Sombrero Marsh, April 10th–with Morgan Sherwood

It was a beautiful morning of birdwatching and banding at Sombrero Marsh, in partnership with Thorne Nature Experience. We began by taking a short walk down to the bird blind that overlooks the marsh. In addition to the large flocks of Canada Geese, there were quite a few Green-Winged Teal, as well as Mallards and three Gadwalls. While we were watching, two Killdeer showed up on the shore and we enjoyed watching them walk on the beach.

Tree Swallow on nestbox. Photo by Janet Meyer.

As we headed toward Thorne’s education building, we saw two Say’s Phoebes, which was a first for some of our participants from the East coast. While walking back, we also saw a Western Meadowlark perched on a post and talked about its song. We arrived at Thorne’s educational building just as Oak Thorne was showing up to demonstrate bird banding for our group. He has been banding birds for nearly 70 years! He began when  he was 13 years old, and his high school biology teacher introduced him to it. He founded the nature education center named for him in 1954 and it has been connecting kids to the outdoors ever since. 

I started attending nature-themed summer camps with Thorne Nature Experience when I was eight years old and signed up for Oak’s Beginner Bird Banding camp as soon as I was 12 years old. I immediately fell in love with bird banding and have been doing it ever since. While we were waiting for Oak to catch birds in the traps set up near the building, we watched a small flock of Tree Swallows that were conveniently posing on top of some bird houses in front of the beautiful mountain landscape.

Oak Thorne showing off his bird banding feeder trap. Photo by Janet Meyer.

The traps were unusually quiet at first, which seemed mysterious until one of our participants spotted a Cooper’s Hawk in the area–that explained it! The hawk moved on and, soon enough, Oak caught a male Red-Winged Blackbird in one of his traps. The traps have seeds in them and most of the time, when he isn’t banding, they are normal bird feeders, and the birds are accustomed to freely moving in and out of them. When Oak is ready to band, he activates a control panel inside the Thorne building to close the feeder and trap the birds inside.

This bird was not banded and so the group got to see an up-close demo of banding and had the opportunity to hold the bird.

Male Red-winged Blackbird being banded. Photo by Janet Meyer.

One of the participants released it and we once again waited for more birds to come into the trap. While we waited, the Cooper’s Hawk from earlier flew over, as well as a Double-crested Cormorant. After a short while, Oak announced he had caught a whole flock of male Red-Winged Blackbirds. The group went around the back of the building to examine the traps and watch the process of removing birds. As we removed the birds one by one, it became clear that many of them had already been banded. This is quite common, since Oak bands at Sombrero Marsh frequently and even the recaptures provide useful data. For the birds that are already banded, Oak still records all of the information about them as sometimes we will catch a bird multiple years in a row and this provides valuable information about their lifespans. All of his data gets electronically submitted to a national database based in Laurel, Maryland. 

There were a couple unbanded birds in this catch and participants got to use the special bird banding pliers and fit the small aluminum band on the bird’s leg before releasing them again.

Red-Winged Blackbirds are by far the most common birds Oak bands at the marsh, but in the summer he also gets Yellow-Headed Blackbirds, White-Crowned Sparrows, Mourning Doves, and the occasional Blue Jay or American Robin. 

It was a great morning with lots of waterfowl, songbirds, and a bird banding demo with a master bird bander. We were lucky enough to have a photographer come and take lots of pictures of the whole process. A few are included in this post but you can see the whole gallery at this link. Big thank you to Janet Meyer for capturing these shots!

Bird Count:

2 Red-Tailed Hawks

20 Green-Winged Teals

3 Gadwalls

10 Mallards

2 Killdeer

2 Say’s Phoebe

8 Tree Swallows

1 Cooper’s Hawk

1 Cormorant

1 Western Meadowlark

25 Red-Winged Black Birds (10 banded and released)

26 Canada geese

Stearn’s Lake, April 2, 2021–with Sheridan Samano

Early morning has the reputation for being the best time to go birding. It’s definitely a sweet spot for peak bird activity, but as the days get longer, you might find it convenient to bird later in the day.

