Thursday, December 27, 2007

What's in a towhee?

Coming into work today, I heard the distinctive, loud "chink" call of a California Towhee (pictured) from a yard behind the Habitat Authority office (downtown Whittier, near Washington and Mar Vista).

Towhees (all 3 species in California) are rarely found in urban habitats, though both the California and Spotted towhees are resident in the hilly neighborhoods around the Puente Hills. In the Hollywood area where I used to live, I almost never saw them south of Sunset Blvd., though small numbers are resident in an isolated population in the Baldwin Hills (north of LAX). In the San Gabriel Valley, where I grew up, I never saw one in my backyard, though they were resident at the overgrown grounds of an old mansion a few blocks away, and along the landscaped flood control of Eaton Wash.

All of our animal species exhibit some degree of tolerance to urbanization, from birds like Band-tailed Pigeons and crows that seem to favor built/planted areas, to those like the California Quail and the gnatcatchers which simply can't make it away from native vegetation. I think of the California Towhee as sort of intermediate in terms of sensitivity, and one that may respond very quickly to native plantings in backyards.

Still, I was surprised that this individual made it so far south into the "flats" of Whittier. I wonder if they make it south of Whittier Blvd., and if so, where?

Thursday, November 29, 2007

Golden-crowned Kinglets - the invasion continues!

This fall has proven to be one of the most dramatic ones in recent years for several montane (mountain-dwelling) species in the lowlands of California.

Every few years, individuals of species normally found in the high mountains drift down to the lowlands, mainly living in planted pines for a few months before disappearing in early spring. Some, like the Mountain Chickadee, irrupt nearly every year, and are probably present more winters than they're absent (I had a small flock at the edge of the hills near Schabarum Park a couple weeks ago). Others, like the Golden-crowned Kinglet, are on a longer cycle, here in the lowlands every 3-5 years and totally absent otherwise.

So it was a nice surprise to find two of these kinglets this morning at The Park in La Habra Heights (along Hacienda Blvd. just north of East Rd.). Their calls are very faint, but distinctive once learned - a three-note "see-see-see", invariably coming from pines.

Based on sublte differences in calls and plumage, these montane invaders often represent Great Basin or Rocky Mountain forms (rather than nearby Sierra Nevada/Transverse Range ones) of the species involved, indicating that their irruptions are part of a larger, region-wide phenomenon when they occur; not just local birds moving down from Mt. Baldy or Lake Arrowhead. Indeed, one of the best places to see montane species like Red Crossbill and Red-breasted Nuthatch during these "invasion winters" is far out in the Mojave Desert, where ranchyards planted with Aleppo pines are the only trees for miles around. Here in the coastal lowlands, they often occur in Canary Island pines, which became hugely popular as street trees in the L.A. area in the 1960s.

Wednesday, November 21, 2007

Another weasel shot

Jeff Allison just forwarded me this photo of a weasel carrying a rodent at his house (in La Habra Heights). I wonder how common these things really are?

Thursday, November 1, 2007

Eagle over Sycamore!

I was surprised to see a Golden Eagle soaring about midway up Sycamore Cyn. today around noon. Beautiful bird (immature, with a white base to the tail and white "flashes" in the wings), which really dwarfed the ravens that were harrassing it.

Have folks seen one around so far this fall? It's a semi-regular spot for them in late fall, probably owing to the extensive grassland up there and behind Rose Hills Cemetery. I wonder if they drift east along the corridor to forage at Powder Canyon or elsewhere.

Thursday, October 25, 2007

Raptor migration in the hills

Yesterday while doing fieldwork in La Habra Heights, I was surprised to see a young Northern Harrier sail overhead. These hawks are uncommon migrants in the hills, and a handful may winter. They require large blocks of undeveloped grassland and low scrub, and not surprisingly, have very little habitat left in the Los Angeles Area. Ten years ago, we found them nesting in just one spot in the Puente-Chino Hills - a single pair in the wet grasslands of upper Tonner Canyon, visible from Grand Ave.

Wintering areas are now almost as scarce, and folks should let me know if they run across any this winter. Males are pale grayish above and clear white below, while females and especially first-year birds are brownish below. Both sexes have bright white rumps, which may be seen as they tilt back and forth.

