Red Crossbills & sunflowers

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Dave

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Aug 30, 2023, 11:09:57 AM8/30/23
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Richard Trinker just reported to eBird an observation of juvenile red crossbills at low elevation eating sunflower seed obtained from flowers at a public garden in Boulder. I had the same exact experience yesterday in two different yards on the east side of Fort Collins. The individuals I watched were young enough to have mostly straight beaks. Their vocalizations were a better way to quickly discern their not being house finches than their general appearance. Juveniles have also been at Grandview Cemetery in Fort Collins recently. It has been suggested this might indicate local, urban breeding. However, Richard’s and the Fort Collins observations suggest to me a widespread Front Range shift of young birds to low elevation of unknown duration to take advantage of an abundant, easy to obtain nutrition source.

The next issue of “Colorado Birds” has a “The Hungry Bird” article on crossbills foods OTHER THAN conifer seed but I didn’t say much about sunflower seed and juveniles because the literature doesn’t address it and I hadn’t personally seen it before yesterday.

Dave Leatherman
Fort Collins

Sent from my iPhone

Richard Trinkner

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Aug 30, 2023, 12:12:35 PM8/30/23
to Dave, Cobirds
Thanks, Dave, for the report about the crossbills in Fort Collins.

Your post got me wondering:

1. If juvenile crossbills are still developing curved beaks, might that explain why we don't see adults in these flocks feeding on sunflowers?  Could the juvenile beaks be more suited to prying seeds from the sunflowers than prying them from pine cones?  Or might adult beaks be less suited to sunflowers? (Although many of the juvies I saw yesterday had less curved beaks, several had very curved beaks, so maybe this theory doesn't work.)

2. Is there a shortage of food in the foothills for the juveniles?  There have long been sunflowers on the plains, but this is the first time I've seen crossbills encamped at the Community Gardens.  (They're still there, as of 6:45 this morning.)

3. Do juvenile crossbills generally separate from the adults and form juvenile flocks?

Here's a shot of one of the juvies yesterday.

Richard



Diana Beatty

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Aug 30, 2023, 12:27:35 PM8/30/23
to Richard Trinkner, Dave, Cobirds
In general, if breeding is successful in significant increases in the population and cone crops are small or depleted, Red Crossbills will erupt beyond usual ranges or habitats and pursue atypical food sources.  Red Crossbills tend to wander wherever the food is to be found and so may have less site fidelity than some other species.  I suspect the crossbills in the Boulder area had a successful breeding season and have well-enjoyed the local cone crops and now are dispersing due to their increased numbers to take advantage of a wider variety of foods. It has been noted that immature birds sometimes go through a teenager phase where they hang out together more than with the mature birds.  But the details about bill development and specific food sources is interesting!

Diana Beatty
El Paso County

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Chip Clouse

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Aug 30, 2023, 12:35:56 PM8/30/23
to Dave, CObirds
These posts remind me of when I moved from Boulder up to 8600 ft in North Beaver near Pinecliffe in 1996.  While I didn't actually move up until June 1st, the homeowner had me come up to housesit in either late April or early May.  They had a big kitchen window planter box that they filled with Black Oil Sunflower and 60-80 Red Crossbills were swarming that box.  These were adult birds of both sexes. When I actually moved up, the planter box was gone but I put up a bunch of feeders until a bear showed up a few weeks later.  I never again saw the spectacle of sunflower eating crossbills.

Good birding,
Chip Clouse
Lakewood

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Richard Trinkner

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Aug 30, 2023, 1:40:47 PM8/30/23
to Chip Clouse, Dave, CObirds
I just read the "Breeding" section about Red Crossbills in Cornell's Birds of the World.  I learned that Red Crossbills in North America potentially nest twice each year, once in the early spring and again in the late summer, depending upon the availability of cone seeds.

A hypothesis, based on my limited research: perhaps along the Front Range this year, crossbills nested in the early spring and produced the juvenile birds we are seeing now on sunflower seeds in Boulder and Fort Collins. The absence of adults in these flocks could be explained if the adults are currently nesting in the foothills in their second window of the year.

As a result, juveniles who hatched during the early spring are now separated from their parents -- hence the all-juvenile flocks in Boulder and Fort Collins.

Richard

Wayne and Robin Jasper

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Aug 30, 2023, 3:08:45 PM8/30/23
to Diana Beatty, Richard Trinkner, Dave, Cobirds
In Rocky Mountain National Park over the weekend I saw many immature Crossbills eating thistle seeds in two different locations, in case that is of interest. 

Robin Jasper
Larimer County
Sent from my iPhone


On Aug 30, 2023, at 10:27 AM, Diana Beatty <otowi...@gmail.com> wrote:


In general, if breeding is successful in significant increases in the population and cone crops are small or depleted, Red Crossbills will erupt beyond usual ranges or habitats and pursue atypical food sources.  Red Crossbills tend to wander wherever the food is to be found and so may have less site fidelity than some other species.  I suspect the crossbills in the Boulder area had a successful breeding season and have well-enjoyed the local cone crops and now are dispersing due to their increased numbers to take advantage of a wider variety of foods. It has been noted that immature birds sometimes go through a teenager phase where they hang out together more than with the mature birds.  But the details about bill development and specific food sources is interesting!

Diana Beatty
El Paso County

On Wed, Aug 30, 2023 at 10:12 AM 'Richard Trinkner' via Colorado Birds <cob...@googlegroups.com> wrote:
Thanks, Dave, for the report about the crossbills in Fort Collins.

Your post got me wondering:

1. If juvenile crossbills are still developing curved beaks, might that explain why we don't see adults in these flocks feeding on sunflowers?  Could the juvenile beaks be more suited to prying seeds from the sunflowers than prying them from pine cones?  Or might adult beaks be less suited to sunflowers? (Although many of the juvies I saw yesterday had less curved beaks, several had very curved beaks, so maybe this theory doesn't work.)

2. Is there a shortage of food in the foothills for the juveniles?  There have long been sunflowers on the plains, but this is the first time I've seen crossbills encamped at the Community Gardens.  (They're still there, as of 6:45 this morning.)

3. Do juvenile crossbills generally separate from the adults and form juvenile flocks?

Here's a shot of one of the juvies yesterday.

Richard

<2023-08-28_164052-RedCrossbill_BoulderCommunityGardens.jpg>


Steingraeber,David

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Aug 30, 2023, 9:14:58 PM8/30/23
to Dave, CObirds
Although I haven't observed crossbills feeding on sunflower heads (as Richard & Dave have), when they're in the ponderosa pines around our house west of Ft. Collins, they frequently feed on black oil sunflower fruits at our feeders.  Occasionally, they even visit a nyjer feeder, extending their tongues through the mesh to "lick up" the seeds (fruits, actually).

Dave Steingraeber
Larimer County west of Horsetooth Reservoir, 5760'
From: cob...@googlegroups.com <cob...@googlegroups.com> on behalf of Dave <daleat...@msn.com>
Sent: Wednesday, August 30, 2023 9:09 AM
To: CObirds <cob...@googlegroups.com>
Subject: [cobirds] Red Crossbills & sunflowers
 
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Cinnamon Bergeron

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Aug 31, 2023, 1:19:09 PM8/31/23
to Dave, CObirds
Regarding the Red Crossbills eating Sunflower seeds, my friend Lynda Ryan shared this on social media, as well. She witnessed young Red Crossbills feeding on Sunflower seeds at Rock Ledge Ranch in Colorado Springs. She was also very surprised. Here is a picture she took. 


Lynda is not part of this group, so I asked her permission to share this with you all. 

Cinnamon Bergeron 

On Wed, Aug 30, 2023 at 9:09 AM Dave <daleat...@msn.com> wrote:
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Mark Obmascik

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Aug 31, 2023, 1:48:23 PM8/31/23
to Dave, Cinnamon Bergeron, CObirds
Crossbills eat sunflower seed pretty much all winter at our feeders near Fraser in Grand County. 

Inline image
No feeders up in the summer because of bears.

Good birding.

Mark Obmascik
Fraser, CO

DAVID A LEATHERMAN

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Aug 31, 2023, 4:45:32 PM8/31/23
to Diana Beatty, Richard Trinkner, Cobirds

This crossbill-sunflower business is all very interesting.  Being true nomads, crossbills go wherever necessary to find food, be it conifer seeds or something else.  Summer is between last year’s mostly-depleted conifer seed crop and this year’s developing one, which is just now beginning to mature/be available.  Crossbills can raise multiple broods in a given year and can nest in any month.  Food sources, including cone crops and others, fluctuate wildly from year to year.  And while a crossed beak would seem to indicate specialized feeding, Dave and Carol Steingraeber’s experience of red crossbills obtaining nyger fruit (“seed”) from tiny openings via their tongue is informative.  Crossbills are amazingly clever, both in the way they utilize their unique beak and the ways they get around its limitations!  Put all these factors together and probably nothing they do should surprise us. 

 

My take is that, yes, it appears to have been a productive year for certain types of red crossbills.  Yes, juveniles seem to hang together.  Yes, perhaps their straight, barely curved, and/or newly crossed bills might make sunflower seed from flowers easier to obtain than conifer seed.  Yes, all the rain down low this year grew a TREMENDOUS crop of sunflowers.  Yes, still lots to observe, learn, and report.  I think I am hearing two types of red crossbills in urban Fort Collins (2s for sure, and maybe 4s?), both getting sunflower seed from flowers.  I know, I know, record them, edit the giant resultant files, create sonograms, get confirmation of the types.  I wish I knew how, which is nobody’s fault but my own.  Just haven’t paused to figure it all out for my clunky phone. Please tell me, which paper cup has the record button, or is it on the string?

 

The next “The Hungry Bird” article in the upcoming fall issue of “Colorado Birds” happens to be about what crossbills eat other than conifer seed.  Of course, the article was “in the can” before all this flurry of sunflower seed-eating we are witnessing.  The article gives this specific issue only minor mention.  Such is the nature of our business.  We should regret having only partial knowledge and revel in the opportunity to grow it.

 

Thanks for everyone who has shared their red crossbill sunflower experiences at feeders or at flowers.

 

Dave Leatherman

Fort Collins

Diana Beatty

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Aug 31, 2023, 4:59:54 PM8/31/23
to DAVID A LEATHERMAN, Richard Trinkner, Cobirds
As far as recording sounds from the phone, here is what I do, if that helps.

I personally use either Merlin or SongSleuth apps on my phone for bird sound recording.  SongSleuth was intended to work like Merlin before there was Merlin, but it is pretty terrible at sound ID.  However, it does make good quality sound recordings - at least on par with Merlin, and maybe a little better at picking up some things.

I then email the sound file to myself using the little sideways open triangle icon located somewhere near the file.  Then I go do the rest from a computer instead of the phone.

There are a lot of .wav file trimmer tools available for free, and some are simpler than others.  I think the last one I used was called Clideo.  Perhaps others can recommend the fastest, simplest online .wav file trimmer they've used?   

From my email I download the sound file to my desktop and then use the .wav file trimmer to cut it down to the desired area and save it with a new name back on my desktop (which preserves the original in case I want to trim down to some other section as well).  

Finally, I upload the trimmed file to my eBird checklist the same way photos are uploaded there.

I hope that helps someone!

Diana Beatty
El Paso County


Terri Kurtz

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Sep 1, 2023, 3:10:23 PM9/1/23
to DAVID A LEATHERMAN, Diana Beatty, Richard Trinkner, Cobirds
I have also visited the crossbills this year at the Boulder community gardens (thanks Richard).  From your comment, David, on the use of tongues, thought you would enjoy this capture…using both tongue and beak to pull out the seed. Impressive to watch them shuck the seed from the shell also.
image0.jpeg
 Terri Kurtz
Boulder 


 

On Aug 31, 2023, at 2:45 PM, DAVID A LEATHERMAN <daleat...@msn.com> wrote:



This crossbill-sunflower business is all very interesting.  Being true nomads, crossbills go wherever necessary to find food, be it conifer seeds or something else.  Summer is between last year’s mostly-depleted conifer seed crop and this year’s developing one, which is just now beginning to mature/be available.  Crossbills can raise multiple broods in a given year and can nest in any month.  Food sources, including cone crops and others, fluctuate wildly from year to year.  And while a crossed beak would seem to indicate specialized feeding, Dave and Carol Steingraeber’s experience of red crossbills obtaining nyger fruit (“seed”) from tiny openings via their tongue is informative.  Crossbills are amazingly clever, both in the way they utilize their unique beak and the ways they get around its limitations!  Put all these factors together and probably nothing they do should surprise us. 

 

My take is that, yes, it appears to have been a productive year for certain types of red crossbills.  Yes, juveniles seem to hang together.  Yes, perhaps their straight, barely curved, and/or newly crossed bills might make sunflower seed from flowers easier to obtain than conifer seed.  Yes, all the rain down low this year grew a TREMENDOUS crop of sunflowers.  Yes, still lots to observe, learn, and report.  I think I am hearing two types of red crossbills in urban Fort Collins (2s for sure, and maybe 4s?), both getting sunflower seed from flowers.  I know, I know, record them, edit the giant resultant files, create sonograms, get confirmation of the types.  I wish I knew how, which is nobody’s fault but my own.  Just haven’t paused to figure it all out for my clunky phone. Please tell me, which paper cup has the record button, or is it on the string?

 

The next “The Hungry Bird” article in the upcoming fall issue of “Colorado Birds” happens to be about what crossbills eat other than conifer seed.  Of course, the article was “in the can” before all this flurry of sunflower seed-eating we are witnessing.  The article gives this specific issue only minor mention.  Such is the nature of our business.  We should regret having only partial knowledge and revel in the opportunity to grow it.

 

Thanks for everyone who has shared their red crossbill sunflower experiences at feeders or at flowers.

 

Dave Leatherman

Fort Collins

 

From: Diana Beatty <otowi...@gmail.com>
Sent: Wednesday, August 30, 2023 10:27 AM
To: Richard Trinkner <rtri...@icloud.com>
Cc: Dave <daleat...@msn.com>; Cobirds <cob...@googlegroups.com>
Subject: Re: [cobirds] Red Crossbills & sunflowers

 

In general, if breeding is successful in significant increases in the population and cone crops are small or depleted, Red Crossbills will erupt beyond usual ranges or habitats and pursue atypical food sources.  Red Crossbills tend to wander wherever the food is to be found and so may have less site fidelity than some other species.  I suspect the crossbills in the Boulder area had a successful breeding season and have well-enjoyed the local cone crops and now are dispersing due to their increased numbers to take advantage of a wider variety of foods. It has been noted that immature birds sometimes go through a teenager phase where they hang out together more than with the mature birds.  But the details about bill development and specific food sources is interesting!

 

Diana Beatty

El Paso County

 

On Wed, Aug 30, 2023 at 10:12 AM 'Richard Trinkner' via Colorado Birds <cob...@googlegroups.com> wrote:

Thanks, Dave, for the report about the crossbills in Fort Collins.

 

Your post got me wondering:

 

1. If juvenile crossbills are still developing curved beaks, might that explain why we don't see adults in these flocks feeding on sunflowers?  Could the juvenile beaks be more suited to prying seeds from the sunflowers than prying them from pine cones?  Or might adult beaks be less suited to sunflowers? (Although many of the juvies I saw yesterday had less curved beaks, several had very curved beaks, so maybe this theory doesn't work.)

 

2. Is there a shortage of food in the foothills for the juveniles?  There have long been sunflowers on the plains, but this is the first time I've seen crossbills encamped at the Community Gardens.  (They're still there, as of 6:45 this morning.)

 

3. Do juvenile crossbills generally separate from the adults and form juvenile flocks?

 

Here's a shot of one of the juvies yesterday.

 

Richard

 

<image001.jpg>

 

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