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Physiol. 82:781-785. WILSON, R. P., G. D. LA COCK, M.-P. WILSON, AND F. WARNER, A. C. 1981. Rate of passagethrough the gut MOLLAGEE. 1985. Differential digestion of fish and of mammals and . Commonw. Bur. Nutr., Nutr. squidin JackassPenguins Spheniscus demersus. Omis Abstr. Rev. Ser. ‘B’ 51:789-820. Stand. 1677-79. WILSON, R. P. 1984. A wet off-loading stomach pump for penguinsand other seabirds.J. Field Omithol. 55: 109-111.

The Condor 88:119-120 0 The Cooper Ornithological Society 1986

GALAPAGOS MOCKINGBIRD IUEPTOPARASITIZES CENTIPEDE ’

ROBERT L. CURRY Division of Biological Sciences,University of Michigan, Ann Arbor. Michigan 48109 USA

Key words: Galapagos;mockingbirds; Mimidae; Ne- This is a clear but isolated case of kleptoparasitismby somimus; centipedes;Scolopendra; kleptoparasitism; op- a mockingbird. It is the only observationof its kind I have portunisticforaging. made in Galapagos,though I spent 20 months studying mockingbirdsbetween 1981 and 1985. I know of no pre- Kleptoparasitism of arthropods by birds is rare. In a re- vious reports of kleptoparasitismby mockingbirds in the view of kleptoparasitismin birds, Brockman and Barnard islands. (1979) cited two examplesinvolving arthropod hosts:ant- Why isn’t kleptoparasitismof centipedesby Galapagos birds occasionallysteal prey from tropical army ants; and mockingbirds more common? Opportunistic behavior a few North American land birds, especiallyHouse Finch- shouldfacilitate the of kleptoparasitism(Brock- es (Carpodacusmexicanus; Brockman 1980), sometimes man and Barnard 1979), and the four speciesof Galapagos kleptoparasitize digger wasps. Here I describe an addi- mockingbirds(Nesomimus spp.) are certainly opportunis- tional example of a kleptoparasitizingan arthropod. tic. Throughout the archipelagomockingbirds have broad In this instance, a Galapagos mockingbird, Nesomimus diets that include many different foods including parvulus, stole food from a Galapagoscentipede, Scolo- insects,lizards, carrion, feces,seabird regurgitate, and sea- pendra galapagaea. bird eggs(Bowman and Carter 197l), morselspicked from I made the following observations on Isla Genovesa, the teeth of sleeping sea lions (Zalophus californianus) Galapagos,during my research on cooperative breeding (Trimble 1976) and, on some islands, ticks and live skin in Galapagosmockingbirds (see Kinnaird and Grant 1982; pulled from land iguanas(Conolophus subcristatus and C. Curry, in press). While making a routine census of the pallidus) (Christian 1980). Espafiola Mockingbirds (N. study area on 9 January 1985, I encountered a banded macdonaldi)even feed on blood from live marine iguanas adult mockingbird that was inspecting shallow crevices (Amblyrhyncuscristatus), sea lions, and seabird chicks betweenflat platesof lava that covered the ground. Shortly (Currv and Anderson. in vrev.). The incident described after I found the bird, it stopped foraging and walked to above is an additional example’of a Galapagosmocking- the edge of a narrow crevice where a centipede about 20 bird opportunisticallyexploiting another animal, yet klep- cm long was moving in the litter. The mockingbird stood toparasitism of this kind occursonly rarely. motionless watching the centipede for 20 set and then Four factors are probably involved in preventing klep- suddenlythrust its head into the crevice. It withdrew im- toparasitismofcentipedes by Galapagosmockingbirds from mediately holding in its bill a large wingless cricket that becoming more common. had either been flushed or capturedby the centipede.The 1) Mockingbirds seldom interact with centipedes.Cen- bird jumped upward, avoiding the head of the centipede tipedesare neither abundantnor gregariousin the habitats which partially emergedfrom the crevice,and backedaway where I studied, and they are primarily nocturnal. When a few meters. The centipede immediately resumed for- centipedesare active during daylight hours they tend to aging in the crevice. remain hidden under lava plates.Encounter rates are prob- The mockingbird ate the cricket and returned to its po- ably low enough to prevent mockingbirds from special- sition above the crevice. After staring downward for 60 izing as centipedekleptoparasites even though large crick- set, the mockingbird again reached into the crevice. This ets, such as those I saw taken from the centipede, are time I saw it take another large cricket directly from the valuable food items that are readily eaten by adult mock- centipede’s mouthparts. The centipedecrawled complete- ingbirds or fed to nestlings. ly out of the crevice and approachedthe mockingbird; the 2) Centipedes are valuable mockingbird prey. When a bird jumped back with its wings raisedand retreated.After mockingbird finds a centipede, it usually tries to eat it the bird had moved off about 3 m, the centipede returned rather than attempting to kleptoparasitizeit. I frequently to the crevice. The mockingbird spent 3 min eating this saw mockingbirds, sometimes in groups, attack and kill cricket and then returned to the crevice at the point where centipedeson Genovesa,Espailola, and Champion, and I I had last seenthe centipede.The bird waited at the crevice saw them feed small centipedesto nestlingson Genovesa 70 set and then walked away, resuming normal foraging; and on Santa Cruz. Bowman and Carter (197 1) also saw it did not searchfurther for the centipede. mockingbordseat centipedeson Darwin and Santa Cruz. Occasional kleptoparasitism of centipedes by mocking- birds, then, has probably derived from predation (Brock- * Received 8 August 1985. Final acceptance30 Septem- man and Barnard 1979). ber 1985. 3) Most centipedesare small. These are probably unable 120 SHORT COMMUNICATIONS

