Hermit Warblers Research Articles

Nonbreeding Habitat Selection and Foraging Behavior of the Black-Throated Green Warbler Complex in Southeastern Mexico

Abstract We studied the ecological distribution and foraging behavior of three species in the Black-throated Green Warbler (Dendroica virens) species group in the Eastern Highlands of Chiapas, Mexico. The three species, Black-throated Green, Hermit (D. occidentalis) and Townsend's (D. townsendi) Warblers are largely allopatric on the breeding grounds and variably sympatric during the winter. We surveyed the composition of 166 mixed-species flocks and recorded habitat variables associated with the flock location along an elevational transect. We found that Black-throated Green and Townsend's Warblers segregated by altitude, whereas Hermit Warbler overlapped extensively with both other species. Even though Townsend's and Hermit Warblers co-occurred commonly in the same flocks, the latter showed strong selective use of pine trees and the former showed weaker selectivity of oak trees. Black-throated Green Warbler showed no tree-type selection. The combined differences in elevational distribution and tree-type use resulted in very low ecological overlap for the three species. The Black-throated Green Warbler was the most distinct in its foraging behavior, occurring more often in the outer and upper branches of trees, and using hanging, aerial, and hovering maneuvers more than its congeners. In addition, it showed a higher movement frequency and a lower rate of between-branch flights. The Black-throated Green Warbler also is the most morphologically distinct as a result of its overall smaller body size, which is consistent for the trend towards larger body size in more conifer-specialized species in this genus. We propose that as new breeding populations were founded, and speciation occurred, individuals of the more derived species occupied decreasingly productive winter habitats.

NONBREEDING HABITAT SELECTION AND FORAGING BEHAVIOR OF THE BLACK-THROATED GREEN WARBLER COMPLEX IN SOUTHEASTERN MEXICO1

Abstract We studied the ecological distribution and foraging behavior of three species in the Black-throated Green Warbler (Dendroica virens) species group in the Eastern Highlands of Chiapas, Mexico. The three species, Black-throated Green, Hermit (D. occidentalis) and Townsend's (D. townsendi) Warblers are largely allopatric on the breeding grounds and variably sympatric during the winter. We surveyed the composition of 166 mixed-species flocks and recorded habitat variables associated with the flock location along an elevational transect. We found that Black-throated Green and Townsend's Warblers segregated by altitude, whereas Hermit Warbler overlapped extensively with both other species. Even though Townsend's and Hermit Warblers co-occurred commonly in the same flocks, the latter showed strong selective use of pine trees and the former showed weaker selectivity of oak trees. Black-throated Green Warbler showed no tree-type selection. The combined differences in elevational distribution and tree-type...

A Phenotypic Test of Haldane's Rule in an Avian Hybrid Zone

AbstractWe introduce a phenotypic method to test for excess mortality in hybrids of the heterogametic sex, as expected from Haldane's rule, and apply this method to the unusually narrow hybrid zones between Hermit Warblers (Dendroica occidentalis) and Townsend's Warblers (D. townsendi) in the Pacific Northwest. Our test requires establishing comparable hybrid indices for male and female warblers. The hybrid index that we developed for females produced age-corrected distributions for phenotypically pure reference samples that closely matched those used by Rohwer and Wood (1998) for males. The similarity in these distributions enabled us to compare the relative frequency of males and females in hybrids and parentals. We detected no deficiency of hybrid females and thus no inviability in the heterogametic sex. Our failure to find evidence of the inviability component of Haldane's rule is not unexpected given the close relationship between these taxa; nonetheless, our methods should be generally useful for studies of hybrid zones.

