Entanglement in fishing nets and drowning is the most likely cause of death for over 300 birds of the protected Yelkouan Shearwater species and 9 dolphins found dead along the Northern Black Sea coast late last week. This is according to initial expert analyses.
“The birds’ bodies show clear marks from nets, and the flattened plumage indicates they had been submerged in the sea for some time,” commented ornithologist Ivaylo Ivanov from the Public Center for Environment and Sustainable Development (PECSD).
This version is also supported by Green Balkans, who pointed to the severed tails of two of the dolphins as further evidence. Recent gale-force winds quickly washed the birds ashore before they could be scavenged or decomposed. Due to strong currents, it is suspected that the nets were located in Romanian territorial waters. Some specimens found on the beach in the village of Ezerets may have perished near Durankulak, Ivanov suggested.
To prevent such incidents, pingers (acoustic deterrents) should be attached to fishing nets to keep dolphins and birds away. However, specialists admit this is rarely done due to weak enforcement.
Another theory involves ongoing trawling in the Black Sea, where birds may have been scooped up by trawls while feeding. The Yelkouan Shearwater feeds on fish, crustaceans, and mollusks, diving up to 45 meters in search of prey. It primarily comes ashore at night to nest and feed its young.
The initial version of bird flu was rejected still on Friday. The Black Sea Basin Directorate (BSBD) – Varna and the Regional Inspectorate of Environment and Water (RIEW) – Varna conducted a follow-up inspection along the Shabla coast. The BSBD has ordered water quality tests in the Shabla Lake area, with results expected in the coming days.
The Mediterranean petrel is a globally threatened species, with the status of “Vulnerable”. It nests colonially in rock crevices and holes. It lays one egg and has one generation per year in April-September.
There are no confirmed nesting sites in Bulgaria, but the species is found along the entire Black Sea coast. In the Mediterranean Sea and adjacent seas it is permanent and migratory. Birds from the Mediterranean population enter the Black Sea through the Bosphorus, mainly in spring and summer.
The primary threats to the survival of the Yelkouan Shearwater are overfishing, entanglement in fishing nets, hooking on baited lines, as well as oil spills.
