My walks in Eliza Howell Park in the second half of April always include stops at the “Toad Breeding Pond.”
When the weather gets to be just warm enough, male American Toads, having recently emerged from hibernation, head to the pond to call in females. I expect to hear/see them within a few days of April 20 (either before or after), usually beginning the day following a “warm” night rain.
On April 17 this year, there was a light rain at about 9 p.m. when the temperature was about 51 degrees, which counts as “warm,” and some toads were, in fact, present on April 18. The active breeding did not really begin until April 21, however, because the weather turned colder. The temperature did not get above 44 degrees on April 19 and April 20, too low for these cold-blooded animals to think about breeding.
The next three days (April 21, 22, 23) were warmer and filled with the loud calling of many voices and lots of activity, even in daytime.
Note: This toad photo and the next 3 below are courtesy of Margaret Weber
For 51 weeks in the year, toads are solitary and nocturnal (and they hibernate in burrows individually from November to April). During the brief breeding season, however, the sexually mature (2 or more years old) return to their natal pond, where the males compete in attempting to attract females by their calls.
Some time is spent, of course, in considering the options or the competition.
In mating, the male attaches himself to the back of the female and, while she lays eggs in the water (in strings), he releases sperm. Fertilization takes place outside the body.
In 3 – 12 days (depending upon the temperature), the eggs hatch and the resulting tadpoles will spend up to 2 months in the pond before they complete metamorphosis and are able to leave the pond. Only a very small percentage survives the first year.
Last year egg-laying was later, followed by cold weather which delayed hatching. Then there was a May hot spell, leading to the drying up of the pond before the tadpoles were able to survive on land. (See “American Toad Breeding Pond: the 2018 Story,” July 23, 2018.)
So I was pleased to hear from another member of the Eliza Howell frog/toad survey team on April 21 this year that toads were calling in a different location in the park, an annually flooded area by the edge of the road, a spot that I am creatively identifying as “Toad Breeding Pond 2.” I don’t know how many years toads have been using this location, but they were present in large numbers this year and will probably continue to do so in the future.
Typically, toads are loud and active in the breeding pond for 3-4 days. On April 24, all was quiet in both ponds. The adults have now gone their separate ways – till next April – catching insects mostly at night (the estimates are that one toad eats about 10,000 insects in the summer season), and hiding under leaves or logs in the daytime.
And I, instead of watching breeding adults, I hope to be watching tadpoles soon.