Date: 7/21/26 1:17 pm From: ed pandolfino via groups.io <erpfromca...> Subject: Re: [centralvalleybirds] Two California BBA suggestions
In my earlier post about White-breasted Nuthatch subspecies, I should have mentioned that eBird includes S. c. tenuissima within the "Interior West" subspecies group.
Ed PandolfinoSacramento
On Monday, July 20, 2026 at 05:52:09 PM PDT, ed pandolfino via groups.io <erpfromca...> wrote:
For those of us participating in the California Breeding Bird Atlas (https://www.californiabirdatlas.org/) the following suggestions can help improve the data quality for the Atlas.
1. Continueadding breeding codes (esp. confirmatory ones) even after a species hasbeen confirmed in a block. In addition to providing breeding distribution data,Breeding Bird Atlases are a great source of phenology data (timing of breedingbehaviors). In a rapidly changing climate, capturing this sort of data mayprove even more valuable than distribution data. So please continue to addcodes throughout the life of the Atlas.
2. White-breastedNuthatch subspecies: When diagnostic vocalizations are heard, please assignbreeding codes to the subspecies of White-breasted Nuthatch. This taxon maywell be split and the subspecies found in the western portions of state (S.c. aculeata) will be a separate species from the eastern subspecies (S.c. tenuissima). You can read about their distribution in California here (https://doi.org/10.21199/WB48.1.2),and listen to the diagnostic vocalization here (aculeata typical song https://xeno-canto.org/1094766;aculeata call https://xeno-canto.org/468235; tenuissima calls https://xeno-canto.org/443282andhttps://xeno-canto.org/1153733).
Ed PandolfinoSacramento
Date: 7/20/26 9:01 pm From: Andrew Engilis, Jr. via groups.io <aengilis...> Subject: [centralvalleybirds] Spotted Owl Records from Central Valley
Hi all, I am working on a paper synthesizing records of Spotted Owl from the Central Valley floor. I have run across possible records from Merced County and Fresno County, but there are no details. Does anyone know the provenance of those records and what type of documentation there might be?
Date: 7/20/26 5:52 pm From: ed pandolfino via groups.io <erpfromca...> Subject: [centralvalleybirds] Two California BBA suggestions
For those of us participating in the California Breeding Bird Atlas (https://www.californiabirdatlas.org/) the following suggestions can help improve the data quality for the Atlas.
1. Continueadding breeding codes (esp. confirmatory ones) even after a species hasbeen confirmed in a block. In addition to providing breeding distribution data,Breeding Bird Atlases are a great source of phenology data (timing of breedingbehaviors). In a rapidly changing climate, capturing this sort of data mayprove even more valuable than distribution data. So please continue to addcodes throughout the life of the Atlas.
2. White-breastedNuthatch subspecies: When diagnostic vocalizations are heard, please assignbreeding codes to the subspecies of White-breasted Nuthatch. This taxon maywell be split and the subspecies found in the western portions of state (S.c. aculeata) will be a separate species from the eastern subspecies (S.c. tenuissima). You can read about their distribution in California here (https://doi.org/10.21199/WB48.1.2),and listen to the diagnostic vocalization here (aculeata typical song https://xeno-canto.org/1094766;aculeata call https://xeno-canto.org/468235; tenuissima calls https://xeno-canto.org/443282andhttps://xeno-canto.org/1153733).
Ed PandolfinoSacramento
Date: 7/6/26 12:17 pm From: ed pandolfino via groups.io <erpfromca...> Subject: Re: [centralvalleybirds] Purple martins in the Valley again?
And another, potentially important difference between western and eastern Purple Martins is their non-breeding range. Though the sample size is small, a geolocator study in 2012 (Fraser et al. 2012. Proc. RoyalSoc. B. 279:4901) showed that eastern martins wintered mainly in the Amazon Basin, where most of the habitat is intact, while the western birds they tagged wintered in the Atlantic Coastal Rain Forests in eastern Brazil, where the habitat is now present only in isolated fragments (mainly due to enormous sugar cane plantations).
