The 4 Falcons Found In California (Plus 3 Rare Ones)

California, a state recognized for its abundant biodiversity, is also home to an array of remarkable birds of prey, including a selection of awe-inspiring falcon species. From the rapid Peregrine Falcon, renowned as the world’s fastest animal, to the agile American Kestrel, the smallest falcon in North America, these birds of prey are a captivating sight for bird enthusiasts and curious observers alike.

In this comprehensive guide, we delve into the world of four common falcon species found in California – the American Kestrel, Peregrine Falcon, Prairie Falcon, and Merlin. We’ll also touch on the rare appearances of the Crested Caracara, Gyrfalcon, and the Eurasian Kestrel in the Golden State.

1. American Kestrel: The Petite Predator

The American Kestrel (Falco sparverius), the smallest falcon in North America, is a native species spread across the North and South American continents. Its vibrant plumage and unique hunting techniques make it a captivating sight in the wild.

Physical Characteristics

American Kestrels showcase a fascinating sexual dimorphism where females are not just larger, but also more vibrantly colored than males. Both genders have dark vertical stripes on their heads, an attribute that makes them easily identifiable.

In terms of size, the American Kestrel measures between 8.7 to 12.2 inches in length and weighs approximately 2.8 oz to 5.6 oz. Their wingspan ranges from 20–24 inches.

The males possess a blue-gray colored head with two black stripes on their face known as ‘mustaches.’ Their back feathers are reddish-brown, while their tails have black bands and white tips.

Females, on the other hand, have rust-colored heads with dark barring all around. They also have rusty red backs and tails with black bars that are more prominent than those of males.

Habitat and Diet

American Kestrels are year-round residents of California, with their population swelling from September to mid-March. They usually inhabit open areas without dense cover, as they prefer a clear view of their entire territory from a single perch. As opportunistic feeders, their diet ranges from insects and invertebrates to small mammals and other birds.

Conservation Status

The American Kestrel, despite being one of the most prevalent falcons in North America, is witnessing a steady decline in its population.

Estimates place the North American population at around 1.2 million pairs, similar to Central and South American populations, and a smaller estimate suggests 236,000 birds wintering in North America.

While there was a population increase in the 18th and 19th centuries due to deforestation for agriculture, which created ideal habitats for kestrels, the trend has reversed. The southeastern U.S. subspecies has suffered an 82% decline since 1940, largely due to the loss of longleaf pines, which were cleared for agricultural fields, resulting in a reduction in nest site availability.

However, despite these challenges, the IUCN Red List still classifies the American Kestrel as ‘least concern’.

In response to these issues, The Peregrine Fund launched the American Kestrel Partnership in 2012, creating an online platform for both citizen and professional scientists to contribute and consolidate data from kestrel nest box monitoring programs.

The data collected is used by researchers to understand the relationship between kestrel nesting parameters and environmental factors. This initiative also features a live video feed each breeding season from a nest box located at The Peregrine Fund’s campus in Boise, Idaho. These efforts aim to conserve the species through habitat preservation and raising public awareness about the importance of this beautiful bird.

2. Peregrine Falcon: The Speedy Skydiver

The Peregrine Falcon (Falco peregrinus), holding the record as the fastest bird in the world, is one of the most widespread raptors. Interestingly, these falcons are seen in urban areas, often nesting on tall buildings or bridges, becoming local celebrities in the process.

Physical Characteristics

With a body length that varies between 13 to 23 inches and a wingspan that extends from 29 to 47 inches, the Peregrine Falcon exhibits sexual dimorphism where the females are up to 30% larger than their male counterparts. This characteristic, quite common in raptors, is a key aspect of their biology that underlines the female’s role in hunting and protecting the nest.

The adult Peregrine Falcons have a unique coloration that sets them apart.

Their top side, including the back and wings, is bluish-black to slate grey with darker barring. In contrast, the bottom side ranges from white to rusty, marked with clean bands of dark brown or black.

