Readers’ wildlife photos

March 23, 2018 • 8:00 am

Reader John Riegsecker sent these photos on February 26; his notes are indented:

Saturday I photographed an American Kestrel eating a snake, which got me to thinking about a series of photos I made of a Ring-necked Duck (Aythya collaris) eating a rough-skinned Newt (Taricha granulosa).  I am not an expert on Newt identification, but I’m pretty certain that is correct. I knew that rough-skinned newts were poisonous, so I asked around and did some Googling. The first thing I found was that someone had died from eating one:

The second thing I learned was of an arms race between the newts who kept developing more poison, and garter snakes that ate them developing more resistance to the poison.  The third thing I learned was that the 
potency of the poison varied by location: most potent in the  Willamette Valley of Oregon and decreasing in potency as one goes north.

These photos were taken at Ridgefield, a wildlife reserve in Southern Washington, so it is unclear how poisonous the newt would  be, but there is a good chance that was the duck’s last meal.

When most people see one of these ducks they think it should be called a Ring-billed Duck.  The first photo is of a Drake and shows that, in fact, there really is a ring around the neck.

The other photos show the hen eating the newt.

18 thoughts on “Readers’ wildlife photos

  1. I bet the dinosaur ducks have some ability to deal with the newt poison so they do not succumb. Would a heron die?

    1. The old conundrum – if fatal, the ducks may never learn that the newt is bad, & so will continue to scoff them when they see them. Surely it is more advantageous to just taste disgusting?

      1. But…each duck that eats rough-skinned newts never eats another one (unless they have an immunity). So only the ducks that do not eat these newts survive to reproduce.

  2. Amazingly John’s pics above were scraped by Googlebot & put up in image search at 13:09 GMT – not far behind the post going up. WEIT must have high ‘crawlability’ or just happened to coincide with a bot visit.

    I’m having trouble with the duck being a dead duck! I read of a similar incident with a mallard duck on Bee’s, Birds & Butterflies & the naturalist reported the duck continued going about its business for some time after – no time given. This was in the Greater Olympia area, WA. Why didn’t the duck refuse the prey given the ‘orrible taste? Could there be a rough-skinned newt imposter species that’s evolved too? One that’s all curtains & no furniture?

    Here’s Carl Zimmer on this arms race. Good article.

    1. Did some perusing online, and found that besides the toxic rough-skinned species, T. granulosa, there is a related species, T. torosa which is also toxic. That species is mimicked by a harmless model, Ensatina eschscholtzii. Hope I got that right.

  3. That is very interesting! But it seems possible that the newt was not from a humongously toxic population. And if it was in the water perhaps whatever toxins it had were well diluted. Just a guess.

  4. Just day before yesterday I saw a lovely garter snake in our forest, and yesterday a rough skinned newt! This was my first sighting of either this year- it is finally warming up I suppose.
    If I recall correctly, the snake takes a hit from the poison, and begins to move very slowly. I have wondered if it is then eaten by a bird whether the TTX gets the bird too?

  5. Yikes, that was a dramatic set of photos. I had no idea newts were in danger from certain ducks. Around those parts, it would be more advantageous to be a vegetarian duck…or a filter feeder.

Leave a Reply