Pollution-induced behavioural effects in the brown bullhead (Ameiurus nebulosus)

Abstract

Aquatic ecosystems are major sinks for pollutants which can have adverse effects on biodiversity. Thus, it is important to understand the nature of pollution-induced change in aquatic ecosystems. We show that brown bullheads (Ameiurus nebulosus) may have evolved in response to chronic pollution exposure. We collected adults from the Detroit River (polluted site) and Belle River (control site). Both adults and common-garden raised juveniles were tested for aggression, locomotion, and escape response using consecutive unchallenged (clean) and challenged (polluted) trials. Detroit River fish were more aggressive than Belle River fish when challenged. Furthermore, Belle River fish showed increased locomotion when exposed to pollutants, whereas Detroit River fish were unaffected. The consistent difference in adult and juvenile behaviour across trials suggests a genetic response to pollution. Escape response on the other hand, showed inter-population differences, but no consistency between adults and juveniles, indicating that this behaviour is influenced by non-genetic factors. We discuss our data with respect to the potential adaptation of populations to pollution and the implications for prioritizing remediation efforts.

The effects of elevated temperature on the sexual traits, immunology and survivorship of a tropical ectotherm

“…Digital images were recorded using an SI-C400N microscope video camera (Costar Imaging, Lakewood, CA, USA) for velocity analysis. Following methods outlined previously (Breckels and Neff, 2010), we extracted images from the recorded video at 10framess -1 and determined the two-dimensional coordinates using NIH ImageJ software (http://rsbweb.nih.gov/ij). Using the Pythagorean theorem, the distance travelled (μm) by a sperm cell in 1s was calculated as the sum of the distances travelled between the 11 consecutive frames in that second.…”

The metabolic, locomotor, and sex-dependent effects of elevated temperature on Trinidadian guppies: limited capacity for acclimation

“…Burst speed was quantified using methods similar to those described elsewhere (Breckels and Neff, 2010). Images (captured at 30framess -1 ) were extracted from the videos using Picture Motion…”

Behavior as biomarker? Laboratory versus field movement in round goby (Neogobius melanostomus) from highly contaminated habitats

“…In fact, studies of behavioral impacts on naturally exposed individuals, or tests for consequences of exposures in more natural settings are rarely performed (see Weis et al 2001;Grue et al 2002;Breckels andNeff 2010 andCandelmo et al 2010 for notable examples). The results of acute laboratory exposures do not always capture the consequences of the chronic exposures common in the wild.…”

“…Contaminants known to be at problematic levels in the Harbour (''A list'' contaminants) are polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and metals including arsenic, cadmium, lead, iron, mercury and zinc, and the Harbour is also the recipient of discharges from four urban wastewater treatment plants (Hamilton Harbour Remedial Action Plan (RAP) 2003). PAHs (Goncalves et al 2008;Gravato and Guilhermino 2009), PCBs (Nakayama et al 2005;Schmidt et al 2005), mercury (Zhou and Weis 1998), cadmium (Honda et al 2008), as well as complex combinations of contaminants (Triebskorn et al 1997;Breckels and Neff 2010) can all affect locomotion.…”