[4] Other birds include a small colony of little egrets (Egretta garzetta) and the rare half-collared flycatcher (Ficedula albicollis semitorquata).

[1] Twenty-five fish species have been recorded in the river, seven of which are listed under the IUCN Redlist, including wild common carp, (Cyprinus carpio), Knipowitschia caucasica and the Aral stickleback, (Pungitius platygaster).

Mammals in the biosphere reserve include roe deer (Capreolus capreolus), wild boar (Sus scrofa), pine marten (Martes martes) and fox (Vulpes vulpes)[1] There are also many reptiles and amphibians, including the European pond turtle (Emys orbicularis), tessellated water snake (Natrix tessellata) and alligator lizard (Ophisaurus apodus).

The forests are dominated by ash (Fraxinus oxyphylla), Ulmus, oak (Quercus pedunculiflora), Acer and Alnus, with scrub of Crataegus monogyna, Cornus, Paliurus and Ligustrum, and lianas of Clematis, Smilax and Periploca.

Additionally, litter and industrial pollutants are regularly washed up on the shore, much of which either come from the port of Varna or the nearby Resort of Kamchia, (which shares the same beach line).

The comparison of data from different periods of investigation reveals a slight tendency of decreasing of phosphate and nitrites content and BOD.

A decreasing tendency was established as a positive sign of water quality evolution last yearsOther environmental issues are that the river is purportedly becoming marshy.