The Lost Populations

   Everybody knows that California condors once were found regularly north through Oregon, and at least occasionally to British Columbia, Canada. There have been different opinions about what those birds were doing up north. In his 1953 monograph, Carl Koford speculated that any condor north of San Francisco Bay was a wanderer from the south, probably up there looking for food. As far back as the early 1970s, I felt I had put together a pretty good case that condors had to be resident somewhere north of central California, and I published a paper to that effect (Wilbur, S. R. 1973. The California condor in the Pacific Northwest. Auk 90(1):196-198). In the years since, I've added more to the evidence. Below, I've reproduced Chapter 26 of my book "Nine Feet from Tip to Tip: the California Condor through History." If you read it, I suspect you will come away with the impression that my "various ruminations" on the subject, resulting from "digging into old notes, oral histories, family diaries, Indian lore, etc.," (as one person recently described it) have actually produced rather compelling evidence that condors existed as breeding birds to far northern California at least, and probably into Oregon.

[The following was originally published as a chapter in: "Nine Feet from Tip to Tip: the California Condor through History." (Gresham, Oregon: Symbios Books, 2012). If you would like a free copy (PDF) of the entire book, send me an e-mail.]

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   As noted in Chapter 15 [of "Nine Feet"], there were pronouncements as early as 1880 that condors were becoming rarer. The statements were more intuitive than factual,  because no one had knowledge of the entire range of the species. The most authoritative opinions were still based on changes observed in local situations. Still, when in the 1940s Carl Koford made the first species-wide analysis of condor populations, he concluded that condors had become rare in much of their range before 1910. He felt they were “extinct or very rare” in all areas north of San Francisco by 1890; in the central Coast Ranges by 1900; and south of Los Angeles before 1910. While he thought there might have been some increase in numbers after 1930 in the uplands around the southern San Joaquin Valley, he suspected this could have been due to changing foraging patterns, rather than changes in population size. The only areas where he felt confident that “the incidence of condors has remained about the same since the 1880s” were central Ventura County and northern Santa Barbara County [1].

   Koford identified various factors that were known, or suspected, to have killed condors [2], a list essentially the same as given in Chapter 25. In general - except for the area north of San Francisco Bay - he did not try to rank their individual impacts nor did he try to explain why condors had disappeared from the various regions. Below, I look at each region to see if Koford's unasked questions can be answered.

 

NORTH OF SAN FRANCISCO

    Carl Koford speculated that the total loss of condors north of the San Francisco Bay area occurred  - at least, in large part - because condors had never been resident in that vast area. He conceded that "the occurrence and disappearance of condors along the Columbia River (in Oregon and adjacent Washington) cannot be satisfactorily explained on the basis of available facts," but he thought all condor records north of San Francisco had been of non-breeding birds that periodically or irregularly wandered out of their usual range. He believed that as condors became rarer to the south, there were no longer birds to travel north [3].

   Early in my condor research, I proposed that condors in the Northwest were not merely wanderers, but were resident at least as far north as the Columbia River between Washington and Oregon [4]. I discussed my reasoning with Koford, but he remained convinced there had been no resident condors north of San Francisco Bay [5]. His main objections remained that there was not enough supporting evidence of continuous occupancy of the region from prehistoric to recent times, and that no one had discovered nesting north of Monterey County. He continued to support his earlier hypothesis that condors flew north in search of  food, either in times of food scarcity in the south or because there was some particularly attractive source in the north.

 Prehistoric and Pre-Caucasian Records

    The record is complicated somewhat by uncertainty as to whether or not there was any break between the occupancy of prehistoric and modern California condors in the early West (see Introduction and Chapter 1). Gymnogyps bones have been recovered from Samwel Cave and Potter Cave in Shasta County, California, associated with materials carbon-dated at around 15,000 to 20,000 years before present  [6]. At The Dalles, Wasco County, Oregon, bones from at least 22 different condors have been excavated, most of them from strata dated at 7,500 to 8,500 years old, with a few in older and a few in younger deposits [7]. A condor bone found on Pender Island, British Columbia, Canada, is about 2,900 years old [8]. These few records do not prove continuous occupancy, but they do show a long tenure.

    Native American records of condors were reviewed in Chapter 2. They show a strong connection between Indians and condors throughout the Sacramento Valley and northern Coast Ranges; a weak record in western Oregon (but perhaps due to lack of a deep oral history); no ties in Washington away from the Columbia River [9]; and none in British Columbia [10].

 Records by Europeans:  Oregon-Washington-British Columbia.

     Chapter 5 has most of the records of condors in Oregon and adjacent parts of Washington. I can add a few later observations to the Oregon narrative. James Clyman reported condors in the Willamette Valley 1844-1845 [11]. Roselle Putnam, a settler at Yoncalla, Douglas County, saw condors around 1851-1852 (no date or numbers given), and saw one dead condor in that area [12]. A condor was rumored to have been killed on the southern Oregon coast ca 1890 [13]. There are several records of 2-4 condors near Drain, Douglas County, in July 1903 and March 1904 [14]. “Several well-informed woodsmen described accurately” condors in southwest Oregon in the early 1900s [15].

    In Washington State, in addition to the records cited in Chapter 5, one condor was tentatively identified near Fort Vancouver in January 1854 [16]. A September 1897 sighting of a condor near Coulee City, Washington, was made by someone who had seen condors in California [17]. There are no other later records for Washington. There are several sightings from southwestern British Columbia between 1860 and 1890. None of them are particularly well documented, but all were within about 20 miles of one another, and only about 25 miles from where the condor bone was found on Pender Island [18]. J. K. Lord, who was in British Columbia 1858 to 1862, reported condors at the “mouth of Frasar River,” but there is no indication this was his own observation [19].  John Fannin wrote that “in September 1880, I saw two of these birds at Burrard Inlet;” he suspected they were “accidental visitants” [20]. Samuel Rhoads visited British Columbia in 1892. He did not see condors, but learned from long-time Lulu Island postmaster William London that they “used to be common” in the area, the last seen on Lulu Island “three or four years ago” [21].

 Records by Europeans: Northern California

     To 1850. In extreme northwestern California near the present town of Klamath, Humboldt County, Jedediah Smith in May 1828 recorded “large and small buzards [sic]” [22]. As he also listed “Crows…Ravens, several kinds of hawks, (and) Eagles,” it seems likely he saw condors. Between July 1840 and September 1841, Russian naturalist Ilya Voznesenskii collected a number of condors and (from the Indians) condor artifacts in the Coast Ranges and Sacramento Valley. There is only one certain date and place: May 1841, when Voznesenskii was in the Russian River area of Sonoma or Mendocino counties [23].

   The Wilkes Expedition traveled south through the Sacramento Valley in October 1841. They recorded several condors in the hills between Mt. Shasta and present-day Redding on 5 October; and saw “numbers” of them in the Valley at about the latitude of Red Bluff on 13 October [24]. Charles Pickering, one of the expedition naturalists, described a condor in immature plumage, when the party was in the vicinity of the Sutter Buttes [25].

    “Several” condors were seen near Fort Ross, Sonoma County, ca 1845-1846 [26]. In Napa County, condors were seen “in great abundance” in August 1845, and one was killed there in September 1845 [27]. A condor egg was reportedly collected in Napa County in 1845 [28]; unfortunately, there is no documentation of the actual event. Condors were seen in the Sacramento-San Joaquin delta area in spring 1847 [29]. In Marin County in July 1847, more than a dozen condors came to feed on a deer carcass [30]. In August 1849, one was shot in the Sacramento Valley near the junction of the Sacramento and Feather rivers [31], and in September of that year “several” were seen in the Yuba River canyon above Sacramento [32]. In October 1849, another was shot in the hills northeast of Marysville, and were seen regularly seen in that vicinity in November 1849, February 1850 (as many as 12), and March 1850 [33].