to capture prey that a mockingbird would steal in pref- lfipagosNational Park Service for permission to conduct erence to eating the centipede itself. Only on those rare this research.The CharlesDarwin ResearchStation helped occasionswhen a mockingbird meets a large centipede with logistics.Financial supportwas provided by the World does kleptoparasitismbecome a potentially profitable al- Wildlife Fund-U.S.. the Frank M. ChaDman Memorial ternative to predation. Not only are large centipedesca- Fund, the Universiiy of Michigan, and aNatural Science pable of capturing prey worth stealing, but they are also and EngineeringResearch Council ofcanada postgraduate difficult to eat; mockingbirdscan break off and eat the legs scholarship.I carried out my researchin conjunction with of large centipedes,but are seldom able to kill them. P. R. Grant’s studiesof Galapagosland birds, and I thank 4) Interactionwith largecentipedes may be risky. Though him and his coworkers for advice and assistanceduring mockingbirds readily eat even very large centipedesthat all phasesof my project. are dead, they are exceedingly cautious when attacking largeliving centipedes.In contrast,I saw Short-earedOwls (Asioflammeus)and Yellow-crowned Night-Herons (Nyc- LITERATURE CITED tanassa violuceu)eat large centipedeswithout hesitation. At least four banded mockingbirdsin the Genovesa study BOWMAN,R. I., AND A. CARTER. 1971. Egg-peckingbe- area may have been killed by centipedes; I found their havior in Galapagos mockingbirds. Living Bird 10: intact carcassesin the same kinds of creviceswhere I most 243-270. often saw centipedes and where the incident described BORCKMAN,H. J. 1980. House Sparrowskleptoparasitize above took place.(Owls are the only other significantpred- digger wasps. Wilson Bull. 92:394-398. ator of mockingbirds on Genovesa and they usually dis- BROCKMAN,H. J., AND C. J. BARNARD. 1979. Klepto- member their kills.) Individual N. parvulusweigh roughly parasitism in birds. Anim. Behav. 27:487-5 14. 50 g; the largest centipede I measured on Genovesa was CLOUDSLEY-THOMPSON,J. L. 1958. Spiders, scorpions, roughly 30 cm long and weighed23 g. Smaller Scolopendru centipedesand mites. Pergamon, London. centipedesin other regions-cankill mice and small birds CHRISTIAN,K. A. 1980. Cleaning/feeding symbiosisbe- (Cloudslev-Thomnson1958) and GalSnaaosresidents claim tween birds and reptiles of the GalfipagosIslands: new that Scolipendru&upugu~u can kill small dogs;they can observationsof inter-island variability. Auk 97:887- also inflict a painful bite that producessevere swelling in 889. humans (B. Bamett, pers. comm.). A mockingbird may CURRY,R. L. In press. Breeding and survival of Gal& risk its life if it interactswith a large centipede even if its pagos mockingbirds during El Niiio. In G. R. Rob- goal is kleptoparasitismrather than predation. inson and E. de1Pino [eds.], Galapagos 1982-1983: I suggestthat risk of injury or death, combined with a chronicle of the El Nifio. rarity of encountersbetween mockingbirdsand centipedes KINNAIRD,M. F., AND P. R. GRANT. 1982. Cooperative that are too large to eat, prevents kleptoparasitismof cen- breedingin the Galapagosmockingbird. Behav. Ecol. tipedes by Galgpagosmockingbirds from becoming more Sociobiol. 10:65-73. common. TRIMBLE,S. A. 1976. GalSlpagosmockingbird pecks at I thank Superintendent Miguel Cifuentes and the Ga- sea lion mouth. Condor 78:567.

