It's one of those quiet nights. The moon is trying to fight its way through clouds overhead, and much of the previous day was rainy. Though it isn't quite foggy, there is a great deal of humidity in the air and the temperature is somewhere in the 50s. It is midspring and I think all of us are happy to see winter behind us. To the east of my house, past the edge of the woods where I sometimes see deer and turkeys blink into and out of existence, there are hidden pools of clear water. These pools started as accumulations of melting snow, but warm spring rains sustain them. I've never actually visited these pools, because I don't own the property on which they rest, but I know where they are because of the quiet and comforting chorus that rings out from their depths. Predictably, spring peepers are the loudest of the performers. Mixed in with the peepers, however, there are other, less-familiar songs. Unlike the brief, loud notes of the peepers, these are more subtle, sustained notes generated by a different species. More like trilling whistles than anything else, these are the songs of American toads. Together, the two species put on a performance that can easily lure me out into the dark for hours on end. I find as much pleasure basking in the sound of their voices as other people may find basking in the warmth of the sun during the day. As is the case with most birds, it is the males that do all of the singing. I don't think I've ever heard the first song of the season, but at some point, sooner or later, one male breaks the silence of winter with the first note of the new year. This song indicates that standing water has been located, and it attracts other toads within earshot. As the numbers grow so does the volume until you eventually get to a point where the songs can travel quite a distance across the landscape. Then, as the males put on their best performances, the females start to arrive. It may seem odd to imagine toads swimming, but they are quite good at it and each female will swim from one male to the next and listen to each song quite carefully. As soon as a particular female encounters a particular male whose sound she likes, mating will commence. The problem is that the males are quite competitive and they can be surprisingly aggressive. Basically, any toad swimming by is a target for the love-blind intentions of the overly excited minstrels. Females have to be quick if they are not to be mobbed. Amusingly, this also means that males have to watch out for themselves as well. I have observed many a false mounting and laughed as the waylaid victims of this overzealous ardor go through the motions of saying, 'what the hey!' Any female that allows herself to be caught may find herself the object of great interest from many males. Then the fight is really on and the females seem to endure the whole process with a sort of bored patience that many a human female may experience at cocktail parties. Female toads simply have to endure the wrestling matches while the males sort out who the winner will be. Sooner or later a winner will emerge as male takes up position behind the female and cannot be dislodged by any challenger. This configuration of male and female is known as 'amplexus' and it is a requirement of frog and toad mating because the eggs are fertilized externally. Once in place, the male just hangs on for all he's worth while the female gets to the business of finding a place to lay her eggs. For a toad, the ideal position for eggs is on a piece of submerged vegetation in water that is deep enough to avoid any danger of drying up. Since eggs are attractive food items, the female will tend to avoid bodies of water with permanent populations of fish. This is why the seasonal, or 'ephemeral,' pools that fill with water in the spring are so attractive. Toads just need the water for breeding, so they don't really care if the pools dry up by midsummer. The eggs of toads can be differentiated from those of frogs and spotted salamanders because they are extruded in strings, rather than in semi-spherical masses. The development of toad eggs is just the same as those of frogs, from pollywog to tadpole, to baby toads with tails, to fully-formed little toads. Then, they leave the water behind and disappear into the surrounding woods and fields, only to return again the following spring to lend their voices to the chorus of life. (Bill Danielson is a freelance writer living in Altamont, N.Y. He has worked as a professional naturalist and environmental researcher; he teaches high school chemistry and biology in Pittsfield, Mass. Send your questions about the natural world to him at billd@speakingofnature.com.) 