    The 1850s. -In July and August 1854, members of the Pacific Railroad Survey saw condors daily on their march up the Sacramento Valley and through the Siskiyou Mountains to the Klamath Basin (but “very few” there), and had “many opportunities of shooting them” [34]. Indeed, at least two had been shot in the Sacramento Valley earlier that year, one in March near Sacramento [35] and one in June near Chico [36]. Another was shot “in the coast ranges” sometime before April 1856 [37]. Between 1857 and 1860, condors were frequently seen in the Napa Valley, usually two or three together [38]. One was shot in Napa County in January 1858 [39], and others were reported in the hills “east of Marysville” in August 1858 [40].

   The 1860s. A condor was killed in June 1861 “in the coast range,” apparently in the Russian River area [41]. Another was shot in Plumas County in November 1865 [42], and a third in Mendocino County sometime before October 1867 [43]. Numbers in Napa County seemed to have declined after 1860 [44], but one was collected in nearby Marin County in August 1868 [45].

   The 1870s. Lyman Belding observed “a few” condors in Mendocino County [46], possibly in August 1870, when he spent several days in the Coast Ranges near the head of the Eel River [47]. He also saw condors on two or three occasions in the Sacramento Valley near Marysville, in winter but with no specific records given [48]. A condor was reported killed in Mendocino County in February 1872 [49], and one was shot in Marin County February 1873 [50]. One was reported flying near Mt. Shasta in September 1873 [51].

   The 1880s. In March or early April 1880, a condor was killed by an unspecified poison near the South Fork of the Eel River, Humboldt County [52]. One was shot in late April or early May 1880 in Tehama County [53]. Condors were seen “in the foothills southwest of Mount Lassen” between 1880 and 1884, probably by the same person who killed the condor in Tehama County [54]. A condor shot in the Feather River canyon was reported in November 1880, but may not have been killed then [55]. There was a condor held captive at San Rafael, Marin County, in the summer of 1882, that likely was acquired in the vicinity [56]. By the mid-1880s, Charles Townsend believed that the condor “has probably almost disappeared from Northern California, where it was once certainly common” [57].

   The 1890s and beyond. Early settlers in far northwestern California claimed that condors were plentiful there at one time. The last confirmed records were of individual birds shot in the hills east of Eureka in the fall of 1889 or 1890, and in the fall of 1892 [58]. I found no other confirmed reports of condors in California north of San Francisco until between 1900 and 1905, when one was killed in Marin County [59].

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   Because the above listing is not a sampling of condor records north of San Francisco, but is every apparently reliable record I could find, one might be left with the impression that condors were unusual in the northern part of their range. I think the dearth of records is more a reflection of the numbers and types of people who were in the area before 1900  than it is the number of condors present. The entire area of Oregon had only 52,000 people in 1860 [60]. The population had grown to 415,000 by 1900, but most of those people were still congregated around a few population centers in the Willamette Valley. The Umpqua River-Rogue River area of southwest Oregon - where condors were observed in 1826, 1841, 1903 and 1904 - in 1860 had less than 4,000 residents. In 1900, there were still less than 25,000 people in an area of over 8,000 square miles of rugged habitat in which condors were unlikely to be conspicuous [61].

   In northern California, the 1860 federal census of Del Norte, Humboldt, Mendocino, Trinity and Siskiyou counties recorded less than 25,000 people, most of whom were either miners or people living in the lowlands around Humboldt Bay. By 1900, that population increased to 70,000, but many lived at Crescent City, around Humboldt Bay, and around Ukiah, leaving some 18,000 square miles of mountains essentially uninhabited. In 1860, there were an average of less than two people per square mile; the density had increased only to four per square mile by 1900 - and considerably less over much of the area away from the main population centers [62].

   Human numbers were greater in the Sacramento Valley (85,000 people in 1860; 151,000 in 1900) and in the North Bay (33,000, growing to 108,000) than they were on the northwest coast. Population densities were also greater, increasing from four people per square mile to seven in the Sacramento Valley (23,000 square miles), and from seven to 23 in the North Bay counties (4,700 square miles). However, if you subtract that part of the Sacramento Valley population that lived in the city environment of Sacramento, as late as 1900 most of the Valley supported only about four people per square mile.

   All these numbers are presented to show that vast areas of northern California and western Oregon were so sparsely inhabited through the 19th century that condors could easily have gone unreported. Add to this a consideration of the type of people inhabiting the northern areas.  In all the area west of the Cascades and the northern Sierra Nevada, the scientific surveys had ended by 1855, and for the next 50 years the sparse Caucasian population had little time for the pursuit of natural history. The climate and the cultural environment of central and southern California attracted many people with the time and interest to study wildlife and collect birds' eggs. In contrast, the Northwest was populated mainly by homesteaders, miners, and the city merchants needed to support them. Few of these people left any kind of systematic records, and few mentioned birds. I have found no publications on birds of northwestern California between 1828 and 1887, and only five significant papers on birds of that area between 1887 and 1906 [63]. For western Oregon, I found only six papers on birds written between 1855 and 1895, and most of these were brief notes of birds seen near the Willamette Valley population centers [64]. After 1855, the first bird reference I can find for southwestern Oregon was from 1893 [65]. In other words, for the last fifty years of the 19th century almost no one was looking for any kinds of birds or birds’ nests in the Pacific Northwest.

   Combining this information with the pre-Caucasian record I think presents a clearer picture of condor occupancy. The prehistoric record is scant, but shows early condors in the same localities as later representatives of the species. Remains of at least 22 condors at one spot (The Dalles, Oregon) suggests either a significant local population, or regular visitation over a period of time. The detailed presence of the condor in myth, religion, medicine and celebration of a number of regionally separated aboriginal groups (at least in northern California, if not farther north) indicates a greater familiarity with condors than would have been gained from occasional visits of vagrant birds. (This contrasts with the aboriginal record of some other regions, in which unusual birds show up from time to time – often as harbingers of events to come – but do not have a solid place in the group ethos.)

   Many of the historic records are of individual condors that were shot or otherwise killed, and most give no indication of how many other condors were in the vicinity at the time. However, each region (Columbia River-Willamette Valley, southern Oregon-northern interior California, north coastal California, Sacramento Valley) has at least two reports that describe condors as common or of regular occurrence. Also, three of the four regions have records from every season (southern Oregon-northern California is missing specific winter reports) and from most months (Columbia River, 8 months; southern Oregon, 5 months; coastal California, 8 months; Sacramento Valley, 9 months). Clearly, in the area north of San Francisco, there were more condors at more times and in more places than would have been the case had all been vagrants or seasonal migrants from the south.

 Lack of Nesting Records

   The farthest north confirmed nesting records of California condors are from Santa Cruz County, California [66]. There is one alleged nest record from Napa County [67]; other than that, there are not even any credible rumors. (See Chapter 16.)  It isn’t surprising to me that no nest sites have been identified; no one looked for them while condors occurred in the northern areas. Explorers affiliated with fur trading companies or government expeditions made many of the condor observations. These explorers spent most of their time in the river valleys, the main travel routes through the region, so most condor observations were made of birds flying or feeding, not associated with potential nests or roosts. The few scientists who made their way deeper into mountainous areas (for example, David Douglas and Titian Peale in the Umpqua River area of southwest Oregon; Chapter 5) merely passed through, with no time for pursuing birds away from the expeditions’ established travel routes. The one early exploring party in northwestern California, Jedediah Smith's group in 1828 [68] saw condors. Smith recorded the sighting, but his party was too busy trying to survive to look for birds' nests. If the chances of even seeing a condor were slim, the likelihood of someone finding and reporting a nest was much, much slimmer.

Availability of Food for Condors. 

    As already noted, Carl Koford speculated that condors went north of what he considered their breeding range either because there was a particularly desirable food source that attracted them, or because they were forced north by food shortages in central and southern California. He opined that the first trip was made because of vital need for food. Finding not only food, but an especially attractive source, they returned even when there was no impetus for long-distance travel. Making regular sorties out of the breeding range eventually developed into a learned behavior within the condor population [69].

