Manyas Bird Lake

Manyas Bird Lake is located within the boundaries of Balıkesir Province in Türkiye’s Marmara Region, between the districts of Bandırma, Manyas, and Gönen. It lies approximately 14 kilometers south of the Sea of Marmara and 7.5 kilometers south of Bandırma Airport. The lake’s average surface area is about 16,400 hectares, with a maximum extent of 21,821 hectares. Its average elevation above sea level ranges between 15 and 60 meters. Manyas Lake is a shallow, expansive freshwater lake with an average depth of 2–3 meters and a maximum depth of 5.15 meters. The water remains consistently turbid due to the presence of colloidal clay.

The lake is fed surface-wise by the Kocaçay (Manyas Creek) from the south, the Mürvetler Stream from the east, and the Sığırcı and Dutlu Streams from the north, as well as by groundwater and precipitation. Rivers flowing into the lake form deltas that contribute to the coastal ecosystem. The lake’s outflow occurs through Karadere in the southeast. A regulator and environmental dams constructed on Karadere in 1992 artificially influence the lake’s water regime. The highest water levels are reached in spring (March–April), while the lowest occur in autumn (September–October). The lowest recorded water level was 14.4 meters in 1983, and the highest was 17.8 meters in 1996.

Hydrogeological and Geological Structure

Manyas Lake is a depression lake formed during the post-Miocene period. The area surrounding the lake is covered by alluvial deposits, and its clay-rich substrate reduces permeability. This characteristic directly affects the water balance in the lake’s vicinity. The stratigraphic sequence includes units ranging from Precambrian to Quaternary. Permian-aged carbonate and clastic rocks are common around the lake.

Climate Characteristics

The Manyas Basin exhibits transitional climate conditions between Mediterranean and continental climates. Winters are mild and wet, while summers are dry and hot. The average annual temperature is 14–15 °C, with an average humidity of 66–75 percent. The lowest recorded temperature is -14 °C (January), and the highest is 41 °C (July–August). Annual evaporation averages 1143 mm³. Precipitation is concentrated primarily between October and April.

Biodiversity

Bird Fauna

Manyas Bird Lake and its surroundings are protected by the Bird Paradise National Park, established in 1959 around the 64-hectare Sığırcı Delta, first discovered in 1938. In 2005, the park’s boundaries were expanded to include the lake, increasing its total area to 24,047 hectares.

To date, 266 bird species have been recorded in the area. Of these, 66 species breed regularly every year, 22 breed intermittently in certain years, and the remaining 178 species pass through during migration. Species such as the Dalmatian pelican (Pelecanus crispus), pygmy cormorant (Phalacrocorax pygmeus), black-crowned night heron (Nycticorax nycticorax), spoonbill (Platalea leucorodia), and glossy ibis (Plegadis falcinellus) form breeding colonies. During migration, the white pelican (Pelecanus onocrotalus) and during winter, the white-headed duck (Oxyura leucocephala) use the lake as a stopover. The park lies along internationally significant bird migration routes.

Other Fauna and Flora

Manyas Lake hosts 4.39 percent of Türkiye’s zooplankton fauna. A total of 29 zooplankton species have been identified, including 17 Rotifera, 9 Cladocera, and 3 Copepoda. Some of these represent the first recorded occurrences in Manyas Lake. The zooplankton composition is 45 percent Rotifera, 33 percent Cladocera, and 21 percent Copepoda.

118 plant species have been recorded around the lake. Dominant species include reed (Phragmites australis), willow (Salix sp.), ash (Fraxinus sp.), bulrush, reedmace, five-finger grass, and wild jasmine. Twenty-three fish species have been identified, including carp, tench, bream, and freshwater mullet, which have commercial value. Additionally, four species of salamander, six species of frog, four species of snake, two species of lizard, and two species of turtle have been recorded.

Protection Status and Management

• 1959: Bird Paradise was first declared a National Park.
• 1976: Awarded the “Class A European Diploma” by the Council of Europe. This diploma was periodically renewed in 1981, 1986, 1991, 1996, and 2004.
• 1994: Designated under the Ramsar Convention.
• 1981: The area was declared a First-Degree Natural Site.
• 2001: The Manyas Lake Management Plan came into effect.

Environmental Threats

The lake faces threats from various pollution sources. Major issues include:

• Industrial waste discharged via the Sığırcı Stream (e.g., from Etibank Borax Factory and olive, dairy, and oil processing facilities),
• Runoff of agricultural fertilizers and pesticides into the lake,
• Liquid manure from poultry farms reaching the lake via streams,
• Disruption of the lake’s ecological balance due to regulators and dams altering the water regime.

These threats lead to the loss of breeding habitats, degradation of water quality, and decline in biodiversity.

Economic and Socioeconomic Use

Agriculture (rice, maize, wheat, sunflower, sugar beet), livestock farming (large and small ruminants), and fisheries are the primary livelihood sources around the lake. Modern poultry farms are concentrated in the lake’s vicinity. Agro-industrial facilities are located around Bandırma.

Recreational use is dominated by birdwatching. Bird Paradise is one of Türkiye’s most renowned nature tourism destinations. An environmental valuation study estimated the lake’s annual total economic value at approximately 14.8 million Turkish Lira.

Access and Visitation

Bird Paradise National Park is accessible via a 3-kilometer road branching south from the 15th kilometer of the Balıkesir–Bandırma highway. Facilities include a visitor center, museum, birdwatching tower, and camera systems. The optimal visiting periods are March–July and September–October. Although there are no accommodation facilities within the park, lodging is available in nearby villages and in the district of Bandırma.

Historical and Archaeological Value

The ancient city of Daskyleion, located in the southeast of the lake, dates back to the Lydian period (7th century BCE). During the Persian era, it was used as a “Paradeisos” (royal hunting ground). The lake is mentioned in Evliya Çelebi’s Seyahatname.