Mike and Tweeters,

Climbing nightshade, or bittersweet nightshade (Solanum dulcamara)
is a widespread weed in Washington, and as you point out, its toxic
properties are well-known.

However, the highest concentration of the toxic alkaloids are in the
green (immature) fruits. The ripe fruits, which are orange-red in color
(like miniature tomatoes) have little or none of the toxic chemicals.

In addition, at least one source that I consulted claimed that
the plant is not poisonous to birds, although the immature fruits
are known to be extremely toxic to humans, sheep, and rodents,
at the least.

One should not assume, because a given plant is poisonous to humans
and other mammals, that it is poisonous to birds. For example, poison
ivy and poison oak berries, while poisonous to humans, are not toxic
to birds and are eaten by numerous bird species. On the other hand,
avocados, which are quite edible to humans, can be deadly to some birds.
I have heard of pet parrots being killed after being fed avocado by their
owner, who was unaware of their poisonous properties.

So it may well be that sparrows and other birds can eat and digest
nightshade berries with no harm at all.

Wayne C. Weber
Delta, BC
contopus at telus.net



----- Original Message -----
From: "mike denny" <m.denny at charter.net>
To: "AMY DAVID SHUMANN" <daccshumann at msn.com>; <tweeters at u.washington.edu>
Sent: Friday, December 08, 2006 6:56 PM
Subject: Re: [Tweeters] birds and toxic berries


Hello All,

On 7 November 2004 while birding with John Gatchet below McNary
Dam on the Columbia River. We watched as two tan-striped
White-throated Sparrows fed on the beautiful eye catching red-orange
fruits/berries of the Climbing Nightshade (Solanum dulcamara). These
sparrows fed on 5-7 berries each, smashing the soft red flesh and
consuming the seeds with seeming impunity.

This plant and all of its parts are poison and contain compounds such as
solanine, glycoside,dulcamarine to name a few. So we marveled at
how these two small bodied birds could ingest these toxins and then
fly off unaffected? See Oregon Birds 31(3):117.

Later Mike

********************************************************************
Mike & MerryLynn Denny
1354 S. E. Central Ave.
College Place, WA 99324
509.529.0080 (h)

IF YOU HAVEN'T BEEN BIRDING, YOU HAVEN'T LIVED!
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