I now know at least a little bit about newts. Karen Goetz, with beautiful photographs, introduced us to the natural history of the California Newt (Taricha torosa). Karen, as part of her graduate studies in Conservation biology, had studied how female newts selected their egg laying sites in the hills of the East Bay.
She lead with the life cycle of these amphibian’s (a type of salamander in fact): from their start as eggs the size of o large cherry, through their larval stage on into their adult life, their mating habits, and how they lay eggs, growing 6-8 inches, with toxins in their skin, and living for a surprisingly long time (20 years at least in the wild, with a record of 35 in captivity). Despite their toxic skin, they still have their predators, crayfish and garter snakes, and other newts as well.
What Karen had studied in particular was where the female salamanders lay their eggs. It turns out they tend to lay their eggs in deeper pools (greater than 37cm in depth), on woody objects of 9mm diameter or greater, near muddy banks. Her hypothesis being that their choice relates a lot to biomechanics — how eggs fare in the seasonal flooding of California creeks: eggs fare best when laid on woody branches resilient to turbulent waters, and deep enough that they would avoid being hung out to dry before the eggs hatched.
Her pictures from under the water were ethereal glimpses of the lives of these animals. Probably the part we know best, as when they crawl out from the creek, there’s not a lot of data of how far, or doing what. We do know that newts, like many other amphibians, are vulnerable because they are so dependent on water for such a crucial part of their life. Humankind has had a huge impact in what it has been putting into the water, as well as how the water flows.
SF Natural History Series 