Influence of Niche Overlap and Territoriality on Hybridization Between Hermit Warblers and Townsend's Warblers

AbstractHybrid zones between Townsend's Warblers (Dendroica townsendi) and Hermit Warblers (D. occidentalis) in the Pacific Northwest are narrow relative to estimated dispersal distances and appear to be moving, with Townsend's replacing Hermits. We examined whether the habitat-transition and parental-fitness asymmetry models can explain why these zones are narrow and moving by comparing habitat variables associated with warbler territories in the Washington Cascades hybrid zone. Habitat variables did not differ among phenotypes, suggesting that the habitat-transition model cannot explain the narrow and dynamic nature of this hybrid zone. Habitat characteristics of Hermit Warbler territories did not differ inside versus outside the hybrid zone, also suggesting that this zone is not associated with a region of habitat transition. The lack of difference in habitat use could be the result of comparing variables that are not important to pairing success. However, warblers tended to select territories on west-southwest aspects. South aspects in the southern Washington Cascades are dominated by Douglas fir (Pseudotsuga menziesii) and true fir, which is a habitat selected by female warblers when choosing among territories and males. The parental-fitness asymmetry model does not necessarily make predictions about habitat use within the hybrid zone but predicts the superiority of one parental species over the other. However, if significant overlap occurs in habitat use or niche (as in these warblers), then competition between parental species is likely to occur. To determine whether these species compete, we mapped 12 warbler territories and monitored an additional 94 territories throughout the breeding season and found that all males with neighbors compete for and hold exclusive territories. Thus, the pattern of habitat use and territoriality is consistent with the parental-fitness asymmetry model.

A PHENOTYPIC TEST OF HALDANE'S RULE IN AN AVIAN HYBRID ZONE

Abstract We introduce a phenotypic method to test for excess mortality in hybrids of the heterogametic sex, as expected from Haldane's rule, and apply this method to the unusually narrow hybrid zones between Hermit Warblers (Dendroica occidentalis) and Townsend's Warblers (D. townsendi) in the Pacific Northwest. Our test requires establishing comparable hybrid indices for male and female warblers. The hybrid index that we developed for females produced age-corrected distributions for phenotypically pure reference samples that closely matched those used by Rohwer and Wood (1998) for males. The similarity in these distributions enabled us to compare the relative frequency of males and females in hybrids and parentals. We detected no deficiency of hybrid females and thus no inviability in the heterogametic sex. Our failure to find evidence of the inviability component of Haldane's rule is not unexpected given the close relationship between these taxa; nonetheless, our methods should be generally useful for s...

Behavioral asymmetries in a moving hybrid zone

Three narrow hybrid zones exist between hermit and Townsend’s warblers in the Pacific Northwest. Character transition curves suggest that these zones are moving and that Townsend’s warblers have a selective advantage over hermit warblers. This study compares year-to-year return rates, male persistence on territories, pairing success, pairing patterns, and territory quality of hermit and Townsend’s warblers and their hybrids in the Washington Cascades hybrid zone. There was no difference in the year-to-year return rate between the parental species. Townsend’s males were more successful in maintaining territories and attracting mates than hermit males. Among mated pairs there were few hermit males compared to females, independently supporting the inferiority of hermit males in competition for territories or female mate choice for Townsend’s-like males. I found no difference in the quality of hermit and Townsend’s territories; however, in poor habitats Townsend’s males were more successful at attracting mates, suggesting female preference for Townsend’s-like males. In high-quality habitats, there was no difference in pairing success between the parental species. The fitness of hybrids relative to parentals affects the width and movement of the zone. Hybrids were intermediate in their ability to maintain territories and to attract mates, which should increase the width of the zone and accelerate its movement. Fewer hybrid males returned to from one year to the next, and among mated pairs there were few hybrid females relative to males, suggesting hybrid inferiority, which should narrow the hybrid zone and slow its movement.

Asymmetries in male aggression across an avian hybrid zone

Recent studies suggest that competitive asymmetries are causing the hybrid zones between hermit and Townsend’s warblers to move, such that Townsend’s warblers are replacing hermit warblers. Here we examine the contribution of male aggression to this competitive asymmetry by measuring aggressive responses to mounts. We presented male mounts of the two parental species to Townsend’s and hermit warblers outside the zone and to hybrids within the zone. Outside the zone, Townsend’s males are more aggressive to both conspecific and heterospecific mounts than are hermit males. This asymmetry should move the zone in the direction inferred from previous studies. Hybrids fall between parentals in their aggressiveness, which should accelerate the movement of the zone. Remarkably, we found no relationship between phenotype and aggression in individual males at a locality within the hybrid zone. The forces of selection and dispersal that maintain narrow hybrid zones should generate such a correlation if aggressive differences between the parental species are genetically controlled. We resolve this conflict by proposing a behavioral model of competitive sorting within localities. If birds are sorted across the hybrid zone according to competitive abilities, and competitive interactions within neighborhoods are more or less complete, then the correlation between phenotype and aggression within any given neighborhood will be eliminated. We tested this model by examining the relationship between phenotype and aggression across the zone. Warblers in hybrid neighborhoods on the Townsend’s side of the zone are more aggressive than warblers in hybrid neighborhoods on the hermit side, indicating that competitive sorting is occurring.