On April 2, we met at Stearns Lake at 5:30 pm. Even before leaving the parking lot, we had the opportunity to pick out a lone white Snow Goose among a hundred or so Cackling Geese. Snow Geese have a  ‘grin patch’ – a dark patch on the side of the beak that makes the beak look open or like the bird is grinning. It’s not always easy to see the ‘grin patch’, but the setting sun provided ideal lighting conditions to do just that.

Bald Eagle – Second or Third Year. Photo by Sheridan Samano.

It wasn’t long before a Bald Eagle flew over the lake scattering the large flock of geese. Since 2012, a pair of Bald Eagles has nested near Stearns Lake. For several years, their nest was in a large cottonwood tree east of Del Corso Park, a small park wedged between apartment complexes that can be seen to the west of Stearns Lake. Last year, the Bald Eagles moved to a nesting tree south of Stearns Lake. This year, they’re nesting just southwest of the lake, much closer to the trail that leads you along the lake’s south and east shore.

The Bald Eagle that scared off the flock of geese wasn’t one of the adults in the nesting pair. By plumage, it appeared to be a second or third year individual. We watched as it headed straight for the eagle nest tree after flushing the geese. It was then promptly chased off by the adult male. We watched as the young individual approached the nest tree multiple times before being chased off again and again.

As we worked our way along the lake’s south shore, we practiced our waterfowl identification (ID) skills. We spotted a lone Gadwall, several Mallards, a Bufflehead pair, two pairs of Ruddy Ducks, and a Horned Grebe. The cerulean blue bill of male Ruddy Ducks in breeding plumage always rank high on the “wow-index”. We also discussed the distinct profile of Ruddy Ducks in the water –  small body, scoop-shaped bill, and stiff tail often cocked upward.

The Horned Grebe offered another ID challenge. Both Horned and Eared Grebes had been reported in Boulder County recently. In poor light or from a distance, it can be challenging to tell the two species apart. Both are small and compact with black heads and showy head feathers. Neck color in breeding plumage differs between the two species, though. The Horned Grebe has a cinnamon neck and the Eared Grebe a black neck. Again, the setting sun

Killdeer. Photo by Sheridan Samano.

provided ideal lighting to see the cinnamon neck of this Horned Grebe through the spotting scope.

Other highlights of our walk included a pair of American Kestrels, our smallest and most common falcon “pair bonding”, a Great Blue Heron stalking prey in the lake’s shallows, and a Killdeer in beautiful Golden Hour lighting.

As the days continue to get longer in the coming weeks, consider taking an evening bird walk. It’s a wonderful way to end the day.

eBird Checklist – 20 Species

Snow Goose
Cackling Goose
Canada Goose
Ruddy Duck
Horned Grebe
Rock Pigeon (Feral Pigeon)
Great Blue Heron
Bald Eagle
Red-tailed Hawk
American Kestrel
Black-billed Magpie
European Starling
American Robin
Western Meadowlark
Red-winged Blackbird
Great-tailed Grackle


Front Range Birding Company’s blog readers get 10% of Best Birding Hikes – Colorado’s Front Range. Enter discount code FRBC at check out.

Hudson Gardens Bird Walk March 27, 2021

Hudson Gardens Field Trip – Mar 27, 2021 8:00 starting time

Led by Patti Galli

Wow, what a great start this morning! The weather was beautiful – sunny skies with the early temperature hovering around 35 degrees and it just kept getting nicer as the morning went along. Spring is almost here, and with it the migratory birds not far behind. Our first birds were House Finches with their joyful chatter and the American Robin.

American Robin photo by Bill Schmoker

We spent some time looking at the American Robins, since this is one of our most familiar birds, with its lovely rusty-orange breast, uniform dark gray upper side, and dark head.  Some in our group hadn’t noticed before its white markings around the eyes. The American Robin ( Turdus migratorius ) name is the affectionate diminutive of Robert. The name Robin is also associated with at least three particular favorites: Robin Hood, Robin Goodfellow, and Robin Redbreast.

