Date: 11/12/25 3:06 pm From: richard cimino via groups.io <yellowbilledtours...> Subject: Re: [northbaybirds] Outer Point Reyes 11/10/25 - Tricolored Blackbirds
Dominik,
The California Audubon web site states that Ag. Field primarily grain fields are the habitat of choice for nesting for TRBL. The Marin County Breeding Altas is in its editing stage; it would be interesting to learn if the Point Reyes blocks will have TRBL nesting confirmation.
Audubon California web site detailing their TRBL conservation efforts:
“As marshlands and native foraging areas disappeared along the coast and in the Central Valley, Tricolored Blackbirds became increasingly dependent on agricultural fields, primarily grain fields, for nesting. This puts colonies at risk, as farmers often need to harvest crops before chicks have fledged”.
Rich Cimino
Larkspur
From: <northbaybirds...> <northbaybirds...> On Behalf Of Dominik Mosur via groups.io
Sent: Wednesday, November 12, 2025 11:30 AM
To: <northbaybirds...>
Subject: Re: [northbaybirds] Outer Point Reyes 11/10/25 - ROUGH-LEGGED HAWKS et al.
Jeff, thank you for the added comments on Tricolored blackbirds. I should have been more detailed in my statements . In essence I am wondering how the Tricolored Population in Point Reyes will be affected by the end of cattle grazing and glad to hear that other habitat management will be employed.
Oh wait never mind- I see that you cc’d the list.
And yes I’ll be doing Hall Ranch this year and hope to see you at the count down.
I should have been more detailed in my statements. Obviously trikes did not evolve with industrial grazing, the point I was trying to make is that essentially all appropriate habitat for them in the state is dedicated to this use and was wondering how the change will affect the Point Reyes population going forward.
d
On Nov 12, 2025, at 11:23, Jeff Miller <jmiller...> <mailto:<jmiller...> > wrote:
Yes, please do!
I hope to run into you birding sometime – are you doing the Point Reyes CBC?
Jeff
From: <dominikmosur...> <mailto:<dominikmosur...> <dominikmosur...> <mailto:<dominikmosur...> >
Sent: Wednesday, November 12, 2025 11:22 AM
To: Jeff Miller <jmiller...> <mailto:<jmiller...> >
Subject: Re: [northbaybirds] Outer Point Reyes 11/10/25 - ROUGH-LEGGED HAWKS et al.
Hi Jeff,
Thank you. Can I repost your information in this email as an addendum to my report?
d
On Nov 12, 2025, at 11:07, Jeff Miller <jmiller...> <mailto:<jmiller...> > wrote:
Thanks for the rare birds report, Dominik.
I want to point out that winter foraging tricolored blackbirds are not necessarily dependent upon cattle ranches, though grain and silage at ranches is now the easiest food source for tricoloreds. Obviously tricoloreds did not evolve with cattle ranching since
ranching didn't begin in California until the late 1700s, 250 years ago, while tricolored blackbirds are thought to have diverged from red-winged blackbirds about 10,000 years ago. Yes, due to the loss of most of their natural foraging habitats in California (native wetlands and upland habitats which have been destroyed or altered), tricoloreds are now highly dependent for foraging on semi-natural grasslands and artificial habitats like agricultural fields and croplands, as well as dairies and feedlots. Ideal foraging conditions for this species is not necessarily cattle ranches, but rather short grasslands. Yes, that habitat condition is currently is created at Point Reyes by overgrazing, but it can also be produced by burning or seasonal mowing.
With the cessation of commercial ranching at Point Reyes, there will continue to be limited seasonal non-commercial grazing through a new restoration lease with The Nature Conservancy. TNC will be managing for native habitats and sensitive wildlife, likely using a variety of disturbance regimes, which will include some restricted cattle grazing, and could include burning and maybe seasonal mowing. There will be a public management plan for the former commercial ranch lease areas. The Park Service will also be co-managing with the Graton Rancheria, which wants to bring back cultural/ecological burning to Point Reyes. All of the conservation groups involved in the Point Reyes settlement and ranch retirements, TNC, the Park Service, and Graton are going to want to manage for sensitive species that like short grasslands, such as tricoloreds and burrowing owls. Birders should weigh in when the new management plan is being discussed.
Also important to note that the commercial (over)grazing that is being retired has had strongly negative impacts on other native rare birds like snowy plovers.
From: <northbaybirds...> <mailto:<northbaybirds...> <northbaybirds...> <mailto:<northbaybirds...> > On Behalf Of Dominik Mosur via groups.io
Sent: Wednesday, November 12, 2025 10:27 AM
To: North Bay Birds <northbaybirds...> <mailto:<northbaybirds...> >
Subject: [northbaybirds] Outer Point Reyes 11/10/25 - ROUGH-LEGGED HAWKS et al.
Taking advantage of the great weather I spent Monday, 11/10, hiking the pastures around the ranches on Outer Point Reyes.
Some bird species of note observed:
Snow Goose - lone bird flew in calling from Drakes Bay over the visitor centerin the morning, perhaps the continuing individual that has been seen with some regularity around the various ranches starting in early October this year
Lesser Scaup - a flock of 17 on the shallow Mendoza Ranch pond
Ring-necked Ducks - 7 on Spaletta and 3 on Mendoza ranch ponds
Long-billed Dowitcher - a juvenile was on the cattle pond near Drake's Corner. This bird flushed and flew off in the direction of the outer ranches and may have been the same individual noted on the Mendoza pond a few hours later
Bonaparte's Gull - Mendoza pond
Bald Eagle - adult flew in off Drake's Bay over the visitor center in the morning
ROUGH-LEGGED HAWKS - while walking the pastures of the Spaletta Ranch in the direction of Drake's Corner two juvenile Rough-legs flew over in quick succession heading toward the Lighthouse. About an hour later a juvenile Rough-legged hawk flew over the Hall Ranch/Drake's Corner heading north. Later a juvenile Rough-leg was observed over the pastures of the Nunes Ranch. I suspect the later two observations were of the first two birds moving around. It has been a good fall so far for this species in the Bay Area with multiple sightings in San Francisco and San Mateo counties.
Burrowing Owls - noted in traditional spots in pastures of the Spalleta and Nunes Ranch.
BARN SWALLOW - a late migrant flew over the Drake's Beach visitor center in the morning
Golden-crowned Kinglets - two were in the cypresses above the Mendoza Ranch pond in the afternoon
TRICOLORED BLACKBIRDS - only ~380 noted on the day, with the largest flock of ~300 observed in the pastures above Nunes. While numbers of Tricolored blackbirds typically begin to decline by November one has to wonder what the effect of cessation of ranching activities on the Outer Point will have in the long term on this STATE LISTED species. Tricolored Blackbirds have been studied heavily in recent decades and found to be almost completely dependent on cattle ranches for foraging areas.
Unusual for the date was a near complete absence of American Goldfinches (1!) and low numbers of American Pipits (~40, with the largest flock of 25 flying over Nunes in the afternoon, the rest small groups and singles flying over throughout the day.)
Complete trip report and checklists can be viewed here:
