THE BREEDING BEHAVIOR of the PAINTED BUNTING in SOUTHERN OKLAHOMA by DAVID F
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BIRD-BANDING A JOURNAL OF ORNITHOLOGICAL INVESTICATION Vol. XXX January, 1959 No. 1. THE BREEDING BEHAVIOR OF THE PAINTED BUNTING IN SOUTHERN OKLAHOMA By DAVID F. PARMELEE The Painted Bunting (Passerinaciris) is so intimatelya part of the avifauna of southeasternUnited States that many ornithologistsare surprisedto find it as commonin more westernparts of its range [The A. O. U. Check-List (1957: 554) states that it breeds as far west as New Mexico, Texas,and parts of Mexico]. In south-centralOklahoma it is amongthe very commonestof passerinebirds. Its great abundance in MarshallCounty near the north shoreof Lake Texomahas been well knownto investigatorsworking at the Universityof OklahomaBiological Station sinceits establishmentthere in 1950. This study dealschiefly with the populationof Painted Buntingson or near the station from June 15 to August 9, 1957. The original plan was to determine whether the subadult male of the speciesbred. In 1957, the number of subadultmales in the popu- lation observedwas very small. The numberof fully adult males,on the otherhand, was unexpectedly high. Consequently,the projectchanged to oneconcerned with the breedingbehavior of adult buntings,parti- cularlywith the role playedby eachsex at the nestand in careof young. The project startedtoo late in the seasonto includespring arrival of the buntings. Records(Baumgartner and Howell, 1947: 58; Nice, 1931: 176; Norman, unpubl. notes; Sutton, unpubl. notes) show that the speciesarrives at Oklahoma in late April. The earliest known arrival date.of April 17 is for CusterCounty, located west-centrally in the state (Nice, ibid.). The earliestarrival date for Marshall County is April 19; but apparentlythe speciesdoes not arrive there in force until the very last of April and the first of May (Sutton, ibid.). It is not certain which sex arrives first, or if the sexes arrive simul- taneously. Many April records are of singing males. The earliest knownarrival date of a femaleis April 30 (Sutton,ibid.), this having been recordedfor ClevelandCounty in the central part of the state. Earlier arrival dates may have been of either females or subadult males in female-likeplumage. Territorial disputesoccurred as early as May 5 in ClevelandCounty (Sutton, ibid.), and a full clutch of eggswas found as early as May 23 in MuskogeeCounty in northeast Oklahomaf Norman, ibid.). In SouthCarolina, male PaintedBuntings "alwayscome first, followed in about a week by the females" f Sprunt and Chamberlain, 1949: 515). In 1957, nestingof the Painted Buntingin Marshall County was well under way 'by mid-June. However, some early phasesof the breedingcycle, e.g., courtshipand nest construction,were continued 2] Parmelee,PAINTED BUNTING IN OKLAHOMA Bird-BandingJanuary eveninto July. This repetitionwas due in part to excessivepredation causedby floodwaters which concentrated predators, and in part to double-broodedness.We neverdid see,or interpretas such,the actual establishmentof a nestterritory--the nesting area defendedby the male againstother males of the species. Those that had been estab- lishedearly in the seasonapparently were maintaineduntil the end of nesting. The first egg of a clutch was found June 9 on the station grounds(by D. H. Baepler). A juvenileestimated to be 23 daysold was collectedseveral miles northwestof the stationon June 24, indi- cating that egg-layingstarted sometimein mid-May. Except for a femaleseen leaving an inaccessiblenest that possiblyhad eggsor young during May 26-28 f Sutton,ibid.), there are no earlier datesof egg- laying for any year in Marshall County, so far as known. We foundthe PaintedBunting common in scatteredstrips of wood- land betweenopen or partially overgrownfields, and along wooded, oftenvery deepgullies that led to Lake Texoma. Thinly woodedfringe along county roads was also favored by the buntings. There male after male on territory sang from telephonewires and tree perches closeto the road. Buntingswere lessnumerous in the larger groves and forestedareas where their numbersnoticeably decreased from the forest ecotoneto the denseinterior. They thrived in primarily agriculturalareas where some land was feral; in this respectrecently abandonedfarms providedoptimal conditions. This was not always so. Two pairsof buntingseven invaded the stationgrounds where large buildingsand extensivekept lawnswith exotic shrubscreated a pro- nouncedartificial environment. In all these habitats only the Mock- ingbird (Mimus polyglottos),Orchard Oriole (Icterus spurius),Brown- headed Cowbird (Molothrus ater), Cardinal (Richmondenacardinalis), and Lark Sparrow(Chondestes g'rammacus) appeared to .beas common as the bunting. Nest territories invariably had severalthings