Green-winged Teal photo by Bill Schmoker

We worked our way down to the South Platte river to see if any ducks are were still here. This time of year our wintering ducks start making their way north to their breeding grounds. Turns out there were still a few left to look at. The Gadwalls, American Widgeon, and Bufflehead ducks still gave us one more good glance.  Our year round ducks of course such as the Mallards, Canada Geese, and one last fun surprise- the Green-winged Teal treated us as well!  

The Green -winged Teal is our smallest duck.  The male has a dark rufous head with green patch behind the eye, a white belly, and white bar on the side of the breast. The female has a rather dark, indistinctly marked faint eye ring and dark line across the check.


We finished up at the bird feeders, where we sat and watched Black-capped Chickadees, Dark-eyed Juncos, and hearing in the distance, the loud sounds of Red-winged Blackbirds.

Truly a wonderful morning!

eBird Report: Hudson Gardens, Arapahoe, Colorado, US
Mar 27, 2021 8:00 AM – 10:50 AM
Protocol: Traveling
1.0 mile(s)
Checklist Comments:     Led trip for Front Range Birding Comp/Hudson Gardens . Cool 32* start , no wind , sunny , beautiful morning
22 speciesCanada Goose  15
Gadwall  11
American Wigeon  8
Mallard  20
Green-winged Teal  2
Bufflehead  7
Ring-billed Gull  5
Belted Kingfisher  1
Downy Woodpecker  2
Say’s Phoebe  2
Blue Jay  2     heard
Black-billed Magpie  2
American Crow  5
Black-capped Chickadee  10
Bushtit  9
Red-breasted Nuthatch  2     heard
European Starling  6
American Robin  10
House Finch  11
Dark-eyed Junco  3
Song Sparrow  1     heard
Red-winged Blackbird  25View this checklist online at

Hudson Gardens Feb 27, 2021

Leader Patti Galli, nine participants. Sunny, clear and 24 degrees at 8:00 starting time.

It turned out to be another beautiful Colorado morning.  The temperature was indeed wonderful and we spotted a total of 23 species.We saw several common visitors in and around the area. Most of our group really considered themselves asbeginners, but they all turned out to be good spotters. 

We made our way to the South Platte river and saw many of our winter visitors. They were beautiful! We got a real kick out of the Canada Geese. We laughed as this behemoth bird made a cracking, crunching sound as they walked on the ice. This bird is an incredible flyer and a great survivor as well!  The Canada Goose (not Canadian) was once esteemed as “ the noblest of our waterfowl,” and bred mostly in Canada and in Alaska. It used to migrate until man interfered with this pattern – they are now found almost everywhere and are often considered a messy nuisance.  However, the Canada Goose  didn’t expand its range on its own; it had human help. Beginning in the 1950’s it was introduced throughout the country to ensure there would be plenty to hunt- so there you have (some of) it!

Canada Geese photo by Bill Schmoker                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   

The challenge is almost often ducks, such as the American Wigeon. We saw a perfect adult male in breeding plumage, with its green patch leading back from the eye, white forehead, brownish breast and flanks, white belly, black undertail and uppertail coverts, and a green speculum bordered with black.

American Wigeon Photo by Bill Schmoker

What is a covert feather? A covert feather on a bird is a set of feathers, which as the name implies, covers other feathers. They help to smooth airflow overthe wings and tail. It’s one of the many things to help ID a bird. And a speculum? The speculum is a patch, often distinctly colored, on the secondary wing feathers of some birds.


Red- Brested Nuthatch photo by Bill Schmoker








We spent some time too looking at Buffleheads, Ringed-necked duck, Gadwalls, and the Common Goldeneye. We ended our lovely walk with the sounds and sights of Black-capped Chickadees, House Finches and two adorable Red – breasted Nuthatches, which was a favorite as well! We’re looking forward to spring as we’ll welcome our spring migrates, but it’s nice to enjoy our year-round birds as well, for there is no such thing as a common bird!

