Elevated Maintenance Costs in an Anuran (Rana catesbeiana) Exposed to a Mixture of Trace Elements during the Embryonic and Early Larval Periods

Abstract

We investigated the relationship between maintenance costs (standard metabolic rates, measured as O2 consumption at rest) in tadpoles of the bullfrog, Rana catesbeiana, and exposure to contaminants in a coal ash-polluted habitat (characterized by a variety of trace elements). We compared metabolic rates of tadpoles collected from the polluted site with those from an unpolluted reference pond. Tadpoles collected in the polluted site had 40%-97% higher standard metabolic rates than those collected from the reference pond. We also reciprocally transplanted eggs of the bullfrog between the polluted site and another reference pond and compared standard metabolic rates of tadpoles at 25 and 80 d posthatching. Metabolic rates of tadpoles raised in the polluted site were from 39% to 175% higher than those raised in a reference pond, depending on tadpole age and temperature at which metabolic rates were measured. There were no effects of site of origin of the eggs (polluted or unpolluted) on metabolic rates. Survival to hatching did not differ between sites, although survival to the end of the experiment (80 d posthatching) was lower in the polluted area than in the reference site. Surviving tadpoles were larger in wet body mass in the polluted site than in the reference pond, possibly due to lower survival in the former, but there was no relationship between survival and metabolic rate. It is clear that some feature of the polluted habitat was responsible for causing substantial elevation of standard metabolic rates of tadpoles. We hypothesize that the mixture of trace elements present in sediment and water in the polluted site was responsible for the observed physiological differences.

Respiratory and Reproductive Characteristics of Eastern Mosquitofish (Gambusia holbrooki) Inhabiting a Coal Ash Settling Basin

“…The lack of effect on SMR contrasts previous work (Rowe et al 1998Hopkins et al 1999) in which other diverse organisms (bullfrogs, banded water snakes, and crayfish) collected from the ASH system exhibit SMRs (mL/g ⅐ h) approximately 23-32% higher than conspecifics from reference sites. Given that SMR is an indirect measure of an organism's maintenance costs, the elevated SMRs of other ASH organisms suggested that they incurred energetic costs, perhaps as a result of energy required to facilitate toxicant elimination or repair toxicant-induced cellular damage (Calow 1991).…”

“…Prior to statistical comparisons, the highest 50% of SMR values for each individual were excluded from the dataset. The upper 50% of measurements were excluded to ensure that periods of activity were not included in the estimation of SMR (Rowe et al 1998) because SMR is a measure of an organism's metabolic rate at rest. The mean of the remaining 50% of measurements was then used as an estimate of SMR for each individual.…”

“…A number of fish species and other organisms have been documented to be sensitive to coal ash, a byproduct of coal combustion at electricity generation plants, and wastewater runoff from coal ash settling basins (Cherry et al 1976(Cherry et al , 1984Hopkins et al 1999Hopkins et al , 2000aHopkins et al , 2000bLemly 1985;Lohner et al 2001aLohner et al , 2001bLohner et al , 2001cRowe et al 1998). Of 20 fish species inhabiting Belews Lake, North Carolina prior to selenium (Se) contamination from ash basin drain water, 16 were extirpated from the lake apparently due to reproductive failure associated with the contamination (Lemly 1985(Lemly , 1997.…”

“…A variety of organisms (i.e. bullfrogs, Rana catesbeiana; banded water snakes, Nerodia fasciata; and crayfish, Procambarus acutus) exposed to conditions in ash basins located on the Savannah River Site (SRS), Aiken, South Carolina, exhibit increased SMRs, an indirect estimate of an organism's maintenance costs (Rowe et al 1998Hopkins et al 1999). Presumably an increase in SMR results from energetically costly processes associated with combating contaminant exposure (e.g., cellular repair mechanisms, elimination of contaminants).…”

Efeitos da poluição industrial sobre anuros (Amphibia) da Mata Atlântica

“…Além disso, a exposição a contaminantes pode gerar alterações na massa de órgãos internos, como fígado e rins (Arrieta et al 2004). Contaminantes podem também gerar alterações no desenvolvimento e no metabolismo, malformações e problemas de respiração e locomoção, com consequente redução na capacidade de evitar predadores, disputar recursos e se reproduzir (Carey & Bryant 1995;Rowe et al 1998;Selvi et al 2003;Forson & Storfer 2006;Söderman et al 2007;Hayes et al 2010).…”