After male spotted salamanders emerge from hibernation and arrive at their ancestral breeding (vernal) pools, they cluster in groups called congresses, await the arrival of females, pair up with one and then the pair performs a courtship dance.
Unlike some species of amphibians, the male spotted salamander does not fertilize the eggs as the female lays them. Rather, she collects his sperm into her body and internal fertilization takes place. When the female is sufficiently stimulated, the male deposits up to 80 spermatophores (pyramid-shaped plugs of mucus with a sperm capsule at the top), often on a submerged branch. The male maximizes the chances of insemination by depositing many scattered spermatophores, covering every spermatophore he encounters, even his own, with a new spermatophore. In so doing, he increases his spermatophore count, while simultaneously eliminating a rival’s spermatorphores. The female then crawls over a spermatophore and positions her vent, or cloaca, so as to allow the lips of her cloaca to detach the sperm capsule.
Within a short period of time the salamanders retreat back to the woods, rarely to be glimpsed until next spring’s breeding season. (Photo: spotted salamander spermatorphores, with sperm capsule missing on far left spermatophore)
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