Sunday, April 3, 2016

American Toads (Anaxyrus americanus) & Eggs

March 9th. A creek runs behind our home. Periodically the floodplain above it floods during heavy rains. In either December or January, Upland Chorus frogs (Pseudacris feriarum) breed in shallow water containers around the house. It occurred to us that, if we dug a pond on the floodplain above the creek, we could encourage Upland Chorus frogs to breed there. 

So, W has been digging a shallow pond, expanding it during the dry summer months. It’s not particularly pretty, but it has been a success, and for more than just the chorus frogs.

On a recent walk during the middle of the day, I found a…

pair of American Toads (Anaxyrus americanus) in amplexus (laying/fertilizing eggs) in the pond. The female is noticeably larger than the male.

They had obviously been at work for a considerable period of time. 

The eggs are laid in gelatinous strands. The gelatinous material is not visible around recently laid eggs, but absorbs water and swells to become clearly visible as sand attaches to it. This material will protect the eggs against dessication if the water level in the pond drops too low before the eggs hatch and the tadpoles can swim into deeper water. 

I made my way around the pond and found enlarged gelatin tubes from at least two to three previous rounds of egg laying. 

American Taods may lay several thousand eggs. Eggs may take up to two weeks to hatch and transformation from tadpoles to adults in about to months.  They reach reproductive age in two to three years. 

Here’s hoping we have a healthy populations of American Toads in our area before too long. 

Savahhan River Ecology Laboratory: American Toad (Bufo [Anaxyrus]americanus).

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