SHORT COMMUNICATIONS j RaptorRes. 36(3):200-202 ¸ 2002 The Raptor ResearchFoundation, Inc.

SCHIZOCHROMISM IN A PEREGRiNE FALCON FROM ARIZONA

DAVID H. ELLIS 1 USGSPatuxent Wildlife Research Center, HC 1 Box 4420, Oracle.,AZ 85623 U.S.A.

LYNN W. OLIPHANT Departmentof l&terinaryAnatomy, University of Saskatoon,Sashatoon, Saskatchewan, S7N OWOCanada

JAMF•SK. FACKLER 5888 Inez Street,Bow, WA 98232 U.S.A.

I•Y WORDS: Per•ffrinePalcon; Falco peregrinus;albinism; There are a few published accounts of albinism in leuczsm;schizochromism; cannibalism. the Peregrine Falcon. McGregor (1900) noted a juvenile peregrine with two white secondaries(an example of in- Herein, we report the first record of schizochromism complete albinism) in Galifornia. A nearly pure white m the Peregrine Falcon (Falcoperegrrinus). Our example adult from Devonshire,England is housed at the Amer- is a nestling from southern Arizona. The lack of dark ican Museumof Natural History (specimenno. 453937). brown pigment in this bird made it closelyresemble the Sage (1962) included the Peregrine Falcon on the list of blue-grayplumage of an adult. Near fiedging time, the speciesfor which albinismis known for the British Isles. bird was eaten by its nestmates,so this article also docu- On 17 July 1978, we entered an eyrie in southernAr- ments cannibalism. izona (32-33øN, 110-111øW) where at least three nor- Abnormal pigmentation in wild birds is unusual (but mally pigmented young had fledged about 6 wk earlier. see Fitzpatrick [1980] for a speciesin which white patch- Gonspicuouslyscattered along the eyrie shelf and con- es are common), but aberrant, pale individuals have spicuousbelow the eyrie were hundreds of feathers,all been reportedfor many species(Sage 1962, Ross1973). still in the blood (i.e., all partially grown), of a pale nest- A BIOSIS search of the literature for only a 6-yr period ling that died at about 5 wk of age. Feathers matching located over 100 titles dealingwith abnormal plumagein this bird (and at least one peregrine talon) were also wild birds. found in castingson the eyrie shelf. We retrieved asmany Incomplete pigmentation can take many forms. True feathers as practical (at least 374 feathers, excluding or complete albinos lack all pigment, not only in plum- down). When these were assembled, we determined that age but alsoin talonsand iris. Incomplete albinosusually they representeda singlebird (i.e., we found 14 prima- have patchesof white feathersin otherwisenormal plum- ries, 9 secondaries, and 5 rectrices, none of which were age Schizochromismis the condition in which one or duplicates).On the cover of this issue,an array of these more pigments are lacking, while others are expressed. are displayedaround an illustrationof this youngfalcon, Sage (1962) mentions a Green Woodpecker (Picusviri- as it would have appeared in life. dzs)which waspure white except for its red crown.Some Many feathersof thisbird showpale brown (buff) spots torms of polymorphismare probablyderived from some where such would occur on a normal juvenile. Other form of albinism.A notable example is the pallid morph feathers have reddish tips just as for normal peregrine of thc australPeregrine Falcon (E p. cassini)of southern juveniles. These same fbathers, however, are pale bluish South America (Ellis and Peres Garat 1983). In this gray, where in a normal juvenile, they would be deep morph, juvenile and adult birds weaklyexpress the nor- chocolate brown. The extensivelygray contours result in mal color pattern (bars, streaks,etc.), but have much less this bird more closelyresembling an adult than a juve- pigmentation everywhere (a condition termed leucism), nile. Becauseof this resemblancewe suspectthat this especially in the areas that are lightest in normal pere- nestling,when it reached this level of development,dis- grines. In pallid falcons, even the talons and bill, black played enough of the adult sign stimuli that one of its and deep blue in a normal peregrine, are blond. parents responded as if it was an intruding adult and killed it. We cannot be certain that the pale bird was •E-mail address: dcellis@theriver. com killed by its own family,but the presenceof feathersand

