Bird Listing and the Field Observer*
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BIRD LISTING AND THE FIELD OBSERVER* Lester L. Short, Jr. I have beenimpressed for sometime by the restrictivenature of bird check-lists,used by field observersto tally their "scores"of speciesseen in an area. While suchlists are an invaluableaid to beginningbirders, to experiencedobservers in an unfamiliararea, and to veteranobservers in summarizingtheir observations,too often theyconstitute the sumof the observer'srecords. Lists of birdsinvariably follow someauthority, and beingsimple lists they maskmany interestingproblems and discourage the useful accumulationof meaningfulbiological data. Of coursenot every observeris personallyinterested in putting forth effort for the advancementof ornithology,but unconsciouslyhe is makingthe obser- vationsthat qualifyhim to do so. With very little extra effort an ob- servercan increase the valueof his observationsgreatly. Perhapswhat is needed to facilitate this is a new form of field check-list. Such a check-list(I have neverseen one) certainlywould not be a simplespecies list. Rather, eachspecies would have space for notation of all readilyidentifiable forms, such as juveniles, females, males, eclipse plumage males. Recognizablehybrids would be included, as would subspeciesthat are identifiablein the field. Yet sucha list wouldpro- bably createas many problemsas it solved,primarily becauseit too would encourageprecise determinations even in caseswhere this is not possible.In fact, thereis no substitutefor field notesrelating to one's observations.Only in this way canthe featuresof a putativehybrid or very rare bird from elsewherebe placedon record,and madeavailable for future consideration. Challengesfor thefield observer are many, and as he gains experience in observingbirds in various places at diversetimes of theyear, he isable to contributeever more to ornithology.Even a beginneracquainted with theMallard Duck, instead of recordingsay "60 mallards,"can maximize his observationsby recording,for example,"32 males,28 females, mainlyin pairs,"or notingif youngare present, or malesare in eclipse plumage,etc. Simplicityin recordingobservations is a gravefault, mini- mizingthe observer'spotential contribution. All odd birds,in fact anythingout of the ordinary,should be des- cribedfully by the observerin a field notebook. The carefulobserver *Someportions of this articletreat materialdiscussed by me in the Linnaean News-Letter, vol. 23, nos. 8-9, 1970. Calif. Birds 1: 143-145, 1970 143 BIRD LISTING AND THE FIELD OBSERVER will give at least a glanceat any singingbird - hybrid birdsmay sing songslike thoseof their parentalspecies, and there are records of birds singingsongs like thoseof other species.Peculiarities of plumagemay be an indicationof mutation(mutants ought to be noted,and albinistic or partly albinisticbirds shouldbe described,etc.), or a hybrid may be involved.In all casesa full descriptionis preferableto anyshort-cut tab- ulation. For example,a "Brewster'sWarbler" listing for a Blue-winged x Golden-wingedWarbler hybrid hasrelatively little informationcontent (seeShort, Proc. XIII Int. Ornith.Congress, pp. 147-160,1963, for a dis- cussionof the greatvariation in thesehybrids). A "hybrid flicker" is not a good or even a valid notation,for Californiabreeding flickers ex- hibit manyindications (sometimes so strong that the birdsresemble true hybridsfrom the hybridzone) of introgression,that is of geneflow from thedistant hybrid zone, and from the eastern flicker populations (Short, Bull. Amer. Mus. Nat. Hist., vol. 129, pp. 307-428, 1965). Callingan introgressantbird a "hybrid" impliesthat it is a vagrantfrom the zone of hybridization,whereas the individualactually may belongto the Cali- fornia breedingpopulation. It is difficult to determineflicker hybrids in the Westbecause of strongintrogression, although generally the hy- bridsshow intermediacy in severalcharacters (e.[., "moustache"color, napepatch, shaft color), whereas introgressants usually show intermedi- acyin onecharacter, or baretraces of introgressionin severalcharacters. Hence the needfor accurate,detailed descriptions of putativehybrids (hybridsdo indeedoccur in numbersin the Westduring migration and in winter). I shouldnote that my treatmentof the variousNorth Ameri- canflickers as conspecific is a taxonomicmatter, irrelevant to the field observer'stask of identifyingthe identifiable. Rather than becomingbelligerent at criticismof his observations,the observershould encourage and welcomecriticism. Not only doesthe observergain experiencefrom suchcriticism, but the ultimatevalue of the observer'srecords are dependentupon his provenability, and this ability must be demonstratedto field experts. Theseexperts, usually regionalspecialists engaged in compilingand maintaining records, must be skeptical,for only by beingcritical can they insurethe validity of the reportsemanating from their region.Such care is typicalat all levels for the recognitionof records;the AmericanOrnithologists' Union Com- mittee on Classificationand Nomenclatureis equallycritical of records asare (or shouldbe) regionalcompilers. Let me concludeby statingthat I am not "against"bird listingas such. Some of my goodfriends, indeed even someprofessional orni- thologists,are spare-timelisters. And many of us mentallynote new 144 BIRD LISTING AND THE FIELD OBSERVER birdswhether seen at foreignairports, museum gardens abroad, or wher- everwe happento be (it is sensiblefor an ornithologistto seeas many kinds of birds as he can, and many ornithologistsstarted their life's work with that asan initial aim!). However,my point is that we should encourageat all timesaccurate, detailed observations recorded on paper (or on tapes). Theseshould take the placeof the unrecordedmental notesusually accompanying simple listing. AmericanMuseum of Natural History, New York, N.Y. 10024. NOTES A RED-FACED WARBLER REACHES CALIFORNIA On 30 May 1970 Xenia and Pierre Devillers and I found a Red-faced Waxbier Cardellina rubrifrons at the Brock Ranch situated about 20 miles east of Holtville, Imperial County, California. This bird wasalone in a cottonwood,and responded to "squeaking",descending from the upper portions of the tree. It moved around rather slowly on the outermostportions of the limbs,remaining motionless, with wings partially extended and bill open, for short periods of time, for the tem- peraturewas close to 100ø. Thefollowing description was obtained: The forehead,t•oat, and upperbreast were a dirty pink, paleston the breast. The top of the head wasblack, with the black extendingdown the sidesof the face behind the eye to include the ear coverts. A small dirty white area on thenape sepaxated the black of theblack top of thehead from the gray back. The back, wingsand tail were gray; the wing covertswere edgedwith dirty white, producingtwo rather indistinctwing-bars on eachwing. The rump was dirty white. The belly and crissumwere dirty white, and the flankswere a very palegray. The bill wasblack, and lookedrather stubby and thick. Calif. Birds1: 145-146, 1970 145 .