Short Communications The Wilson Journal of Ornithology 118(1):99±101, 2006 Provisioning of Fledgling Conspeci®cs by Males of the Brood-parasitic Cuckoos Chrysococcyx klaas and C. caprius Irby J. Lovette,1,4 Dustin R. Rubenstein,1,2,3 and Wilson Nderitu Watetu3 ABSTRACT.ÐAlthough post-¯edging care by adult Over the past century, there have been nu- males seems unlikely in bird species that are obligate, merous observations of male Chrysococcyx interspeci®c brood parasites, there have been numer- cuckoos feeding conspeci®cs that were ous reports of adult male Chrysococcyx cuckoos ap- parently feeding conspeci®c young. Most researchers thought to be ¯edglings (Moreau 1944, Fried- currently view these observations with skepticism, in mann 1968, Iversen and Hill 1983, Rowan large part because Chrysococcyx and other cuckoo spe- 1983). In a literature review of provisioning cies engage in courtship feeding, and it is possible that behavior in brood parasites, Lorenzana and ®eld observers could mistake adult females receiving Sealy (1998) found 5 records of nestling or food from courting males for ¯edglings, especially giv- en the similar appearances of females and juveniles. ¯edgling provisioning by Klaas's Cuckoo Here, we report an observation of an extended provi- males and 11 such records for Diederik Cuck- sioning bout by an adult male Klaas's Cuckoo (C. oo males; Friedmann (1968) discusses 12 and klaas) feeding a conspeci®c individual with juvenile 15 such records, respectively, including some plumage and behavior, and we summarize our obser- anecdotal reports. There is apparently only vations of similar occurrences in the Diederik Cuckoo one equivalent report of a female Chrysococ- (C. caprius) in Kenya. We suggest that the available evidence indicates that male provisioning, and hence cyx cuckoo provisioning ¯edglings, and in that potential parental care, is present in these brood-para- case, both the female and young were captive sitic cuckoos at a higher frequency than currently rec- birds (Millar 1926, Lorenzana and Sealy ognized. The mechanism that causes males to associate 1998). Historically, a number of researchers with ¯edglings is unknown, but warrants further study. (e.g., Moreau 1944, Friedmann 1968) consid- Received 20 December 2004, accepted 19 September 2005. ered parental care to be common in African Chrysococcyx cuckoos and believed that the behavior might be a primitive condition as- sociated with a relatively recent evolutionary The genus Chrysococcyx comprises 15 spe- transition to brood parasitism. As researchers cies of small, Old World cuckoos (Sibley and continued to document the prevalence of Monroe 1990), of which all are thought to be courtship feeding in these and other cuckoo obligate brood parasites (Davies 2000). species, more recent authorities (e.g., Rowan Klaas's Cuckoo (C. klaas) has a wide distri- 1983, Irwin 1988, Lorenzana and Sealy 1998, bution in sub-Saharan Africa, where it is Davies 2000) have suggested that the behavior known to parasitize a large number of passer- is either misdirected courtship feeding or the ine host taxa, oftenÐbut not exclusivelyÐ result of human observers misidentifying species of Sylviidae and Nectarinidae (Irwin adult females as ¯edglings. In practice, these 1988). Similarly, the Diederik Cuckoo (C. ca- and other possibilities are dif®cult to exclude. prius) breeds throughout much of sub-Saharan Although the plumages of adult African Chry- Africa and has a broad range of hosts, pri- sococcyx are highly sexually dimorphic, it is marily species of Ploceidae (Irwin 1988). dif®cult to distinguish females from juveniles in the ®eld (Rowan 1983). 1 Cornell Lab. of Ornithology, 159 Sapsucker Here, we report an observation of an ex- Woods Rd., Ithaca, NY 14850, USA. tended provisioning bout by an adult male 2 Dept. of Neurobiology and Behavior, Cornell Klaas's Cuckoo feeding a conspeci®c individ- Univ., Seeley G. Mudd Hall, Ithaca, NY 14853, USA. 3 Mpala Research Centre, Box 555, Nanyuki, Ken- ual with juvenal plumage and behavior, and ya. we summarize our observations of similar oc- 4 Corresponding author; e-mail: [email protected] currences in the Diederik Cuckoo. These ob- 99 100 THE WILSON JOURNAL OF ORNITHOLOGY x Vol. 118, No. 1, March 2006 servations add to the body of evidence sug- white patch behind the eye and a white throat gesting that male Chrysococcyx cuckoos may marked with substantial, dark barringÐplum- engage in intensive provisioning of juveniles. age characters more typical of juveniles (Irwin 1988). KLAAS'S CUCKOO Beginning at 10:08 UTC13 on 15 August DIEDERIK CUCKOO 2004, IJL, DRR, and WNW observed an adult On 28 May 2002 at 08:23, WNW observed male (by plumage) Klaas's Cuckoo in Lake a male Diederik Cuckoo feeding an apparent Nakuru National Park, Kenya (008 229 S, 368 ¯edgling (based on plumage) at the Mpala Re- 039 E). This bird was foraging at an extremely