If You Build It, Will They Come? Fish and Angler Use at a Freshwater Artificial Reef

Abstract

In November 1999, an artificial reef composed of granite rubble was built in southwestern Lake Michigan to attract smallmouth bass Micropterus dolomieu. Adult fish communities were sampled at the artificial reef site and a nearby reference site before (1999) and after reef construction (2000–2003) to determine whether the artificial reef attracted sport fishes. The total number of fish observed along scuba transects was higher at the artificial reef than at the reference site during 2000–2003. Smallmouth bass, rock bass Ambloplites rupestris, round goby Neogobius melanostomus, and yellow perch Perca flavescens were most commonly observed by divers at the artificial reef site, whereas the round goby was the most prevalent species observed at the reference site. Mean annual total gill-net catch per unit effort (CPUE) did not differ at the two sites after reef construction. Freshwater drum Aplodinotus grunniens, gizzard shad Dorosoma cepedianum, yellow perch, and salmonines were commonly caught at both locations. The presence of several of these taxa was related to water temperature but not location. Smallmouth bass presence was related to location; CPUE was greater at the artificial reef than at the reference site during 2000–2002. Rock bass CPUE also was greater at the artificial reef than at the reference site during 2002. Smallmouth bass association with the reef was seasonal and correlated with temperature. Although anglers were aware of the artificial reef, fishing effort and success were low, in part because few anglers targeted black bass Micropterus spp. Because water temperature strongly influences the use of structure by centrarchids in deep, cold lakes like Lake Michigan, care must be taken to site artificial reefs in zones of the most suitable water temperature for these species.