Survival and Fitness of a Female Northern Cardinal (Cardinalis cardinalis) after Partial Loss of Melanin-based Feather Coloration

Peter H. Homann 117 Ridgeland Road Tallahassee, FL 32312-1906 [email protected]

ABSTRACT METHODS AND RESULTS

An incidence is described of a female Northern In a wooded area near my home in Tallahassee, Cardinal'slosing the abilityto producemelanin over FL, I banded on 1 2 Jul 1996 a normal-looking part of its body when its plumage was replaced hatching-yearfemale NorthernCardinal (band 871- duringthe fourthprebasic molt. The mostdramatic 60837). No changesof the plumagewere apparent abnormalitywas apparent in the feathers of the through 31 Dec 1998, the date of the eleventh crest,head, nape,throat, rump and wings,but only recapture after banding. It was not until 18 Mar head, nape, throat, and rump became colorless, 2000 that I captured the bird again, and at that i e. white,because the feathersof the otherregions timeits head, nape, breast,and rumpwere entirely producedcarotenoid-based red colors,which they white except for some red in the crest (Fig. 1). retained. The cardinal survived for at least another Furthermore,many covertsof the wingas well as two and one-halfyears withoutfurther change of a few flight feathers and one central rectrixwere the plumage pattern. This time period included pinkishred ratherthan havingthe normalcoloration three breedingseasons during which the birdwas of brownmixed with red. Becausethe only possible observedto be reproductivelyactive. occasion for feather replacement between December1998 and March2000 was the prebasic INTRODUCTION molt in the fall of 1999, it must be concluded that at that time melanin-typepigments had not been Localized losses of melanin productionin birds depositedi n t he f eathers of p arts o f t he body resultin patchesof plumagethat are whiteor retain althoughtheir carotenoid-based red pigments were only melanin-independent coloration such as retained. carotenoid-basedreddish hues. A patchywhite appearance due to melanin loss is referred to as After the encounter with the bird in March 2000, I leucism; but when the loss of melanin occurs in recaptured it another seven times at the same regionswhere otherpigments are presentas well, location,Iast on 13 Apr 2 002. Unfortunately, the condition can be referred to as schizochroism comparisonsof the aberrant plumagein pictures (Harrison 1 985). Albinism, i n contrast, is t he taken in 2000 and 2002 were somewhat consequenceof a totalpigment loss over the entire inconclusivebecause the true colorson the wings body,including eyes and body parts not covered in t he picturestaken i n 2 000 a re obscured by by integumentslike hair or feathers(Harrison 1969, shadows.Nevertheless, if changes in the plumage Harrison1985; Buckley1987). Here I reportwhat had occurredsince 2000, they were very minor. m•ght properly be called an instance of Of the wings, the more informativephotographs spontaneouss chizochroism in a three-year old from2002 are shownbecause they documentthat female NorthernCardinal (Cardinalis cardinalis) the extent of pigmentaberration was not identical that survivedfor almostanother three years. on the rightand leftwings (Fig.2).

Oct-Dec 2003 NorthAmerican Bird Bander Page165 The birdappeared to be perfectlyfit, as it not only survivedbut attracted a mate: When I caughtthe birdin spring2000, I noticeda broodpatch, and I discovered her nest in July, which fell victim to predationafter the younghad hatched. In March 2001, I observedthe abnormallyplumaged female in the companyof a male;and when I capturedher on 13 Apr 2002, she again had a brood patch. Indeed, on 20 May 2002, I discoveredher on her nest,apparently incubating, but four days later the veryconspicuously located nest was desertedand empty. This was my last recordbecause I did not encounterthe bird again.

