Lethal And Sublethal Effects Of Elevated Salinity On The Larvae Of Anaxyrus Terrestris, Hyla Squirella, And Gastrophryne Carolinensis

Bailey Fallon

School Name

Governor's School for Science and Math

Grade Level

12th Grade

Presentation Topic

Zoology

Presentation Type

Mentored

Mentor

Mentor: Dr. Welch; Department of Biology, College of Charleston

Oral Presentation Award

1st Place

Written Paper Award

1st Place

Abstract

Salinization of freshwater habitats is a concern for aquatic organisms. As salt concentrations in freshwater increase due largely to anthropogenic causes, many freshwater species are becoming exposed to elevated salinity levels. Amphibians are of particular concern because their permeable skin and fully aquatic eggs and larvae bring them in direct contact with the aquatic environment. Consequently, studies investigating the effects of elevated salinity are necessary to determine the susceptibility of these species to the newly altered ecosystems. In the present study, tadpoles of the species Anaxyrus terrestris, Hyla squirella, and Gastrophryne carolinensis were exposed to several salinity concentrations to test the lethal and sublethal effects of such conditions. Salinities of 8 ppt (parts per thousand) and above were completely lethal for all three species. At 6 ppt, survival was diminished for all three species, though survival of Hyla squirella was also low at 0.4 ppt. Tadpoles of Gastrophryne carolinensis and Hyla squirella showed reduced growth at 4 and 6 ppt. Hyla squirella tadpoles also showed reduced activity at 6 ppt. These results suggest that salinities of 4 ppt and higher can negatively affect these amphibian species in the tadpole stage, although individual variation exists in salinity tolerance. Consequently, salinization of freshwater habitats due to anthropogenic causes poses a potential threat to these species in their natural environment.

Location

Kinard 119

Start Date

4-16-2016 11:45 AM

COinS
 
Apr 16th, 11:45 AM

Lethal And Sublethal Effects Of Elevated Salinity On The Larvae Of Anaxyrus Terrestris, Hyla Squirella, And Gastrophryne Carolinensis

Kinard 119

Salinization of freshwater habitats is a concern for aquatic organisms. As salt concentrations in freshwater increase due largely to anthropogenic causes, many freshwater species are becoming exposed to elevated salinity levels. Amphibians are of particular concern because their permeable skin and fully aquatic eggs and larvae bring them in direct contact with the aquatic environment. Consequently, studies investigating the effects of elevated salinity are necessary to determine the susceptibility of these species to the newly altered ecosystems. In the present study, tadpoles of the species Anaxyrus terrestris, Hyla squirella, and Gastrophryne carolinensis were exposed to several salinity concentrations to test the lethal and sublethal effects of such conditions. Salinities of 8 ppt (parts per thousand) and above were completely lethal for all three species. At 6 ppt, survival was diminished for all three species, though survival of Hyla squirella was also low at 0.4 ppt. Tadpoles of Gastrophryne carolinensis and Hyla squirella showed reduced growth at 4 and 6 ppt. Hyla squirella tadpoles also showed reduced activity at 6 ppt. These results suggest that salinities of 4 ppt and higher can negatively affect these amphibian species in the tadpole stage, although individual variation exists in salinity tolerance. Consequently, salinization of freshwater habitats due to anthropogenic causes poses a potential threat to these species in their natural environment.