COWLES,Observations onthe Amethyst . [Jan.[Auk

OBSERVATIONS ON THE AMETHYST SUNBIRD, AMETHYSTINA AMETHYSTINA (SHAW).

BY RAYMOND B. COWLES.

The followingobservations were recordedin the Umzubi Valley, Natal, where this speciesis known by the Zulus as i' nCwincwi elimnyama. This is probablythe most commonSunbird in the thorn-bushassociation and is found frequentingthe openglades and edgesof the bush. It is not ordinarilyfound in the bushitself, but seemsto preferopen territory rather than the dense cover. While feedingon their favorite sourceof nectar, the blossomsof the umSinsi(Erythrina caffra) the maleis at timesvery conspicuousand makes a splendidcontrast, jet black againstscarlet blossoms, but at times they appearto vanishmysteriously and yet with carefulsearching will be re- vealednot far from the spot wherethey had beenperched a minute before. A possibleexplanation of this variation in visibility may lie in the 's proximityto shadowsof the blossomclusters or of the larger branches. Certainly,when looking upwards against the dazzlingsky of winter, shad- ows under the blossomsand lower surfacesof the branchesappear to be black. It would be interestingto make observationson the visibility of the speciesas seen from abovewith the sourceof illuminationbehind one. A note made while observingthese in an uHluzi tree in full bloom (a treewhich bears its blossomsin the shadeclose to the trunk andwhich thereforepresents a differentillumination and environment)indicates that while in the uHluzl tree the dull coloredfemales were inconspicuousbut the jet black maleswere very conspicuouscontrasting wonderfully with the red blossoms. The followingobservations of courtshipand nest building may be of value. The nest describedin the followingparagraphs, was located within six feet of a window near a table at which about sevenhours per day were spentskinning specimens and writing. An amethystSunbird was observedgoing through courtship antics in June,four monthsbefore the nestingtook place,for nestingdoes not take placeuntil September.Apparently the anticsare a carry-overand become play. The malewas hopping about on a branchnear a female,drooping first onewing then the other then both wingsat once. As eachwing was lowered,it was flutteredand displayed. The female,in the meantime,ap- pearedinterested and at onestage was seen to hanghead downward, in a stiff and rigid posture,without any perceptiblemovement. The same courtshipantics may be observedduring the breedingseason. Vol.lOS6 I.,III] .I Cow•rs,Observations onthe Amethyst Sunbird. 29

Early in Septembera pair of Amethyst Sunbirdswere seenbehaving as though they were hunting for nestingmaterials and a large wad of cotton wool was hung on an iron rod dependingfrom the (stoep)porch roof. By September7 the cottonhad beencarefully plastered over with liehens,and on the eveningof the sameday, after a day of work, a doorwaywas beginning to showwith a visor cominginto evidenee. Asidefrom this doorwaythere was no other sign as to which was back or front of the nest, the rest of the masswas simply a wad of eotton-wooljust as it had beenwhen first placed in position except that the surfacehad been coveredas previouslymen- tioned. The bird commencedwork at approximately10:00 a.m. and left work at approximately3:00 p.m. Thesehours were regularly observedduring most of the nest building activities. On September15 the male appearedfor the first time sincethe selection of the nestingsite. (During the selectionhe had beenexceedingly attentive and solicitousalthough most of the attention was directed toward his mate rather than toward work.) For an hour or so the male made sporadie attempts to interest his mate, and then having made no headway he ap- pearedto give up and did not return again until twelve days later. The femalewas hard at work, still makingover the doorway. Fourteenvisits were made in the eourseof an hour although twelve of them were made during one twenty-five minute period. On September16 someprogress had beenmade and the back and bodyof the nest were being fashioned. The bird would alight on the floor of the entranceand from that positiontuck in and pull out parts of the nestin the processof mendingand shaping,and from time to time sheentered the nest in orderto wrigglearound and aroundas thoughtesting for size,at the same time shestretched the nest here and there to make a goodfit. At one time after someparticularly vigorous efforts she sat still for a moment,head out, and snuggleddown as though making still another test. The doorwayfaced away from the light and toward the walls of the house. It wouldbe interestingto note the relative positionof other nestopenings of this speciesin relation to light and shelter. Sofar as an observercan tell, the nest couldhave beenplaced facing in any other direetionwith equally satisfactory results. By September19 the nest was fairly well along in constructionand the porchor visorseemed at last finishedand satisfactoryand the lining of the nestwas begun. From the abovedate until September27 onlya few visitswere paid to the nest but on this date both birds made a visit and while the female entered and erouchedin the nest the male dung to the entrance,billing the female affeetionately. On this visit the femalebrought some downy substance for 30 Cow•,Es,Observations onthe Amethyst Sunbird. lankFJ•n. lining the nest but the activities seemedperfunctory or merely a continu- ance of habit. (A nest watchedthe previousyear showedthat the same thing happened,i.e., after completionof the nest the birds left for two or three days scarcelycoming near the spot, and then returned, being much more shy followingthe rest period.) The occurrenceof the rest period and subsequentshyness fits into the generalpattern of bird behaviorin nesting,bold when incubationis pro- gressing,shy during hatching, bold when all the young are hatched and growing,shyness when younghave reachedindependence. On September28 a few visits were made, each time earwing down for lining purposesalthough the nest was already thick and warm. The next day, September29, the first eggwas laid and that night the femaleslept in the nestfor the secondtime. At about 8:00 a.m. a secondegg was laid. The female remained in the nest most of the time during the day and alwaysat night until October3, invariably with the bill restingon the rim of the porchand projectingjust beyondthe outermostmargin of the visor. On the night of the third, she did not sleepin the nest, and was absent all day on the fourth, and most of the day on the fifth. On that day shear- rived at 3:30 p.m., remaininguntil 5:30 p.m. and left. again not to return. The nest had been carefully protectedfrom handling or closeapproach and care had been taken not to disturb the birds, but for severaldays before deserting she had been unsettled and nervous. The following accountby an untrained observer(Mr. F. B. Cowles) was at first consideredby the writer to be a misinterpretation of an in- terestingfeeding habit but sincehis experiencewith the cotton ball he is less doubtful although he still wishesto seethe performancewith his own eyes,or seea report from a trained observer. The report is as follows: "In certain tall mimosa trees which grow rather commonlythroughout this section a certain spiderbuilds a large globular'nest.' This is attached to the end of a long slender branch. At a period when the spiderlingsare about the sizeof the head of a pin, the male Sunbirdattacks and kills what is apparently the parent spider (?) and makesan openingin the side of the nest. This openingis about an inch in diameter. During the attack and openingof the nest only the male bird was seen,later the female appearedand for three weeksor so the pair were constantlyin the vicinity, the male most frequently." These observations led the observer to believe that the birds had taken the spider'snest and convertedit to their ownuse. During part of this time the nestwas swarming with youngspiderlings "and the Sunbirdswere seen feedingon them and entering the nest. The nest was allowedto remain unmolestedand the eggswere never seen." Universityof Californiaat Los Angeles.