The fish population of Lake Josephine is dominated by small bluegill and crappie, with very few quality sized panfish sampled in 2012. Northern pike are common, but of average size. No pike larger than 30" were sampled. Largemouth bass were sampled in average abundance, but small size. Only one largemouth larger than 16" was sampled. The walleye catch was average for this lake type, but the 2012 catch rate was the highest for this lake since recent walleye management was initiated in 1997. The average size of the walleye harvested was 19" long and weighed 2.5 lbs. Yellow bullhead were abundant, and of average size. Yellow perch, white sucker, carp and other sunfish species were sampled in low numbers.
- Eurasian Watermilfoil
Recreational activities such as recreational boating, angling, waterfowl hunting, and diving may spread aquatic invasive species. Some aquatic invasive species can attach to boats, while others can become tangled on propellers, anchor lines, or boat trailers. Many species can survive in bilge water, ballast tanks, and motors or may hide in dirt or sand that clings to nets, buckets, anchors, and waders. Fortunately, completing simple steps can prevent the transport of aquatic invasive species.