It’s Sunday, which means we get another batch of themed bird photos from John Avise. John’s narrative and IDs are indented, and you can click on the photos to enlarge them.

Brood Parasitism (also known as “egg dumping”)

This is a phenomenon in which a female lays one or more of her eggs in the nest of another bird, leaving the duties of incubation and hatchling rearing to the duped foster parents.  Brood parasitism can be intraspecific (when the brood parasite and the host belong to the same species) or interspecific (when the brood parasite and the host belong to different species).  Brood parasitism may also be facultative (when the brood parasite dumps her eggs only occasionally) or obligatory (when the brood parasite always employs this lifestyle).  Here in Southern California we have two obligate interspecific brood parasites: the Pin-tailed Whydah (Vidua macroura) and the Brown-headed Cowbird (Molothrus ater), neither of which apparently ever rear their own young.

The Whydah is native to sub-Saharan Africa where it uses Estrildid finches as its parasitized hosts.  In Southern California, the introduced Whydah uses another introduced species, the Scaly-breasted Munia (Lonchura punctulata) as its primary host.  This Munia is an Estrildid finch that was introduced to California from its native home in Southeast Asia.

The Brown-headed Cowbird is native to North America where it parasitizes a wide range of native host species, sometimes so severely that it can seriously impair normal reproduction by its host. Indeed, brood parasitism by the cowbird can be so detrimental to the nesting success of other native species (including some endangered ones) that wildlife managers here in Orange County sometimes set out special traps to try to capture and eradicate the nest-parasitic cowbirds.

This week’s post shows these two obligate brood parasites and some of their commonly employed host species.  All photos were taken in Southern California.

Pin-tailed Whydah adult male:

Pin-tailed Whydah female:

Pin-tailed Whydah juvenile:

Scaly-breasted Munia adult:

Another Scaly-breasted Munia:

Scaly-breasted Munia juvenile:

Brown-headed Cowbird male:

Brown-headed Cowbird female:

Brown-headed Cowbird juvenile:

Common Yellowthroat (Geothlypis trichas) male (this species is a commonly parasitized host for the Brown-headed Cowbird):

Common Yellowthroat female:

Bell’s Vireo (Vireo bellii) (this endangered species is another commonly parasitized host for the Brown-headed Cowbird):

Another Bell’s Vireo:

Today’s batch of bird photos comes from reader Paul Edelman, an emeritus professor of law and mathematics at Vanderbilt. Paul’s narrative is indented, and you can enlarge his photos by clicking on them.

  We spent a couple of weeks at the beginning of January in and around Naples, Florida and had a great time birding.  I have two batches for you.  The first is birds that spend most of their time in the trees or air, the second will be on birds who inhabit marsh and shore.  [JAC: stay tuned.] All the photos were taken with my trusty Nikon D500 and Nikkor 500mm f5.6 lens.

On the drive down to Naples we stopped overnight in Ocala, FL and had a chance to do some birding at the Ocala Wetland Recharge Park.  Amazingly, we saw two new birds for us, the Red-headed Woodpecker (Melanerpes erythrocephalus) (is there a more aptly named bird?) and the Orange-crowned Warbler (Oreothlypis celata) (which is decidedly inaptly named, since the orange crown is almost never evident.)  Not a bad way to start the trip.

Red-headed Woodpecker:

Orange-crowned Warbler:

One of our favorite birding sites is the Audobon Corkscrew Swamp Sanctuary, located northeast of Naples. Here we saw the Black-and-White Warbler (Mniotilta varia), the Blue-headed Vireo (Vireo solitarius) and the White-eyed Vireo (Vireo griseus),  Even better we caught sight of the Short-tailed Hawk  (Buteo brachyurus). The only place in the US to see this hawk is  south Florida and it was another new bird for us.

Black-and-White Warbler:

Blue-headed Vireo:

White-eyed Vireo:

Short-tailed Hawk:

We drove up to another favorite spot, Harns Marsh, which is northeast of Fort Meyers. Mostly we saw shore and marsh birds there, but there is always an abundance of Black Vultures (Coragyps atratus).

Black Vulture:

Finally we went to a new location south of Naples, Eagle Lakes Community Park where we caught a pair of Loggerhead Shrikes (Lanius ludovicianus) hunting from the telephone wires.

Loggerhead Shrikes:

Today’s bird photos come from ecologist Susan Harrison at UC Davis. Her notes and IDs are indented, and you can click on the photos to enlarge them.

Various Rarities  

Species can be rare in different ways:  found only in a small geographic area, or in a specialized habitat, or widespread and yet scarce or declining. Birds can also be vagrants, showing up far from their normal ranges and causing excitement among local birdwatchers, as described recently by John Avise.  Here are some of the rarer species I’ve been lucky to see in California and southern Oregon.

California Condor (Gymnogyps californianus):

These giant carrion-eaters have such powerful gizzards that they grind up and absorb the lead shot found in many of the carcasses they eat, causing lead poisoning and the near extinction of the once wide-ranging species.  Their numbers have grown since Federal endangered listing led to a program of captive breeding and release, blood chelation, and an effort to get hunters to replace lead shot with steel shot. “Condor 25” here is in one of the more reliable places to see them, Pinnacles National Park in the central California Coast Range.

Ridgway’s Rail (Rallus obsoletus):

This Western US and Mexican marsh denizen is Federally endangered because of habitat loss and introduced predators, besides which it’s a rail and therefore a darned shy bird.  I’ve met biologists who study them and yet have only rarely seen them. I stumbled across this leg-banded individual in the Tijuana River Estuary on the outskirts of San Diego.