   Some aspects of condor population behavior go against a migration-for-food hypothesis. First, although condors are capable of traveling great distances, there are no 20th century records of condors (breeding or non-breeding) farther than 150 to 200 miles from a known nesting area [70]. In the 1930s and 1940s, Koford [71] found that most foraging by condors occurred within 35 miles of regularly used roosts, similar to what I observed in the 1970s. In the early 1980s, Meretsky and Snyder [72] equipped several condors with radio transmitters, and found most activity to be within 50 miles of nesting areas. Food for condors was drastically reduced in the 20th century compared to the previous hundred years [73], yet no scarcity forced condors to move beyond their expected range.

   Also, in the 20th century, condors were quite predictable in their seasonal movements north and south, away from and back toward nesting areas. Expected changes occurred regardless of local food availability. For example, condors moved south from summer roosts in the Sierra Nevada by September, although there was more potential food (dead livestock) in fall and winter than in summer. Similarly, movements north from nesting areas began by April, at which time local food supplies were still near their peak [74]. Regular provision of carcasses in one feeding area from 1972 through 1977 failed to disrupt these expected movements. When condors were in the area, they used the supplemental food; when it was "time to go," they left [75].

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   Considering the tenacity with which 20th century condors maintained their close ties to known nesting and roosting areas, and the seasonal regularity of their movements, it is difficult to picture a food situation either so dire in one area or so attractive in another that condor behavior would have been modified in the way Koford hypothesized. Actually, there is no evidence that any food shortage occurred in central or southern California that might have been severe enough to cause unusual movement of condors. The abundance of both wild and domestic large mammals there has been documented in Chapter 6, as have similar potential food supplies in the Sacramento Valley. If scarcity of food had been the impetus for condor travel north of San Francisco Bay, they would have had no need to go farther north than the Sacramento Valley. Had they gone on to Oregon during that period of "abounding" game in California, they would have found elk, white-tailed deer and black-tailed deer sometimes (as reported by human travelers) "plentiful" or "abundant." More often, however, they would have found what the human travelers found: only scattered herds, often not plentiful enough to provide adequate food for themselves [76].

   Koford [77] suggested two special food situations, either of which he felt might have been the original attraction that drew condors north from central California. The first was the potential availability of many mammals killed during the extensive fires set each year by Native Americans. The other was the tremendous biomass of spawned salmon that died along the Columbia River and its tributaries. Widespread burning throughout the Northwest is well-documented, and was done in part to improve habitat for game and in part to help with the hunting of game [78]. However, I could find no evidence of large numbers of mammals being killed in the frequent fires. In any event, burning of the land by Native Americans was also extensive and long-term in California [79], so the practice conferred no particular advantage on Oregon or elsewhere in the northern part of condor range.

   In hypothesizing about the importance of the Columbia salmon runs, Koford himself expressed concern that the actual record of condors feeding on salmon was confused because "hearsay is not always separated from fact" [80]. A close examination of the written record shows that John Kirk Townsend was the only person who ever claimed to have seen condors feeding on dead salmon. All other reports are apparently hearsay, based either on Townsend's one specific comment on the subject [81] or on a letter from Townsend that was included in Audubon's "Ornithological Biography" [82]. Even Townsend's reports on the subject are confusing. In his 1848 paper, he said “during the spring (1835), I constantly saw the Vultures at all points where the Salmon were cast upon the shore.” In his letter to Audubon, he repeated the information that condors were most common in spring, but later in the same letter, he wrote: “It (the condor) is seen on the Columbia only in summer, appearing about the first of June, and retiring, probably to the mountains, about the end of August. It is particularly attracted to the vicinity of cascades and falls, being attracted by the dead salmon which strew the shores of such places”

   Vultures are opportunistic scavengers, and condors may have eaten dead salmon along the Columbia River more often than is factually documented. Whether they did or not, spent salmon could not have been the special attractant that lured condors north. During the same period that condors were found along the Columbia River, salmon were abundant in the Sacramento-San Joaquin rivers drainage. Use of the salmon by Native Americans throughout interior California is extensively documented. The spring run of Chinook salmon in the San Joaquin River in the early 1800s has been described as "one of the largest Chinook salmon runs anywhere on the Pacific Coast," possibly numbering 200,000 to 500,000 spawners annually. Similar claims have been made about the Sacramento River, which had "the sole distinction among the salmon-producing rivers of western North America of supporting four runs of Chinook salmon – spring, fall, late-fall and winter runs" [83]. Chinook were the most abundant salmonids, but the Central Valley river system also supported four other species [84]. Condors were never reported feeding on fish in California, but there was no need to go to Oregon for them, had the condors wanted them.

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   Even if there had been a food incentive for long distance movement, it seems as if there had to have been resident condors beyond San Francisco Bay. The farthest north verified nest sites were in Santa Cruz, San Benito, and Tulare counties. Points approximately 200 miles north of those locations (considerably farther from nesting areas than any condors - breeding or non-breeding - would be expected to forage) are southern Mendocino County in the Coast Ranges, Yuba County in the Sacramento Valley, and Calaveras County in the Sierra Nevada. Practically speaking, there must have been additional nest sites in that 200-mile stretch. Even supposing that all condors reaching those northern locations had been birds from already confirmed nesting areas, that still leaves some 500 air miles to the Columbia River (and over 700 miles to British Columbia).  Seventy-five percent of the documented condor sightings north of San Francisco were made in that 700-mile stretch, and those observations were made during all seasons. Breeding condors were either regularly spaced throughout the northern area, or there were denser populations somewhere in every 100 to 200-mile segment.

   Condors were nearly gone from all areas north of San Francisco by 1900, but records found since Koford's study show the disappearance wasn't as early as he believed. Condors may have disappeared from the Columbia River area before 1850, as Koford thought, but there were condors in the Sacramento Valley at least into the 1880s (Koford thought 1860 at the latest). Koford tentatively accepted 1904-1905 records from southern Oregon, and into the 1890s for Humboldt County, California, but he could find no reports for the North Bay counties after 1870. I've been able to add records to show that condors were seen (and killed) regularly in Marin, Napa and Mendocino counties until at least 1900.  Although there is general agreement that, by the 1880s or 1890s, condors had become scarce in areas where they had once been common, it's possible that there were still remnant populations scattered throughout their former northern range into the early 1900s.

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   Why did condors disappear from the northern portion of their range? Of the three broad categories of impacts potentially affecting condors - decreased productivity, habitat change, and excessive mortality (Chapter 25), depressed recruitment seems unlikely. Condors were gone before the advent of chemical pesticides. If genetic bottlenecks were not a significant problem in the second half of the 20th century, greater numbers of condors and broader distribution would seem to have rendered it even less of an issue.

   There were habitat changes, but none that seem extreme enough or at the proper time to have greatly affected the northern condor populations. For example, the story of Caucasian America is often told as one of the pioneers clearing primeval forests, creating more open lands in what had been continuous woodland. In fact, in much of the United States – including the Pacific Northwest - the sequence was reversed. Regular, extensive burning by Native Americans slowed growth of trees and shrubs over vast acreage west of the Cascades from British Columbia south through Oregon, and through the Coast Ranges of northern California [85]. With major decreases in the aboriginal population after 1840, and with purposeful intent by Caucasian settlers to stop the burning, prairie lands began to revert to forest. For example, at the time of the 1853 land survey, prairies dominated the Willamette Valley. “The surveyors found no trees at all in the flat of the Valley, and had to utilize marking systems other than the traditional witness trees… Frequently, the surveyors, when working on the prairie, made the statement that there were no trees in sight” [86]. There appears to be no record of how quickly vegetation changed after the suppression of fire, but invasion of woody growth was being reported by the early 1850s [87], and by 1946 the Valley supported “large numbers of trees of the 90-year age class” [88].