in cmnmon,namely: (1) enoughvegetation, though it be but a singletree or small bush, to supportand concealthe nest; {2) severalsinging perches for the male; t3) a feeding ground, usually a grassy field with scattered shrubs(see Fig. 1). We determinedterritorial boundariesby plotting pointswhere skirmishesbetween males took place, and by employing dummymales which were attackedunhesitatingly by defendingmales on territory. One carefully studied territory was 75 by 180 yards, somewhatrectangular in shape. Severaloth½•r territories studied were about this size. They also appearedrectangular in shape,perhaps a resultof the artificial sectioningof the land by roads,groves, fields, etc. At no time weretrespassing males tolerated. Disputes.were common, and there was much chasingby males; but displaysclosely resembling courtshipdisplays also took place. Malesapproached within inchesof each other, and sometimesone of them assumeda peculiar,very stiff stance,thrusting his head up and back and his tail up and forward. Then he flutteredhis wings,at times violently; often he kept his bill wide open. Aboveground this posturewas maintained even vertically --with front end down. Holding fast to his perch, he leaned far forward,parrot-like, toward his adversary,followed by viciousattacks. At timestwo birds facedeach other with openbills, and suddenlythey Vol. XXX 1959 Parmelee,PAINTED BUNTING IN OKLAHOMA spiraledstraight up from the ground for severalfeet, dealing blows the whole while. No cripplesresulted from the skirmisheswe wit- nessed;but there can be no doubt that real animosityexisted. Many timesthe dummywas struck hard by irate males. Havingfirst knocked the dummyfrom its perch,some males even followed it to the ground and attackedagain. One dummywas thus literally defeatheredand picked apart. The over-allshape of the species,the variouspostures it assumes whileperching, and its movementsin generalprobably evoke little or no response,other than t.o call attention,in maleson territory. The dummies.were flat, shapeless,simply cotton rilled skins. Regardlessof how placed, even upside down, they were attackedunhesitatingly. Moreover, the dummieswere motionless. Col,ors, more likely com- binationsof colors,probably elicited the responses,but we failed to isolatewhich colors were indispensable. The buntingsdid not attack cards.of a singlecolor or combinationsof .coloredcards, and for this reasonsome depth or shape,within limits, seemedimportant. Very noticeable.were the .brighteye-rings of the maleswhen they displayed beforeeither sex. At suchtimes these leathers a, ppeared elevated. We did not, however,experiment specifically with the eye-ring. The dum- mies were invariablyattacked by defendingmales, and usuallyre- peatedly. Sometimesthe dummieswent unseenby the males for Fig. 1. Painted Bunting .habitat in southern Oklahoma. Adult buntings on territory commonlygather insectsfor their young in feral fields such as shown in this picture. PhotographedAugust 9, 1957, by Donald H. Baepler. 4] Petrmelee,PAINTED BUN'TING IN OKLAHOMA Bird-BandingJanuary considerableperiods. This was especiallytrue, interestinglyenough, whenthe dummywas placedwithin a few feet of the nest. Only .oncedid we seea femaleattack an adult male, dummyor other- wise. This happenedwhen a dummywas placednear her nest with largeyoung. Bothshe and her matetogether repeatedly attacked the dummyabove and on the ground. Whenthe dummywas replaced with a subadultmale dummy,the male parent was much interested,ap- proachedit closelyfrom the side,above, and below,but did not fly at and strike it. The femalelikewise looked it over carefully,then sud- denlystiffened, fluttered her wings,and struckwith full fury. Only then did the male join the attack. We succededin trappingadult malesonly by baiting a live trap with otheradult males, either genuine or dummy. On the otherhand, we succeededin trappingfemales only by baiting with a fledgling. Our useof mist netswas not at all effectivein catchingbuntings of eithersex. Trappingactivities and field observations,use of bothlive and dummybirds, convinced us that trespassingmales were attacked by males,seldom by females,and that trespassing females were tolerated by both sexes,even in the nest-treeitself. Sincewe did not possess live subadultmales, we did not reach any satisfactoryconclusion con- cerning them. Onlyonce did we seea buntingchase another species of bird on or offterritory. In thiscase, a malestruck and drove off a DownyWood- pecker(Dendrocopos pubescens) that hadalighted near the bunting's nest.Only once did we see another species--a Great Crested Flycatcher (Myiarchuscrinitus)--chase a bunting. The MourningDove (Zen- aiduramacroura), Yellow-billed Cuckoo (Coccyzus americanus), Scis- sor-tailedFlycatcher (Muscivora ltorficata), Mockingbird, Brown Thrasher(Toxostoma rultum), Bell's