Northern Spotted Owl (Strix occidentalis caurina):

This Federally-listed threatened owl became quite the conservation cause in the 1990s.  It needs lush old-growth conifer forest in which to swoop between trees catching woodrats and flying squirrels.  It  has lost much of its habitat, and Barred Owls (Strix varia) are beating up on and maybe hybridizing with it. Helped by an expert, I saw this mom and chick at a southern Oregon location that cannot be divulged lest the neighboring landowners find out.

Great Gray Owl (Strix nebulosa):

This glorious owl is found in both Old and New World northerly forests.  It’s not endangered, but it’s well-camouflaged and not terribly abundant anywhere.  To find it, you have to go somewhere it’s known to occur and carefully examine tree trunks along meadow edges. It’s most easily seen in spring, when parents are flying around catching the dozens of voles per day they need for their chicks. This youngster and its sibling (just above it, with tail tip visible) were in southern Oregon.

Purple Martin (Progne subis):

Much less common in the Western than Eastern US, Martins are declining because European Starlings (Sturnus vulgaris) outcompete them for nest cavities.   This male and his mate were nesting in a telephone pole at the McLaughlin UC Natural Reserve in the inner North Coast Range.

Costa’s Hummingbird (Calypte costae):

This diminutive beauty isn’t rare in the Sonora and Mojave Deserts, but one male became a celebrity when he showed up in the fifth-story rooftop garden of an Oregon retirement community.  I was fortunate to get there when friendly residents were ushering birders up the elevator to admire him, before management put a stop to that.

Eurasian Wigeon (Mareca penelope) in a flock of American Wigeons (Mareca americana):

When this orange-headed visitor strays over from Iceland to the East Coast, or from Russia to the West Coast, it likes to hang around with its American cousins.  This one was in the Yolo Bypass Wildlife Area between Davis and Sacramento.

Yellow-Bellied Sapsucker (Sphyrapicus varius):

Another vagrant I saw last year was this Eastern North American woodpecker with its name that sounds like a playground taunt.  Most woodpeckers don’t migrate, but this species does, and perhaps getting lost on migration was why this one ended up in a Davis city park.

Winter Wren (Troglodytes hiemalis):

This thumb-sized Eastern North American bird with a huge voice was recently split by taxonomists from the Pacific Wren. The two species look quite similar but their magnificent songs are different.  When it showed up in a tangle of brush along a creek near Davis, this one attracted many birdwatchers.

Palm Warbler (Setophaga palmarum):

This warbler breeds in the Canadian boreal forest, migrates across the eastern US, and winters in the Caribbean and a bit of the southeastern US. It also winters very sparsely along the California coast. This one drew birdwatcher traffic to a ditch beside an almond orchard south of Davis, where it was foraging amongst Yellow-Rumped Warblers (Setophaga coronata).

Today is Sunday, ergo John Avise has provided us with a themed batch of bird photos. His narrative and IDs are indented, and you can enlarge his photos by clicking on them.

Throats and Chins

Last week’s post featured avian species with colorful caps and the word “crown” in their official names.  Another colorful area in the plumages of many birds is the general region under the bill.  This week’s post shows several examples in which the common name of the species refers to the color of the bird’s throat or its chin.  Unless otherwise noted, all photos were taken in Southern California.

Ash-throated Flycatcher, Myiarchus cinerascens:

Black-chinned Hummingbird, Archilochus alexandri:

Black-throated Sparrow, Amphispiza bilineata:

Black-chinned Sparrow, Spizella atrogularis:

Black-throated Blue Warbler, Dendroica caerulescens (Florida):

Black-throated Gray Warbler, Dendroica nigrescens:

Yellow-throated Warbler, Dendroica dominica (Florida):

Common Yellowthroat, Geothlypis trichas:

Ruby-throated Hummingbird, Archilochus colubris (Michigan):

Red-throated Loon juvenile, Gavia stellata (only the breeding adult shows a bright red throat):

Yellow-throated Vireo, Vireo flavifrons (South Carolina):

White-throated Sparrow, Zonotrichia albicollis:

White-throated Swift, Aeronautes saxatalis:

Today is Sunday, and John Avise never lets us down with bird photos on goyische cat Sabbath. Today John concentrates on birds’ topknots. His IDs and narrative are indented, and you can enlarge his photos by clicking on them.

Caps and Crowns

Some avian species with otherwise conservative plumages show splashes of color on their caps, and this diagnostic feature is highlighted in their official common names that include the word “crowned”.  Some of these birds are the subject of this week’s post.  The function of such head patches is not always clear, but in at least some species (such as the Ruby-crowned Kinglet and the Orange-crowned Warbler), the feature is found only in adult males and is displayed mainly during courtship or in male-to-male disputes. The parrots, like the rest of these birds, were photographed here in Southern California where feral populations reside (the descendants of pet-store escapees).  But the parrots are native to Latin America.

Ruby-crowned Kinglet, Regulus calendula:

Another Ruby-crowned Kinglet:

Violet-crowned Hummingbird, Amazilia violiceps (Arizona):

Orange-crowned Warbler, Vermivora celata (the orange on the crown normally remains hidden):

White-crowned Sparrow adult, Zonotrichia leucophrys:

White-crowned Sparrow juvenile:

Golden-crowned Sparrow, Zonotrichia atricapilla:

Rufous-crowned Sparrow, Aimophila ruficeps:

Lilac-crowned Amazon, Amazona finschi:

Red-crowned Amazon, Amazona viridigenalis:

Yellow-crowned Night Heron, Nyctanassa violacea:

Black-crowned Night Heron, Nycticorax nycticorax:

Black-crowned Night Heron headshot: