
Bird-Banding 190] NedK. Johnso't& July,1970 EL SAL VA DOR CHALATENANGO. Los Esesmiles,8700 feet; San Josedel Sacare, 3600 feet. MOI{AZON. N slopeMr. Cacaguatique,4600 feet. SAN MIGUEL. Mt. Cacaguatique, 3500 feet. HONDURAS MOSQUITIA. Intibuca, Esperanza, 5400 feet; Intibuca, 4 mi. SE Esper- a•za, 5900 feet. TEGUCIGALPA. Alto Cantoral; Cerro Cantoral; D.C.: i mi. NW Zam- breno; Monte Redondo. YORO. Portillo Grande, ¾oro, 4000 feet. ADDITIONAL NOTES ON THE FLYCATCHERS OF EASTERN NORTH AMERICA By ALLAN R. P•rs A• W•s•¾ E. LAN¾ON Bandors and, to some extent, museum workers have apparently found the paper by Phillips, Howe, and Lanyon (1966) to be a useful guide to the identification of flycatchers, particularly the genus Empidonax, in easternNorth America. When the need for a third printing developedthis year, it was suggestedthat we might wish to incorporatenew data and perhapsmake correctionsin the original text before reprinting. To avoid possiblebibliographic problems, we recommendedthat the 1966 paper be reprinted in its original form and that any further remarks appear in this supplement. Our principal objectives here are to provide a more comprehensive treatment of the five western species of Empidonax that were not included in the 1966 key, to add another Myiarchus flycatcher for considerationby easternbandors, to clarify the status of certain tyrannids in Florida, particularly southern Florida, and to com- ment further on the general problems of flycatcher identification that continue to plague bandors. Our discussionof such problems has been prompted by correspondenceand conversationswith a FlycatchersofEastern •Vor•h America [191 number of banders, more than we can acknowledgeindividually, but nevertheless we are grateful to all who have taken the time to pass along to us their commentson the 1966 paper. Dr. Eugene Eisenmann has been most helpful with suggestionsfor improving and clarifying our presentation here. Some banders have informed us that they believe the 1966 key to be too formidable, and they continue to searchfor a more simpli- fied alternative. We contend that there is no "simple alternative" to the correct identification of difficult groupslike Empidonax, and those who hopefully professotherwise are only creating a false sense of security that will foster and perpetuate the sametypes of dubious identifications that have characterized banding schedulesin the past. We believe that, with a little advance study, use of the 1966 key should not be unduly onerous. It is gratifying to note that, as indicated by the banding summariesof Operation Recovery stations in recent years, the number of "unidentified Empidonax" banded and releasedis on the decline. There could be two explanations:(1) banders have developed a greater expertise in identifying these birds, or (2) they are becoming increasingly reluctant to place a band on a bird that defies specific identification. Both of these trends, if real, are desirable and commendable. Every banding station must expect the occasional Empidonax that cannot be identified with certainty and these should be releasedunbanded or, if circumstanceswarrant, shouldbe collectedand referredto special- ists for study. An illustration, though obviouslyextreme, is a speci- men collected at the Kalbfleisch Field Research Station in Hunting- ton (Long Island), New York, on 28 August 1968, by JosephWun- derle, Jr., who recognizedit as being unlike any of the many Empi- donax that he had processed. Its characterscould not be reconciled with the key in the 1966 paper, nor could it be matched with any of the referencespecimens of western speciesin the genus. Sub- sequently both Phillips and Dr. Ned K. Johnson examined the specimen and independently agreed that it was an abnormally pigmented Yellow-bellied Flycatcher (E. fiaviventris) almost if not entirely lacking in yellow pigments. No bander could have been expectedto identify this individual properly. We shouldlike to reiterate the plea madein the 1966 paper for the use of multiple characters and the avoidance of undue emphasis upon single characters. Many banders regard as unnatural and cumbersomethe conceptof "the best fit" of a complexof characters, yet it is this desireto base an identification on "one good character" that has led to most of the problems,particularly with Empidonax. We are grateful to Dr. Kenneth C. Parkes for calling to our atten- tion a ease in point--a specimencollected on 1 October 1969 by Robert Leberman of the Powdermill Nature Reserve in western Pennsylvania. Leberman was impressed with the fact that the yellow pigment in this specimenwas concentratedin the area just above the dark chestband, unlike any of the hundreds of individuals that had been processedat Powdermill, and he was unable to key it out to his complete satisfaction. Lanyon subsequentlyexamined 192] AllanR. Phillipsand Wesley E.Lanyon Bird-BandingJuly, 1970 the specimen and had no hesitancy in calling it • Yellow-bellied Flycatcher and was able to match it with a nearly identical speci- men taken at the Kalbfleisch