   Of a smaller scale, but perhaps significant to any local population of condors, the “bald hills” of Humboldt County, California may be only half the size they were in the mid-1800s. Using the public land survey transects done 1875-1886: “Less than half (43.8 percent) of the nineteenth-century prairie points are found in prairie today. The conversion of historic prairie points is closely split between oak woodland or open timber (24.7 percent) and coniferous forest (31.5 percent)… The majority of prairie boundaries have shifted, representing a significant reduction in the areal extent of the Bald Hills prairies. Two-thirds of the prairie units have one or more nineteenth-century boundary points located more than 100 m from the modern prairie boundaries… Fifty percent of these historic prairie boundaries are now found in logged coniferous forest, 10 percent in encroached coniferous forest, 5 percent in uncut coniferous forest, and 27.5 percent in oak woodland” [89].

   I bring up this habitat modification just to discuss all possibilities, but I think it highly unlikely that either the amount or the timing of vegetation change affected the condors. It may have been that any detrimental effects of open land reduction were offset by increases in food supply as more domestic livestock were brought into the Northwest. If condors really were gone from the Willamette Valley and lower Columbia area by the 1850s, habitat changes could not have figured greatly in their disappearance there.

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   Condors were killed by humans, but I only found 38 specific instances north of San Francisco. Twenty-five occurred before 1860, with not more than four verified in any later decade. Thirty-six were shooting casualties; two-thirds of the ones before 1850 were taken for more or less scientific purposes, all the rest were shot for sport. One condor died of an unnamed poison (but probably strychnine); the cause of death of the final bird is unknown.

   The low number of reported deaths could be interpreted two ways. One is that the much sparser human population, compared to central and southern California, would have resulted in relatively few encounters between people and condors, with fewer chances for condor deaths. The other is that in the more rural north, with people living in more isolated situations and with fewer sources of published local news, a smaller percentage of condor deaths would have been reported than was the case in the south. If the first situation prevailed, then it is difficult to see human-caused mortality as an overriding reason for the disappearance of condors. If a significant number of deaths went unreported, then we need to consider the likely reasons for additional losses.

   Scientific collecting of condors ended in the northern areas before 1850, and almost all of it occurred in the Columbia-Willamette area of Oregon and Washington. Several people who killed condors had them mounted for display, but there was no real "hobby collecting" of condors north of the Bay Area. One condor was reported killed because of the belief it had killed livestock; losses from that motive would likely go unreported, but it is difficult to see it as cause for significant mortality. The only factors that are likely to have been more important than the record indicates are accidental poisoning from predator control, and sport shooting.

    Strychnine Poisoning. No condor is known to have been killed by strychnine in Oregon or Washington, and there is only one record from northern California. That doesn't entirely rule out the possibility that condors succumbed after eating poisoned meat. However, it appears that  condors had become rare in the Columbia-Willamette region long before strychnine came into use. In southwestern Oregon in the last two decades of the 19th century - with more people, more livestock, and apparently more strychnine - poisoning may have been more of a threat to condors than at any time previous. Nevertheless, the odds of a condor being poisoned in that vast area seems small.

   The situation in northern California was similar to southwest Oregon. Although people and livestock both increased in the region through the second half of the 19th century, northern California had more than one-third of the State's beef cattle in only one decade (the 1870s). The North Bay and northwest coast counties through 1900 never had more than about 15 percent of the northern California total. The sheep situation was similar: even as total sheep numbers in the State increased 1860-1880, there were never more than about one-third of the population north of the Bay Area. Perhaps more significantly, even when sheep numbers were high, the majority were found congregated in limited area. In 1860, over 50 percent of the sheep were in three counties, comprising less than 15 percent of the total northern California acreage. In 1870, three counties had 50 percent of the sheep on 10 percent of the available acreage. In 1890 and 1900, over 60 percent of the sheep were on 25 percent of the land. Only in 1880 were the sheep more widely distributed; even then, six out of the 22 northern California counties had almost 70 percent of the sheep, on 30 percent of the acreage [90].

   While strychnine was widely used for predator poisoning in western Oregon and northern California - and while much more was undoubtedly used than was strictly necessary - the popular belief that virtually every animal carcass on the range was laced with strychnine is clearly erroneous (Chapter 11). Granted that one poisoned carcass might kill a number of condors, in most places and at most times it would have been almost coincidental that any condor should find any strychnine bait. Strychnine was also used for rodent control, but apparently much more extensively in central and southern California than in the northern areas. It seems to me that, even if reporting was less frequent and less likely in the north than in the south, dead condors were so eye-catching that some losses would have been documented.

   Shooting. Thirty-six condors known shot in 100 years does not seem alarming.  What gives these shooting losses more significance is that, while deaths from poisons are speculative, condor deaths from shooting are documented in every decade and in all parts of the northern range. Whereas the greatest likelihood of condor poisoning would occur in only those areas of highest perceived need for predator or rodent control, shooting could occur anywhere. Condor shooters were not driven by just one motive, either. The desire to see a giant bird up close, or the desire to show off one's shooting skills, were just the most obvious reasons. Although only one record specifically mentions protecting livestock as the reason for shooting a condor, many cattlemen and sheepherders were wary of any large birds around their charges. Vultures spreading disease did not seem to be a widely held belief on the Pacific Coast, but it was prevalent in some parts of the United States, and it might have provided another excuse to shoot big birds. Finally, as detailed in Chapter 5, early trappers and explorers saw condors and eagles as competitors for food. Apparently, it was not uncommon for scavengers to get to shot game before it could be salvaged. Living off the land was seldom easy for these early travelers. Finding their hard-earned and much needed food devoured by condors and eagles would have been frustrating, but could also have been life-threatening if it was a regular occurrence. Reducing condor and eagle populations may have been both retaliatory (for past deeds) and preventative (to forestall future problems).

  Even after food for human survival became less of an issue, the spirit of competition between condors and hunters lived on. As Andrew Jackson Grayson  wrote in the late 1860s: "In the early days of California history it [the condor] was more frequently met with than now, being of a cautious and shy disposition the rapid settlement of the country has partially driven it off to more secluded localities. I remember the time when this vulture was much disliked by the hunter because of its ravages upon any large game he may have killed and left exposed for only a short length of time. So powerful is its sight that it will discover a dead deer from an incredible distance while soaring in the air" [91].

   It seems to me that condor losses to shooting are much understated in the available record. Nevertheless, even if the loss from gunfire was much more than the actual record shows, and even if strychnine poisoning was much more prevalent than seems likely, it's still doubtful there would have been enough impact from both combined to have caused the disappearance of condors over such a vast area. The truth about the losses in the northern condor range probably is much more nuanced and complicated.

*   *   *

An Hypothesis

    During my studies of California condors in the 1970s, it appeared to me that – even within the relatively limited range of the species by that time – the condors were not acting as a single population. To be sure that my surveys were adequately covering all parts of the range, I made special effort to increase condor records from the Coast Ranges between Santa Barbara and the Bay Area, by spending more time there myself and by recruiting new condor reporters. Yet, between 1966 and 1974, out of a total of 2,586 condor records, only 356 (13.7 per cent) were in the Coast Ranges, the rest being in the “Sespe-Piru” area of Ventura and Los Angeles counties, and northeast through the Tehachapi Mountains into the southern Sierra Nevada. Of even more significance, the largest group seen in the Coast Ranges during that period included only five condors, and that high a number was recorded only once in the 9-year period. In contrast, there were groups of over 10 birds seen every year in the eastern part of the condor range, groups of 15 or more in eight years,  and groups of over 20 in four years. The Carrizo Plains, one of the most used feeding areas in the Coast Ranges during Koford’s research in the 1930s and 1940s, did not produce any records of more than four condors together. The area still supported considerable livestock,  and was less than 25 air miles from highly used condor areas at the south end of the San Joaquin Valley.

   These findings led me to write the following [92]: “The regularity with which condors are observed in certain areas at specific times of year, and in relatively predictable numbers, indicates that at least two subpopulations of condors exist. The division in the population occurs near the Santa Barbara-Ventura County line.” Later writers erroneously stated that I believed “condors existed in two main subpopulations with a line of separation that was, at most, rarely crossed” [93]. Actually, I did not define a “line,” but a strip of land perhaps 25 miles wide, including parts of  Santa Barbara, Ventura, and Kern counties, in which I considered the “subpopulation affinity unknown.”

   Support for the subpopulation hypothesis came in the 1980s, when researchers were able to put radio transmitters on 11 condors, and follow their movements for from one to four years. Only four of the condors from my “Sespe-Sierra” subpopulation area had traveled more than a few miles into what I considered “Coast Range” habitat. One of these was a bird whose home territory was within my “subpopulation affinity unknown” area, and only one of the four birds made more than two trips outside the range I would have expected them to occupy [94]. It’s unfortunate that there were no radioed Coast Range birds farther away from the mixing area. Had there been, the hypothesis could have been better tested.

   It should not be surprising that, with birds as traditional in their movements as condors, groups associated with various nesting, roosting and foraging areas would - over time - develop their own seasonal movements. Time constraints would preclude long distance foraging by breeding condors, and a combination of distance and learned behavior seemed to define where and how far non-breeders would go. It would have been likely for condors from the Sisquoc area to mix on occasion with birds from the Sespe (nest area to nest area of about 40 miles). Condors from nests and roosts in central San Luis Obispo County might share habitat with Sisquoc birds (40-50 miles apart), but it would have been much less likely that they would regularly travel into Sespe territory. Similarly, condors resident in central Monterey County probably mixed regularly with San Luis Obispo birds, less regularly with Sisquoc condors, and rarely with the Sespe population. Each leg north (or south from the Sespe and Sisquoc areas) would render each group more isolated from those farthest from them, until distance alone would have precluded certain condors from ever meeting with one another.

   Without definite nest and roost site records, one can only speculate on the location and interrelationships of condor subgroups. Based on the historical record, I think that condors were yearlong residents from the Sierra San Pedro Martír in Baja California Norte, Mexico, north in the western mountains of California and Oregon at least to the Columbia River, perhaps farther. There were also condors resident in the foothills east of the San Joaquin and Sacramento valleys in California. Within their total range, subgroups of condors occurred where suitable nesting and foraging habitat existed together. Condors in each of these subgroups “homed” to their specific nesting areas, with their seasonal wandering taking them no more than 150 or 200 miles from “home base.”  No condor in Oregon ever met a condor from Mexico, but there was undoubtedly regular interchange between the nearest neighbor groups (probably in foraging areas seasonally populated by two or more groups, as occurred in the 20th century). Tenacity to a home nesting habitat gave cohesiveness to the subgroup, and for much of the year isolated its members from other condors. However, the seasonal mixing of subgroups improved the chances of new pair formation, and likely helped maintain diversity in the gene pool of each group [95].

   Subgroups such as I hypothesize for condors have been identified in many species of birds. In fact, because habitats are often fragmented naturally or the result of human land use, it has been suggested that it is "often relevant to consider populations as collections of subpopulations in heterogeneous environments rather than continuous entities," the relationships of the subpopulations to the whole depending on such factors as the distance between subpopulations, the relative sizes of the individual habitat areas, and the relative densities of the subpopulations [96].  Oliver Austin was one of the first to identify these subpopulations, noting that common terns live in small colonies, each of which maintains its membership, even though located only a few miles from other colonies [97]. More recent studies of gulls have shown even stronger affinities to the home site. For example, in black-legged kittiwakes "movement between their colonies was extremely rare once an individual bred," and "though this effect is more precise in the male, most females which change site move only a few meters from their nest site of the previous season" [98].  Sabine's gulls "showed strong tenacity to their breeding site from year to year, with most pairs nesting within approximately 100 m of the previous year's site [99]. Among waterfowl, pink-footed geese "form closed groups occupying small, well-defined areas" in which "the scale of mixing is negligible" [100], while among common eiders nearly all surviving females homed to the same breeding island year after year [101]. Ducks, crows, ravens, eagles, hawks, falcons, ospreys, owls, great tits, and flycatchers are other groups that have been shown to have strong "homing" instincts to a particular area and particular group of companions [102].

   In addition to the obvious limitations of birds separated by great distances getting together, the ties developed to a home habitat could inhibit the chances of pioneering into new or vacant habitat. For example, consider what is known about Canada geese. They’re one of the most abundant and most successful species of waterfowl in the world. Yet, if a local population of geese is removed from a  marsh (by overshooting, for example), that marsh  may not be nested in by Canada geese for many years.  Other members of the species from other subpopulations may fly over the area and see that suitable habitat still exists. Yet, their ties to their own home marshes are too strong for them to break, even for a marsh that might be much better than their own [103]. Hesitancy in re-pioneering areas formerly occupied by their species has been shown in various other waterfowl [104], in the common crow [105], and in the great tit. In the latter case, adult tits did not move from what was considered "suboptimal" habitat when better habitat became available nearby, but returned and reused their previously occupied locations [106].

*   *   *

   Considered on a subpopulation basis, the relatively meager record of condors in the northern part of their range takes on more significance. Condors along the Columbia and Willamette rivers were probably living near the margin of habitable range. The environment  was not unsuitable in any way, and condors survived there for hundreds of years. As observed by David Douglas and members of the Lewis and Clark expedition (Chapter 5), the condors were not noticeably affected by the cloudy, rainy weather of Northwest winters. Nevertheless, their body characteristics and behavior are clearly better suited to areas with greater amounts of open space and sunlight. Condors have high wing loading (the ratio of weight to supporting surface [107]), which results in a relatively short period each day when the atmosphere has warmed enough to develop the ascending currents needed for soaring flight. This "soarability" [108] is only 5 to 6 hours in winter in the southern part of their historic range, and 7 to 8 in summer [109]. Not only is the amount of time for foraging limited, the condors' late rising insures that they will be left with whatever food the earlier, more efficient scavengers leave them. In practice, this has meant that most of their food supply comes from large mammals, native or domestic, which most often inhabit grasslands and other open habitat. They were more likely to have this kind of habitat and type of food in the valleys of California than farther to the north. Comparing equal acreages of the Northwest and central California, the latter would almost certainly have a higher scavenger carrying capacity, and likely could support more condors per unit of land than the Northwest habitat.

   In fact, it appears that - although condors were widespread throughout the north - numbers were relatively low in any given area. Sometimes, words like "common" were used to describe local populations, but seldom were more than two or three reported together. The largest actual numbers recorded were of nine in a group [110], and "more than a dozen" [111]. No one north of San Francisco referred to the (probably exaggerated) "hundreds" regularly recorded in central and southern California.

   Under pristine conditions, the number of condors locally would not have been a problem. Although each population segment was relatively small, presumably they could sustain themselves as long as natality and mortality remained "natural." However, if a substantial number of condors were lost from a local group, there might not have been eligible birds nearby to join the remaining condors. Even if there were other condors within 150 miles or so, their ties to their own area could have inhibited them from pioneering into vacant habitat.

   I think the losses of condors in the Columbia River area - 10 positive in a 29 year period, and more suspected - could have been enough to destabilize that  population enough to lead to its eventual disappearance. Perhaps the losses of condors in Marin, Napa, and Mendocino counties, or in the mountains surrounding the Sacramento Valley, were enough to begin the decline at that end of the northern range. With the Monterey County condor population nearly exterminated (see below), there would be no close source of new recruits for the northern areas.

   There is too little information on the condors of northern California and the Pacific Northwest to bring this discussion to a very satisfactory conclusion. The population losses to the south are much easier explained.

 

SAN FRANCISCO SOUTH

  Overexploitation of subgroups of condors may explain the major declines in condor numbers in the central Coast Ranges (Monterey, San Benito, Santa Clara, and Santa Cruz counties), and in the area between Los Angeles and the Mexican border (Orange, Riverside, San Bernardino, San Diego, and southern Los Angeles counties). 

