Lake Sturgeon (Acipenser fulvescens), FMNH no. 98256. Field Museum of Natural History, Chicago. Conservation status: least concern. However, the state of Michigan lists the species as threatened. Populations have declined in the last century due to overfishing, pollution and damming has destroyed spawning runs. Slow growth and slow sexual maturation make this sturgeon particularly vulnerable. Lake sturgeon have been fished for their flesh and their oil as well as for their caviar. Steamboats on North American rivers once used their oil as fuel.