[obol] kingfisher diet? [and Rough-skinned Newts]

[Range Bayer]

Hi,

    Darrel's observation's of the kingfisher with a rough-skinned newt 
(Taricha granulosa)is fascinating.  The following is derived from an
account written by Kathy Merrifield in the March 2007 newsletter of
Yaquina Birders & Naturalists may be of interest about newts:

     ...  My [Kathy Merrifield's] only contribution was to suggest to
Betty Bahn that she avoid swallowing any rough-skinned newts, because
they're supposed to be poisonous.  I related a story from OSU's
legendary (retired) Dr. Storm, who said that at a memorable party,
drunken students were dared to swallow rough-skinned newts.  They
swallowed them and suffered no ill effects.  Maybe the toxin is
soluble in beer.

    Betty replied that she has played with and handled rough-skinned newts
since childhood with no ill effects.  But then, two men on the Owyhee
River about 20 years ago, she said, accidentally boiled a couple of
newts in their morning coffee, which had been prepared the night
before and reheated.  They died before they could even reach their
boat.  The cause of death was unknown until the newts were discovered.

   Because I was confused regarding the toxicity of rough-skinned newts, I
e-mailed a herpetologist in the OSU Dept. of Zoology, Bob Mason. 
(Herpetologist = student of reptiles and amphibians.)  Here's what he
said, only slightly paraphrased.

   Yes, there are a lot of tales about the rough-skinned newt.  And
actually, there probably is truth in all of them.  This species really
is quite poisonous when ingested.  You can play with them all day long,
and the amount of tetrodotoxin you will transfer to your skin is
negligible.  If you wash your hands, you wash it all off.  Now, if you
eat a newt, and drunk MEN (usually!) do this on occasion, you certainly
can die.  That's if you pass out or wait a long time until the
neurotoxin has done its irreversible damage.  There is no antidote to
the poisoning.  So, that part is definitely true.

   The interesting part of the story, he continued, is that the toxicity
of the newts varies across the population's considerable range.  In
some areas, they are barely toxic.  In other parts, including Benton
County and part of Lincoln County, there are highly toxic individuals. 
The way we know this is that red-spotted garter snakes can feed on the
newts and not die.  Our particular snakes right here in the greater
Corvallis area are extremely resistant to the toxins, because the newts
here are very toxic.  So, take the same species of snake from say,
Portland, and feed it one of our newts, and it would die very quickly. 
The newts in Portland are not nearly as toxic as ours.  This shows is
that there is a sort of "arms race" between the newts and the garter
snakes.  The newt gets increasingly more toxic to defend itself from
garter snake predation, and the garter snakes have to evolve more and
more resistance, so then the newt evolves greater toxicity, and so on.

   So, said Bob Mason, that's why I say that probably all the stories are
true.  I always tell people that even our newts can be handled very
safely; just wash your hands before you eat.  Even if you didn't wash,
the tetrodotoxin dose would be miniscule.  Now if you lick one of our
newts, your tongue and lips would go numb for a few hours or even a day
or two.  So I don't recommend it...

    Cheers,

Range Bayer, Newport

On Sat, June 16, 2007 7:18 am, Darrel Faxon said:
> OBOlites,
>     Yesterday I saw a couple of just fledged Belted Kingfishers at our
> pond.  One appeared to be trying to swallow something, which looked
> orange, and I think it succeeded.  A little later I saw the same bird
> fly down and pluck a Rough-skinned Newt out of the water.  It flew
> back to the limb, and tried eating this one for a while before
> spitting it out.  I know these that one of these newts has enough
> poison to kill a man.  Would eating one kill a kingfisher, or are the
> birds immune to the toxin?  What about herons?  Can and do they eat
> newts?  I can't remember ever seeing a bird of any kind try to eat a
> newt before.
>
> Darrel_______________________________________________
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