The tail, long and narrow, is rounded at the tip, with a black terminal band and a white band preceding it. The falcon’s head and cheeks are marked by a black malar stripe, which is believed to serve the critical function of reducing glare from solar radiation. This feature’s thickness has been observed to correspond with the amount of solar radiation in the falcon’s environment, thus serving as a natural adaptation for enhanced vision.

Habitat and Diet

The Peregrine Falcon is known to inhabit various environments such as mountain ranges, river valleys, coastlines, and increasingly, cities.

When it comes to their diet, Peregrine Falcons are opportunistic predators and their food preferences vary greatly depending on the available prey in their region. Typically, they feed on medium-sized birds such as pigeons and doves, waterfowl, gamebirds, songbirds, parrots, seabirds, and waders. In urban areas, they primarily feed on a variety of pigeons, while coastal populations focus on seabirds.

All in all, they have a diverse prey base, with a documented record of preying on over 450 different bird species.

Conservation Status

The Peregrine Falcon, once endangered during the 1950s to 19790s due to the use of pesticides that led to thinner eggshells and reduced hatching rates, has seen a significant recovery.

Efforts to revive the species included breeding in captivity and releasing them post-acclimatization. These recovery efforts, coupled with the banning of harmful pesticides, have been successful globally, leading to the removal of the peregrine falcon from the U.S. Endangered Species list.

Despite these positive strides, the Peregrine Falcon continues to face challenges. Illegal poaching of eggs and chicks remains a concern, leading to the common practice of keeping nest locations confidential.

3. Prairie Falcon: The Grassland Guardian

The Prairie Falcon (Falco mexicanus) is a medium-sized raptor native to the arid environments of the western United States. Despite its smaller size compared to the Peregrine Falcon, it is an equally adept hunter.

Physical Characteristics

The adult male prairie falcons typically measure around 15 inches in length and weigh approximately 1.1 to 1.4 lbs.

Their female counterparts are larger, measuring about 17.7 inches and weighing between 1.7 to 2.1 lbs. In fact, a large female can be nearly twice the size of a small male, boasting a wingspan reaching up to 3.5 feet, which enables them to hunt significantly larger prey.

Their plumage is predominantly warm gray-brown, often referred to as “sandy”. The darkest part of their upper side is the primary wing feathers, while the rump and tail, especially the outer tail feathers, are the lightest.

Their heads feature a narrow “mustache” mark akin to a peregrine falcon’s, as well as a white line over the eye. A key distinguishing feature is their black axillars (“wingpits”) and underwing coverts, except along the leading edge of the wing, creating an effect of “struts” from the body along each wing.

Habitat and Diet

The prairie falcon is a bird that thrives in open country, particularly in arid conditions.

During the summer, their habitat ranges from alpine tundra to shortgrass prairie and high desert. However, in winter, they become more widespread, extending to low deserts and even occasionally venturing into towns.

Their breeding grounds span from southern Manitoba, Saskatchewan, Alberta, and south-central British Columbia, south through the western United States — roughly between the eastern edge of the Mountain Time Zone and the Cascade Mountains, as well as the Central Valley of California — to the Mexican states of Baja California, Durango, and northern San Luis Potosí.

Unlike other North American falcons, prairie falcons are less migratory. Still, during winter, they withdraw somewhat from the northernmost and highest-elevation parts of their breeding range, spreading west to the deserts and Pacific coast of California, and south to Baja California Sur, Jalisco, and Hidalgo. This broad distribution allows the Prairie Falcon to adapt to different climates and environments.

Prairie falcons primarily feed on small mammals, especially during the summer, and small to medium-sized birds caught in flight. However, as opportunistic predators, they will occasionally prey on larger birds.