    In the central coast region, I have records of 68 condors known killed between 1850 and 1910. Forty-three of the deaths occurred between 1880 and 1900; 12 were killed in 1898, alone. Twenty-eight were killed as additions to private collections, while 15 went to zoos and public museums. Ten were victims of random shooting. Other losses are identifiable only as occurring in “southern California;” a number of them undoubtedly occurred in this region, also.

   This level of loss to a species that had no significant natural enemies, and which died mainly of old age, disease or accidents, had to have a major impact. If, as I believe, there was little interchange between condor groups to the north and south, the losses would have been disastrous. In fact, this is borne out by the record. The region including Monterey County was once a major condor nesting area, perhaps rivaling the Sespe-Piru area of Ventura County in the number of pairs supported. One-third of all the condor eggs known to have been collected came from Monterey County and adjacent parts of extreme northwest San Luis Obispo County. There are no certain nesting records after 1910, and after that condors were seldom seen except in the far southeastern corner of the county. The former nest sites were within 50 miles or so of condors nesting to the south, but there was apparently little or no pioneering of new pairs into the vacated area.

   In the area south from Los Angeles, there were 69 mortalities documented between 1870 and 1910. Half of those were random shootings, and 18 were believed taken for collectors. Only a few went to public museums. As had occurred in the central coastal counties, there were only a handful of condor reports for the vast southern coastal region after 1910. Condors remained relatively common just to the north of the Los Angeles Basin for 60 more years, and both nesting and feeding habitats were still available. No condors emigrated to fill the vacant niches [112].

   After 1910, most of the remaining California condors nested in Ventura and Santa Barbara counties, and adjacent areas of Los Angeles and San Luis Obispo counties. The disappearance of condors from much of their former range concentrated condor mortality - both legal and illicit - in that area. No condors are known to have been purposely killed in  Santa Barbara or Ventura counties until the 1870s (one record); during the 1880s and 1890s, the kill increased to 15 percent of the total. During the first decade of the 20th century, 30 percent of the loss occurred in those two counties; it was 50 percent between 1910 and 1920, and almost 70 percent in the 1920s. Although condors were still relatively "common" there for another 30 years, one wonders what would have been the case if collecting for zoos and museums had continued through another decade. The "annals of Gymnogyps" might have ended, with no chance to write any more chapters.

 

chapter notes

1. Pages 7-19 in: Koford, C. B. 1953. The California condor. National Audubon Society Research Report Number 4. New York, New York.

2. Koford 1953 op. cit., pages 129-135.

3. Koford 1953 op. cit., pages 8-11.

4. Wilbur, S. R. 1973. The California condor in the Pacific Northwest. Auk 90(1):196-198.

5. Personal communication between Carl Koford and Sanford Wilbur, June 1974.

6. Miller, L. 1911. Avifauna of the Pleistocene cave deposits of California. University of California Bulletin of the Department of Geology 6(16):385-400.

   Feranec, R. S., E. A. Hadley, J. L. Blois, A. D. Barnosky, and A. Paytan. 2007. Radiocarbon dates from the Pleistocene fossil deposits of Samwel Cave, Shasta County, California, USA. Radiocarbon 49(1):117-121.

   Feranec, R. S. 2009. Implications of radiocarbon dates from Potter Creek Cave, Shasta County, California, USA. Radiocarbon 51(3):931-936.

7. Miller, L. H. 1957. Bird remains from an Oregon Indian midden. Condor 59(1):59-63.

    Hansel-Kuehn, V. J. 2003. The Dalles Roadcut (Fivemile Rapids) avifauna: evidence for a cultural origin. Master of Arts in Anthropology, Washington State University (Pullman, Washington).

8. Specimen at the Royal British Columbia Museum, Victoria, British Columbia, Canada.

9. Nine Indian middens in the Puget Sound area yielded some 500 bones and bone fragments of various birds, but there were none from either California condors or turkey vultures. [Miller, L. 1960. Some Indian midden birds from the Puget Sound area. Wilson Bulletin 72(4):392-397.]

10. David Moen tried to connect the California condor to the mythical “Thunderbird” of various northwestern Washington and British Columbia aboriginal groups (Moen, D.B. 2008. Condors in the Oregon Country: exploring the past to prepare for the future. Masters degree project, Portland State University (Portland, Oregon). However, he did not cite (nor could I find) any reference that stated or implied that the condor was a model for the Thunderbird. The various Thunderbird motifs bear strong resemblance to raptorial birds, not vultures. If any “real” bird was the source of the myths, it would seem to me most likely to have been an eagle.

11. Page 65 in: Clyman, J., and C. L. Camp. 1926. James Clyman: his diaries and reminiscences (continued). California Historical Society Quarterly 5(1):44-84.

12. Pages 255-256 and 262 in: Putnam, R. 1928. The letters of Roselle Putnam. Oregon Historical Quarterly 29(3):242-264.

13. Finley, W. L. 1908. Life history of the California condor, Part II – historical data and range of the condor. Condor 10(1):5-10.

14. Peck, G. D. 1904. The Cal. Vulture in Douglas Co., Oregon. Oologist 21(4):55.

15. Page 180 in: Gabrielson, I. N., and S. G. Jewett. 1940. Birds of the Pacific Northwest. Corvallis, Oregon: Oregon State University.

16. Page 141 in: Cooper, J. G. 1860. Report upon the birds collected on the Survey. Chapter I, Land birds. Report on explorations and surveys to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean. Volume 12, Book 2. Washington, D. C.: Thomas H. Ford, Printer.

17. Page 166 in: Jewett, S. G., W. P. Taylor, W. T. Shaw, and J. W. Aldrich. 1953. Birds of Washington State. Seattle, Washington: University of Washington Press. The last record of the species for the state appears to be that of Dr. C. Hart Merriam (letter of January 4, 1921). In the early morning of September 30, 1897, Dr. Merriam saw a condor on the ground in open country a few miles east of Coulee City, Washington.”

  Even though Merriam had seen condors previously, I'm uncomfortable with this record. It is so relatively recent, and so far to the northeast of any other records, it seems anomalous. Researcher Maria Brandt reviewed for me the extensive Merriam archives at the Bancroft Library (Berkeley, California), but couldn't find correspondence about the sighting, and no journals or field notes that might have given additional information about the observation.

18. Credit is sometimes given to William Tolmie for a California condor sighting much farther north in British Columbia, at Ft. McLoughlin. On 24 November 1834, he wrote: “What I supposed a large species of vulture at the northern end [of the lake], along with some white-headed eagles attracted probably by the dead salmon.”[Page 293 in: Tolmie, W. F. 1963. William Fraser Tolmie, physician and fur trader. Vancouver, British Columbia: Mitchell Press Ltd.] The far northern location and the late time of year makes this unlikely; also, Tolmie made no mention of immature bald eagles, the logical large dark bird to be with adult bald eagles.

19. Page 291 in: Lord, J. K. 1866. The naturalist in Vancouver Island and British Columbia. Volume II. London, England: Richard Bentley.

20. Page 22 in: Fannin, J. 1891. Check list of British Columbia Birds. Victoria, British Columbia: Province of British Columbia.

21. Page 39 in: Rhoads, S. N 1893. The birds observed in British Columbia and Washington during spring and summer 1892. Proceedings of the Academy of Natural Sciences of Philadelphia 45(1):21-65.

22. Page 92 in: Sullivan, M. S. 1924. The travels of Jedediah Smith, a documentary outline including the journal of the great American pathfinder. Lincoln, Nebraska: University of Nebraska Press.

23. Two of llya Voznesenskii's California condors are still at the Zoological Institute, St. Petersburgh, Russia  (confirmed by Wladimir Loskot, Curator of the Department of Birds, 28 April 2008).  Two others have been gone from the Institute for many years, probably traded to other museums within a few years of Voznesenskii's return to Russia.

   The general timetable for Voznesenskii’s collecting is given in: Alekseev, A. I. 1987. The odyssey of a Russian scientist: I. G. Voznesenskii in Alaska, California and Siberia 1839-1849. Translation by W. C. Follette. Kingston, Ontario: The Limestone Press.

