From 1881 to 1896, the state Fish Commission stocked about 100,000 common carp in 67 Wisconsin counties, and although other states also introduced carp, the fish thrived in the slow, shallow, weedy lakes of Dane County. Introduced to provide food for an expanding American population and encouraged by European immigrants accustomed to fishing for and eating common carp, they soon became so abundant that sport fishers complained the bottom-feeding carp damaged underwater vegetation and reduced water clarity, harming sport fishing. Within a few years, carp thrived at the expense of native sport fish such as musky, walleye, bass, and northern pike, and they also reduced waterfowl habitat, leading anglers to demand state action. For 30 years, Fish Camp worked to help stop the spread of carp. Contract fishing for carp continues in lakes such as Koshkonong near Fort Atkinson, while healthier lakes with less runoff help native fish outcompete carp. When Madison stopped dumping its sewage upstream of Lake Waubesa in the 1950s, carp populations in Waubesa and Kegonsa dropped.