Hudson Gardens, Arapahoe, Colorado, US
Feb 27, 2021 8:00 AM – 10:20 AM
Protocol: Traveling
1.4 mile(s)
Checklist Comments:     Leader myself, Patti Galli , and 8 participants. Sunny start , no wind 24*
22 species (+1 other taxa)Canada Goose  100
Gadwall  5
American Wigeon  3
Mallard  4
Ring-necked Duck  3
Bufflehead  8
Common Goldeneye  7
Ring-billed Gull  5
Accipiter sp.  1
Downy Woodpecker  2
Northern Flicker  2
Black-billed Magpie  1
American Crow  4
Black-capped Chickadee  5
Bushtit  1
Red-breasted Nuthatch  2
White-breasted Nuthatch  1
European Starling  7
American Robin  2
House Finch  12
Dark-eyed Junco  2
Song Sparrow  1
Red-winged Blackbird  2View this checklist online at

This report was generated automatically by eBird v3 (

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Walden Ponds, February 27th–Sheridan Samano

Walden Ponds, Sawhill Ponds and Boulder Creek – February 27, 2021 – with Sheridan Samano

Last Saturday morning, there was enough interest for two different bird walks at the Walden Ponds/ Sawhill Ponds Complex in Boulder. Both groups met at Cottonwood Marsh, but with different start times and routes. The avian highlights varied substantially between the two walks.

To start, the 8 am group noticed several male Red-winged Blackbirds displaying and singing in the cattails on the south side of the marsh. It won’t be long before we see an influx of even more males and females as spring progresses and breeding season is in full swing.

From Cottonwood Marsh, we headed to the northwest corner of Duck Pond where the group started practicing their duck ID skills. In winter, ducks showcase their fine-feathered breeding plumage so this time of year offers excellent opportunities to learn how to distinguish between common species in the area. At Duck Pond, we found Hooded Mergansers, Ring-necked Ducks, Gadwalls, American Wigeon, and Mallards. As we watched the various individuals from the same species, we noticed that members of the same species tend to move together in groups. Female ducks are harder to distinguish, but they’re often traveling with male counterparts. Those observations can help birders ID ducks on future outings.

Each pond we passed offered a different collection of waterfowl so we had several opportunities to practice telling species apart. Finding a large group of male Green-winged Teal in a large pond north of Duck Pond, the smallest dabbling duck in North America, was a highlight for everyone. Green-winged Teal are often found at shallow edges of ponds. They often walk along muddy edges, too.

By the time the second walk started at 10:15 am, the skies were clearing and it was much warmer. These conditions favored raptor activity so the focus of the second walk shifted from examining ponds to searching perches and the sky overhead.

An adult Bald Eagle perched noticeably on a tower east of Cottonwood Marsh greeted the group. This individual was likely from the pair that nests east of 75th Street. We could see the second half of the pair at the nest tree.

Instead of heading due west from Cottonwood Marsh as we did during the first walk, we headed north towards Boulder Creek. On the west side of Cottonwood Marsh, we spotted a male American Kestrel perched on a stump with his back to us. This view provided an opportunity to discuss coloration differences among the sexes of North America’s smallest falcon. Female Kestrels don’t have blue-gray wings like males. We got a second, better look at this male later in the walk.

Other raptor highlights during the second walk included multiple Red-tailed Hawks, a third year Bald Eagle, and a Golden Eagle. A member of our group mentioned she was hoping to see a Golden Eagle this morning so having one fly overhead at the end was an excellent way to end our morning of birding.

The Walden Ponds and Sawhill Ponds Complex is featured in Best Birding Hikes – Colorado’s Front Range. The Complex offers some of the best year-round birding opportunities in Boulder County. No matter the month, a birding outing here is sure to deliver.