24. Poesch, J. 1961. Titian Ramsay Peale 1799-1885 and his journals of the Wilkes Expedition. Philadelphia, Pennsylvania: The American Philosophical Society.

25. Page 72 in: Cassin, J. 1858. Mammalogy and ornithology: United States Exploring Expedition during the years 1838, 1839, 1840, 1841, 1842, under the command of Charles Wilkes, U. S. N. Philadelphia, Pennsylvania: J. B. Lippincott & Co.

26. Page 406 in: Finley, E. L. (editor). 1937. History of Sonoma County, California: its people and its resources. Santa Rosa, California: Press Democrat Publishing Company.

27. Pages 137-138 in: Clyman, J. 1926. James Clyman, his diaries and reminiscences. California Historical Society Quarterly 5(2):109-138.

28. Page 177 in: Berner, M., B. Grummer, R. Leong, and M. Rippey. 2003. Breeding birds of Napa County, California. Vallejo, California: Napa-Solano Audubon Society.

29. Page 42 in: Wilbur, M. E. 1941. A pioneer at Sutter’s Fort, 1846-1850. Los Angeles, California: The Calafia Society.

30. Page 52 in: Bryant, W. E. 1891. Andrew Jackson Grayson. Zoe 2(1):34-68.

31.  Page 27 in: Johnson, K. 1967. The Gold Rush letters of J. D. B. Stillman. Palo Alto, California: Lewis Osborne.

32. Page 135 in: Clark, T. D. 1967. Gold Rush diary: being the journal of Elisha Douglass Perkins on the Overland Trail in the spring and summer of 1849. Lexington, Kentucky: University of Kentucky Press.

33. Pages 204-311 in: Reed, G. W., and R. Gaines. 1949. The journals, drawings and other papers of J. Goldsborough Bruff, April 2, 1849-July 20, 1851. New York, New York: Columbia University Press.

34. Page 73 in: Newberry, J. S. 1857. Report upon the zoology of the route (mammals and birds). Volume 6, Part 2, Report of explorations and surveys to ascertain the most practicable and economical route for a railroad from the Mississippi River to the Pacific Ocean. Washington, D. C.: Beverly Tucker.

35. Anonymous. 1854. California vulture. Sacramento (California) Daily Union, 11 March 1854.

36. Anonymous. 1854. A California vulture. Sacramento (California) Daily Union, 21 June 1854.

37. Anonymous. 1856. Nomen Laken Reservation. Sacramento (California) Daily Union, 1 April 1856.

38. Leach, F. A. 1929. A turkey buzzard roost. Condor 31(1):21-23.

39. Anonymous. 1858. Vulture. Daily Alta California (San Francisco, California), 4 February 1858.

40. Anonymous. 1858. The California vulture. Daily Alta California (San Francisco, California), 22 August 1858.

41. Anonymous. 1861. A large bird. Sacramento (California) Daily Union, 18 June 1861.

42. Anonymous. 1865. A huge bird. Sacramento (California) Daily Union, 25 November 1865.

43. Anonymous. 1867. A huge blow. San Francisco (California) Chronicle, 16 October 1867.

44. Leach 1929 op. cit.

45. Anonymous. 1868. Proud bird of the mountain. San Francisco (California) Bulletin, 19 August 1868.

46. Letter from Lyle Belding to Robert Ridgway 21 March 1878: “I have never shot a Cal Condor, have seen a few along Feather River in former years & a few in Mendocino Co.” Smithsonian Institution archives (Washington, D. C.), Division of Birds records 1874-1959, Record Unit 105.

47. Belding, L. 1918. Autobiographical sketch. Proceedings and Collections of the Wyoming Historical and Geological Society 16:127-184.

48. Belding, L. 1879. A partial list of the birds of central California. Proceedings of the U. S. National Museum 1:388-449.

49. Anonymous. 1872. Untitled [“vulture eagle” killed in Mendocino County]. Chicago (Illinois) Tribune, 24 February 1872.

50. Anonymous. 1873. California condor. Sacramento (California) Daily Union, 19 February 1873.

51. Avery, B. P. 1874. Ascent of Mount Shasta. Overland Monthly 12(5):466-476.

52. Anonymous. 1880. State news in brief. San Francisco (California) Bulletin, 5 April 1880.

53. Anonymous. 1880. State news in brief. Daily Evening Bulletin (San Francisco, California), 7 May 1880.

54. Page 201 in: Townsend, C. H. 1887. Field-notes on the mammals, birds and reptiles of northern California. Proceedings of the U. S. National Museum 10:159-241.

55. Seabough, S. 1880. Gold Lake, search for a mythical bonanza in the Sierras. San Francisco (California) Chronicle, 21 November 1880.

56. Page 89 in: Gassaway, F. H. 1882. Summer saunterings, by “Derrick Dodd.” San Francisco, California: Francis, Valentine & Company.

57. Townsend 1887 op. cit.

58. Smith, F. J. 1916. Occurrence of the condor in Humboldt County. Condor 18(5):205.

59. Specimen records, FMNH 39613, Chicago (Illinois) Field Museum of Natural History: collected in mountains north of San Francisco, Marin County, California, between 1900 and 1905.

60. Oregon population figures in this chapter were compiled from the Federal censuses, taken at ten year intervals throughout the United States.

61. The observations of California Condors in Douglas County, Oregon in 1903-1904 are usually considered to represent vagrant birds from far to the south, or misidentifications. However, William Finley conceded that, if condors were resident in the Northwest, “the last of these northern birds seem to have taken refuge in the rough mountain regions of southern Oregon.” [Finley, W. L. 1908. Life history of the California condor. Part II, historical data and range of the condor. Condor 10(1):5-10.

62. Compilations by California counties for each federal census 1860 to 1950, as well as the county size (in square miles), are given in: Gibson, C. 2007. Population totals by township and place for California counties: 1860 to 1950. Alexandria, Virginia.

63. Grinnell, J. 1909. Bibliography of California ornithology, First installment. Pacific Coast Avifauna Number 5. Berkeley, California: Cooper Ornithological Club.

    Grinnell, J. 1924. Bibliography of California ornithology, second installment to end of 1923. Pacific Coast Avifauna Number 16. Berkeley, California: Cooper Ornithological Club.

    Grinnell, J. 1939. Bibliography of California ornithology, third installment to end of 1938. Pacific Coast Avifauna Number 26. Berkeley, California: Cooper Ornithological Club.

64. Jobanek, G. A. 1997. An annotated bibliography of Oregon bird literature published before 1935. Corvallis, Oregon: Oregon State University Press.

65. Andrus, F. H. 1893. A nest (plum) full. Oologist 10:300.

66. Specimen records, FMNH 2909, Chicago (Illinois) Field Museum of Natural History: two California condor eggs collected July 1879, Santa Cruz County, California, by or for William A. Cooper.

67. Berner et al. 2003 op. cit.

68. Sullivan 1924 op. cit.

69. Koford 1953 op. cit., pages 9-11.

70. Page 27 in: Wilbur, S. R. 1978a. The California condor, 1966-76: a look at its past and future. North American Fauna 72. Washington, D. C.: U. S. Fish and Wildlife Service.

   Page 236 in: Wilbur, S. R. 2004. Condor tales: what I learned in twelve years with the big birds. Gresham, Oregon: Symbios.

71. Koford 1953 op. cit., page 52.

72. Meretsky, V. J., and N. F. R. Snyder. 1992. Range use and movements of California condors. Condor 94(2):313-335.

73. Wilbur 1978a, op. cit., pages 27-31.

74. Wilbur 1978a, op. cit., pages 7-12.

75. Wilbur, S. R., W. D. Carrier, and J. C. Borneman. 1974. Supplemental feeding program for California condors. Journal of Wildlife Management 38(2):343-346.