200 SEPTEMBER 2002 SHORI' COMMt NI(;ATIONS 201

Figurc 1. A comparisonof feathersrepresenting various body areasfor the nestlingdisplaying schizochromism (right feather in eachpair) and two normally-pigmentednestlings (left fi•athers)l¾om Arizona thai died in approximate15the samestage of development.Illustrated topographic regions include (left to right, top to bottom):primary flight feather, secondaryflight feather,central rectrix. flank, alula, lateral rcctrix. Feathersfor the pale bird were normal in shape,so the shapedifikrences between the pale and normal feathersin each pair are due to pecnliaritiesassociated with exact locus.For example,the pale secondaryhas a more symmetricalvane tip showingthat it is from a more distalfifilicle than the normally-pigmentedsecondary. Also, the lateral rectricesare fi•om oppositesides of the tail. 202 SHORT COMMUNICATIONS VOL. 36, No. g

a talon in castingson the eyrie ledge dmnonstratethat it balismo pot parte de su propia familia. E1 plumaje de was eaten by the family.Also, the excellentcondition of esta ave mostraba una ausenctadel marr6n oscuro, pre- •ts feathers (i.e., few fault bars and none of great extent) sentando un manto de color gris p•lido sin diferencia al suggestthat it washealthy until the time of death. del adulto. Este es un ejemplo de esquizocromismo. While this individualcan be called partiallyalbino (i.e., Todo parece indicar que este fen6meno no habia sido somedark pigment is lacking) or leucistic(i.e., showing reportado en la bibliografia de la especie. color dilution), a better term for its condition is schizo- [Traducci6n de C6sar M•rquez] chromism (literally: split coloration). Traditionally,this ACKNOWLEDGMENTS term has been spelledschizochroism (see Van Tyne and Berger 1976:160,Hailman and Emlen 1985), but a sec- Our 1978 researchefforts in Arizona were funded pri- ond "m" is obviouslyneeded (chroma: Greek, color; marily by the U.S. Forest Service through the Rocky chromatic: English, relating to color). Such birds have Mountain Forest and Range Experiment Station. We ex- press our appreciation to John Schmitt for the cover some pigments,but not others. Our specimenwas nor- painting. This manuscriptbenefitted from reviewsby T.J. malfor buffand reddish brown (Fig. 1) butlacked deep Cade, R.W. Nelson, and R. Ritchie. Our thanks to each chocolatebrown, the most expansivecolor in the plum- We expressappreciation to William Campbelland Patrick age of normal juveniles. Coronado, both of NASA-Goddard Space Flight Center, Four clues lead us to conclude that the bird was eaten for arranging funding for publication of the color fig- by falcons on the ledge. First, and most convincing,a ures. talon and many small feathers were found in castings. LITERATURE CITED Second, most of the remains were found on the eyrie ledge (a •nam•nalianpredator would likely haveremoved ELLIS,D.H. AND C. PERESGARAT. 1983. The pallid falcon the carcassto consume it elsewhere). Third, the feathers Falcokreyenborgi is a color phase of the austral Pere- were plucked and scattered (as is characteristicof rap- grine Falcon (Falcoperegrinus cassini). Auk 100:269- tonal bird kill sites), rather than chewed off and matted 271. with blood and saliva(as is typical of mammalian kills). --, P.L. WHITLOCK, P. TSENGEG,AND R.W. NELSON Finally, at least three young fledged ti•om the eyrie: it is 1999. Siblicide, splayed-toes-flightdisplay, and grap- unlikely that the pale bird wastaken and eatenby a pred- pling in the SakerFalcon. J. RaptorRes. 33:164-167. ator of another specieson the eyrie shelf without the FITZPATRICK,J.W. 1980. A new race of Atlapetesleucopterua, predator killing additional nestlings.All of these facts with commentson widespreadalbinism in A. I. dresseft provideevidence that the pale nestlingwas consumed by (Taczanowski).Auh 97:883-887. its own family. Cannibalism has previouslybeen docu- HAILMAN,J.P. AND J.T. EMEEN.1985. A fawn-coloredBlack mented for five speciesof falcons including the pere- Vulture in Glades County, Florida. Fla. FieldNat. 13. grine (Ellis et al. 1999). 20. Feathers from this specimen, representing a wide MCGREGOR,R.C. 1900. A list of unrecorded albinos. Con- range of topographicregions, were depositedin the Uni- dor 11:86-88. versity of Arizona ornithological collection (UA no. Ross, C.C. 1973. Some additional records of albinism in 17828). North American birds. Cassinia 54:18-19. SAGE,B.L. 1962. Albinism and melanism in birds. Br. Birds RESUMEN.--Unpich6n muy p•tlido de Halc6n peregrino 55:201-225. (Falcoperegrinus) rue recuperado mucrto cnun nido al VANTYNE, J. ANDAJ. BERGER.1976. Fundamentalsof or- sur de Arizona. De las plumas y una garra cncontrados nithology.2nd Ed. John Wiley, New York, NY U.S.A. en una cgagr6pilaubicada al horde de un nido al sur de Arizona, al horde del nido, concluimos que hubo cani- Received30 July 2001; accepted14 April 2002