As we began our walk along Clear Creek on Saturday morning we saw numerous dabbling ducks – Northern Shovelers, Mallards, Gadwall, and Green-winged Teal.  Then, when we got to the various little lakes, we picked up the diving ducks – Ring-necked Duck, Lesser Scaup, Common Goldeneye, and Hooded Merganser.  One of our participants, in having to leave early, also saw a Cinnamon Teal on the creek.  It’s always captivating to watch Northern Shovelers whether on their own, in pairs, or in larger groups of over a hundred swirling around in tight rotating circles thereby creating a whirlpool-like effect that brings food to the surface which their specially adapted bills can filter out.

One of our early surprises was a Greater Yellowlegs.  These guys began showing up regularly about two weeks ago, although I did see a group of thirteen in Weld County on Feb 21.  Our bird on Saturday was most cooperative giving us good views of not only its yellowlegs but also its long slightly upturned bill and the dark bars on its flanks.  To cap things off it gave its distinctive three-note call multiple times.  It’s congener (that is a member of the same genus) the Lesser Yellowlegs always arrives a bit later, generally during the first week of April.  Being able to distinguish between the two species can be challenging.

The island in Tabor Lake in the greenbelt is famous for the Double-crested Cormorants that nest there each year in the large old snags.  I don’t know what the cormorants will do once those snags all fall over, but in the meantime, we counted over ninety birds on nests and hanging out adjacent to the nests.  There were also a few Great Blue Herons in the vicinity and possibly one on a nest next to the cormorants.

Then, there were the Cooper’s Hawks, the Red-tailed Hawks, and the Common Raven.  So, first of all there’s the identification of these three species.  Cooper’s Hawks are the mid-sized accipiters, being more slender and elongated than a buteo, and having the usual accipiter long, banded tail.   More specifically, the head is flat on top and eye-placement is toward the front of the head giving them a more imperious look as opposed to the Sharp-shinned Hawk whose rounded head and more centered eye gives them a less fierce look – almost pigeon-like.  Other features that we noted were that a first-year bird has orange eyes (transitioning from yellow to red), that Coops have a fairly distinctive “kik” call, and that both sexes perform a courtship flight display in which the bright white undertail coverts are flared laterally.  Red-tails, in comparison with other buteos, tend to have more rounded wing tips and “bulging” secondary flight feathers that make the wings look quite broad.  And Common Ravens are distinguished by, among other things, their wedge-shaped tails.  We got to witness some interesting aerial interactions between these three species, most likely related to the hawks starting to incubate eggs.  Our job as observers was to try and figure out who was chasing whom, and oftentimes the roles seemed to reverse – Red-tail chasing Raven, Raven chasing Red-tail, Coop chasing Red-tail, etc.

Certainly, the main highlight of the morning was getting to see a female Rusty Blackbird foraging among the small rounded boulders along the edge of Clear Creek.  Rusties are the least well-known North American blackbirds, breeding in wet subarctic taiga forests along bogs, muskeg swamps, and beaver ponds, and wintering in the eastern United States south of the Great Lakes and occurring rarely in Colorado.  They get their name from their fall plumage when their dark feathers are edged with a rusty brown color.  Over the past forty years for uncertain reasons their numbers have declined by about 90%.  For us to get to see one of these rarities was a definite treat.

Good birding, Chuck

Wheat Ridge Greenbelt 
Mar 23, 2024
39 species
11 participants

Cackling Goose  14
Canada Goose  12
Cinnamon Teal  1
Northern Shoveler  140
Gadwall  35
American Wigeon  2
Mallard  40
Green-winged Teal  21
Ring-necked Duck  3
Lesser Scaup  25
Common Goldeneye  8
Hooded Merganser  12
Mourning Dove  9
American Coot  8
Greater Yellowlegs  1
Ring-billed Gull  25
Double-crested Cormorant  110
Great Blue Heron  5
Cooper’s Hawk  2
Red-tailed Hawk  3
Belted Kingfisher  3
Downy Woodpecker  3
Northern Flicker  14
Blue Jay  10
Black-billed Magpie  2
American Crow  1
Common Raven  1
Black-capped Chickadee  16
Tree Swallow  4
European Starling  14
American Robin  18
Cedar Waxwing  14
House Finch  4
Lesser Goldfinch  1
American Goldfinch  5
Song Sparrow  20
Spotted Towhee  4
Red-winged Blackbird  40
Rusty Blackbird  1