In the same area of La Habra Heights, I also observed an Osprey circling, and then later in the afternoon, another first-year harrier over Turnbull Canyon. Late fall (October) is when hawk migration peaks through our area, and folks may be seeing increased numbers of raptors these days. They aren't being displaced by fires, but are just following well-worn pathways through the sky, heading southeast into Mexico.

Tuesday, October 9, 2007

Butterflies of the Puente Hills

I recently received an inquiry about butterflies in the hills, and want to summarize what we know.

First off, the hills appear to represent an important reserve for native butterfly populations in the L.A. Basin, with 40 species confirmed and a handful of potentially-occurring ones. Diversity of species, not surprisingly, is highest where there is an intersection of major habitat types together, such as willow thickets next to oak woodland next to cactus scrub. Numbers of individuals are dependent on the availability of flowering plants, and some specialized species fly only where their foodplant is in flower.

Not much is known about the distance butterflies can move. A few engage in long-distance migrations, most famously the monarch, but others probably spend most of their lives around the same small patch of native scrub, generation after generation. These specialists are of great concern to conservationists, since their presence often indicates a particularly robust ecosystem.

Many species in the L.A. area fly year-round, but if there's a season when the highest numbers of species and individuals are flying, it's probably late spring (April through June), corresponding to wildflower blooming and warming nights. However, several species emerge through autumn into early winter, nectaring on fall-blooming buckwheat.

In our area, places that attract butterflies include patches of coast buckwheat and mulefat shrubs (only when in bloom), and damp spots along canyon bottoms, particularly if they're exposed to sun. Butterflies will often come to muddy spots in roads to ingest minerals from the soil (most dramatically in the tropics, but also locally).

Most popular gardening books encourage people to plant butterfly-attracting plants to bring butterflies to their gardens, especially "butterfly plant" (a generic term for several species). Several of these are noxious pests (e.g., lantana), which should not be planted anywhere near the open space of the hills. It is better to use native plants (watch for sales at places like Rancho Santa Ana Botanical Gardens in Claremont, or at the L.A. Co. Arboretum in Arcadia), or if your neighbors will stand it, let a portion of your backyard turn "wild" and see what comes in. Just tell them the butterflies made you do it.

A couple websites:

Friday, October 5, 2007

Restoration monitoring preview

One of the goals of all the scrub, woodland and grassland restoration in the Puente Hills is to provide habitat for declining wildlife species. Yesterday, I stopped briefly at the Harbor Blvd. undercrossing to look for scarce lizards in the afternoon heat. While I didn't find these, I did flush a Rufous-crowned Sparrow (pictured) foraging in the native bunchgrasses that were planted as landscaping around the undercrossing (west side of Harbor Blvd.). A large population of this sparrow is found in the scrubby grassland just east of Harbor Blvd. on the Aera property and adjacent to the Shea Homes development.

This is an inconspicuous species typically detected by voice, and is told from other local sparrows (incl. imm. White-crowned and adult Chipping) by its unmarked wings (i.e., no white wingbars), black "mustache" stripe and white eyering. It has two calls, one a high thin "sseeet", and the other a rough "deer-deer-deer", in addition to its song which resembles a weak House Wren.

In the next year, we hope to initiate biomonitoring all the restoration areas in the hills (there are over a dozen) and find other sensitive species like this sparrow using them.

Wednesday, September 26, 2007

New insect: spreadwing sp.

While on a site visit to Sycamore Canyon yesterday, I observed several spreadwing damselflies along the stream (photo). They were a grayish lavender color, and appeared to be either the California spreadwing (Archilestes californica) or the great spreadwing (A. grandis).

Thanks to the recent publication of illustrated field guides, dragonflies and damselflies ("odonates" collectively) have joined butterflies as a group of insects that may be identified readily through binoculars. Consequently, we are quickly gaining a much clearer picture of the status and distribution of these varied creatures throughout the state (and the U.S.).

Only a handful of odonate species have been identified in the Puente Hills, and this genus, an autumn emerger, may have been missed by previous surveyors working in the spring and summer.