INFLUENCE OF NICHE OVERLAP AND TERRITORIALITY ON HYBRIDIZATION BETWEEN HERMIT WARBLERS AND TOWNSEND'S WARBLERS

Abstract Hybrid zones between Townsend's Warblers (Dendroica townsendi) and Hermit Warblers (D. occidentalis) in the Pacific Northwest are narrow relative to estimated dispersal distances and appear to be moving, with Townsend's replacing Hermits. We examined whether the habitat-transition and parental-fitness asymmetry models can explain why these zones are narrow and moving by comparing habitat variables associated with warbler territories in the Washington Cascades hybrid zone. Habitat variables did not differ among phenotypes, suggesting that the habitat-transition model cannot explain the narrow and dynamic nature of this hybrid zone. Habitat characteristics of Hermit Warbler territories did not differ inside versus outside the hybrid zone, also suggesting that this zone is not associated with a region of habitat transition. The lack of difference in habitat use could be the result of comparing variables that are not important to pairing success. However, warblers tended to select territories on west...

Mitochondrial restriction fragment length polymorphism (RFLP) and sequence variation among closely related avian species and the genetic characterization of hybrid Dendroica warblers.

To address several interconnected goals, we used mitochondrial DNA (mtDNA) sequences to explore evolutionary relationships among four potentially hybridizing taxa in a North American avian superspecies (Dendroica occidentalis, D. townsendi, D. virens, and D. nigrescens). We first compared the results of a previous restriction fragment length polymorphism (RFLP)-based study with 1453 nucleotides from the mitochondrial cytochrome oxidase subunit I (COI), ATP-synthase 6 (ATPase 6), and ATP-synthase 8 (ATPase 8) genes. Separate phylogenetic analyses of the RFLP and sequence data provided identical and well-supported hierarchical species-level reconstructions that grouped occidentalis and townsendi as sister taxa. We then explored several general features of mitochondrial evolution via a comparison of the RFLP and sequence data sets. Qualitative rate differences that seemed evident in highly autocorrelated comparisons of RFLP vs. sequence pairwise distances were not supported when autocorrelation was removed. We also noted a high variance in corresponding RFLP and sequence distances after the removal of autocorrelation effects. This variance suggests that caution should be used when combining RFLP and sequence-based data in studies that require the large-scale synthesis of divergence estimates drawn from sources employing different molecular techniques. Finally, we used our parallel RFLP and sequence data to design and validate a rapid and inexpensive polymerase chain reaction-RFLP (PCR-RFLP) protocol for determining species-specific mitochondrial haplotypes. This PCR-RFLP technique will be applied in ongoing studies of the occidentalis/townsendi hybrid zone, where the historic and geographical complexity of the interbreeding populations necessitates the genotyping of thousands of individual warblers.

Winter Ecology of the Endangered Golden-Cheeked Warbler

We studied the ecology of the Golden-cheeked Warbler (Dendroica chrysoparia) during three winter seasons, 1995-1998, in Honduras, Guatemala, and Mexico. Individuals of this species occurred almost exclusively as members of mixed-species flocks, occupying sites with greater densities of encino oak and ground cover and fewer pines than random sites. Most foraging observations were recorded in mid-story, encino oak. Commonly-observed foraging maneuvers were gleaning and sally-hovering. Eighty-three percent of foraging maneuvers were directed at the outermost portions of the oak foliage. Flocks in which Golden-cheeked Warblers occurred contained an average of 20.5 individuals and 12.9 species other than Golden-cheeked Warblers. The most frequently co-occurring species were Wilson's Warbler (Wilsonia pusilla), Black-throated Green Warbler (Dendroica virens), Hermit Warbler (D. occidentalis), Townsend's Warbler (D. townsendi), and Blue-headed Vireo (Vireo solitarius). The ratio of males to females observed was not substantially different from 1:1, and there was little evidence of sexual differences in habitat use. Golden-cheeked Warblers appeared to be tolerant of moderate levels of logging and grazing, but understory clearing to promote grazing for cattle may pose a significant threat to winter habitat availability.