Ed PandolfinoSacramento, CA
On Monday, July 6, 2026 at 11:58:40 AM PDT, Dan Airola via groups.io <d.airola...> wrote:
Useful summary of the genetics study by Alan Baker, Alvaro. Genetic work on the whole North American population is underway now, being conducted by PhD student Victoria Wiley at Columbia University. She presented a brief progress report on her work to the California Purple Martin Working Group last month. I don’t want to try to summarize it for fear of getting it wrong, but my impression was that it largely confirmed the current subspecies separations but showed some separation between Western martins between the Pacific Coast and the Rockies and interior mountain ranges (which Baker was working on, but died before he published).
If anyone is interested in joining the working group, PM me. We meet 2-3 times/yr via zoom
Dan AirolaConservation Research and <Planningd.airola...>/494-1283
On Jul 6, 2026, at 11:39 AM, Alvaro Jaramillo via groups.io <chucao...> wrote:
All
A perspective of the importance of Western Purple Martins. There was a paper done some time ago now (2007) that showed the genetic distinctness of the Western Purple Martins vs the Eastern birds. Note that they did not sample the desert nesting population from US/Mexico. This study having been done a while ago is much less informative than the type of genetic work that can be done today (genomics), it was restricted to mitochondrial DNA which has plusses and minuses. It would be superb to have a modern genetic study, and also include the desert birds as well as perhaps the entire Progne (large martins) genus, with multiple populations sampled. The study suggested that the split might have happened 400,000 years ago between eastern and western. There was some evidence of some eastern genes in British Columbia birds. Yet, not a lot from what I could read. Cutting to the punch line here, martins of different species are quite similar, some nearly impossible to separate in some plumages (usually the adult male plumage). The fact that eastern and western Purple are similar looking (females are separable though), is not unusual in this group. But knowing that they are well separated genetically is intriguing. With further work they may prove to be different species, at least the published data so far does not exclude this possibility. If so, the importance of conservation of the Western Purple Martins becomes even greater as they are perhaps more unique than have been given credit for.
Alvaro
Alvaro Jaramillo
<alvaro...>
www.alvarosadventures.com
From: <centralvalleybirds...> <centralvalleybirds...> On Behalf Of Steve Hampton via groups.io
Sent: Friday, July 3, 2026 9:12 AM
To: <centralvalleybirds...>
Subject: Re: [centralvalleybirds] Purple martins in the Valley again?
I'll add a few more observations from the Pacific Northwest.
- There are lots of Purple Martins but they are largely limited to using artificial nest boxes over or very near (within 20 yards) the water (e.g. at marinas). They are very rare in natural contexts.
- Build it and they will come - when new boxes are installed, they are often fully occupied within one or two years, implying that there is a shortage of suitable breeding cavities and many floaters in the population. This is not surprising, as waterfront homeowners and land mgrs (e.g. local parks, etc.) readily remove snags. Most of the waterfront areas are manicured to some degree.
- Starlings aren't a huge problem here. Because the starlings nest earlier, they are typically feeding young by May 1, when the martins arrive. At our nest box arrays, we either don't install them or we keep doors over the entrances until May 1. However, even it we neglect to do that, starlings are not necessarily a problem (at least in more rural areas). Some of our nest box arrays are installed and managed by older volunteers who do not manage to pass on mgmt to others before they become unable to care for the boxes. Thus, quite a few nest box arrays are abandoned by their human caretakers. At these, starlings typically occupy only one or two boxes out of six to fifteen present, with the martins in the rest. Perhaps in more urban areas, where there are more starlings, this could be a problem -- though it is easier to find people to oversee the boxes there.
- If nest box arrays are put up too far from the water, the martins aren't interested in them and the boxes may be used by House Sparrows and/or starlings.
- Kestrels and merlins (we have local nesting black merlins here) are not too much of a problem either. A colony of 6 pairs of martins seems to be sufficient for them to gang up and attack and chase away a merlin (yes - I've witnessed that).
- Because neonic pesticides are largely confined to commercial ag (with most use in the Corn Belt and in Calif's Central Valley), it does not seem we have that problem here, though it is difficult to tell. For more on how neonics are wiping out even American Robins and Red-winged Blackbirds in the Corn Belt, see eBird trend maps, which I summarize at my Substack post here: Silence in the Corn Belt.
I'm not sure if any of this is helpful for the Central Valley.
On Thu, Jul 2, 2026 at 10:42 PM Dan Airola via groups.io <d.airola...> wrote:
Translocation won’t solve the underlying problem of lack of sufficient insect populations. It could also mess up the genetics. Permits would be required and almost surely wouldn’t be granted.