22 Species Observed during 8 am Bird Walk (eBird Checklist)

Canada Goose – 13

Northern Shoveler – 5

Gadwall – 24

American Wigeon – 10

Mallard – 25

Green-winged Teal – 20

Ring-necked Duck – 6

Common Goldeneye – 1

Hooded Merganser – 30

Common Merganser – 10

Great Blue Heron – 8

Red-tailed Hawk – 2

Northern Flicker – 4

Blue Jay – 5

Black-billed Magpie – 2

American Crow – 1

Black-capped Chickadee – 8

European Starling – 2

American Robin – 2

House Finch – 2

Song Sparrow – 1

Red-winged Blackbird – 30


29 Species + 1 Other Taxa During 10:15 am Bird Walk (eBird Checklist)

Cackling Goose – 2

Canada Goose – 28

Cackling/Canada Goose – 90

Northern Shoveler – 2

Gadwall – 11

American Wigeon – 8

Mallard – 40

Green-winged Teal – 1

Ring-necked Duck – 10

Common Goldeneye – 1

Hooded Merganser – 14

Common Merganser – 5

Rock Pigeon (Feral Pigeon) – 8

Great Blue Heron – 1

Golden Eagle – 1

Bald Eagle – 3

Red-tailed Hawk – 4

Northern Flicker – 1

American Kestrel – 1

Blue Jay – 4

Black-billed Magpie – 1

Common Raven – 1

Black-capped Chickadee – 4

White-breasted Nuthatch – 1

European Starling – 6

American Robin – 1

House Finch – 3

Song Sparrow – 2

Red-winged Blackbird – 46

Yellow-rumped Warbler – 1


Sandstone Ranch, February 13–with Aron Smolley


American Tree Sparrow. Photo by Jamie Simo.

It was an honor and a pleasure to lead my first bird walk for Front Range Birding Company this morning. Although the temperatures never quite got above 4 degrees Farenheit, our small group had a fantastic time braving the elements in search of birds at Sandstone Ranch.

A lone American tree sparrow greeted us at the bottom of the hill, and we started off scanning the mostly frozen river for waterfowl, and mostly turned up Canada and Cackling geese as well as mallards, but we did get some great views of the local muskrat going about it’s day on the ice like it was no big deal. As soon as we crossed the first bridge we dicovered a pair of American kestrels, a male and female sitting side by side, feathers puffed up for warmth, and shortly after that we had a pair of red-tailed hawks soaring

Northern Pintail drake. Photo by Jamie Simo.

in the distance in what appeared to be early courtship behavior. An adult bald eagle sat perched next to a partially completed nest as black-billed magpies fluttered by.

Scanning the river we managed to turn up a few gadwall among the mallards, and a Northern pintail was a “lifer” for one of our participants. We also found some more bonus mammals- a small herd of white-tailed deer and a mink! A little further upstream we had a female hooded merganser ducking and diving beneath the icy water. At this point, we made a group decision to start making our way back to the parking lot, stopping occasionally for interesting waterfowl such as a common goldeneye, as well as some little brown birds that had to be left unidentified (I blame fogged-up, iced over binoculars and shivering hands!)

When we got back to the main trail we had a soul-satisfying view of an immature bald eagle that flew low and slow over our heads, and at that point my falcon senses started tingling so I started scanning the sandstone cliffs. To my delight, a prairie falcon (a lifer for ALL the partipants of this bird walk!) was perched in plain view at the edge of the cliff so we took a small detour so that everyone could get a closer look. The final bird of the day- a special bonus I might add- was a merlin that zipped by, giving us all of 3 seconds to confirm it’s identity before disappearing over the horizon. Our third falcon species and the perfect ending to a wonderful, albeit frigid, bird walk.

Here is our complete list of (confirmed) birds seen:
Canada goose-110

Merlin. Photo by Jamie Simo.

