Month: August 2022

By Jim Gain

Post #6 in the Learn 100 Common Valley Birds series. (Species 10/100.)

The Loggerhead Shrike is a Fairly Common Resident to California’s Central Valley and can be found in grasslands, freshwater wetlands and chaparral habitats. There are 2 species of Shrike regularly found in the US, the Loggerhead Shrike and the Northern Shrike. However, the Northern Shrike is a very rare vagrant to the Central Valley.

Valley Species of Special Concern Series

A Species of Special Concern (SSC) is a species, subspecies, or distinct population of an animal native to the Central Valley that currently is listed as a Federal Endangered, California Endangered or California Species of Special Concern.

Status

Loggerhead Shrikes are currently considered a Bird Species of Special Concern (breeding), priority 2. Over their historic range, numbers are slightly declining overall with a dramatic drop in breeding populations in the southern part of the state. This species was described as common to abundant in the San Joaquin Valley in 1927 by Grinnell and Wythe, but recent Christmas Bird Count (CBC) results show an accelerated statewide decline from 1959 to 1988. (See California Bird Species of Special Concern Report)

Description

The Loggerhead Shrike is one of two shrikes regularly found in the US, but is the most expected shrike in the Central Valley. Its close cousin, the Northern Shrike is a very rare winter visitor here with only one record in Stanislaus County. Roughly the size of a starling, this gray and white perching bird can frequently be seen along roads hanging on to a barbed-wire fence. Its large head with bold black mask distinguish the Loggerhead Shrike from the similar colored Northern Mockingbird.

Habits

When disturbed, the Loggerhead Shrike will drop down and fly low along the ground before swooping up to gain another perch on the same fence line. The Loggerhead Shrike is quite the bold predator, often taking on large prey and then impaling it on a barbed-wire or thorn. It has been given the nickname of “butcher bird” due to this curious, yet gruesome behavior.

Distribution

More common in the winter than in the summer, Loggerhead Shrikes can be found in open areas such as grasslands and wetlands. They can be frequently seen along the grasslands along the eastern valley roads (Merced Falls Rd., Willms Rd., Sonora Rd.) or in the grasslands and wetlands areas (Santa Fe Grade, Sandy Mush Rd.) in Merced County. Check out the eBird Loggerhead Shrike species map.

Simliar Species

Though very rare in the Central Valley, the Northern Shrike is very similar in appearance to the Loggerhead Shrike. Northern Shrikes are bigger than Loggerheads. Northern Shrikes have a larger, more strongly hooked bill. Other reliable marks include the Northern’s narrower black mask that usually does not continue in front of their eye (or continue above the bill), and the Northern’s more strongly barred underparts. Both these field marks can be difficult to see in the field.

Check out the comparison between the two species below.

Previous posts from the Learn 100 Common Valley Birds series,

• Common Valley Phalaropes
• Pigeons and Doves
• Tree-creeping Birds
• LBBs – Little Brown Birds
• Coots and Gallinules

By Jim Gain

Post #5 in the Learn 100 Common Valley Birds series. (Species 9/100.)

About Juncos

The Dark-eyed Junco is a Common Winter Visitor to California’s Central Valley and can be found in many habitats. There are 2 species of Junco in the US, the Dark-eyed Junco and the Yellow-eyed Junco. However, the Yellow-eyed Junco is only found in SE Arizona and is not going to be found in the Central Valley. Check out the comparison between the two species below.

The Dark-eyed Junco is a small, sparrow-sized bird that is in fact, a member of the sparrow family (Passerellidae). Juncos are granivorous (seed-eating) ground-dwelling birds that are almost always found in small flocks.

While it is often found in close proximity to White-crowned and Golden-crowned Sparrows at backyard feeders, it is actually more closely related to the more secretive Fox Sparrow.

Dark-eyed Juncos are known as habitat generalists. In the field of ecology, classifying a species as a generalist or a specialist is a way to identify what kinds of food and habitat resources it relies on to survive. Generalists can eat a variety of foods and thrive in a range of habitats. Specialists, on the other hand, have a limited diet and stricter habitat requirements. (National Geographic Resource Library)

Appearance

While there are several different forms (sub-species) of Dark-eyed Junco in the US, the form known as the Oregon Dark-eyed Junco is our most common form. The adult male “Oregon” Dark-eyed Junco is easily identified by its all-dark head and brown back, pale bill, white belly and white outer-tail feathers. The white outer tail feathers flash distinctively in flight and while hopping on the ground.

The female and 1st year male “Oregon” Dark-eyed Juncos sport a more medium to light gray head, but otherwise look the same.

OTHER JUNCOS

Some of the other forms (sub-species) of Dark-eyed Junco that may appear from time-to-time in the Central Valley include the curious all gray with a white belly Slate-colored Junco or the reddish-backed Gray-headed Junco. In SE Arizona there is a completely different species called the Yellow-eyed Junco that looks like a Gray-headed, but with yellow eyes.

Previous posts from the Learn 100 Common Valley Birds series,

• Common Valley Phalaropes
• Pigeons and Doves
• Tree-creeping Birds
• LBBs – Little Brown Birds
• Coots and Gallinules

By Jim Gain

Post #4 in the Learn 100 Common Valley Birds series. (Species 8/100.)

Western Kingbirds are Common Summer Visitors to California’s Central Valley and are one of the earliest returning Neotropic migrants usually arriving from Mexico and Central America in mid to late March. Their sudden appearance along country road fence lines is a sure sign that Spring has arrived.

Adult Western Kingbirds are typically seen perching on fence wires where they sally out to snatch flying insects. They are monomorphic (males and females have similar appearance), recognized by their yellow belly, all pale-gray chest and throat and gray-brown back. They will frequently flash their white outer tailfeathers as they fly out from their perch.

Western Kingbirds belong to the Tyrant Flycatcher family (Tyrannidae) and are one of 7 kingbirds found in the US. Of those 7 species, only 2 are regularly found in the Central Valley. The other kingbird found regularly in the Central Valley (much rarer) is the Cassin’s Kingbird. Cassin’s Kingbird has white-tipped tail feathers instead of the white-edges. It also has a darker gray chest and head with a bold white chin. Check out the comparison images below.

Previous posts from the Learn 100 Common Valley Birds series,

• Common Valley Phalaropes
• Pigeons and Doves
• Tree-creeping Birds
• LBBs – Little Brown Birds
• Coots and Gallinules

By Jim Gain

Post #3 in the Learn 100 Common Valley Birds series. (Species 5, 6 and 7/100.)

Today’s post is another three-fer offering that includes the three owls that most Central Valley Visitors are likely to encounter in an urban setting; Great Horned Owl, Barn Owl and Western Screech-Owl. There are other possible owl species that one might come across in the grasslands and foothill woodlands away from town. One of those, the Burrowing Owl, will have its own future post and the others are considerably less likely to be observed.

GREAT HORNED OWL

Introduction

The Great Horned Owl is a Common Year-Round Resident in the valley. A large, powerful nocturnal predator, it is equally at home in any valley habitat taking a wide variety of prey.

Appearance

The Great Horned Owl is characterized by its ear tufts, white throat and barred brown tan and white body. Their hooting can be heard throughout the year mostly at night, but in the breeding season, may continue through the morning.

Distribution

A nighttime expedition to the riparian woodlands of any of the parks along the creeks and rivers that run through the Central Valley will likely result in an encounter with this nocturnal hunter. Careful springtime explorers may encounter a Great Horned Owl’s nest with the curious owlets peering out.

BARN OWL

Introduction

The Barn Owl (Tyto Alba) is a Common Year-Round Resident in the valley and is a bit smaller than the Great Horned Owl. It is the most widely distributed species of owl in the world and one of the most cosmopolitan (widespread) of all species of birds.

Appearance

Lanky, with a whitish face, chest, and belly, and buffy upperparts, this owl roosts in hidden, quiet places during the day.

Distribution

By night, they hunt on buoyant wingbeats in open fields and meadows. You can find them by listening for their eerie, raspy calls, quite unlike the hoots of other owls. Due to the large number of rodents they eat, farmers welcome the Barn Owl and often install nest boxes on their properties.

Cool Fact:

The Barn Owl has excellent low-light vision, and can easily find prey at night by sight. But its ability to locate prey by sound alone is the best of any animal that has ever been tested. It can catch mice in complete darkness in the lab, or hidden by vegetation or snow out in the real world.

WESTERN SCREECH-OWL

Introduction

The Western Screech-Owl (Megascops kennicottii) is a small owl native to North and Central America and is a Fairly Common Year-Round Resident in the Central Valley. It may be encountered in urban parks with mature trees or in riparian woodlands.

Western Screech-Owls nest in the cavities of large trees and typically lay three to five eggs in late March.

Appearance

The Western Screech-Owl is a pint-sized, cryptically patterned gray owl with fine streaks of black and white and short ear tufts.

Distribution

Found in a variety of wooded habitats, but favors riparian and deciduous areas. Can be found in urban areas and parks. Feeds mostly on small mammals, birds, and insects. Nests in cavities. Listen for its voice at night: a series of short whistled notes that accelerates at the end.

Previous posts from the Learn 100 Common Valley Birds series,

• Common Valley Phalaropes
• Pigeons and Doves
• Tree-creeping Birds
• LBBs – Little Brown Birds
• Coots and Gallinules