Populations, although local, appear to be pretty healthy in the coastal forest region (Marin north to Del Norte county).
The real solution seems to be to further restrict neonicotinoid pesticides and let the prey base recover, and the martins will follow. Remember that Sacramento had the largest colonies in western North America in the early 2000s, decades after starlings were established as breeders there. If we don’t lose the tenuous source population and bring the insects back, it could happen again. But starling competition would still be a problem in rural areas that support more starlings. There it will take a gradual expansion to starling proof nest boxes from the few source populations, a multi-decade proposition
Well that’s probably enough about martins for the next year or so!
Dan Airola
Conservation Research and Planning
<d.airola...>
916/494-1283
On Jul 2, 2026, at 7:20 PM, Larry Montgomery via groups.io <telemark22...> wrote:
If Puget Sound is the closest healthy population, do you assume capture and reintroduction would be necessary? Otherwise, I would think it would be good to have similar safe spaces constructed continuously down through Oregon and Northern CA. That would be worthwhile, but a very slow way to bring them back, which is, indeed, a worthy goal.
Larry Montgomery
Sacramento (but sweltering in Maine at the moment)
Date: 7/6/26 11:39 am From: Alvaro Jaramillo via groups.io <chucao...> Subject: Re: [centralvalleybirds] Purple martins in the Valley again?
All
A perspective of the importance of Western Purple Martins. There was a paper done some time ago now (2007) that showed the genetic distinctness of the Western Purple Martins vs the Eastern birds. Note that they did not sample the desert nesting population from US/Mexico. This study having been done a while ago is much less informative than the type of genetic work that can be done today (genomics), it was restricted to mitochondrial DNA which has plusses and minuses. It would be superb to have a modern genetic study, and also include the desert birds as well as perhaps the entire Progne (large martins) genus, with multiple populations sampled. The study suggested that the split might have happened 400,000 years ago between eastern and western. There was some evidence of some eastern genes in British Columbia birds. Yet, not a lot from what I could read. Cutting to the punch line here, martins of different species are quite similar, some nearly impossible to separate in some plumages (usually the adult male plumage). The fact that eastern and western Purple are similar looking (females are separable though), is not unusual in this group. But knowing that they are well separated genetically is intriguing. With further work they may prove to be different species, at least the published data so far does not exclude this possibility. If so, the importance of conservation of the Western Purple Martins becomes even greater as they are perhaps more unique than have been given credit for.
From: <centralvalleybirds...> <centralvalleybirds...> On Behalf Of Steve Hampton via groups.io
Sent: Friday, July 3, 2026 9:12 AM
To: <centralvalleybirds...>
Subject: Re: [centralvalleybirds] Purple martins in the Valley again?
I'll add a few more observations from the Pacific Northwest.
* There are lots of Purple Martins but they are largely limited to using artificial nest boxes over or very near (within 20 yards) the water (e.g. at marinas). They are very rare in natural contexts.
* Build it and they will come - when new boxes are installed, they are often fully occupied within one or two years, implying that there is a shortage of suitable breeding cavities and many floaters in the population. This is not surprising, as waterfront homeowners and land mgrs (e.g. local parks, etc.) readily remove snags. Most of the waterfront areas are manicured to some degree.
* Starlings aren't a huge problem here. Because the starlings nest earlier, they are typically feeding young by May 1, when the martins arrive. At our nest box arrays, we either don't install them or we keep doors over the entrances until May 1. However, even it we neglect to do that, starlings are not necessarily a problem (at least in more rural areas). Some of our nest box arrays are installed and managed by older volunteers who do not manage to pass on mgmt to others before they become unable to care for the boxes. Thus, quite a few nest box arrays are abandoned by their human caretakers. At these, starlings typically occupy only one or two boxes out of six to fifteen present, with the martins in the rest. Perhaps in more urban areas, where there are more starlings, this could be a problem -- though it is easier to find people to oversee the boxes there.
* If nest box arrays are put up too far from the water, the martins aren't interested in them and the boxes may be used by House Sparrows and/or starlings.
* Kestrels and merlins (we have local nesting black merlins here) are not too much of a problem either. A colony of 6 pairs of martins seems to be sufficient for them to gang up and attack and chase away a merlin (yes - I've witnessed that).
* Because neonic pesticides are largely confined to commercial ag (with most use in the Corn Belt and in Calif's Central Valley), it does not seem we have that problem here, though it is difficult to tell. For more on how neonics are wiping out even American Robins and Red-winged Blackbirds in the Corn Belt, see eBird trend maps, which I summarize at my Substack post here: Silence in the Corn Belt <https://substack.com/@schampton/p-192908892> .
I'm not sure if any of this is helpful for the Central Valley.
Translocation won’t solve the underlying problem of lack of sufficient insect populations. It could also mess up the genetics. Permits would be required and almost surely wouldn’t be granted.
Populations, although local, appear to be pretty healthy in the coastal forest region (Marin north to Del Norte county).
The real solution seems to be to further restrict neonicotinoid pesticides and let the prey base recover, and the martins will follow. Remember that Sacramento had the largest colonies in western North America in the early 2000s, decades after starlings were established as breeders there. If we don’t lose the tenuous source population and bring the insects back, it could happen again. But starling competition would still be a problem in rural areas that support more starlings. There it will take a gradual expansion to starling proof nest boxes from the few source populations, a multi-decade proposition
Well that’s probably enough about martins for the next year or so!
If Puget Sound is the closest healthy population, do you assume capture and reintroduction would be necessary? Otherwise, I would think it would be good to have similar safe spaces constructed continuously down through Oregon and Northern CA. That would be worthwhile, but a very slow way to bring them back, which is, indeed, a worthy goal.
Larry Montgomery
Sacramento (but sweltering in Maine at the moment)
Date: 7/5/26 9:48 pm From: Michael Perrone via groups.io <michaelperrone10...> Subject: [centralvalleybirds] purple martins in the Valley again--NOT LIKELY
Thanks to everyone who responded to my July 1 suggestion about resurrecting martin nesting in the valley by putting nest boxes over water. You experts noted that (1) nest sites are not in short supply--martins have loads of potential nest sites here that starlings don't use, on the undersides of highway bridges, so there is little reason to think they'd use nest boxes instead; (2) martins are colonial and thus very unlikely to use a new box without other martins already at the site; and (3) there are scarcely enough surplus or floater martins anywhere in this valley to found a new colony. Well, darn it.
You offered lots of other helpful information and insight as well. Thanks so much,
Michael perroneDavis CA
Date: 7/3/26 6:12 am From: Steve Hampton via groups.io <stevechampton...> Subject: Re: [centralvalleybirds] Purple martins in the Valley again?
I'll add a few more observations from the Pacific Northwest.
- There are lots of Purple Martins but they are largely limited to using
artificial nest boxes over or very near (within 20 yards) the water (e.g.
at marinas). They are very rare in natural contexts.
- Build it and they will come - when new boxes are installed, they are
often fully occupied within one or two years, implying that there is a
shortage of suitable breeding cavities and many floaters in the population.
This is not surprising, as waterfront homeowners and land mgrs (e.g. local
parks, etc.) readily remove snags. Most of the waterfront areas are
manicured to some degree.
- Starlings aren't a huge problem here. Because the starlings nest
earlier, they are typically feeding young by May 1, when the martins
arrive. At our nest box arrays, we either don't install them or we keep
doors over the entrances until May 1. However, even it we neglect to do
that, starlings are not necessarily a problem (at least in more rural
areas). Some of our nest box arrays are installed and managed by older
volunteers who do not manage to pass on mgmt to others before they become
unable to care for the boxes. Thus, quite a few nest box arrays are
abandoned by their human caretakers. At these, starlings typically occupy
only one or two boxes out of six to fifteen present, with the martins in
the rest. Perhaps in more urban areas, where there are more starlings, this
could be a problem -- though it is easier to find people to oversee the
boxes there.
- If nest box arrays are put up too far from the water, the martins
aren't interested in them and the boxes may be used by House Sparrows
and/or starlings.
- Kestrels and merlins (we have local nesting black merlins here) are
not too much of a problem either. A colony of 6 pairs of martins seems to
be sufficient for them to gang up and attack and chase away a merlin (yes -
I've witnessed that).
- Because neonic pesticides are largely confined to commercial ag (with
most use in the Corn Belt and in Calif's Central Valley), it does not seem
we have that problem here, though it is difficult to tell. For more on how
neonics are wiping out even American Robins and Red-winged Blackbirds in
the Corn Belt, see eBird trend maps, which I summarize at my Substack post
here: *Silence in the Corn Belt
<https://substack.com/@schampton/p-192908892>*.
I'm not sure if any of this is helpful for the Central Valley.
On Thu, Jul 2, 2026 at 10:42 PM Dan Airola via groups.io <d.airola=
<sbcglobal.net...> wrote:
> Translocation won’t solve the underlying problem of lack of sufficient
> insect populations. It could also mess up the genetics. Permits would be
> required and almost surely wouldn’t be granted.
>
> Populations, although local, appear to be pretty healthy in the coastal
> forest region (Marin north to Del Norte county).
>
> The real solution seems to be to further restrict neonicotinoid pesticides
> and let the prey base recover, and the martins will follow. Remember that
> Sacramento had the largest colonies in western North America in the early
> 2000s, decades after starlings were established as breeders there. If we
> don’t lose the tenuous source population and bring the insects back, it
> could happen again. But starling competition would still be a problem in
> rural areas that support more starlings. There it will take a gradual
> expansion to starling proof nest boxes from the few source populations, a
> multi-decade proposition
>
> Well that’s probably enough about martins for the next year or so!
>
> Dan Airola
> Conservation Research and Planning
> <d.airola...>
> 916/494-1283
>
>
> On Jul 2, 2026, at 7:20 PM, Larry Montgomery via groups.io <telemark22=
> <sbcglobal.net...> wrote:
>
>
> If Puget Sound is the closest healthy population, do you assume capture
> and reintroduction would be necessary? Otherwise, I would think it would
> be good to have similar safe spaces constructed continuously down through
> Oregon and Northern CA. That would be worthwhile, but a very slow way to
> bring them back, which is, indeed, a worthy goal.
> Larry Montgomery
> Sacramento (but sweltering in Maine at the moment)
>
>
>
>
Date: 7/2/26 9:13 pm From: Greg Haworth via groups.io <g.haworth...> Subject: Re: [centralvalleybirds] Purple martins in the Valley again?
For what it's worth, Purple Martins have a very healthy population on
Suavie Island just outside of Portland.
They nest in the dead trees in the cotton wood gallery tracts. And the
ODFW has multiple Martin gourd arrays around the island as well.
Greg Haworth
Portland Oregon
On Thu, Jul 2, 2026, 7:20 PM Larry Montgomery via groups.io <telemark22=
<sbcglobal.net...> wrote:
> If Puget Sound is the closest healthy population, do you assume capture
> and reintroduction would be necessary? Otherwise, I would think it would
> be good to have similar safe spaces constructed continuously down through
> Oregon and Northern CA. That would be worthwhile, but a very slow way to
> bring them back, which is, indeed, a worthy goal.
> Larry Montgomery
> Sacramento (but sweltering in Maine at the moment)
>
>
>
Date: 7/2/26 7:20 pm From: Larry Montgomery via groups.io <telemark22...> Subject: Re: [centralvalleybirds] Purple martins in the Valley again?
If Puget Sound is the closest healthy population, do you assume capture and reintroduction would be necessary? Otherwise, I would think it would be good to have similar safe spaces constructed continuously down through Oregon and Northern CA. That would be worthwhile, but a very slow way to bring them back, which is, indeed, a worthy goal.Larry MontgomerySacramento (but sweltering in Maine at the moment)
Date: 7/1/26 11:20 am From: Michael Perrone via groups.io <michaelperrone10...> Subject: [centralvalleybirds] Purple martins in the Valley again?
Some sixty years ago, starlings colonized the valley and captured nearly all the desirable nest cavities, prompting (I think) the steep decline of martins. Despite the starlings, martins remain as breeders elsewhere, including around Puget Sound. There martins use nest boxes placed on poles over water, typically on the ends of piers and boat ramps. In my experience, starlings don't use those boxes. It seems that starlings don't nest over water.
So, I suggest that we place boxes in such situations here, and see what happens. With their boating facilities, the Sacamento River and big water reservoirs seem good candidates. Can we give it a try? Eagle Scout project, anyone?
Please let me know what you think.
Michael PerroneDavis
