[2] Common roach, perch, crucian carp, pike, burbot, minnow, are among the native fish species in the lake.

[3] The 972 square kilometres (375 sq mi) catchment area of the lake is located in a forest steppe zone.

Bolshoy Yeravna has a roughly round shape and is fed by three small rivers, the Tuldun, Indola and Zhipkesen.

In the southwestern side it has an outlet, a small sound connecting with neighboring Lake Sosnovo.

There is also a dense growth of submerged benthic macrophytes, such as Potamogeton, Myriophyllum, Ceratophyllum, as well as algae (Chara) and water moss.