Ak koyun (White Sheep) is the name of a tribe. From the Wikipedia: The Ak Koyunlu or Aq Qoyunlu, also called the White Sheep Turkomans (Turkmen: Akgoýunly, Azeri: Ağqoyunlu, Turkish: Akkoyunlu, Ottoman Turkish/Persian: آق قوینلو), was an Oghuz Turkic tribal federation, that ruled parts of present-day Eastern Turkey, Armenia, Azerbaijan, northern Iraq, and western Iran from 1378 to 1508. I am not quite certain that that is the reason of existence for this representation of a sheep in a park, but it’s a nice thought.