Common mammalian prey for prairie falcons include squirrels, ground squirrels, prairie dogs, chipmunks, gophers, and various species of rabbits. They also sometimes prey on reptiles. Bird prey commonly includes sparrows, starlings, grackles, doves, quail, meadowlarks, pigeons, coots, teal, and mallards — virtually any bird of up to approximately the falcon’s own size and occasionally significantly larger.

However, the reproductive success of the prairie falcon hinges on the availability of smaller prey that they can carry during the nesting season.

Conservation Status

The IUCN has designated the Prairie Falcons as ‘least concern’ due to its expansive range and seemingly growing population.

Having said that, there have been some regional decreases in places like Texas, California, British Columbia, and Alberta where grasslands are being repurposed for agriculture, urban development, and other human activities.

These reductions could potentially lead to challenges in finding partners or suitable living conditions for these birds. To combat this, conservation strategies are centered around maintaining open grasslands, controlling invasive species, and guaranteeing the provision of appropriate nesting locations.

4. Merlin: The Small But Fierce Falcon

The Merlin (Falco columbarius) is a small but fierce falcon known for its agility and speed. It has several subspecies living across North America, Europe, and Asia, each with varying degrees of coloration depending on their geographic location.

Physical Characteristics

The Merlin Falcon is a robust bird relative to other small falcons, measuring 9.4–13.0 inches in length with a wingspan ranging from 19.7–28.7 inches.

There’s a noticeable difference in weight between males and females; males typically weigh around 5.8 ounces, while females average around 8.1 ounces. However, weight can significantly vary throughout their range and over the course of a year, particularly in migratory populations.

Merlins exhibit distinct coloration based on sex and age. Males have a blue-grey back, varying from nearly black to silver-grey across different subspecies, with buff- to orange-tinted underparts streaked with black to reddish-brown. In contrast, females and immature merlins are brownish-grey to dark brown above, with whitish buff spotted with brown below.

The flight feathers, or remiges, are blackish, and the tail usually features 3–4 wide blackish bands.

All merlins have a black tail tip with a narrow white band at the very end. Their eyes and beak are dark, with the beak featuring a yellow cere, and their feet are yellow with black claws.

Despite some color variations among different regions and subspecies, certain characteristics remain consistent. For example, light American male merlins may resemble the American kestrel but can be distinguished by their grey back and tail. Similarly, light European males have primarily brown wings, distinguishing them from kestrels. These unique traits make the merlin falcon a fascinating species in the world of raptors.

Habitat and Diet

Merlins inhabit a variety of open terrains including willow or birch scrub, shrubland, taiga forests, parks, grasslands such as steppes and prairies, or moorland.

They can be found from sea level to the treeline, generally preferring a mix of low and medium-height vegetation with some trees, while avoiding dense forests and treeless arid regions.

These falcons are largely migratory, with Northern European birds moving to southern Europe and North Africa, and North American populations moving to the southern United States and northern South America. During winter, they may just move to coasts and lowlands in milder maritime parts of their breeding range.

Merlins are highly skilled hunters that rely on speed and agility to catch prey. They often hunt by flying fast and low, typically less than 3.3 feet above the ground, using trees and large shrubs for surprise attacks. Nevertheless, most prey is captured in the air, as they “tail-chase” startled birds.

The merlin’s diet primarily consists of smallish birds weighing 0.35–1.41 ounces during the breeding season. However, they are opportunistic predators and will also prey on larger birds, insects, small mammals, reptiles, and amphibians, especially outside the breeding season. They are known for their fearlessness and will readily attack anything that moves conspicuously.

Threats to merlins come mainly from corvids preying on eggs and nestlings, and larger raptors preying on adults. Despite this, carnivorous birds tend to avoid merlins due to their aggressiveness and agility. Their tenacity in driving larger raptors away from their territory is such a distinct trait that it can be used for identification and detection, often revealing their presence as they vigorously harass another raptor.

Conservation Status

The Merlin Falcon, due to its widespread range and substantial population, is classified as a species of ‘Least Concern’ by the International Union for Conservation of Nature (IUCN).

The most significant long-term threat to this species is habitat destruction, particularly in their breeding areas. Ground-nesting populations in moorland, which prefer tall heather, are vulnerable to overmanagement through burning, disrupting the habitat mosaic.

In North America, there’s evidence suggesting that the Merlin Falcon’s range may have shifted northwards over time, likely due to changing land use and global warming.

Accidental collisions with man-made objects account for a significant portion of premature Merlin deaths. Furthermore, in the mid-20th century, pesticides led to declines in the species, particularly in Canada, due to eggshell thinning and immune system compromise. Restrictions on these chemicals have since led to a rebound in their population. In general, while temporary declines may occur in certain regions, global Merlin populations appear stable, often increasing again eventually.

5. Rare Sightings: Crested Caracara, Gyrfalcon, and Eurasian Kestrel

Apart from the four common falcons found in California, the state occasionally witnesses the rare presence of the Crested Caracara, Gyrfalcon, and the Eurasian Kestrel. Although these sightings are sporadic, they add an exciting dimension to the state’s birding scene.

  • The Crested Caracara, also known (incorrectly) as ‘The Mexican Eagle’, is a rare sight in California. This large, long-legged raptor is commonly associated with open habitats and is often observed walking on the ground or perching prominently on fence posts or telephone poles. Notable for its dark cap, pale neck, and strikingly patterned underparts. This bird typically inhabits open or semi-open landscapes and avoids high-altitude and dense humid forests. While its presence has been reported sporadically in areas as far north as San Francisco and near Crescent City in 2012, these instances don’t establish it as a regular species in California
  • The Gyrfalcon, the largest of the falcon species, is a truly exceptional sighting in California. Known for their powerful flight and preference for arctic climates, these birds are seldom seen outside of the far northern regions of North America. However, there have been reports of a Gyrfalcon sighting in Warren, New Jersey, indicating that these magnificent birds occasionally venture further south, including California as well.
  • The Eurasian Kestrel is another falcon species that could potentially be spotted in California. As its name suggests, this bird is native to Europe and Asia but has been known to wander far from its usual range. While such an occurrence would be extremely rare, the bird’s distinctive hovering flight and pointed wings would make it a memorable sight for any birdwatcher.
Gyrfalcon

6. Falcons and Falconry

Falcons have been highly regarded in the world of falconry for centuries. Their swift flight, keen eyesight, and hunting prowess make them a popular choice for falconers.

In California, Peregrine Falcons and Prairie Falcons are among the most sought-after species for this ancient sport. In fact, California is home to the largest state falconry organization in the United States – the California Hawking Club, established in 1971.

Falconry is considered a form of art and requires extensive knowledge and skill to train and handle these birds of prey.

It involves using trained falcons to hunt wild game for food or sport. Along with being an important aspect of cultural heritage, falconry also contributes to conservation efforts by promoting the preservation of raptors and their habitats.

7. Falcons in Urban Areas

Some falcon species, such as the Peregrine Falcon and the Merlin, have started to adapt to urban environments. They have learned to nest on tall buildings and bridges, and hunt pigeons and other city-dwelling birds.

8. Falcons and Conservation

Falcons in California, like many other bird species, face numerous threats, including habitat loss and pesticide exposure. Conservation efforts, such as habitat restoration, regulation of harmful chemicals, and public education, are crucial for their survival.

9. Spotting Falcons in California

California offers numerous birding sites where one can spot these remarkable falcons.

Be it the serene Yosemite National Park, the bustling Golden Gate National Recreation Area, or the tranquil Morro Bay, each location provides unique opportunities to observe and appreciate these agile hunters in their natural habitats.

The falcons of California are a testament to the state’s rich biodiversity. These majestic birds, each with their unique traits and behaviors, contribute significantly to the ecosystem. Understanding their habits and the threats they face is crucial for their conservation. As we continue to expand our knowledge, we can work towards ensuring a thriving future for these extraordinary species.

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