, Enorha Guimard¹, Liam van Walsum¹, Aylin Akkaya¹

¹DMAD – Marine Mammals Research Association, Antalya, Turkey

*corresponding author; rt.gr1734333957o.dam1734333957d@ddu1734333957rarua1734333957l1734333957

Keywords: Adriatic Sea; Cetacean; Coronavirus; Conservation

A lack of baseline knowledge is one of the biggest barriers in the way of effective conservation and management of endangered species. Montenegro is the only country in the Adriatic Sea apart from Bosnia and Herzegovina (coastline = 20 km) with no marine protected areas. Land- and boat-based surveys began in September 2016 to increase knowledge about the distribution, behaviour and residency patterns of cetaceans in Montenegrin waters. Thus far, over 100 boat-based surveys and over 500 land-based have been conducted with a total of more than 2000 hours. Across this timeframe, there appears to have been a notable decrease in the percentage of surveys where bottlenose dolphins were sighted from 43% of surveys in the first twelve months (September 2016 – September 2017 to 22% in the fourth year (September 2019 – September 2020) of surveys. The study also investigated the anthropogenic activities that have the potential to negatively impact the bottlenose dolphins, in order to best inform future conservation decisions.

As aforementioned, restrictions due to the pandemic decreased survey efforts in Montenegro with no surveys taking place between the 10th of March and the 2nd of July 2020. A sighting network was set up to try and aid survey effort through citizen science. More than 20 sightings were reported, from the launch of the network on 1^st September 2020 until March 12^th 2021. Whilst this seems a relatively low number, only 22 sightings were made by our onsite researchers during this period and so citizen science played an important role in supplementing data in a year of limited surveying ability. Evidence of submitted sightings were often provided with photos, giving authors reason to believe that submitted information was generally accurate and could help supplement surveys during and after COVID-19 restrictions.

The experience of engaging citizens on projects about recording marine wildlife

Chris Taklis^1*

¹BiodiversityGR, Liri, Magnesia, Greece

*corresponding author: moc.l1734333957iamg@1734333957silka1734333957tc1734333957

Keywords: Citizen science; conservation; marine wildlife; citizen engangement

Enganment of citizens is not something new, even the biggest researchers in history were citizens without proper education of wildlife or biology. But in the last five decades things are changing rapidly in every direction, especially with the biodiversity loss.

Now, in 21st century, it’s more urgent to record as many species we can, before they extinct. To do that we need more hands and observers to work in the field but that is really expensive and there are not so many scientists to work every day and everywhere in the field.

The cheapest and most times better solution is, to be able to give proper education on simple enthousiast citizens of how to observe, record and even engange with marine wildlife. In that way they can give huge amount data, especially on coastal marine biodiversity but in the same time the biologists and researchers are giving support to the citizen-scientists and educate them.

That shows that it’s the best solution on recording marine wildlife constantly and having educated citizens that can even help you further on the future with your research.

“Citizen Science and how it can help in marine research”