Influence of Breeding Phenology and Clutch Size on Hybridization between Hermit and Townsend's Warblers

-In avian hybrid zones, differences in timing of breeding or clutch size may confer a selective advantage for one species over the other. We compared clutch sizes, arrival dates, pairing dates, and clutch initiation dates among Hermit Warblers (Dendroica occidentalis), Townsend's Warblers (D. townsendi), and their hybrids from areas within and adjacent to their hybrid zones in Oregon and Washington. Adult males of all phenotypes arrived first, with yearling males and females following by 10 and 18 days, respectively. Arrival was significantly later at higher elevations for adult males. The phenotypes did not differ in arrival dates when the effect of elevation was removed. Pairing dates were similar for the three male phenotypes, and clutch initiation dates were similar for the three female phenotypes. Thus, breeding phenology seems not to influence competition between these warblers and their hybrids. However, the clutches of Townsend's Warblers were 0.6 eggs larger than those of Hermit Warblers and 1.15 eggs larger than those of hybrids, suggesting a selective advantage for Townsend's Warblers. Hybrid females produced the smallest clutches we recorded (though not significantly smaller than Hermit Warbler clutches), suggesting that hybrids are inferior to both parental species. Received 16 July 1997, accepted 5 February 1998. HERMIT (DENDROICA OCCIDENTALIS) and Townsend's (D. TOWNSENDI) warblers are sister species that apparently diverged in Rocky Mountain (Townsend's) and coastal (Hermit) refugia during the middle Pleistocene (Bermingham et al. 1992). Three geographically isolated hybrid zones connect the ranges of these species, one in the Olympic Mountains of Washington, another in the southern Cascade Mountains of Washington, and a third in the Cascade Mountains of Oregon south of Mt. Hood (Rohwer and Wood 1998). The two Washington hybrid zones have been described in detail. For both zones, transitions from one parental phenotype to the other occur over 100 to 125 km, a distance only three to four times greater than estimates of root mean square dispersal (Rohwer and Wood 1998). These rapid character transitions imply that strong selective forces prevent these zones from becoming wider (Barton and Hewitt 1985, 1989). Rohwer and Wood (1998) evaluated a variety of models that might explain these narrow zones, and they concluded that both hybrid in3Present address: Department of Zoology, P.O. Box 118525, University of Florida, Gainesville, Florida, 32611, USA. E-mail: spearson@zoo.ufl.edu feriority and parental fitness asymmetries are keeping these zones narrow and, further, that parental fitness asymmetries are causing them to move. Hybrid zones will remain narrow when selection against hybrids is balanced by immigration toward the center of the zone by parentals (Barton and Hewitt 1985, 1989, Barton and Gale 1993). Asymmetric charactertransition curves also suggest that the Washington zones are moving southward, owing to the competitive superiority of Townsend's Warblers over both hybrids and Hermit Warblers (Rohwer and Wood 1998). Because this inference was based only on the shape of the character-transition curves, the competitive ranking of hybrids and Hermit Warblers could not be inferred. Several alternative models that can explain abrupt character transitions are not applicable to these hybrid zones (Rohwer and Wood 1998, Pearson 1997a). These include recent contact (Endler 1977, Barrowclough 1980), hybrid superiority within an ecotone (Moore 1977, Moore and Price 1993) and habitat modification (Gill 1980, Wake et al. 1980, Hewitt 1989: table 4). These warbler hybrid zones are interesting because the inferred fitness asymmetry implies that Townsend's Warblers are replacing Hermit

Three Hybrid Zones between Hermit and Townsend's Warblers in Washington and Oregon