Monday, September 17, 2007

Long-eared Owl, Tonner Canyon, and the power of Google

While doing a websearch this morning for birds of the Puente Hills, I came across a fascinating tidbit buried in a 1929 issue of the journal The Condor ("Some results of bird banding in 1928" by John McB. Robertson):

"Nestling Long-eared Owl no. 543281 banded April 10, 1928, at Rancho de los Tres Hermanos, in the Puente Hills of southeastern Los Angeles County, was taken four miles from Lancaster, California, between December 29, 1928 and January 3, 1929, a distance of about fifty miles."

Old journal articles were notoriously vaguely-worded, and as this is no exception, I missed this reference entirely in previous literature searches of birds of the Puente-Chino Hills. This note is significant for several reasons. First, it provides evidence that this scarce owl (a California Bird Species of Special Concern, pictured here) once occurred and even nested in the Puente Hills. This species, once common in ranches and riverbottoms throughout the region, is now nearly extirpated from all of southern California, with only a handful of nesting pairs known from interior valleys, remote mountain ranges, and desert oases.

Also, it illustrates the importance of the hills as a nesting area for raptors that may disperse widely for the winter and return to breed in the spring. The article also mentions a Red-tailed nestling from Carbon Canyon found (in a coyote trap!) in Madera County in the Central Valley (the fact that both these birds flew north, rather than south, for the winter is also interesting).

Finally, it suggests that scarce species like the Long-eared Owl may yet be holding out in some of the more remote canyons and properties of the Puente Hills, awaiting discovery. This ranchland is still there, visible from Grand Ave. as it crosses from Diamond Bar into Chino Hills. As the surrounding area developed in the past 80 years, maybe the owls left at some point - but maybe they've been there all along...

Thursday, September 13, 2007

Trouble for Cactus Wren (and cactus?)

The Puente Hills supports one of the largest coastal-slope populations of the Cactus Wren, a large, mockingbird-like member of the wren family that is completely dependent on large clumps of cactus for nesting and foraging.

Coastal populations are restricted to southern California (Ventura Co.) south into Baja Calif., Mexico, and are geographically and genetically isolated from birds in the desert.

When I was surveying the Puente-Chino Hills for birds in the late 1990s, they seemed to be more widespread, but now are gone from many of their former haunts. I've been revisting cactus patches over the past few weeks, and have either found many fewer or have found them gone entirely.

The cactus patches themselves also appear to be in trouble - the pads withered, with large dead areas within the patches. A colleague of mine has noticed the same thing in southern Orange Co. - sickly looking cactus patches devoid of Cactus Wrens. This is especially troubling because these patches hold several distinctive plant and animal species (not just Cactus Wrens), and can serve as refugia when fires whip through an area, protecting the soil.

Today, I checked the extensive cactus on the south-facing slope just south of Sycamore Canyon above Hellman Park in Whittier, basically the top of Rideout St. I didn't hear a single one. I'm working on a chart of extant populations, but it looks grim - Sycamore Canyon seems to have most of the birds, with small numbers in upper Turnbull Cyn. (north of T.C. Rd.), along Colima Rd. (in 2002) and just east of Hacienda Dr. near Skyline Trail. Birds appear to be gone from Schabaurum Park and possibly from the slopes above Whittier.

Does anyone know of additional populations, and if so, where??

Friday, September 7, 2007

Have you seen me?

This is a Nutmeg Mannakin, a goldfinch-sized bird from southeast Asia that has become established in parts of the Los Angeles area in the past 15 years. They are most often found in wet, weedy patches, but will also visit bird feeders. I had one fly overhead (calling) at the head of Arroyo Pescadero just west of Colima yesterday, and today, I saw one perched just upstream of Murphy Ranch Park near the Whittier/La Habra Heights border.

New plant species for hills: Scrub oak

Not much of a name, but there you have it. The scrub oak (Quercus berberidifolia) is found in chaparral from Humboldt Co. into northern Baja Calif., Mexico (like many chaparral plants and animals). In the Los Angeles area, it is generally found in the foothills of the San Gabriel Mtns. and in the Santa Monicas where other chaparral species are present, such as chamise, mountain-mahogany and Ceanothus. It is scarce or absent at lower elevations and along the immediate coast such as Palos Verdes, the Baldwin Hills and the Montebello/Repetto Hills, where coastal sage scrub - dominated by sages, sagebrush and buckwheat - tends to replace the higher, thicker chaparral.

