Irreversible climate change will also change environmental assessment and management

✍ Scribed by John Cairns Jr

• Publisher: Society of Environmental Toxicology and Chemistry
• Year: 2010
• Tongue: English
• Weight: 66 KB
• Volume: 6
• Category: Article
• ISSN: 1551-3777
• DOI: 10.1002/ieam.24

✦ Synopsis

and the density of spawning males, and are highly variable in free-spawning species. Populations under conditions of both sperm competition (high density) and sperm limitation (low density) have been recorded. This leads to what is known as the Allee effect, with higher population densities experiencing higher reproductive success due to higher fertilization rates outweighing any cost of competition or polyspermy. A contaminant that reduces sperm swimming speeds, e.g., copper (Hollows et al. 2007) or WAF, reduces the sperm concentration around an oocyte and, thus, effectively increases sperm limitation. This exacerbates the Allee effect by effectively reducing the distance between spawning males at which fertilization success is ensured. Contaminantinduced effects on fertilization success are likely to be greater during natural spawning events than those measured in the laboratory at equivalent exposure concentrations due to lower, variable sperm concentrations. Lower density populations will be at greater risk of reproductive failure than high density populations.