Station. Some of the characters were admittedly close to the extremes in the range of variation for the speciesas we know it at Kalbfleisch. For example,the 10th primary was shorter th•n the 5th by 0.5 mm. Only one out of 94 Yellow- bellled Flycatchers processedat Kalbfleisch ha.shad the 10th pri- mary shorter than the 5th, and in that instance the difference was recorded as 0.5 mm. also. In the 1966 key we allowed for this rare deviation from the norm for the species,as follows: "10th primary nearly always equal to or longer than the 5th" (italics introduced here.). We identify our term "nearly always" as being roughly equiwlent to the statement that "98 out of 100 individuals may be expectedto be so characterized". The use of a complex of characters (6th primary slightly cut out, short wing length, yellow wash just above the dark chest band, formula B -- •-3.4 mm.) provided •n unequivocal identification of this particular specimen, whereas the use of • single character, such as wing shape, could have led to confusion. For •nother example of the danger inherent in single character identifications, we call attention to • specimen of Acadian Fly- catcher (Empidonax viresce•s) netted •t the Kalbfleisch Station on 31 May 1969. The speciesis now a rare migrant on Long Island and this individual, the first record for the station, was photo- graphed for coloration of soft parts (flesh-coloredmouth lining, not orange; gray t•rsi, not black) and later collected as • voucher specimen. The fact that the plumage of the throat was conspic- uously tinged with yellow might well have influenced some banders (and field observers) to identify the bird as • Yellow-bellied Fly- catcher. We pointed out in the 1966 paper that most Acadian Fly- catchers return in the spring with the throat white, but that some spring sight recordsof Yellow-bellied Flycatchers, suspectbecause of their early d•tes, might well be of yellow-throated Acadians. The Kalbfleisch specimen,identified on the basis of a complex of char- •cters (long wing length, wing shape, color of mouth lining and of tarsi), reinforcesthis belief •nd •mplifies our concern over the use of single characters. We would again stressthe use of multiple charactersin identifying Western Kingbirds (p. 160), as other yellow-bellied kingbirds have been taken in the e•st and m•y be increasing. The important feature of Western Kingbirds is the even, contrasted t•il, largely bl•ck but with abrupt white outer web of the outer rectrix. Cassin's Kingbird (T. vociferans)lacks this contrasting white. TropicM kingbirds l•ck both black •nd white, the t•il being dark brownishto dusky and notched (or even forked in someforms). Their identifica- tion is extremely critical, and no usablekey exists•s yet; they should be preservedas museum specimensuntil such a key, now being prepared, is published. The generalizationsgiven in the 1966 p•per relating to migration schedulesand presenceor •bsenceat specifictimes of the year have, Vol.41, No. 3 FlycatchersofEastern iVorth America [193 for the most part, been substantiated. Some departureshave been brought to our attention but, with few exceptions,are not significant enough to merit presentation here. Dr. Parkes has informed us, however, that data accumulated at the Powdermill Nature Reserve suggest that both Yellow-bellied and Traill's Flycatchers continue to move through western Pennsylvania,in small numbers,into early October, and that station has one record of a Traill's as late as 11 October and of a Yellow-bellied Flycatcher as late as 30 October. We are most appreciative for the splendiddata sent to us by Dr. William B. Robertson, Jr., and John C. Ogden, which help to clarify the distributional status of certain flycatchers in Florida. Consequently,some of the statementsin the 1966 paper need to be corrected or amended, and we refer the reader to the appropriate page numbers. Since the Eastern Wood Pewee, Corotopusvirens (p. 158), is known to have nested in Volusia County, Florida, the speciesmay be present in the northern part of the state during the summer months. Great Crested Flycatchers, Myiarchus crinitus (p. 159), winter rather commonly in parts of southern Florida, i.e. Palm Beach south to •[atccumbe Keys. The Gray Kingbird, Ty- ran•us dominice•sis (p. 160), breeds up to 10-15 miles inland from the coast of Florida, chiefly in towns, and migratesthroughout the interior of southern Florida. Western Kingbirds (p. 160), and Scissor-tailed Flycatchers, Muscivora forficata (p. 161), winter rather commonly (October to June) in the southern half of Florida, including the keys, and are regular transients (especiallyin October and November) on the Gulf coast below Tallahassee. The Least Fly- catcher, Empidonax minimus (p. 161), winters regularly on the south Florida mainland, mainly in "dense thickets on low ground" (fide Robertson), and is fairly common there from September through October. This is the commonestspecies of Empidonax in southern Florida after the first few days of October.
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