In the Puente Hills, typical chaparral occurs only east of Powder Canyon, from the open space south of Rowland Heights east and north into Diamond Bar. West of here, tall shrubland tends to be dominated by sumacs and toyon, and has been called "sumac scrub". It is possible that the scrub oak and other chaparral species were burned out of the Whittier Hills over the years, or were eliminated by early brush clearance and grazing. Or, there exists a mysterious ecological barrier that has prevented their expansion west.

While conducting fieldwork here in 1997, I noticed a couple scraggly-looking scrub oaks along the Edison powerline right-of-way west of Colima Rd., growing between a steep slope and a chain-link fence, and thus protected from fire and brush-clearance. The plants were still there when I collected a sample this week (photographed), and may be the only ones in the western Puente Hills.

Tuesday, August 28, 2007

New bird species for hills: Common Ground-Dove

A male (see photo) was singing this morning at the Powder Canyon trailhead. This bird is a very localized resident in southern California, maintaining a small population in our area along the lower San Gabriel River. Has anyone had this bird at their feeder? They are tiny doves, just a little bigger than sparrows.

Side-blotched Lizard

A tour of the old Nike missile sites along the ridgeline east of Harbor Blvd. today produced a male and female side-blotched lizard around the concrete debris at the site. The surrounding vegetation is extensive, open grassland (heavily grazed) with patches of Coast Goldenbush. A recent (2002 USGS reptile study of the Puente-Chino Hills found this lizard only east of Powder Canyon. This is surprising, since I've seen them along the San Gabriel River in Whittier Narrows, along the Arroyo Seco in northwest Pasadena, and at tiny habitat remnants like the Ballona Wetlands dunes in Playa del Rey.

Though they were historically much more common in the L.A. basin, they seem to like sandy soil with barren patches, which is now a scarce commodity. Most of these sites have been developed or have been replaced by different vegetation, and the animals that maintained this habitat (cattle, sheep, jackrabbits) are gone. For example, they were collected at Griffith Park decades ago, but have apparently disappeared from there since, as the vegetation there has matured from low, open buckwheat scrub to high sumac and Ceanothus chaparral.

This lizard is very poorly depicted in illustrations, including the Peterson guide to reptiles and amphibians - I think it's more attractive than our "normal" lizard, the western fence lizard, locally called the "bluebelly" for the blue underparts of the males. Side-blotched lizards are best identified by the gular folds (= loose skin) around the neck, and by the distinctive orange checkerboard pattern on the upperparts. Mature males will show black patches behind the front legs, but on many individuals these are absent or hard to see.

Monday, August 27, 2007

Ford property sightings

While assessing the impact of the recent fire, Andrea Gullo and I visited the "Ford property", a parcel owned by the Habitat Authority at the head of Turnbull Canyon, just north of Turnbull Cyn. Rd.

Two sensitive species were present, a Cactus Wren giving a single "chert" call from the cactus on the slope below (to the west), and a coastal western whiptail moving through the leaf litter at the edge of the property's driveway. This lizard is apparently localized in the hills. I've posted a (poor) photo of the whiptail here.

Wednesday, August 22, 2007

New mammal for Puente Hills: Long-tailed weasel

The same yard that brought us the bobcat photo below produced a long-tailed weasel in February 2007, photographed here carrying what appears to be a Norway rat.

The weasel was listed as "potentially occurring" in the Resource Management Plan, and is probably an uncommon resident throughout the Puente-Chino Hills. They are somewhat like ground-squirrels, but are much slimmer, with distinctive dark facial markings. Weasels are most often seen alone, in brushy areas near water (when they are seen at all). They live in burrows excavated by other animals, and are most active at night.

Anyone else ever see a weasel in the hills?

