Marine turtles, have populated Earth for over 100 million years and they are considered as indicator species or sentinel species. This means that their abundance, distribution and health in the ecosystem are reflective of environmental conditions. It is therefore critical that they are protected and preserved. Although they have natural predators, the greatest threat to these ancient mariners are impacts and disturbances by human activities:
- Habitat loss and degradation of nesting beaches due to coastal and marine development and tourism.
- Pollution: marine litter ingestion (e.g. plastics), entanglement in ghost nets, oil spills.
- Collision with vessels: the Mediterranean sea hosts 1/6 of the global maritime traffic,whilst it only represents 0.8% of the ocean surface. Collision with vessels is thus one of the most common causes for sea turtle serious or fatal injuries.
- Fisheries: incidental captures of vulnerable species, like marine turtles, during fishing operations is one of the main threats for their abundance. Incidental captures constitute a problem for fishers too, as they reduce their catch and damage their gear.
- Exploitation: although trade and exploitation of marine turtles for meat, blood or artefacts is prohibited across the Mediterranean and beyond, illegal trade still takes place. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) lists the Loggerhead, Green and Leatherback turtles under Appendix I, meaning no trade is allowed, or trade is allowed only with permits under exceptional circumstances.
- Climate change: marine turtles have survived and adapted to climatic changes throughout the years. However, now that climate change is occurring at an alarming rate (i.e. rising of the global temperature, rising of sea level, acidification of the oceans, etc.), it is unknown how marine turtles will adapt, especially as they face extra pressures from human activities (i.e. habitat loss and degradation, pollution, collision with vessels, bycatch, etc).
* The above list by no means exhausts all threats that marine turtles encounter. It’s only an indicative list of some of the most important threats.