March 10, 2003, 2-4:00pm
10?C, 3SW, Drizzle
Jay?s Pond, SW of Deer Harbor
Orcas, Island

How do they do that?

Three pairs of Ring-necked ducks, Four pairs of Buffle-heads, a lone
drake Mallard and a female Hooded Merganser were being observed, at
about 30 meters, on Jay?s pond . The diving ducks were actively
feeding when the HOME came up with an adult rough-skinned newt (Taricha
granulosa). Jay?s pond has a large population of these newts, which
have been observed there for many years.

The toxicity of this newt is well documented. Several years ago an
Oregon college student died, when on a dare, he swallowed a
rough-skinned newt. The tetrodotoxin or TTX is a dangerous neurotoxin
to mammals and is similar to that found in puffer fish and the
blue-ringed octopus. The toxin in one newt has been estimated to be
sufficient to kill several humans.
See: http://www.calacademy.org/calwild/sum98/eye.htm

The HOME rolled the newt around in its beak constantly dipping it in
the water, swishing it back and forth occasional shaking the newt
violently. The HOME continued this activity for about ten minutes,
finally raising its head and swallowing the newt. The HOME was
observed constantly for the next 20 minutes with the expectation some
resulting ill effects. Finally the HOME regurgitated the newt and
repeated the same procedure as above including again swallowing the
newt. Continued observation of the HOME showed normal preening,
swmming and diving behavior.

This behavior raised several questions:

1. Are rough skinned newts a common dietary regime of the HOME?
2. Do other diving ducks feed on rough-skinned newts?
3. Was the rolling in a serrated beak and washing of the newt a
behavior of the HOME to remove the toxin from the newts poison glands?
4. Are HOME and other birds immune to tetrodotoxin?
5. How do they do that?

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