Toxicity of bog water to embryonic and larval anuran amphibians

✍ Scribed by Saber, Peter A. ;Dunson, William A.

• Publisher: John Wiley and Sons
• Year: 1978
• Tongue: English
• Weight: 728 KB
• Volume: 204
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402040104

✦ Synopsis

Abstract

A survey of the amphibians of a north temperate zone bog revealed that a number of species common in suitable locations nearby were absent from the bog. Several species of anuran larvae and embryos suffered high mortality when placed in the naturally acidic stream draining the bog. Mortality of bullfrog larvae (Rana catesbeiana) placed at a number of sites along the natural pH gradient (pH 3.9–6.6) formed by this stream was significantly greater than in those placed in a clearwater control stream (pH 6.6–6.9). This lethality of stream water even at moderate pH's near 6.0 indicates that a toxic factor other than acidity may be involved. In the laboratory, mortality of clawed frog (Xenopus laevis) embryos was significantly greater in unaltered bog water (pH 4.0–4.3) than in bog water neutralized with sodium hydroxide or in charcoal filtered tap water. The latter two conditions did not show significant mortality differences. This implies that low pH is the principal source of toxicity for Xenopus.