Looking for a researcher to analyze newt roadkill data

I’ve seen trends in the newt roadkill data that I think would make an interesting topic for study. I’m wondering if a professional herpetologist or college student would be interested in analyzing this roadkill data to further our understanding of these two species (Taricha torosa and Taricha granulosa) and publish a paper about it.

Here's what I’ve noticed and find interesting:

  1. I’ve read that newts mostly migrate on rainy or foggy nights. However, the data show there is significant roadkill on all days during migration season – including after extended periods with no rain (8-10 days). When I plot number of roadkill against amount of rainfall, I find no correlation at all. In fact, some of the highest roadkill numbers came on days when there was no rain.
  2. Temperature, more so than precipitation, seems to determine the number of newts on the road. I've noticed a significant drop in fresh roadkill when the temperature dips into the low 40's F and below (and when there was snow on Mt. Umunhum). Unlike rainfall amount, there is a definite correlation between low temperature and roadkill numbers. Someone with a biostatistics background would be able to determine just how strong the correlation is.
  3. I’ve also seen a considerable number of live newts during the daytime (~70 this season during my 2-4 hr surveys). A friend in Fresno has recorded in her journal 384 live newts she's seen in the daytime this season. This could be significant for those planning roadkill mitigations. Closing roads only on rainy nights might leave hundreds of newts susceptible to roadkill during the daytime.
  4. I’ve heard that newts of the species T. granulosa do not tend to migrate. The data show otherwise. They’re being killed in large numbers right alongside T. torosa.
  5. Predation: I've read that garter snakes are the only newt predators. However, I've seen crows eating newt roadkill and on several occasions and I've seen dead beetles on top of dead newts.

"One of the most toxic species of newts, the Taricha newt, is known to only be able to be eaten by the garter snake as it is too poisonous for any other predators."
https://www.joyofanimals.com/what-predators-eat-newts/
Yet this article goes on to say:
"The mosquitofish (Gambusia affinis) and red swamp crayfish (Procambarus clarkii) have caused the greatest reduction in newt populations."

"Toxin-resistant garter snakes are the only known animals today that can eat a rough-skinned newt and survive."
https://en.wikipedia.org/wiki/Rough-skinned_newt

  1. Early on, when taking pictures of the roadkill, I was faced with the problem of how to identify fresh roadkill versus carcasses I had already photographed during a previous survey. So I started a study of the decomposition of newts, collecting data from week to week. There is some interesting stuff in there too. Also, this data may help others who are on the same quest to save the newts from extermination. It will help them collect accurate roadkill counts.
  2. I’ve seen many instances of what look like egg masses surrounding the carcasses. The interesting thing is that these masses continue to grow/expand even after the newt is dead.
  3. Diet: I’ve read that newts are primarily carnivorous, but I think they might eat Pacific Madrone berries too, which would make them omnivorous. See the following examples:
    https://www.inaturalist.org/observations/19751575
    https://www.inaturalist.org/observations/19721499
    https://www.inaturalist.org/observations/19721448

Posted by truthseqr truthseqr, March 10, 2019 12:17 PM

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