Evaluation of artificial PVC pipe structures as fish habitat in Spring Lake, Western Illinois, USA

Abstract

Three types of artificial fish habitat constructed of polyvinyl chloride (PVC) pipe were placed at three sites in Spring Lake, a drinking water reservoir in McDonough County, Illinois. Direct current (DC) electrofishing was used on a monthly basis from May through October 2008 at each site, and a corresponding control area. The fish catch per unit effort (CPUE) and mean size of fish captured were compared between the artificial structures and the control areas. The CPUE and mean size of fish captured also were compared to the number of ‘branches’ on the artificial habitat. The fish catch rates for the various structures were evaluated among the three sites on the lake. The mean CPUE was significantly higher for the PVC structures, and compared to control sites, for bluegill (Lepomis macrochirus), white crappie (Pomoxis annularis) and largemouth bass (Micropterus salmoides). This was not performed for gizzard shad (Dorosoma cepedianum). No significant differences were detected in mean size for all four species between the PVC and control sites. A linear regression indicated no significant relationship between the number or size of fish, and the number of branches on the PVC structures. Bluegills used the PVC structures significantly more in the dam area than in other areas of the lake. In contrast, gizzard shad used the PVC structures significantly more in the west end of the lake. These results suggest that PVC structures, which can be constructed of common, inexpensive materials, can be effective in attracting fish in drinking water reservoirs. Another advantage of the PVC structures is that they are non-organic and, therefore, will not degrade water quality.