We describe two hybrid zones between Hermit Warblers (Dendroica occiden- talis) and Townsend's Warblers (D. townsendi) in Washington, and introduce a third zone in Oregon. To quantify phenotypes, we scored eight standardized characters in each age class and summed them to form a hybrid index score. Because no linear geographic feature de- limits the hybrid zones between these warblers, we sampled the forests of Washington in a grid-like fashion to define the shape of the zones. For both Washington zones, the shape of the character-transition curves for the hybrid index suggests asymmetries in gene flow, with Townsend's-like phenotypes penetrating farther into the Hermit side of the zone than vice versa. Covariances between character states are high at the phenotypic center of the zone. Following Barton and Gale (1993), we use these covariances and the width of the zone to estimate cr, the root mean square dispersal distance. Both Washington zones are narrow rel- ative to cr, indicating that selection is preventing these zones from increasing in width. Hy- brid superiority within an ecotone, recency of contact, and habitat modification seem insuf- ficient as explanations for the abrupt transition that takes place in these zones. Asymmetries in the character-transition curves suggest that the zones are moving. We find no evidence that this inferred movement can be attributed to habitat changes or to differences in dispersal between the parental species. Other studies suggest that the primary cause of this inferred movement is behavioral dominance of Townsend's males over Hermit males. The shape of the zone in the Washington Cascades also suggests that Townsend's on the east side of the Cascade Mountains are better adapted to dry forests, possibly due to gene flow from pop- ulations derived from the Rocky Mountains. The third, isolated zone in the Cascade Moun- tains of Oregon offers unique opportunities to test this hypothesis. Received 25 June 1997,

Age-Specific Plumage Characters and Annual Molt Schedules of Hermit Warblers and Townsend's Warblers

We investigated age-specific plumage characters and the annual molt schedules of Hermit Warblers (Dendroica occidentalis) and Townsend's Warblers (D. townsendi), two closely related wood warblers that hybridize extensively where their breeding ranges overlap. First, we developed a method for aging spring males based on plumage characters. Previous authors have shown that adults of both species have black throats and immatures have yellow throats before their first prealtemate molt. However, because the throats of most immatures become largely black in this molt, distinguishing between the two classes becomes problematic in spring and summer. We established aging criteria based on the appearance of the rectrices and wing coverts that allowed us to age correctly 99% of birds whose age could be determined independently by throat color. Furthermore, we could assign 96% of birds to age cohorts based on either throat color or these criteria. Second, we documented the annual molt schedules for males of both age cohorts of both species. Birds complete the prealtemate molt on the wintering grounds, and the prebasic molt is essentially completed before birds arrive on the wintering grounds, although we found several birds in light molt south of the breeding range. Finally, we discovered several immature males of both species growing yellow, female-like feathers in the spring, supporting summer explanations for delayed maturation of the breeding plumage in these two species. Immature males differed from adults during the breeding season in several other plumage characters in addition to throat color.

