Date: 6/30/26 8:44 pm From: Robert O'Brien via Tweeters <tweeters...> Subject: Re: [Tweeters] evening grosbeaks in urgent trouble on hwy 20
Sounds terrible. Other than contacting some authority who prefers not to
be contacted, I guess the best thing to do is to document it thoroughly in
hopes of future remediation.. I queried Chat GPT, which confirmed your
analysis. Here is the response. There were photos supporting what you
report,, which I've had to delete because Tweeters don't accept them. Bob
OBrien Portland
ChatGPT response.
Yes. In fact, as I read the message, several details immediately rang a
bell. This is *not a new phenomenon*, although it does appear to be
unusually severe in some years.
The key point is that the explanation given—*road salt attracting Evening
Grosbeaks*—is considered the leading explanation by many ornithologists and
transportation biologists. It isn't just internet speculation.
Several independent sources document this:
- Evening Grosbeaks, along with Pine Siskin, Red Crossbill, and other
finches, are well known to congregate on salted roads where they
pick up *salt
and small gravel (grit)* needed for digestion.
- Birds feeding on roads often become surprisingly reluctant to flush
and can appear almost tame or lethargic, leading to heavy mortality from
vehicles. Transportation researchers have even proposed studies to
determine whether excessive sodium itself contributes to this behavior.
- One documented case in British Columbia reported *at least 2,000
Evening Grosbeaks killed along only 16 km of highway*.
The interesting part is that *Kelly McAllister of the Washington State
Department of Transportation* actually proposed research on exactly this
issue over a decade ago. The proposal notes that finches are periodically
drawn to salted roads, where many are crushed by vehicles, and that
transportation agencies need better information to develop mitigation
strategies.
Why this year?
That's the million-dollar question.
Several things probably have to line up:
- A large local concentration of Evening Grosbeaks.
- Late snow or limited natural mineral sources.
- Fresh salt remaining on the pavement after winter.
- Dry pavement that makes the salt easy to find.
- The birds' seasonal need for grit and minerals.
These "perfect storm" years may occur only occasionally, which explains why
someone could drive SR-20 for years without seeing anything like this.
Is road salt definitely the culprit?
Probably—but with an important qualification.
The birds are likely attracted to *both*:
- sodium salts, and
- grit (small stones) that they swallow to grind seeds in the gizzard.
Those two often occur together on mountain highways.
What can actually be done?
Simply banning road salt isn't necessarily practical. SR-20 crosses high
mountain passes, and road salt can greatly reduce serious accidents.
More realistic mitigation measures might include:
- sweeping residual salt and grit from shoulders after snow season,
- using alternative de-icers where feasible,
- identifying recurring "hot spots,"
- temporary warning signs during peak mortality,
- reduced speed limits through affected stretches,
- research into whether different de-icing materials reduce bird
attraction.
Transportation biologists have been discussing these possibilities for
years, but there is still surprisingly little hard research.
One thing that caught my attention
The writer says:
"dead birds every few feet"
If that is literally true over many miles, that represents *an
exceptionally large mortality event*, even by the standards of previous
reports. I would hope the state wildlife agency documents it.
Given your birding background, I'd also be interested in one more
question: *Were
they really all Evening Grosbeaks?* Large flocks of finches can include Pine
Siskin, Red Crossbill, and Cassin's Finch in the Cascades. An actual survey
of the carcasses would tell us whether one species is disproportionately
affected.
This is exactly the sort of event that organizations such as the Washington
Department of Fish and Wildlife and the Cornell Lab of Ornithology would
likely want documented if it is occurring on the scale described.
On Tue, Jun 30, 2026 at 7:45 PM via Tweeters <tweeters...>
wrote:
>
>
> Hi Tweeters,
>
>
>
> I drove to the north cascades on Saturday for a hike, and I saw an
> absolute horror.
>
>
>
> *Something absolutely horrible is happening right now on the North
> Cascades highway (SR-20). Definitely hundreds, if not thousands of little
> birds are getting murdered. Right after the highway starts to climb up
> after the Diablo reservoir and reaches the sub-alpine areas until it goes
> back down after the Washington pass, these little birds are attracted to
> the road for some reason. Flocks of birds are sitting on the median line,
> rumble strips and sides. There are many birds and they are just getting
> plowed through by the car drivers. I have never seen something so horrible
> before. There are dead birds on the road every few feet. Literally. I have
> also never seen birds being so attracted to the roadway before either. I
> drove this stretch of the highway at 15mph for an hour and made several
> other drivers mad (their problem!), and I didn’t hit any birds, but it is
> just horrible carnage out there regardless.* *Looking online, I found out
> the birds are called evening grosbeaks and several people think that most
> likely birds are on the road because they are attracted to the road salt.
> If that is true, at least we can do something to save them. Why is WSDOT
> still using road salt? Who can we complain to ban road salt??? This is
> unacceptable.*
>
> *I see many other people reported the same situation online, looks like
> evening grosbeaks are getting killed by thousands since Hwy opened.*
>
>
>
> 1. *I have already messaged WSDOT on their social media, but they
> didn’t respond.*
> 2. *Is the guess even correct, and the birds are attracted to the
> salt? If so, why I have not seen this problem in years past.*
> 3. *Most important: what can we do to help the birds?*
>
>
>
> *Nikita*
>
>
>
>
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