In the last century, this large fish was often regarded as a nuisance because it often became entangled in and caused commercial fishing nets to become ripped. Only much later did the sturgeon become prized for its meat, eggs (caviar) and oil. Gelatin from the inner lining of its air bladder was used to make isinglass--a substance used as a clarifying agent in jellies, glues and in the isinglass windows of carriages and early cars. Nowadays, the lake sturgeon's dark form can be sometimes be discerned in reedy shallows or near river mouths.