Spring and Winter Bird Populations in a Douglas-Fir Forest Sere

Changes in bird species richness, abundance, and guild structure were compared among young (42-75), mature (105-165), and oldgrowth (250-500+ years) and between winter and spring, for 2 years in Douglas-fir (Pseudotsuga menziesii) forests of the southern Washington Cascade Mountains. In winter, bird species richness, diversity, and abundance were all greater in oldgrowth than in younger stands. The most abundant species were the chestnut-backed chickadee (Parus rufescens), golden-crowned kinglet (Regulus satrapa), pine siskin (Carduelis pinus), and red crossbill (Loxia curvirostra). In spring, there were few differences in diversity and abundance along the stand age gradient. Species richness showed a slight increase from young to oldgrowth. The most abundant spring species were the winter wren (Troglodytes troglodytes), western flycatcher (Empidonax difficilis), varied thrush (Ixoreus naevius), hermit warbler (Dendroica occidentalis), and chestnut-backed chickadee. The Vaux's swift (Chaetura vauxi) exhibited the strongest association with oldgrowth in the spring. Seasonal changes in abundance were greater in young and mature stands than in oldgrowth. This pattern was most noticeable among permanent resident species. A more favorable microclimate and probably better foraging conditions in oldgrowth in winter may explain the observed seasonal patterns of abundance. J. WILDL. MANAGE. 51(3):586-595 Even though the importance of the breeding season has been strongly emphasized as shaping bird communities, the winter season may be equally critical (Fretwell 1972), especially in regions where large numbers of species occupy the habitat throughout the year. Seasonal population changes, particularly of permanent residents, may provide an indirect measure of habitat quality. Forests of different age may provide different levels of resources, and therefore, may vary in quality. The published accounts by Raphael (1984) and Raphael and Barrett (1984) provided comparable studies for late successional Douglas-fir forests in northern California. The purpose of our study was to document the seasonal changes in bird community structure within a sere of natural Douglas-fir forests and o speculate on the effects of forest management on bird communities during both the winter and breeding seasons. We express our appreciation to M. Q. Affolter, B. Booth, J. B. Buchanan, C. B. Chappell, M. This content downloaded from 157.55.39.123 on Tue, 18 Oct 2016 06:04:41 UTC All use subject to http://about.jstor.org/terms J. Wildl. Manage. 51(3):1987 BIRDS IN DOUGLAS-FIR * Manuwal and Huff 587 Emers, K. W. Hegstad, A. Hetherington, A. B. Humphrey, D. A. Leversee, R. W. Lundquist, J. M. Mariani, B. R. North, M. J. Reed, B. A. Schrader, and L. A. Willimont for assistance with the fieldwork. N. J. Manuwal, J. G. Dickson, R. W. Mannan, R. W. Lundquist, and J. B. Buchanan provided valuable comments on the manuscript. We thank J. M. Mariani for many long hours of data editing and calculation of detection rates for the winter 1984-85 data, and J. R. Osborne for his computer expertise. We thank U.S. For. Serv. personnel at the Wind River, St. Helens, Randle, and Packwood ranger districts and Mt. Rainier Natl. Park personnel for various assistance. We acknowledge the support of L. F. Ruggiero, A. B. Carey, and F. B. Samson. This study was funded by contracts PNW-83-219 and PNW-84-227 and is Contrib. 44 of the Old-growth Wild. Habitat Res. Pro-

Four New Migrants for Costa Rica

Sightings of four species of migrant passerines not previously recorded from Costa Rica (Slud 1964; Orians and Paulson 1969; Dickerman 1971) are reported here. Vireo solitarius. Solitary Vireo. George V. N. Powell saw a bird of this species at Monteverde, Puntarenas Province, in the Cordillera de Tilarin in northwestern Costa Rica on 8 January 1971. The site was at 1540 m in Lower Montane Rain Forest (Holdridge 1967). The vireo attended a small mixed flock containing Golden-crowned Warblers (Basileuterus culicivorus) and Common Bush-Tanagers (Chlorospingus ophthalmicus). I saw a lone bird, perhaps the same individual, at the same location on 15 March 1971. The bird had a gray helmet, white lores and eye-ring (= spectacles), white throat, olive back, yellow wash on the flanks, and a heavy Vireo bill. This species has not previously been reported south of Nicaragua (Eisenmann 1955), where it is rarely encountered (T. R. Howell, pers. comm.). Dendroica occidentalis. Hermit Warbler. Peter Feinsinger and I observed a single individual foraging low in a planted row of Guatemalan cypress (Cupressus Benthami Endl.) along a wood's edge in Monteverde on 20 October 1971, elevation 1450 m. The bird fed alone though several other migrants, including Townsend's Warblers (Dendroica townsendi) and Black-throated Green Warblers (Dendroica virens), were nearby. The bird was in immature or female plumage and was identified by its gray crown, nape, and back; yellow cheeks with hint of dark auriculars; unmarked white throat, chin, and underparts. Numerous other North American migrants were present on this date. Dendroica townsendi. Townsend's Warbler. I saw this species frequently at Monteverde between 20 October and 5 April. Largest numbers (as many as six seen on 20 October 1971) and most frequent sightings occurred during the fall though a few birds were seen throughout the winter months. F. G. Stiles (pers. comm.) first observed the species at Monteverde on 16 September 1968. This is the earliest Costa Rican fall record. The bird was an adult male foraging in second growth. Edmund Stiles found a bird there on 28 January 1970. The species was present at Monteverde during four consecutive winter seasons: 1968-69, 1969-70, 1970-71, and 1971-72. The range in elevation of my sightings was from 1390 to 1540 m along the transition between Lower Montane Wet and Lower Montane Rain Forest zones in the vicinity of Monteverde. With the exception of two or three birds in isolated broad-leaf pasture trees, all individuals were found in edge situations, in or close by Guatemalan cypress plantings. Most Monteverde sightings were of fall-plumaged birds in which extensive yellow on the underparts and dark auriculars were used as primary field marks for their identification. A few spring birds were in plumages intermediate between those of winter and summer. Most Townsend's Warblers occurred in loose associations with other wintering migrants, usually with Blackthroated Green and Wilson's (Wilsonia pusilla) Warblers.