American crow- 17
Am. tree sparrow- 1
Mallard- 48
Cackling goose- 37
American kestrel- 2
Black-billed magpie- 3
Red-tailed hawk- 2
Gadwall- 4
Western meadowlark- 3
Northern pintail- 2
Bald eagle- 2
Hooded merganser- 1
Common goldeneye- 1
Prairie falcon- 1
Merlin- 1

Walden/Sawhill Ponds Complex, March 14th – with Stephen Chang

The Saturday of March 14th, I led a group of 7 on a chilly morning to Walden Ponds wildlife habitat for our monthly birdwalk. We won’t be having another walk until, at the earliest, May 9th (maybe later), but we made the most of our last walk by observing 31 different species! Highlights included at least four different Bald Eagles (two adults and two juveniles), the area’s winter resident Harlan’s Hawk, and a very cooperative Northern Shrike.

Northern Shrike (c) Sibylle Hechtel


Northern Shrikes are a winter visitor here to the front range, but they breed up in the arctic tundra/taiga. Shrikes are our only predatory songbird, and during the winter the Northern Shrike will eat mostly other small songbirds and small rodents. In arid, open habitats across the front range, the Northern Shrike is replaced by the Loggerhead Shrike in the summer. They will eat small birds, mammals, reptiles, and insects.

Loggerhead Shrike (c) Jamie Simo


Our full eBird checklist can be found here: 


There is still plenty of migration to be had, so be sure to get out and look at some birds. Spending time in our natural areas is a easy way to practice social distancing. Happy Spring and be well!


Stephen Chang

Milavec Reservoir, Jan 11, 2020–with Jamie Simo

Cackling Goose (left) vs Canada Goose (right) (c) Jamie Simo

Milavec Reservoir in Frederick, CO is one of the best places along the Front Range to see all the possible (read: non-rare) interior goose species. Sometimes, like last year, it even plays host to some rarities like the Colorado-record Pink-footed Goose and Barnacle Goose. As hoped for, while we didn’t see any Colorado-record geese on this frigid, but sunny, Saturday morning, we did see all the usual goose suspects. We also had some great ducks and raptors.

Nearly all Coloradans are familiar with our only breeding goose species, the Canada Goose, but winter brings migrant Cackling, Greater White-fronted, Ross’s, and Snow Geese from the arctic to our lakes, reservoirs, and fields. The most similar to the Canada Goose, the Cackling Goose was only recognized as a species in its own right in 2004. There are 4 subspecies of Cackling Goose varying in size and color, but some of the common characteristics include smaller body size than the majority of Canada Geese (there may be some overlap with the smallest subspecies of Canada Goose), a shorter neck, and a bill that looks “stubby” because of a more rounded or square head shape. Because of the difficulty of distinguishing between the smallest subspecies of Canada Goose and the largest subspecies of Cackling Goose, small white-cheeked geese are sometimes referred to as “Cackling-ish.”

Ross’s Goose (foreground) vs Snow Goose (background) (c) Jamie Simo

Like the Canada Goose, the Snow Goose also has a “mini-me” doppleganger, the Ross’s Goose, but that doppleganger is much easier to pick out than the Cackling Goose. Firstly, Snow Geese come in either the expected white plumage with black wingtips or a darker, grey-blue body plumage with white head and neck. Both have pink bills and feet as adults. The latter is sometimes referred to as a “blue goose, “blue morph,” or “blue phase” Snow Goose. There are only 2 subspecies of Snow Goose, but both have a black “grin patch” that gives them a sneering appearance, and a sloping forehead. By contrast, the Ross’s Goose, which is usually white but also occurs rarely in a blue phase, has a steep forehead leading to a rounded crown and lacks the grin patch.

The final expected goose species in Colorado is the Greater White-fronted Goose. This goose is mostly brownish-grey with darker belly bands, orange legs and bill, and white feathers around the base of the bill from which is gets its name.

Other stand-out species were 2 adult Bald Eagles, a Northern Harrier, a Red-breasted Merganser, a female Canvasback, and even a coyote. Not bad for a cold, January morning!

