Biomass-dependent effects of common carp on water quality in shallow ponds

Abstract

We examined the biomass-dependent effects of common carp (Cyprinus carpio) on water quality in 10 ponds at the Eagle Mountain Fish Hatchery, Fort Worth, Texas, USA. Ponds contained 0-465 kg ha )1 of common carp. We measured limnological variables at weekly intervals for four weeks in early summer, after which ponds were drained and the biomass of fish and macrophytes was determined. Common carp biomass was significantly positively correlated with chlorophyll a, total phosphorus, total nitrogen, and Keratella spp. density and negatively correlated to bushy pondweed (Najas guadalupensis) biomass. In addition, we combined our data with data from comparable studies to develop more robust regression models that predict the biomass-dependent effects of common carp on water quality variables across a wide range of systems.

Bed disturbance via foraging fish increases bedload transport during subsequent high flows and is controlled by fish size and species

“…Specifically, Carp Cyprinus carpio have been found to resuspend fine sediment when foraging for food (Breukelaar et al, 1994;Parkos et al, 2003;Chumchal et al, 2005;Miller and Crowl, 2006;Roozen et al, 2007;Matsuzaki et al, 2009)…”

Moderate biomanipulation for eutrophication control in reservoirs using fish captured in angling competitions

“…Goldfish was the species with lower contents of TP and TN whereas the bleak 22 had the highest values of these nutrients. 23 According to the balance of inputs and outputs of TP and TN from angling competitions for 24 the biomanipulation scenarios studied, it was possible to determine that the inputs from the (scenario B3) were higher than the inputs from groundbaiting. For Groundbait (+), the inputs of TP equated the outputs only when it was used 1.5 kg of groundbait per angler and all Groundbait (−), and for TN the inputs from Groundbait (+) were nearly three times higher than 9 the inputs from Groundbait (−).…”

“…was performed. 22 This method is based on the complete oxidation of the sample converting all organic sub- 23 stances into combustion gases that pass through a reduction furnace (quartz tube furnace 24 at about 1030 • C) and are swept into the chromatographic column, where they are sepa-25 rated and detected quantitatively. In the process, excess oxygen is removed by contact with 26 copper, and nitrogen oxides are reduced to elemental nitrogen.…”

“…However, it would be positive to intervene in the ecosystem in order 24 to maintain well-structured fish populations, and to improve water quality in an expeditious 25 and inexpensive way. 26 Recreational angling is a popular leisure activity in Portugal with nearly 200 000 anglers li-27 censed for inland waters, as reported by the Institute for the Conservation of Nature and 28 Forests (ICNF), the state agency managing inland fisheries.…”

“…As a con-20 tainment measure, and to limit groundbaiting, Portuguese water managers have implemented 21 the obligation of an authorization to groundbait in angling competitions and the Portuguese 22 Angling Federation also decreased the quantities of groundbait that can be used in their 23 competitions. 24 Most of all, anglers should be informed of the water quality problems that may arise from the 25 practice of catch-and-release angling and groundbaiting. Anglers must be advised to be more 26 selective in the release of fish captured back to the reservoir and to use smaller quantities of 27 groundbaits as well as choose commercial groundbaits with low eutrophication potential.…”