Meeting Abstract
P1.219 Friday, Jan. 4 Small Diel Temperature Increases Affect the Time to Metamorphosis in the Arizona Tiger Salamander (Ambystoma tigrinum) Alone and in Combination with Ammonium Perchlorate Exposure PARK, D.*; DANIELS, K.D.; FREEL, K.L.; PROPPER, C.R.; Kangwon National Univ., South Korea; Northern Arizona Univ., Flagstaff; Northern Arizona Univ., Flagstaff; Northern Arizona Univ., Flagstaff parkda@kangwon.ac.kr
To determine if small diel water temperature increases affect the developmental process of the Arizona tiger salamander alone and/or in combination with endocrine disrupting compounds, larvae of developmental stages 8-13 (Watson and Russell, 2000) were exposed to 0, 20, or 200 ppb ammonium perchlorate (AP), a known thyroid hormone disruptor and maintained at ambient temperature (control) or increased 0.9 oC (daily mean temperature) above ambient temperature for 11 weeks in outdoor enclosures. Developmental stage, body growth, and startle response of the larvae were measured at the end of each exposure week. The date of metamorphosis was also recorded for each larva. At collection the following measurements were taken: head size, snout-vent length, body mass, thyroid gland size, and gonad mass. The results demonstrate that an increase in diel water temperature and exposure to AP affect the time to metamorphosis during a specific time period and interact with each other. At ambient temperature, 20 ppb AP exposure shortens the time to metamorphosis, but at increased diel temperature, AP does not affect metamorphic timing. Increased diel temperature shortens the time to metamorphosis. In addition, temperature had no effect on gonadosomatic index, but 200 ppb AP exposure decreased gonad mass. We did not observe any significant differences between treatments in the remaining measurements collected. Our results suggest even small shifts in climate such as small diel temperature increases affect the developmental process of salamanders in the field. Furthermore, this shift could interact with exposure to common pollutants that interact with the endocrine system and affect development.
