The Bosphorus is a strategic waterway running through Turkey. This natural strait connects the Black Sea to the Sea of Marmara. At its southern end it weaves through Istanbul, cleaving the city into two parts, one part in Asia and one part in Europe. To an “Istanbullu” (a resident of Istanbul), it is a fisherman’s paradise. Nothing compares with the fish of the Bosphorus, he will say. He knows the best fish there and the best time to catch them.
To understand fishing in the Bosphorus, one needs to know a bit about the waterway. It is roughly 20 miles long and averages about 1 mile in width. Interestingly, there are two different currents in the Bosphorus. The surface current flows from north to south, carrying brackish water from the Black Sea to the Sea of Marmara and then to the Aegean. The under current flows in the opposite direction, from south to north, bringing more salty water from the Aegean to the Sea of Marmara, and ultimately to the Black Sea after passing through the Bosphorus.
The mechanisms responsible for two currents in the straight are as follows. The south-bound surface current of the waterway is the result of differences between the water levels of the Black Sea and the Sea of Marmara. The higher Black Sea receives fresh water from several rivers and this difference in water level activates the surface current. The north-bound lower current is due to differences in salinity between the Black Sea and the Sea of Marmara. Salty water coming from the Sea of Marmara is heavier than the brackish water of the Black Sea. It creates a permanent layer of salty water in the Black Sea that sinks to the bottom due to its density. The water below about 650 feet has no oxygen, and no marine life. It is essentially a dead sea at this level.
Now, to get back to the fish in the Bosphorus. There are both sedentary and migratory fish in the waterway. The sedentary species include the striped sea bream (“karagöz”), the brown meagre (“eskina”), and the gilthead sea bream (“çipura”). The migratory fish include the bluefish (“Pomatomus saltator”), the Atlantic bonito (“Sarda sarda”), Atlantic mackerel (“Scomber scombrus”), and horse mackerel (“Trachurus trachurus”). In the spring, these migratory fish swim north from the Aegean to the Sea of Marmara and then through the undercurrent of the Bosphorus to the Black Sea to spawn. When the water cools down in late summer, the fish return to home--the warmer Sea of Marmara and Mediterranean--passing through the Bosphorus in the upper current.
Of all the fish that remain in or pass through the Bosphorus, it is the migratory bluefish that is the most popular because it is deemed the most flavorful of all. Like several other fish, the bluefish has different Turkish names depending on its size. It is called “defne” when about 4 inches long; “çinekop” when a few inches longer; “lüfer” when about 10 inches long, and “kofana” when about 14 or more inches long. Note that the king of bluefish, the tastiest one according to the Turks, is the “lüfer,” and this is the favorite one ordered when dining out or purchased at a fish market. Fishing season occurs while bluefish migrate back home to the Sea of Marmara and Aegean, between September and late December. When bluefish migrate back to the plankton-rich Black Sea in May to spawn once again, the fish are not considered particularly tasty at this time so are not sought after by fishermen.
Bluefish. Credit: Wikipedia
Striped Sea Bream (“karagöz”). Credit: @pngguru
Brown Meagre ("Eskina"). Credit: https://www.mavimarinbalikcilik.com/eskina/