**Abstract**

The Syrian marine water is one of the least studied areas for cetaceans in the Mediterranean Sea. Lack of basic knowledge, such as species composition and habitat, makes it impossible to develop effective conservation measures. The survey carried out along the Syrian coast by monitoring the stranding individuals on the shore since 2002 showed that there were 11 species of marine mammals living in/or visiting the Syrian marine waters at present of which 10 species belonging to the cetacean order and on belonging to pinnipeds order. The following species have been recorded: *Pseudorca crassidens*, *Megaptera novaeangliae*, *Physeter macrocephalus*,*Tursiops truncatus*, *Stenella coeruleoalba*, *Delphinus delphis*, *Ziphius cavirostris*, *Grampus griseus*, *Balaenoptera physalus*, *Balaenoptera acutorostrata*, and *Manchus manchus*. On the other hand, there are four species whose presence in the Syrian marine waters was mentioned a century ago by the researcher Gruvel and his team during three missions (1929–1931), but neither alive nor dead have been seen in this area during the surveys that were carried out since 1996 until the present, these species are: *Phocoena phocoena*, *Globicephalus melas*, *Phocoena communis*, *Hyperoodon rostratus*, *Balaenoptera musculus*. These observations reflect the vulnerability of marine mammals to anthropogenic activities, such as fishing operations, shipping, seismic activities, and climate change.

**Keywords:** marine mammals, cetaceans, stranding, climatic changes, Mediterranean Sea, Syria

### **1. Introduction**

Although the Mediterranean constitutes only less than 1% of the total area of the world's oceans and seas, it contains 18% of the world's marine biodiversity and contains 28 species of marine mammals (resident, visiting, or roving) that have occurred in the Mediterranean. The species that studies and surveys have proven to be endemic to the Mediterranean are: 11 species of cetaceans: fin whale (*Balaenoptera physalus*); sperm whale (*Physeter macrocephalus*); Cuvier's beaked whale (*Ziphius cavirostris*); short-beaked common dolphin (*Delphinus delphis*); long-finned pilot whale (*Globicephala melas*); Risso's dolphin (*Grampus griseus*); killer whale (*Orcinus orca*); striped dolphin (*Stenella coeruleoalba*) rough-toothed dolphin (*Steno bredanensis*); common bottlenose dolphin (*Tursiops truncatus*); harbor porpoise (*Phocoena phocoena relicta*) and the Mediterranean monk seal (*Monachus monachus*) have adapted well to the region's environmental conditions, but their coexistence with humans is problematic. All the regular species are represented in the Mediterranean by populations genetically distinct from their North Atlantic relatives. Seventeen

other species (3 fins and 14 cetaceans) are considered non-endemic, but rather visitors to the Mediterranean heat coming from adjacent regions for various reasons [1]. The Mediterranean is experiencing severe changes as a result of high levels of human activity pressure and its synergistic interaction with the effects of climate change which has affected marine biodiversity [2].

Interactions between marine mammals and commercial fisheries have occurred for centuries and the interactions do not seem to decline. Bycatch, i.e., the unwanted or incidental catch of species other than the target species, is a severe problem in conservation biology and a potential threat to the future survival of marine mammal populations. Marine mammal's populations decline is considered to be an important issue in terms of the biodiversity of vulnerable species and numerous cases of stranding have been documented in the Mediterranean Sea were particularly in the eastern part of the basin [3].

This chapter includes: (1) A review of the available information and data about marine mammals in Syria a century ago; (2) Presentation of the results of the continuous monitoring that we started implementing in 2002 on the stranding of individuals of marine mammals on the Syrian coast; (3) Results of a field survey study at sea onboard research ships Yunis S for a week during August 2008 in partnership with a team from the Faculty of Fisheries at Istanbul University, within the framework of a joint Syrian-Turkish-Lebanese research program; (4) Results of a field survey study at sea that was carried out onboard an Okeanos boat during the month of September 2019; (5) Presentation of the threats that threaten marine mammals in Syria; (6) Presentation of laws and regulations related to the protection of marine mammals in Syria.

#### **Figure 1.**

*Map of the Syrian coast on which the most important cities and ports are located, near which the strandings of cetaceans and seals have been recorded during the last 20 years.*

We have included below the map of the Syrian coast (**Figure 1**) to clarify the approximate geographical locations that are mentioned when talking about the stranding sites of cetaceans and monk seals on the Syrian coast.