The Condor 88:120-122 0 The Cooper Ornithological Society 1986

THE SYSTEMATIC STATUS OF CRANIOLEUCA FURCATA TACZANOWSKI (FURNARIIDAE)’

GARY R. GRAVES Department of VertebrateZoology, National Museum of Natural History, SmithsonianInstitution, Washington,D.C. 20560 USA

Key words: Cranioleuca; furcata; spinetail; curtata; ion. Meyer de Schauensee(1966) gavefurcata a full entry, Andes;Tuczanowski; Furnuriidue. but stated “from the description one would suspectthis to be the young of curtutu.” Later, he (Meyer de Schauen- Taczanowski (1882) described Cranioleucufurcuta from see 1970) omitted any referenceto C. furcutu in his guide two specimens collected by Sztolcman (=Stolzmann) at to South American birds. Chirimoto (1.646 m), Dnto. Amazonas. Peru. The validitv Vaurie (197 1, 1980) examined the single surviving co- of the specie; remained-unquestionedfor nearly 60 years, type, in the Instytut Zoologicznyof Warsaw and concluded probably due in part to the relative inaccessibilityof the thatfurcutu was a valid .Following his examination type specimenand the lack of comparative material from of the Warsaw specimen, Vaurie (1971) identified three the Andes. Without examining the type, Bond (1945) con- “ochraceous” immature specimensof Cranioleucuin the sideredfurcutu to “probably be the immature” of the Ash- “abajo chaco,” Rio Oyacachi (ca. 1,500-2,000 m) on the browedSpinetail (Crunioleucu curtatu; Sclater 1869), which easternslope of the Ecuadorian Andes. A third specimen rangesfrom Colombia alongthe easternslope of the Andes identified by Vaurie as belongingto C. furcutu was taken to central Bolivia (Parkes, unpubl.). Peters (1951) listed at Chaupe (1,860 m), Dpto. Cajamarca, northern Peru furcata as a species,but with a query, citing Bond’s opin- (AMNH 181344). These specimenshad been included by Chapman (1924) in the type series of C. curtutu “grisei- pectus” (=C. curtutu cisandinu). The Chaupe specimen was subsequentlyidentified as C. curtatucisundinu (Bond I Received 1 April 1985. Final acceptance21 August 1945). 1985. Although Morony et al. (1975) adopted Vaurie’s (1980)