The Hermit Warbler in Washington

The Hermit Warbler in Washington

The Ornithological Writings of Chester Barlow

D URING the even decade of Chester 'Barlow's activity along literary lines more than fifty articles appeared to his credit, besides recently numerous editorials and short notes. His first article that I have found came to print in August, I902, in Lattin's Oologist where so many of us younger bird-students received our first inspiration to write up what we had learned. This first article of Barlow's was on the nesting of the ashy petrel on the Farallone Islands. He had visited these fascinating bird-islands and his discoveries there served also for several subsequent papers of remarkable interest to their younger readers, who longed to get to the oologist's paradise that was so vividly depicted. In 1893, within a few months after the founding of the Cooper Ornithological Club, its began to appear regularly in Taylor's Nidiologist. These reports were compiled largely from papers presented at the meetings. Here Barlow's good judgment and literary talent came into play in culling and compiling from the heterogeneous and often poorly-composed manuscripts those accounts we still find so full of interest. These Secretary's Reports continued for nearly four years, and are yet of high value for reference in regard to the life-histories of many western birds. During this period many signed articles also appeared dealing with bird-life in Santa Clara county. Here we find valuable articles on the nesting of the white-tailed kite and golden eagle. Then came the summer-vacation trips to the Sierra Nevada, and the delightful articles relating to its bird-life, not only pleasing, but of permanent value to science-important additions to the known histories of such birds as the hermit warbler, Calaveras warbler, olive-sided flycatcher and Cassin Vireo. With the inauguration of the Bulletin of the Cooper Ornithological Club in January, 1899, Barlow's really most important service to ornithology began, though his own signed articles became fewer. We probably never can sufficiently realize the great influence Barlow exerted in bringing out previously unknown observersurging them to contribute from their own stock of knowledge, and thus instilling that enthusiasm which when once well started may in time lead into the genius of a Coues. Barlow is not considered by some to have been a scientific ornithologist. He never wrote an article which was not intended for the merest beginner to read and enjoy. But I believe his career to have had a much more far-reaching influence on scientific ornithology than if he had entered, and confined his entire energy to, systematic or philosophic fields. 1892. The Ashy Petrel (Oceanodroma homochroa) on the Farallones. -Oologist IX, August 1892, pp. 193-194. 1892. Professional Egging; or the Collecting of Murre's Eggs in California. -Oologist IX, December 1892, pp. 255-257. 1893. A Day with the Creek Birds. -Am. Mag. of Natural Science I, May 1893, pp. 77-78. 1893. The White-tailed Kite and Prairie Falcon in California. -Oologist X, September 1893, PP. 258-260. 1893. Nesting of the Mallard Duck [near San Jose]. -Nidiologist I, November 1893, p. 38, 2 hftt. 1893. The Pileolated and Yellow Warblers [nesting in Santa Clara County]. -Nidiologist I, November I893, PP. 44-45. 1893. Nesting Habits of the Brandt's, Baird'sand Farallone Cormorants. -Am. Mag. of Nat. Science II, November 1893, pp. 53-54. 1893. Cooper Ornithological Club. [Secretary's Report, including notes on Lutescent Warbler, etc.] -Nidiologist I, December 1893, pp. 6o-6I. 1894. Collecting on the Farallone Islands. -Naturalist I, January I894, pp. 7-8.

Nesting of the Hermit Warbler in the Sierra Nevada Mountains, California

Nesting of the Hermit Warbler in the Sierra Nevada Mountains, California

Discovery of the Nest and Eggs of the Western Warbler (Dendroica occidentalis)

Discovery of the Nest and Eggs of the Western Warbler (Dendroica occidentalis)