Attracting Common Carp to a bait site with food reveals strong positive relationships between fish density, feeding activity, environmental DNA, and sex pheromone release that could be used in invasive fish management

Abstract

Voluntary Ingestion of Soft Plastic Fishing Lures Affects Brook Trout Growth in the Laboratory

Abstract

Thirty‐eight brook trout Salvelinus fontinalis were fed a commercial trout diet mixed with a free‐choice assortment of soft plastic lures (SPLs) over a 90‐d period. Fish growth was recorded and compared with that of a control group. The brook trout readily ate the SPLs from the water's surface as well as from the tank bottom. At the conclusion of the study, SPLs were recovered from the stomachs of 63% of the test fish. Several fish stomachs contained multiple lures. Twelve percent of the fish voluntarily ingested more than 10% of their body mass in SPLs. These fish lost a significant amount of weight during the study, had a significant decrease in body condition factor, and began displaying anorexic behaviors. For these reasons, anglers should be discouraged from discarding used SPLs in trout waters.

Effects of Ingestion of Soft Plastic Fishing Lures on Largemouth Bass

Abstract

Soft plastic lures (SPLs) may comprise a significant amount of fishing gear pollution, yet little is known about their environmental impacts in aquatic systems or their ingestion by fish. We tested whether shape and material composition of ingested SPLs influenced subsequent prey consumption by Largemouth Bass Micropterus salmoides after SPL ingestion. We also quantified the occurrence of SPL ingestion by Largemouth Bass in reservoirs. Biodegradable and nonbiodegradable versions of shad, ribbon‐tail worm, and finesse worm SPLs were fed to Largemouth Bass, and consumption of natural prey was quantified 1 d and 1 week postingestion. Shape and material composition altered prey consumption by Largemouth Bass. Fish that ingested the shad SPL, the largest lure by volume, consumed the fewest number of prey 1 d postingestion. Ingestion of biodegradable SPLs resulted in lower prey consumption rates than ingestion of nonbiodegradable SPLs. Largemouth Bass typically expelled the SPL within 9 d of ingestion; all lures were either regurgitated or egested. Less than 1% of Largemouth Bass sampled in two Illinois reservoirs had SPLs in their stomachs. Our results suggest that discarded SPLs do not pose a significant long‐term threat to the health of individual Largemouth Bass. However, SPLs should still be discarded in a responsible manner.