Influence Of Water Chemistry And Predator Communities On The Egg Mass Polymorphism Of Ambystoma maculatum

Spotted salamanders (Ambystoma maculatum) migrate each spring to temporary ponds to mate. The females lay their eggs in two morphs: clear and opaque. The presence or absence of hydrophobic protein crystals in the egg mass jelly influence whether the mass will be clear or opaque. Previous studies have hypothesized that water chemistry and predator communities may influence which color polymorphism is more prominent in a site by creating the ideal environment for one of the egg mass morphs. For this study, I examined associations between water chemistry, predator communities and egg mass morphology. I measured water chemistry, the abundance of clear and opaque egg masses at three sites in Watauga County, North Carolina each with multiple breeding ponds (n=16). Additionally, in each pond, I used aquatic light traps to sample vertebrates and invertebrate communities during both the spring and late summer. The proportion of clear egg masses ranged from 0-58.5%. However, I found no significant relationship between water chemistry or predator communities and the proportion of clear egg masses. These results suggest that the frequency of egg mass polymorphisms in Watauga County breeding ponds appears unrelated to water chemistry or predator communities.