It is a satellite lake of Lake Kyoga, which it drains into, and the two are to some extent directly connected by papyrus swamps.

[3] During the high-water rainy season, Lake Bisina can be up to 6 m (20 ft) deep and often directly connects with the smaller Lake Opeta, but during the dry season the two are clearly separated.

[4] The lake is important for fish, notably several threatened haplochromine cichlids like Haplochromis orthostoma,[5] H. argenteus (appears to have disappeared from its main range in Lake Victoria), H. latifasciatus, H. lividus, H. martini (appears to have disappeared from its main range in Lake Victoria), H. maxillaris, H. nubilus, H. parvidens, H. phytophagus and a number of undescribed species.

[6] Although Nile perch was introduced to Lake Bisina in the early 1970s, recent surveys have not detected this species, which has been implicated in the extinctions of many haplochromine cichlids elsewhere.

[1][6] Other, more widespread fish species found in Lake Bisina include marbled lungfish, and various species of catfish, African tetras and elephantfish.