Bosphorus (741)
Turkey, Europe
Site overview
KBA status: confirmed
Global KBA criteria: A1b, A1d, B1, D1a
Year of last assessment: 2016
National site name: Boğaziçi
Central coordinates: Latitude: 41.2667, Longitude: 29.2000
Elevation (m): 0 to 400
Area of KBA (km2): 553.16671
KBA classification: Global
Legacy site: Yes
Site details
Site description: The Boðaziçi strait runs north-south for c.33 km, and is c.1.5 km wide. The site includes the forested areas east (Polonezköy Nature Park) and west (Belgrade forest) of the strait, which are known to be of importance to roosting migrants. It does not include the çamlýca hills and the islands in the Sea of Marmara, which would qualify as an IBA in their own right due to the large numbers of migrants passing over, but which provide limited scope for bird conservation.
Rationale for qualifying as KBA: This site qualifies as a Key Biodiversity Area of international significance that meets the thresholds for at least one criterion described in the Global Standard for the Identification of KBAs. KBA identified in the CEPF Ecosystem Profile of the Mediterranean Hotspot (2017). Taxonomy, nomenclature and global threat category follow the 2016 IUCN Red List.
Additional biodiversity: The site is a major migratory bottleneck, where more than 20,000 storks and raptors regularly pass in spring and autumn. Few counts covering the entire migration period have been undertaken. Total counts made in the mid-1960s and early 1970s and covering the entire autumn migration period are as follows: Ciconia nigra (8,318), Ciconia ciconia (338,353), Pernis apivorus (25,751), Milvus migrans (2,707), Buteo buteo (32,895) and Aquila pomarina (18,898). More recent autumn records include 11,703 Aquila pomarina at çamlýca and 11,379 of the same species at Sarýyer, both on the same day in September 1990. Ciconia sp. often roost in flocks of thousands in fields outside the city. Disturbance by Larus cachinnans and possibly pollution are thought to be behind a drastic decline in numbers of breeding Milvus migrans.
Habitats
Land use: agriculture (15%) | fisheries/aquaculture | forestry (50%) | military (5%) | tourism/recreation (5%) | urban/industrial/transport (15%)
| IUCN Habitat | Coverage % | Habitat detail |
|---|---|---|
| Artificial - Terrestrial | 29 | |
| Forest | 59 | |
| Marine Neritic | 10 | |
| Wetlands(Inland) | 1 | |
| Marine Coastal/Supratidal | 1 |
Threats
Summary of threats to biodiversity at KBA: The main threat is the rapid urban and industrial expansion of Ýstanbul. Mining and road building also result in the loss of natural habitats. The conservation of forested areas on both sides of the strait is crucial, in order to preserve raptor roosting sites. There are isolated instances of raptor persecution.
| Threat level 1 | Threat level 2 | Threat level 3 | Timing |
|---|---|---|---|
| Residential & commercial development | Housing & urban areas | Ongoing | |
| Transportation & service corridors | Roads & railroads | Ongoing | |
| Transportation & service corridors | Flight paths | Ongoing |