Female Northern Harrier (c) Chris Friedman

Frederick Lake (Milavec Reservoir) & Recreation Area, Jan 11, 2020
25 species

8 Snow Goose
3 Ross’s Goose
1 Greater White-fronted Goose
2000 Cackling Goose
4000 Canada Goose
60 Northern Shoveler
10 Mallard
1 Canvasback
7 Lesser Scaup
3 Bufflehead
20 Common Goldeneye
7 Common Merganser
1 Red-breasted Merganser
1 Ruddy Duck
3 American Coot
1 Northern Harrier
2 Bald Eagle
1 Red-tailed Hawk
1 American Kestrel
1 Blue Jay
6 European Starling
6 American Tree Sparrow
1 White-crowned Sparrow (Gambel’s)
2 Song Sparrow
1 Red-winged Blackbird

Boulder Reservoir, November 9, 2019–with Aidan Coohill

Female Ruddy Duck (c) Jamie Simo

We started our walk at Boulder Reservoir with excellent sunny weather and low wind, allowing us to see the birds on the lake quite easily without many waves. Boulder Reservoir is the largest reservoir in the county in terms of both size and volume creating an excellent environment for birds but also for recreational boating, fishing, swimming, and jogging. It also provides and holds all water for the Northern Water Distinct for drinking and irrigation. We covered the area in two sections, the first on the southwestern shore of the reservoir which is extremely popular in summer for recreation, and the northern section from the West Reservoir Trailhead. 

Immediately after parking we found a large group of American coots feeding in the shallows of the swim beach. Among the flock was a lone female Ruddy duck. Belonging to the genus of “Stiff-tailed ducks”, it is a small freshwater fowl with a large range across North America. Like all in its genus, the Ruddy duck has a stiff tail (often described as looking like a bundle of Popsicle sticks), males have a bright blue bill, and a body that depending on season and sex is rusty to brown in color. These birds are currently in the process of moving to their warmer wintering grounds further south in the Unites States and into Northern Mexico. 

Bonaparte’s Gull (c) Jamie Simo

Further down the shoreline we found the Rusty blackbirds that have been seen in the area for the last several days, a rarity that drew many local birders to the reservoir. This blackbird is very similar to the Brewer’s blackbird that is common in Colorado but is an uncommon accidental migrant in this part of the west. Unlike the Brewer’s blackbird, it prefers quiet spruce forest and boreal bog and not parks, fields, pastures, lawns, and parking lots. During winter the differences between the sister species becomes most obvious with both the male and female getting buffy and ruddy patterning on their bodies. This was the state the pair we saw were in. 

On the north side of the reservoir we got another cool sighting, two Bonaparte’s gulls. This small bird is the smallest gull in North America aside from the elusive Little gull. They have dainty pink feet, a small beak, and off-white coloring. During winter plumage (what we saw) it trades its distinctive black hood for white save for a small black patch over the ear. These gulls are a real treat as they head south for the winter. 

Other highlights included a Ferruginous hawk perched in a tree on our way out, a pair of Northern harriers, and all three species of mergansers!

In all, we heard or saw 28 taxa; good for this time of year at the reservoir! 

Boulder Reservoir, November 9, 2019
27 Species (+1 additional taxa)
  • Cackling Goose 250
  • Canada Goose 100
  • Gadwall 2
  • Mallard 2
  • Lesser Scaup 1 
  • Common Goldeneye 8
  • Hooded Merganser 15
  • Common Merganser 8
  • Red-breasted Merganser 6
  • Ruddy Duck 1
  • Horned Grebe 1
  • Western Grebe 6
  • American Coot 80
  • Bonaparte’s Gull 2
  • Ring-billed Gull 200
  • Herring Gull 1
  • Great Blue Heron 1
  • Northern Harrier 2
  • Red-tailed Hawk 3
  • Red-tailed Hawk (Harlan’s) 1
  • Ferruginous Hawk 1
  • Blue Jay 1
  • Black-billed Magpie 2
  • Black-capped Chickadee 2
  • European Starling 100
  • House Finch 4
  • Red-winged Blackbird 1
  • Rusty Blackbird 2

If anyone would like me to share the eBird checklist with them please email me at