Turnbull Canyon fire

Approximately 80 acres of open space burned yesterday in the upper Turnbull Canyon watershed, ignited by a car that went over the side of the road near the midpoint of Turnbull Cyn. Rd. (the driver escaped with apparently minor injuries). The fire burned a bit of the downhill (northern) slope below the road, but quickly raced uphill to the south and east before being contained at the ridgeline. If you're familiar with hiking or riding in this area, the burn area is mainly south of Turnbull Cyn. Rd., roughly bounded by the Schabarum Trail on the east and by fireroads/trails on the west and south, and includes a portion of Workman Hill.

This fire occurred in the wide portion of the corridor, in an area that has seen frequent fire over the years. Thus, it should not appreciably affect the movement of animals through the hills. As with all small fires, most animals flee the area briefly during the burn, or retreat to burrows, emerging only hours after the flames subside (only the top few millimeters of soil are burned). Plants will start resprouting almost immediately.

Unfortunately, frequent fires, as have occurred here, have resulted in the degradation of the soil microflora over recent decades. Extensive fields of non-native black mustard and thistle - and dense stands of laurel sumac shrubs - attest to a history of disturbance, both from grazing and fire. Still, the upper Turnbull watershed is still very diverse in terms of habitat types, with oak woodland, sumac-elderberry scrub, coastal sage scrub and native grassland occurring in patches of various sizes. Several of these patches were coded as "high quality habitat" by the Resource Management Plan (Fig. 5), a designation that was based on the dominance of native plant species.

Two populations of the rare Catalina Mariposa-Lily and one population of the rare Plummer's Mariposa-Lily (per Fig. 10A) were detected during recent surveys within the area affected by the fire; fieldwork this spring is needed to assess their current status. Fortunately, the unique vernal pool area just to the south (upper Worsham Canyon watershed) was unaffected, and neither were the large prickly-pear/buckwheat patches on south-facing slopes north of Turnbull Cyn. Rd., which are important for many rare plant and animal species.

We will be monitoring the recovery of this area in upcoming years.

Monday, August 20, 2007

Two new insect species for hills: Western pygmy blue and giant darner

Note: by "new", I mean unlisted by LSA and Associates in their Resource Management Plan for the Puente Hills (2007), which included a comprehensive species list of observed and potentially-present species.

Several western pygmy blue butterflies were flitting around their preferred foodplant, Australian saltbush, on the former Unocal property east of Hacienda Blvd. on 14 Aug. 2007. This is a widespread native species closely tied to weedy chenopods (saltbushes and relatives) that is probably fairly common in the hills.

A single giant darner was hunting in a disced/plowed border of one of the restoration sites in the same area today. It was nearly twice as large as the numerous gliders in the area, and showed the long, distinctively drooped abdomen. Usually found along streams, they should be looked for along Arroyo San Miguel and elsewhere.

New bird species for hills: Black Swift

Two Black Swifts cruised low over my head this morning as I was touring one of our restoration sites near Skyline Trail west of Hacienda Blvd. They were in a mixed flock that included other swifts (White-throated and Vaux's), as well as Cliff and Violet-green swallows.

The Black Swift is an uncommon and irregular transient throughout southern California, typically seen with other swifts and swallows in late spring (esp. May) and fall. They are very localized nesters in our area, with Big Santa Anita Cyn. being one of the traditional sites. They nest on the misty, mossy rock walls behind waterfalls.

Sunday, August 19, 2007

Bobcat, La Habra Hts.

A bobcat was observed and photographed on the morning of Aug. 15 near the intersection of Citron Rd. and Reposado Dr. in La Habra Heights. It was carrying a squirrel, possibly an California ground-squirrel (right).

The bobcat is an uncommon resident of the Puente Hills, occurring in a wide variety of habitats. They are active day and night, and are often seen walking along roads and trails, or stalking rodents on grassy hillsides. Like mule deer (and unlike coyotes), they rarely occur more than about a half-mile from large patches of open space. (Additionally, I observed a bobcat on Aug. 14 on Habitat Authority land east of Colima Rd.).


Welcome to Puente HIlls Nature!

Daniel S. Cooper
Ecologist, Puente Hills Landfill Native Habitat Preservation Authority
Whittier, CA