780 BioScience • September 2005 / Vol. 55 No. 9 M ecologists and evolutionary biologists are familiar with the saga of the introduced Nile perch (Lates niloticus) in Lake Victoria. The explosion of the lake’s Nile perch population in the 1980s was monitored closely, because it coincided both with a fivefold increase in the economic value of the fishery (Reynolds et al. 1995) and with a halving ...

The exotic zebra mussel, Dreissena polymorpha, is established in all of the Laurentian Great Lakes and may affect benthivorous fishes by increasing the complexity of benthic substrates and changing energy flow patterns within the food web. Native yellow perch, Perca flavescens, and the nonindigenous Eurasian ruffe, Gymnocephalus cernuus, are benthivores that may compete for limited food resourc...

Simultaneous audio and video were recorded of a silver perch Bairdiella chrysoura producing its characteristic drumming sound in the field. The background noise contribution to the total sound pressure level is estimated using sounds that occurred between the pulses of the silver perch sound. This background contribution is subtracted from the total sound to give an estimate of the sound pressu...

The near-surface distribution of young-of-the-year perch was observed with a towed upward beaming echosounder system (SIMRAD EK60 with a circular 7◦ transducer). Perch aggregated densely in the epilimnion during daytime and dispersed evenly below the surface at night. Shoaling commenced in late June when perchmetamorphosed from the larval to juvenile stage. Average shoal widthwas 6.6m and avera...

There has been no previous parasitological survey of perch Perca fluviatilis in Turkey. Consequently, the objectives of the present study were to investigate the metazoan parasite communities of perch and also to calculate infection parameters of the parasites in a eutrophic lake. A total of 52 perch were collected seasonally from Lake Sığırcı in Ipsala, Turkey, between April 2009 and February ...

Due to altered biogeochemical processes related to climate change, highly colored dissolved organic carbon (DOC) from terrestrial sources will lead to a water "brownification" in many freshwater systems of the Northern Hemisphere. This will create deteriorated visual conditions that have been found to affect habitat-specific morphological variations in Eurasian perch (Perca fluviatilis) in a pr...

1. The effects of addition of juvenile perch (Perca fluviatilis) on the microcrustacean and rotifer communities associated with nymphaeid beds were studied, at three different plant densities [high (normal), medium (reduced by a half) and low (reduced to a third of normal)], in eighteen 2 m 3 1 m enclosures in a shallow lake. 2. At the low and medium densities of lilies, Daphnia densities were ...

The purpose of this study was to evaluate the effects of environmentally relevant dietary MeHg exposures on adult female yellow perch (Perca flavescens) and female zebrafish (Danio rerio) ovarian development and reproduction. Yellow perch were used in the study for their socioeconomic and ecological importance within the Great Lakes basin, and the use of zebrafish allowed for a detailed analysi...

Understanding the resilience of aquatic ectothermic animals to climate warming has been hindered by the absence of experimental systems experiencing warming across relevant timescales (for example, decades). Here, we examine European perch (Perca fluviatilis, L.) from the Biotest enclosure, a unique coastal ecosystem that maintains natural thermal fluctuations but has been warmed by 5-10 °C by ...

In the present paper, we report on the use of adsorptive transfer stripping technique in connection with chronopotentiometric stripping analysis for metallothionein determination and of differential pulse anodic stripping voltammetry for lead detection in tissues of wild perch (Perca fluviatilis, n = 6) from the Svratka River in Brno, Czech Republic. Primarily, we determined the content of MT i...