Hudson Gardens, Sept 28, 2019 – with Chuck Aid

Wood Duck – juvenile male (c) Bill Schmoker

We had an incredibly entertaining start to our walk on Saturday.  This year mama Wood Duck had about eight fledglings back in July.  Last month we were thrilled to see that six of them were still around, and we were able to tell that they were all males.  We could see the characteristic bright white “bridle” that the males have on their neck and cheek, even though the rest of the outrageous male plumage hadn’t quite emerged. On Saturday we were able to see, once again, all six of this year’s juvenile males.  Not too much had changed from a month ago except that they were considerably bigger (almost adult sized), there was starting to be some color definition in the bill, their eyes were getting red, and we could see some of that wonderful deep bluish turquoise in their speculums (the secondary flight feathers). However, they also still had their white eye-rings that are characteristic of juvenile birds.

Wood Duck – female (c) Bill Schmoker

Beyond the six youngsters we also had an adult female Wood Duck (mom?), and three adult males.  These latter were all in the process of emerging from their eclipse plumage phase when the males go through a sequence of molts causing them to look more drab, like their female counterparts.  It can take them awhile to regain their full male splendor, and all three of our Saturday males had different degrees of white speckling in what will become eventually a mostly burgundy-colored breast.  Part of what was so cool about this herd of Wood Ducks is that they were all tending to hang out together foraging in the grass along with some companionable female Mallards, and they were not worried about us at all.

Killdeer (c) Bill Schmoker

As we moved over to the South Platte we saw more Mallards – the males in a mix of plumages between cryptic brown and bright breeding colors, as they, too, are emerging from their eclipse plumage. We also were fortunate to see some Killdeer and a single Spotted Sandpiper which actually will have no spots until next March at the advent of breeding season. 

Cedar Waxwing (c) Bill Schmoker

We also encountered a nice flock of Cedar Waxwings, being a mix of beautiful warm-brown adults and streaky juveniles.  In the adults some of the secondary flight feathers have bright red tips from a waxy red secretion resembling sealing wax.  Historically, Cedar Waxwings were considered uncommon breeders in Colorado, being more common during spring and fall migration and throughout the winter.  However, in more recent years the number of breeders have increased dramatically along water courses in North, Middle, and South Parks and the San Luis Valley.  The resultant increase in the Colorado population may be due to a number of factors: an increase in edge habitat which promotes the growth of fruiting trees and shrubs, the planting of non-native fruiting trees and shrubs, the planting of shelter-belts, and the ongoing increase in Russian olives.

Great Blue Heron (c) Bill Schmoker

One of the topics that came up on our walk was about those species that breed in Colorado and afterwards most of them migrate south, but there are always a few individuals that stick around throughout the winter.  We were speaking primarily of Great Blue Herons, but there are quite a few others that follow this pattern such as American Kestrel, Killdeer, Mourning Dove, Say’s Phoebe, American Robin, and Spotted Towhee.

Undoubtedly the highlight of the morning was getting to watch a juvenile Red-tailed Hawk from about twenty feet away (I kid you not!) eviscerate a cottontail.  I’m thinking that as a youngster it still may have been learning the craft of capturing its own prey, and perhaps it was so darn hungry it just did not care whether we were there or not.

Hope to see you on another walk soon!


Hudson Gardens, Sept 28, 2019
27 species

Red-tailed Hawk- juvenile (c) Bill Schmoker

Canada Goose  6
Wood Duck  10
Mallard  32
Rock Pigeon (Feral Pigeon)  2
Broad-tailed Hummingbird  2
Killdeer  4
Spotted Sandpiper  1
Ring-billed Gull  1
Great Blue Heron  1
Turkey Vulture  1
Red-tailed Hawk  2
Downy Woodpecker  1
Northern Flicker  10
Say’s Phoebe  2
Blue Jay  8
Common Raven  1
Black-capped Chickadee  8
Red-breasted Nuthatch  2
White-breasted Nuthatch  3
European Starling  2
American Robin  4
Cedar Waxwing  20
House Finch  14
Lesser Goldfinch  1
Song Sparrow  3
Red-winged Blackbird  6
Yellow-rumped Warbler  2