Posts Tagged ‘tetrodotoxin’
“So, what do you think?”
This afternoon, my boyfriend dropped by the shop to show off his handiwork for our latest project. He has taken several small beer coasters, spray-painted them yellow, and had drawn a picture of a newt in between a warning that read, “CAUTION: NEWT CROSSING”. They were laminated and mounted on sharpened Popsicle sticks, ready to be placed along one of our favorite creekside trails. I have been known to waste an hour online researching amphibians, so of course I approved. We hoped that people would get a laugh out of the tiny road signs, but secretly, I was also hoping that the alerts would also encourage hikers to watch their steps.
San Luis Obispo is home to both the Rough-Skinned Newt (Taricha granulosa) and the California Newt (Taricha torosa). The two look very similar, but can be distinguished by the Rough-Skinned Newt’s smaller eyes with yellow irises and v-shaped palatine tooth pattern. Both can grow to a length of 8in with dark brown backs and bright orange undersides to indicate their toxicity. Known as “tetrodotoxin”, the poison (the same that is found in pufferfish) binds to sodium channels in nerve cells and can cause paralysis or death. While they are harmless to humans, some people have reported skin irritation after handling the animals, so it is highly recommended that those who touch the amphibian wash their hands very well after an encounter. Newts are preyed upon by the Common Garter Snake (Thamnophis sirtalis), one of the few species that shows resistance to their life-threatening chemicals, but have few other predators to worry about.
California Newts are more common to the coastal areas of our state, while the Rough-Skinned Newt has a range that extends upwards towards Alaska. Both inhabit the cool waters of ponds, lakes, streams, pools, and slow-flowing portions of rivers. Terrestrial juveniles and adults can be found in adjacent woodlands where you are most likely to spot them under logs, rocks, and in leaf litter. Rough-Skinned Newts are the most aquatic of the Taricha species, but can move to land for months or years at a time. The newts dine on amphipods (tiny aquatic crustaceans), insects, snails, leaches, worms and tadpoles. They breed during almost every month of the year, with low-level populations mating from February to May and higher-level populations copulating from the spring to early fall.
Currently, the California Newt is listed as a California Species of Special Concern, as their numbers have declined due to the introduction of non-native species, pollution, and human development. If you are lucky, you might be able to catch a glimpse of one of these amazing creatures during wet weather or on a trek through your nearest watershed ecosystem. Keep an eye out for signs of prime newt habitat!