Beyobasi Yuvarlak Cay Tours
With the aim of identifying the fish fauna of Yuvarlakçay Stream, is an important stream located in the Köyceiz Lake basin, a number of fish samples were collected and evaluated from five different stations on Yuvarlakçay Stream. Consequently, 13 taxa were determined belonging to 9 family.

These are  Anguilla anguilla, Leuciscus cephalus, Barbus plebejus escherichi, Capoeta capoeta angorae, Leuciscus borysthenicus, Ladigesocypris ghigii ghigii, Cobitis vardarensis  kurui, Gambusia affinis, Mugil cephalus, Atherina  boyeri, Tilapia zillii, Blennius fluviatilis  and Knipowithschia caucasica. of them, Leuciscus borysthenicus  is the new record for Yuvarlakçay Stream. Furthermore, Mugil cephalus, Atherina boyeri and Knipowithschia caucasica were determined in station 5, although they were notified before in Köyceiz Lake.