Birds are caught using Japanese mist nets, which are widely used in international ringing studies, and ringers identify their age, sex and other features. (AA Photo)
Birds migrating between Europe and Africa use Istanbul to rest and feed before continuing their long journeys, with ringing studies at Istanbul University-Cerrahpaşa’s Avcılar Campus helping scientists track their movements and habitats.
Istanbul is one of the world’s most important migration routes, particularly for birds that migrate by soaring. Much of the activity, however, goes unnoticed because many birds cross the city at night.
During their journeys between Africa and Europe, birds use Istanbul’s natural areas to replenish their energy. Green spaces with natural vegetation, including blackberries, figs and other fruits, provide important feeding areas where birds can regain strength before continuing their migration.
Ringing studies record not only a bird’s species but also individual characteristics. If a ringed bird is later found or captured in another country, the ring provides information about where and when it was previously recorded.
This allows researchers to trace migration routes and gather information about where birds feed, breed and stop during their journeys, as well as their life spans.
At Istanbul University-Cerrahpaşa’s Avcılar Campus, birds are caught using Japanese mist nets, which are widely used in international ringing studies. The nets are generally placed near feeding areas and bushes, and birds are carefully removed during regular checks.
Experienced ringers licensed by the Nature Conservation and National Parks (DKMP) department of the Ministry of Agriculture and Forestry identify the birds and record their age, sex when possible, fat and muscle condition, wing and tail lengths and weight. Parasites can also be examined.
After being ringed, the birds are released back into the wild. When they are later spotted in another country, researchers can track their movements between locations.
A spotted flycatcher ringed in Romania, a reed warbler ringed in Slovenia and a blackcap ringed in Israel are among birds later recorded in Istanbul. A blackbird ringed in Istanbul was subsequently recaptured at another ringing station in Ukraine.
Such records allow ringing stations in different countries to share data and help researchers build a broader picture of bird migration.
From Istanbul to Africa
A significant proportion of birds ringed at the Avcılar Campus head toward Africa in autumn. Some travel as far as sub-Saharan Africa, South Africa, Tanzania and Kenya, while others winter along the Mediterranean coast or in southern Türkiye. Some species travel as far as India.
Ergün Bacak, head of the Hunting and Wildlife Program at Istanbul University-Cerrahpaşa’s Vocational School of Forestry, said ringing studies allow researchers to identify individual birds and monitor their movements.
“Just like our identification numbers, we give birds an identity. This allows us to distinguish each individual and study their behavior, life spans, breeding success, valuable habitats and, particularly, their migration routes,” Bacak said.
He described Istanbul as an important stopover for migratory birds.
“Istanbul is an important fueling station and a resting station. It is a very important area for birds to rest and feed during their migrations from Africa to Europe and from Europe to Africa,” he said.
Bacak stressed the importance of protecting green areas with natural vegetation.
“Areas with blackberries, fruits and figs and natural vegetation are very important fueling areas for birds. Such areas need to be left with their natural habitats and vegetation,” he said.
Bacak said this year’s studies began on Aug. 10 and nearly 1,000 birds had been ringed so far, although the figure was still changing as the work continued.
He said around 2,000 to 2,500 birds are normally ringed in spring and 2,500 to 3,000 in autumn. More than 7,000 birds were ringed during the autumn season last year due to wetter weather conditions.
“We estimate that we will ring between 2,500 and 3,000 birds this season,” Bacak said.
He said many of the ringed birds would migrate to Africa, with some traveling as far as South Africa, Tanzania and Kenya, while others would winter in the Mediterranean, southern Türkiye or India.
The migration distance varies by species. A spotted flycatcher weighing around 10 grams can travel to India, while nightingales and thrush nightingales weighing 20 to 30 grams can reach Tanzania and Kenya.
Bacak said this year’s dry conditions had affected migration.
“This year has been somewhat dry, and autumn is also dry. Therefore, we are seeing slightly lower numbers. It is a relatively unproductive period in terms of migration,” he said.
He added that ringing studies also help researchers monitor the effects of global climate change on birds and the environment, as migration dates, routes, migration choices and parasites can change.
Bacak also emphasized the educational value of ringing stations, particularly for children.
“When a child touches a bird and releases it back into nature, that child becomes a conservationist for life,” he said.
He said Istanbul’s natural areas should be protected despite the city’s large population.
“As we grow, we need to leave some locations in their natural state. This does not only mean protecting nature; it means protecting our children and protecting the future,” Bacak said.
He added that ringing studies also provide data for ecological monitoring, noting that international research can help identify parasites and diseases carried by birds and support measures to protect public health.