search Centre, Laikipia, Kenya (008 179 N, rapid rate of movement in the open canopy of 368 549 E). The ¯edgling was perched about 3 a large yellow-barked acacia tree (Acacia xan- m above ground in a Balanites aegyptica tree. thophloea). After watching the bird for a few During 15 min of observation, the adult fed minutes, we observed it deliver food to a sec- the ¯edgling at least four times and continued ond, sedentary cuckoo in the same tree. We to do so when the observer left the area. On noted the time, and for the next 26 min, we 19 May 2003 at 10:15, WNW noted similar were able to keep both cuckoos under constant behavior at a site 100 m from that of the ®rst focal observation with at least one observer observation. During this observation, an adult following each bird. This is apparently the male Diederik Cuckoo gleaned insects from longest-duration period of potential ¯edgling long grass and fed them to a ¯edgling (based provisioning reported for Chrysococcyx on plumage) perched on a nearby acacia. We (Friedmann 1968). observed the male make six feeding trips be- During our observation, the adult male fore cattle ¯ushed the birds. cuckoo continued to forage rapidly within an approximate 40-m radius around the second DISCUSSION cuckoo. The male returned to the second Based on the posture, behavior, and plum- cuckoo 18 times while carrying food items, age of the Klaas's Cuckoo that we observed all of which appeared to be 1- to 3-cm-long being fed by an adult male, it seems highly lepidopteran larvae gleaned from the foliage likely that it was a recently ¯edged bird rather and bark of the acacia. On 16 of the 18 visits, than an adult female being courted. We also the second, more sedentary bird accepted and noted that the adult male engaged in intensive ate the caterpillar. On each visit, the adult (and, presumably, energetically costly) forag- male presented the food with his tail slightly ing for an extended period in order to provi- cocked, but we observed no other conspicuous sion this individual. Friedmann (1968) consid- postures or behaviors potentially related to ered provisioning bouts as long as 15 min as courtship. No copulations or attempted copu- ``suggestive of the fact that the catering adult lations occurred. was not merely indulging in courtship feed- During our observation, the presumed ju- ing.'' Our observation of an intensive provi- venile moved among four perches, ¯ying 3±4 sioning period of nearly twice that duration m each time. These ¯ights were notably more further supports this interpretation. In contrast, ¯uttery than those of the adult male and ap- courtship feeding in Chrysococcyx typically peared typical of the weak ¯ight exhibited by involves a series of stereotyped behaviors that recently ¯edged birds. While perched, this we did not observe: the male's presentation of bird also assumed the ``¯uffed'' posture typi- food while simultaneously cocking his head cal of recent ¯edglings, and it remained sta- and vibrating his wings and tail, postural bow- tionary between most provisioning visits. The ing movements by the male, vocalizations by observation ended when the presumed juve- the male or both individuals, or (in some cas- nile made a similar, but slightly longer ¯ight es) subsequent copulation (Irwin 1988). into denser foliage and disappeared from our When considered in concert, our observa- sight. Although the plumages of female and tions and those in dozens of previous reports immature Klaas's Cuckoos are variable and describing equivalent behaviors suggest that overlap (Irwin 1988), we noted at the time males of several African Chrysococcyx cuck- that the bird being provisioned had a distinct oos may provision ¯edglings regularly. Post- SHORT COMMUNICATIONS 101 ¯edging associations of adults and offspring LITERATURE CITED also have been documented in other brood- parasitic taxa, such as the Brown-headed DAVIES, N. B. 2000. Cuckoos, cowbirds, and other cheats. T. & A.D. Poyser, London, United King- Cowbird (Molothrus ater; Hahn and Fleischer dom. 1995). Indeed, previous reports have docu- FRIEDMANN, H. 1968. The evolutionary history of the mented male Klaas's and Diederik cuckoos genus Chrysococcyx. U.S. National Museum Bul- provisioning both pre-volant young and mul- letin, no. 265, Smithsonian Institution, Washing- tiple ¯edglings (Moreau 1944, Friedmann ton, D.C. 1968, Lorenzana and Sealy 1998), thus ex- HAHN,D.C.AND R. C. FLEISCHER. 1995. DNA ®nger- print similarity between female and juvenile cluding misidenti®cation of adult females as Brown-headed Cowbirds trapped together. Animal suf®cient explanation for this behavior. We Behaviour 49:1577±1580. speculate that not only are females sometimes IRWIN, M. P. S. 1988. Order Cuculiformes. Pages 58± misidenti®ed as ¯edglings, but perhaps older 104 in Birds of Africa, vol. III (C. H. Fry, S. ¯edglings being provisioned by males are Keith, and E.