Understanding of the impact of chemicals on amphibians: a meta‐analytic review

Abstract

Many studies have assessed the impact of different pollutants on amphibians across a variety of experimental venues (laboratory, mesocosm, and enclosure conditions). Past reviews, using vote‐counting methods, have described pollution as one of the major threats faced by amphibians. However, vote‐counting methods lack strong statistical power, do not permit one to determine the magnitudes of effects, and do not compare responses among predefined groups. To address these challenges, we conducted a meta‐analysis of experimental studies that measured the effects of different chemical pollutants (nitrogenous and phosphorous compounds, pesticides, road deicers, heavy metals, and other wastewater contaminants) at environmentally relevant concentrations on amphibian survival, mass, time to hatching, time to metamorphosis, and frequency of abnormalities. The overall effect size of pollutant exposure was a medium decrease in amphibian survival and mass and a large increase in abnormality frequency. This translates to a 14.3% decrease in survival, a 7.5% decrease in mass, and a 535% increase in abnormality frequency across all studies. In contrast, we found no overall effect of pollutants on time to hatching and time to metamorphosis. We also found that effect sizes differed among experimental venues and among types of pollutants, but we only detected weak differences among amphibian families. These results suggest that variation in sensitivity to contaminants is generally independent of phylogeny. Some publication bias (i.e., selective reporting) was detected, but only for mass and the interaction effect size among stressors. We conclude that the overall impact of pollution on amphibians is moderately to largely negative. This implies that pollutants at environmentally relevant concentrations pose an important threat to amphibians and may play a role in their present global decline.

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     Shaffer HB, Clark JM, Kraus F. When molecules and morphology clash: a phylogenetic analysis of the North American ambystomatid salamanders (Caudata: Ambystomatidae). Syst. Zool. 1991;40:284-303.

     Not in our library

112. 112.

     Shinn C, Marco A, Serrano L. Inter- and intra-specific variation on sensitivity of larval amphibians to nitrite. Chemosphere. 2008;71:507-514.

     Not in our library10.1016/j.chemosphere.2007.09.054

113. 113.

     Sih A, Kerby J, Bell A, Relyea R. Response to Schmidt. Pesticides, mortality and population growth rate. Trends Ecol. Evol. 2004;19:460-461.

     Not in our library10.1016/j.tree.2004.06.006

114. 114.

     Skelly DK. Experimental venue and estimation of interaction strength. Ecology. 2002;83:2097-2101.

     Not in our library

115. 115.

     Smith DC. Adult recruitment in chorus frogs: effects of size and date at metamorphosis. Ecology. 1987;71:2313-2322.

     Not in our library

116. 116.

     Smith GR. Lack of effect of nitrate, nitrite, and phosphate on wood frog (Rana sylvatica) tadpoles. Appl. Herpetol. 2007;4:287-291.

     Not in our library

117. 117.

     Snodgrass JW, Casey RE, Joseph D, Simon JA. Microcosm investigations of stormwater pond sediment toxicity to embryonic and larval amphibians: variation in sensitivity among species. Environ. Pollut. 2008;154:291-297.

     Not in our library10.1016/j.envpol.2007.10.003

118. 118.

     Snodgrass JW, Hopkins WA, Broughton J, Gwinn D, Baionno JA, Burger J. Species-specific responses of developing anurans to coal combustion wastes. Aquat. Toxicol. 2004;66:171-182.

     Not in our library10.1016/j.aquatox.2003.09.002

119. 119.

     Sparling DW, Linder G, Bishop CA. Ecotoxicology of amphibians and reptiles. 2000.

     Not in our library

120. 120.

     Sparling DW, Fellers GM, Mc Connell LL. Pesticides and amphibian population declines in California, USA. Environ. Toxicol. Chem. 2001;20:1591-1595.

     Not in our library10.1897/1551-5028(2001)020<1591:paapdi>2.0.co;2

121. 121.

     Sparling DW, Sparling DW, Linder G, Bishop CA. Ecotoxicology of organic contaminants to amphibians. Ecotoxicology of amphibians and reptiles. 2000;461-494.

     Not in our library

122. 122.

     Stuart SN, Chanson JS, Cox NA, Young BE, Rodríguez ASL, Fischman DL, Waller RM. Status and trends of amphibians declines and extinctions worldwide. Science. 2004;306:1783-1786.

     Not in our library10.1126/science.1103538

123. 123.

     Tilman D, Fargione J, Wolff B, D´Antonio C, Dobson A, Howarth R, Schindler D, Schlesinger WH, Simberloff D, Swackhamer D. Forecasting agriculturally driven global environmental change. Science. 2001;292:281-284.

     Not in our library10.1126/science.1057544

124. 124.

     Veith M, Kosuch J, Vences M. Climatic oscillations triggered post-Messinian speciation of Wester Paleartic brown frogs (Amphibia, Ranidae). Mol. Phylogenet. Evol. 2003;26:310-327.

     Not in our library10.1016/s1055-7903(02)00324-x

125. 125.

     Vitousek PM, Aber J, Howarth RW, Likens GE, Matson PA, Schindlerm DW, Schlesinger WH, Tilman GD. Human alteration of the global nitrogen cycle: causes and consequences. Ecol. Appl. 1997;7:737-750.

     Not in our library

126. 126.

     Vredenburg VT. Reversing introduced spsecies effects: experimental removal of introduced fish leads to rapid recovery of declining frog. Proc. Natl. Acad. Sci. USA. 2004;101:7646-7650.

     Not in our library10.1073/pnas.0402321101

127. 127.

     Wake DB, Vredenburg VT. Are we in the midst of the sixth mass extinction? A view from the world of amphibians. Proc. Natl. Acad. Sci. USA. 2008;105:11466-11473.

     Not in our library10.1073/pnas.0801921105

128. 128.

     Watkins TB. Predator-mediated selection on burst swimming performance in tadpoles of the Pacific tree frog, Pseudacris regilla. Physiol. Zool. 1996;69:154-167.

     Not in our library

129. 129.

     Weisrock DW, Papenfuss TJ, Macey JR, Litvinchuk SN, Polymeni R, Ugurtas IH, Zhao E, Howkar H, Larson A. A molecular assessment of phylogenetic relationships and lineage accumulation rates within the family Salamandridae (Amphibia, Caudata). Mol. Phylogenet. Evol. 2006;41:368-383.

     Not in our library10.1016/j.ympev.2006.05.008

130. 130.

     Widder PD, Bidwell JR. Cholinesterase activity and behavior in chlorpyrifos-exposed Rana sphenocephala tadpoles. Environ. Toxicol. Chem. 2006;25:2446-2454.

     Not in our library10.1897/05-522r.1

131. 131.

     Wright PM, Wright PA. Nitrogen metabolism and excretion in bullfrog (Rana catesbeiana) tadpoles and adults exposed to elevated environmental ammonia levels. Physiol. Zool. 1996;69:1057-1078.

     Not in our library

132. 132.

     Zajc I, Arntzen JW. Evolutionary relationships among European newts (genus Triturus) as inferred from two mtDNA fragments. Eur. J. Physiol. 2000;439(Suppl):R21-R22.

     Not in our library

133. 133.

     Zhang P, Papenfuss TJ, Wake MH, Qu L, Wake DB. Phylogeny and biogeography of the family Salamandridae (Amphibia: Caudata) inferred from complete mitochondrial genomes. Mol. Phylogenet. Evol. 2008;49:586-597.

     Not in our library10.1016/j.ympev.2008.08.020

Reads

A person counts once a day per paper. We keep no cookie and no address: a reader is a hash that changes every day. Any month under five reads shows no number.