DISCUSSION

Albinism, leucism and schizochroism are not rare occurrencesamong animals. Indeed, free-living birdshaving patchy white or even completelywhite plumagesare describedor documentedquite often. Encounters with such birds usually are s ingle events, however, and do not reveal whether the abnormalpigmentation was presentat hatch or Fig. 1. Female Northern Cardinal after spontaneously acquiredlater in life, and its effects on the bird's turning schizochroic. The underside of the bird has fitness remain unknown. Even so, instances of a retained the normal brown coloration, whereas many of spontaneousappearance of a leucisticplumage the wing coverts are rose-colored because melanin is absent. (I thank Dr. P. Rutkovsky for taking the patternin free-livingbirds have been reported. Of photograph when I captured the bird on 18 Mar 2000.) such observations I will mention three, one of a

Fig. 2. Left and right wing of the schizochroic Northern Cardinal on 13 Apr 2002. Many of the melanin-deprivedrose- colored feathers appear almost white in these black-and-white reproductions of the color photographs. Page 166 North American Bird Bander Vol. 28 No. 4 Gray Catbird(Dumetella carolinensis) and the other conclusions about the underlying genetic two of Song Sparrows(Melospiza melodia). dispositionsor about the nature of physiologicalor environmentaltriggers if such are involved. In the The reported spontaneous appearance of white in specificcase of this NorthernCardinal, the pigment the plumageof a catbird occurred in the time span abnormalityappeared spontaneouslyafter several of 40 days between two captures. It took place normal molts, and subsequent molts neither duringthe first prebasicmolt and affected only the reversed nor exacerbated it. The extensive loss secondprimaries of bothwings (Keith et al. 1999). of pigmentation had no noticeable effect on the Root (1944) had a similarexperience with a Song reproductiveactivity of the bird, perhaps because Sparrow. He had banded a normal-lookingbird in the affected individual was a female and, therefore, Massachusettson 26 Sep 1941 and recaptured it could choose a mate rather than havingt o b e a monthlater on 24 Oct, showing"incomplete and chosen(see Wolfenbarger1999). Its longsurvival asymmetrical a Ibinism." Root describes white may be attributable to the protectionafforded by patches over the upper body and elsewhere, and the understoryand trees of its homerange. Indeed, he reportsthat among the flight feathers only one a similarly afflicted female cardinal observed by tertial was white, and in the tail only the two Hartman (1968) i n a much m ore o pen habitat innermostleft rectrices. Regrettably,this pattern succumbed to predation three months after it was does not provideany informationabout the age of first seen. the bird because it is consistent with the known feather replacementpattern during a first as well ACKNOWLEDGMENTS as a subsequentprebasic molt (Pyle1997). I am grateful for the helpful comments I received The other observation of a Song S parrowwas from Drs. L. Jenni, R. Leberman, P. Pyle, U. M. reportedby Johnson (2001) from a bandingstation Sayalii, and R. P Yunick, and I thank Dr. Anne B. locatedon Virginia'seastern shore. He captured Thistle for suggestingimprovements of the text. I a returningleucistic bird in 2000 that he had banded also acknowledge the permission received from as a normal-plumagedfirst-year individual in 1999. Cellular One (now U.S. Cellular) to conductbird- Accordingto informationprovided by B. Johnson bandingactivities in the woodssurrounding their (pers. comm.),banding and recaptureoccurred in telecommunication tower. mid-November,and pigment abnormalitieswere noted on crown, cheeks, throat, lower breast, back, LITERATURE CITED rump, and underwings. Because Song Sparrows do not have a prealternate molt, and the individual Bowers, R.R., J. Lujan, A. Biboso,S. Kridel,and referredto by Johnsonhad essentiallycompleted C. Varkey 1994. Premature avian melano- its body molt on both capture dates, the leucistic cyte death due to low antioxidant levels of pattern must have developed during the second protection:fowl model for vitiligo. Pigment prebasic molt. Cell Res. 7:409-418.

