The other night was one of those almost summer kind of nights. It was stuffy in the house but too early to turn on the air-conditioning. For crying out loud - it wasn't even May yet! So I opened up the sliding glass patio door and was greeted by a lovely chorus of toads that have taken over the backyard pond that I built with my son, Sean several years ago.
Shortly, I heard my wife call from the kitchen, "I hate toads!" Most of the year the backyard pond is a lovely little place with a happy little stream that flows along down through the flower garden and waterfalls into the pond providing soothing gurgling water sounds. But right now, it has received its annual toad invasion.
Toads are harmless, vocal and valuable. While I might be able to convince my wife that they are harmless, there is no problem in convincing her that they are vocal. The one big hurdle that I have would be to try and convince her that they are valuable. Right now, during their spring mating season, I'm afraid our backyard toads are not considered valuable, but in danger if my wife can do anything about it.
Most people probably do not give toads much thought, but we need these amphibians to control destructive insects and to add their voices to the sounds of spring and summer nights. (Remember I wrote this my wife would not agree.) Their role in nature can be illustrated by the huge number of insects they eat. Since their bodies readily take in contaminants, they are good indicators of environment health. Amphibian skin secretions also are used in medical research to control and cure human diseases.
All toads must return to a body of water to reproduce. The toads that are in our backyard pond are American Toads. They are head and shoulders, far and away the most common toads we have here in Iowa. They breed in early spring. That's why they are living at our pond right now. Some adventurous males chose our pond when the temperature and humidity was suitable and began to sing (my choice of words not my wife's). That entices females to join them and select a mate. Soon, other males congregate and add their voices to the chorus. As females, heavy with eggs, enter the pond, they are grasped by a male in an embrace called amplexus and begin the process of egg-laying. Fertilization is external. He will retain his firm grip on her until all the eggs have been laid.
Most eggs hatch within 10 to 14 days of being laid, but they may hatch much sooner if the water temperature is above 70 degrees F. The tiny, newly hatched tadpoles rest for a few days by clinging to aquatic plants, receiving nourishment from the last of the yolk sac stored in their bellies. Relatively few of the thousands of tadpoles will see adulthood.
To escape a predator, toads defend themselves by producing toxic or unpleasant tasting skin secretions that are released when the animal is seized. Due to their toxic skin, toads are not a popular food among most predators. Of course, this method of defense is not the best one in my opinion. To understand that toads are bad tasting, this generally requires that predators must chomp down on a few before they learn that valuable lesson. It means that some toads have to take one for the team.
Peoples' hands normally are not affected by the skin secretions of toads and frogs, though human eyes are sensitive to these substances. The pain and burning that result when even a slight amount of skin secretion gets in one of your eyes is something that I am told you will never forget.
So you can see that it is important to wash your hands after handling a toad, or frog. But the age old myth that toads can cause warts on people is still false.