   Wilbur, S. R. 1978b. Supplemental feeding of California condors. Pages 135-140 in: Temple, S. A. (editor), Endangered birds: management techniques for preserving threatened species. Madison, Wisconsin: University of Wisconsin Press.

76. In addition to descriptions in the journals of the Corps of Discovery, Wilkes Expedition, and others, see discussions of the Northwest “game sink,” for example:

   Lyman, R. L., and S. Wolverton. 2002. The late Prehistoric-early Historic game sink in the northwestern United States. Conservation Biology 16(1):73-85.

   Kay, C. E. 2007. Were native people keystone predators? A continuous-time analysis of wildlife observations made by Lewis and Clark in 1804-1806. Canadian Field-Naturalist 121(1):1-16.

77. Koford 1953 op. cit., page 9.

78. Johannessen, C. L., W. A. Davenport, A. Millet, and S. McWilliams. 1971. The vegetation of the Willamette Valley. Annals of the Association of American Geographers 61(2):286-302.

   Fritschle, J. A. 2008. Reconstructing historic ecotones using the public land survey: the lost prairies of Redwood National Park. Annals of the Association of American Geographers 98(1):24-39.

   Bjorkman, A. D., and M. Vellend. 2010. Defining historical baselines for conservation: ecological changes since European settlement on Vancouver Island, Canada. Conservation Biology 24(6):1559-1568.

79. Anderson, M. K., and M. J. Moratto. 1996. Native American land-use practices and ecological impacts. Pages 187-206 in: Sierra Nevada Ecosystems Project: Final Report to Congress. Volume II, Assessments and scientific basis for management options. Davis, California: University of California, Centers for Water and Wildland Resources.

   Keeley, J. E. 2002. Native American impacts on fire regimes of the California coastal ranges. Journal of Biogeography 29(3):303-320.

80. Koford 1953 op. cit., page 9.

81. Townsend, J. K. 1848. Popular monograph of the accipitrine birds of N. A. – No. II. Literary Record and Journal of the Linnaean Association of Pennsylvania College 4(12):265-272.

82. Pages 240-245 in: Audubon, J. J. 1839. Ornithological biography. Volume 5. Edinburgh, Scotland: Adam & Charles Black.

83. Yoshiyama, R. M., E. R. Gerstung, F. W. Fisher, and P. B. Moyle. 2001. Historical and present distribution of Chinook salmon in the Central Valley drainage of California. Pages 71-176 in: Brown, R. L. (editor), Contributions to the biology of Central Valley salmonids. Fish Bulletin 179. La Jolla, California: Scripps Institution of Oceanography.

84. Williams, J. G. 2006. Central Valley salmon: a perspective on Chinook and steelhead in the Central Valley of California. San Francisco Estuary and Watershed Science 4 (3):1-398.

85. In addition to the references cited in Notes 78 and 79 above, see:

   Habeck, J. R. 1961. The original vegetation of the mid-Willamette Valley, Oregon. Northwest Science 35(2):65-77.

   Gregory, S., L. Ashkenas, D. Oetter, P. Minear, K. Wildman, J. Christy, S.Kolar and E. Alberson.  2002. Presettlement vegetation ca. 1851. Pp. 38-39 in: Hulse, D., S. Gregory and J. Baker (editors), Willamette River Basin Planning Atlas: trajectories of environmental and ecological change. Pacific Northwest Ecosystems Research Consortium. Corvallis, OR: Oregon State University Press.

    Dubrasich, M. 2010. Stand reconstruction and 200 years of forest development on selected sites in the Upper South Umpqua watershed. South Umpqua headwaters precontact reference conditions study. Western Institute for Study of the Environment (Lebanon, OR), White Paper No. 2010-5.

86. Johannessen et al., op. cit.

87. Gregory et al., op. cit.

88. Sprague, F. L., and H. P. Hansen. 1946. Forest succession in the McDonald Forest, Willamette Valley, Oregon. Northwest Science 20(4):89-98.

89. Fritschle 2008 op. cit.

90. California livestock information is based on figures given in Appendix II, pages 251-256 in: Burcham, L. T. 1981. California range land: an historico-ecological study of the range resources of California. Publication Number 7, Center for Archaeological Research at Davis  (California).

91. Page 52 in: Bryant, W. E. 1891. Andrew Jackson Grayson. Zoe 2(1): 34-68.

92.  Wilbur 1978a, op. cit., pages 9-11.

93. Meretsky and Snyder 1992, op. cit.

94. Meretsky and Snyder 1992, op. cit.

95. Wilbur 1973 op. cit.; Wilbur 1973a, op. cit. pages 7-13; Wilbur 2004 op. cit., pages 229-240.

96. Grosbois, V., and G. Tavecchia. 2003. Modeling dispersal with capture-recapture data; disentangling decisions of leaving and settlement. Ecology 84(5):1225-1236.

97. Austin, O. L. 1949. Site tenacity, a behavior trait of the common tern (Sterna hirundo Linn.). Bird-banding 20(1):1-39.

   Austin, O. L. 1951. Group adherence in the common tern. Bird-banding 22(1):1-15.

98. Fairweather, J. A., and J. C. Coulson. 1995. The influence of forced site change on the dispersal and breeding of the black-legged kittiwake Rissa tridactyla. Colonial Waterbirds 18(1):30-40.

99. Stenhouse, I., and G. J. Robertson. 2005. Philopatry, site tenacity, mate fidelity, and adult survival in Sabine's gulls. Condor 107(2):416-423.

100. Boyd, H. 1972. British studies of goose populations: hindsight as an aid to foresight. Pages 251-262 in: Population ecology of migratory birds: a symposium. U. S. Bureau of Sport Fisheries and Wildlife, Wildlife Research Report 2. Washington, D. C.

101. Wakeley, J. S., and H. L. Mendall. 1976. Migrational homing and survival of adult female eiders in Maine. Journal of Wildlife Management 40(1):15-21.

102. Hickey, J. J. 1942. Eastern populations of the duck hawk. Auk 59(2):176-204.

   Sowls, L. K. 1955. Prairie ducks: a study of their behavior, ecology and management. Harrisburg, Pennsylvania: Stackpole Company.

   Brown, L. H. 1972. Natural longevity of wild crowned eagles, Stephanoaetus coronatus. Ibis 114(2):263-265.

   Jenkins, J. M., and R.E. Jackman. 1993. Mate and nest site fidelity in a resident population of bald eagles. Condor 95(4):1053-1056.  

   Switzer, P. V. 1993. Site fidelity in predictable and unpredictable habitats. Evolutionary Ecology 7(6):533-555.

   Doncaster, C. P, J. Clobert, B. Doligez, L. Gustafsson, and E. Danchin. 1997. Balanced dispersal between varying local populations: an alternative to the source-sink model. American Naturalist 150(4):425-445.

103. Hochbaum, H. A. 1955. Travels and traditions of waterfowl. Newton, Massachusetts: Charles T. Branford Co.

104. Sowls 1955 op. cit.

105. Emlen, J. T. 1940. The midwinter distribution of the crow in California. Condor 42(6):287-294.

106. Switzer 1993, op. cit

107. Page 572 in: Fisher, H. I. 1946. Adaptations and comparative anatomy of the locomotor apparatus of New World vultures. American Midland Naturalist 35(3):545-727.

108. Page 26 in: Hankin, E. H. 1913. Animal flight. London, England: Iliffe and Sons.

109. Koford 1953 op. cit., page 52.

110.  Page 216 in: Douglas, D. 1914. Journal kept by David Douglas during his travels in North America 1823-1827. London: William Wesley & Son.

111. Bryant 1891 op. cit., page 52.

112. The situation in Mexico is unclear. Probably California condors nested at a number of locations between San Diego County and the Sierra San Pedro Martír in Baja California Norte. Some survived at least into the late 1930s, likely because they were more isolated and less subject to killing than were the condors in California. Periodic killing was reported, however, and all of Baja California Norte was subjected to a long-term drought that likely reduced the food supply. With no possibility of recruitment from the north, the Mexican population was eventually extirpated.


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