In the literature, a partial absence of melanin Buckley,P. A. 1987. Mendeliangenes. Pp. 1-44, productionis typically treated as an inheritable in F. Cookeand P. A. Buckley(eds.) Avian geneticdisorder (e.g. by Harrison1985, Buckley genetics. a populationand ecological 1987), mainlyon the basis of data collectedfrom approach. Academic Press, London; caged birds. Aside from genetic disordersthat Orlando, FL. resultin an inabilityto producepigment-producing melanocytesover parts of the body,genetic defects Harrison,C. J. O. 1985. Plumage,abnormal. Pp. havebeen described that lead to a prematuredeath 472-474, in B. Campbelland E. Lack(eds.) ofexisting melanocytes as a resultof an inadequate A dictionaryof birds. Buteo Books, mechanismof protectionagainst oxygen radicals Vermillion, SD. (Bowers et al. 1994). The mere observationsof spontaneous occurrences of melanin loss as described here certainly do not allow any Oct - Dec 2003 NorthAmedcan Bird Bander Page 167 Harrison,J. M. 1969. Plumage, abnormaland Keith, R., B. Keith, and J. A. Craves. 1999. Juvenile aberrant. Pp. 643-646, in A. L. Thomson Gray Catbirdundergoes complete prebasic (ed.)A new dictionaryof birds. McGraw molt. N. Am. Bird Bander24:143-144. Hill, New York, NY. Pyle, P. 1997. Identificationguide to NorthAmerican Hartman, F. E. 1968. White-headed cardinal. Bird- birds. Part I, 732 pp. Slate Creek Press, Banding39:57. Bolinas, CA.

Johnson,B. 2001. Kiptopeke,passerine banding Root, O. M. 1944. Song Sparrowturning white station(contribution to AtlanticFlyway within a month. Auk 61:295. Review: Piedmont-CoastalPlain, Region IV, Fall 2000, C. S. Robbins, coordinator). Wolfenbarger, L. L. 1999. Red colorationof male N. Am. Bird Bander 26:121-123. Northern Cardinal correlates with mate qualityand territoryquality. Behav. EcoL 10:80-90. News, Notes, Comments

High Incidence of Avian Pox in avian pox. In this sample, 43 of the 44 birdswere Southeast Michigan, Fall 2003 hatching-year (HY) American Robins; the other was a HY Northern Cardinal. This represented Avian poxis a viraldisease which occurs worldwide 12.3% of the robinscaptured this fall, and 15.8% of and has been reported in at least 20 families of the HY robins. birds (Friend and Franson 2001). The common, cutaneous form ls characterized by warty, This fall was also the first time we have observed scabrous lesions on the bare parts of birds, pox lesionson bills. Of the 44 birds, 12 (27.3%) particularlythe feet, legs, and bill. Because other involvedthe bill,consisting of large,warty growths, diseases may present in a similar manner, a raw, bloodypatches where scabs had come off; or pathologicexamination is necessary to confirm bill deformities such as eroded patches and infectionby one of the avian poxviral strains (Van missingchunks that were likelythe resultof healed Riperet al. 2002). However,bird banders generally poxlesions. Four of the 12 had poxlesions only on categorizebirds with these very visiblelesions as the bill, eight had pox on both the bill and feet or having"avian pox," as I do in this paper. legs Of the other 44 birds, 32 (includingthe cardinal)had (lesionsonly on the feet or legs. Of the 24,636 birdshandled by the RougeRiver Bird Observatoryat the Universityof Michigan- Birdswith pox symptoms were capturedthrough- Dearborn (Wayne Co., MI) from August 1992 out the season, and thus must have included both through July 2003, only 17 (0.07%) showed locallynesting birds and migrants.Until 21 Sep, all evidence of avian pox. These 17 individuals growthswere crustyand friable,easily falling off, representedsix species:American Robin, Turdus sheddingpieces, or bleeding.At that point,some migratorius (6); Yellow Warbler, Dendroica birdswere capturedwith growths that appearedto petechia(3); Chipping Sparrow, Spizella passerina be healing.These growthswere reducedin size (1); White-throatedSparrow, Zonotrichia albicollis and less friable: the skin was regrowingover (1); NorthernCardinal, Cardinalis cardinalis (2); missingtoenails. By 26 Oct, birds were being and Red-wingedBlackbird, Agelaius phoeniceus capturedthat had no activegrowths, but evidence (4). of healedlesions. The lastbirds with crusty, active- appearinglesions were capturedon 1 Nov. In fall2003, incidence of avianpox was of greater frequency. From mid-Augustthrough early The cutaneousform of avianpox is notusually fatal November,44 of 2,426 birdshandled (1.8%) had unlessthe growthsinterfere with breathing, vision, Page168 NorthAmerican Bird Bander Vol 28 No 4