The 2014 egg mass counts are complete, and it looks like it's going to be a productive year for wood frogs and spotted salamanders! Most of the wood frogs have hatched over the past few weeks, but the salamander embryos are still developing. The two egg masses can generally be distinguished by their shape and size. Wood frog egg masses are usually located at or near the surface, with black embryos visible inside the mass. Spotted salamanders usually attach their egg masses (which are typically smaller than wood frogs') to submerged vegetation and sticks. The salamander egg masses can also be identified by an outer jelly-like coating around the entire mass. Toads also lay their eggs in vernal pools in long strands.
Photo credits: T. Youker
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| Strand-like egg mass of the American toad (Anaxyrus americanus) | | | |
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| Spotted salamander (Ambystoma maculatum) egg mass, with visible outer jelly coating |
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| Wood frog (Lithobates sylvaticus) egg mass |
Egg masses often appear greenish due to the growth of a symbiotic algae,
Oophila amblystomatis. This algae is thought to aid in the circulation of oxygen to the developing embryos. Once the eggs hatch, emerging tadpoles feed on the remaining yolks, egg sacs, and algae. Below is a video of wood frog tadpoles hatching in one of the open field pools.
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| Wood frog tadpoles munching on their empty, algae-covered egg mass |
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