This is the first account of vampire bats (Desrnodus rotundus) preying ... of blood each night that amounts to over 50 % of the fasting mass of the bat, or ca.
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Eine Beziehung zwischen Explorationsverhatten und Lebensraumanspriichen scheint also bei den Papageien zu bestehen. Vertiefende Untersuchungen werden zur Zeit an Loris (Loriini) und Plattschweifsittichen (Platycercini) durchgefiihrt. Literatur ALTMANN, J. (1974): Observational study of behaviour: sampling methods. Behav. 49: 227--265. BAt~N~TT, S. A. (1958): Exploratory Behaviour. Brit. J. Psychol. 49: 289-310. • BELL, H. L. (1966): Some feeding habits of the Rainbow Lorikeet. Emu 66: 71--72. • BLONDZ~,J. (1985): Habitat selection in island versus mainland birds. In: M. L. COPY, Habitat selection in birds: 477--516. N. Y. • BOE~M, E. E (1959): Parrots and cockatoos of the mount mary plains, South Australia. Emu 59: 83--87. GLICKMANN,S. E., & R. W. SP,OGES(1966): Curiosity in zoo animals. Behav. 26: 151--158. • GOULD, J. P. (1974): Risk, stochastic preferences, and the value of information. J. Econ. theory 8: 64--84. HaEMIG, P. D. (1989): A comparative experimental study of exploratory behaviour in Santa Cruz island and mainland California scrub jays (Aphelocorna coerulescens).Bird Behaviour 8: 38--42. • HI,wOOD, K. A., & M. SHARLaNI)(1964): The Swift Parrot. Emu 63: 310--326. LEISLER,B., & H. WrNKL~R(1990): The function of exploratory behaviour in birds. Acta 20. Congr. Int. Orn.: 404. SIBL~Y, C. G., & J. E. AHLQUIST(1990): Phylogeny and classification of birds. New Haven u. London.
Penguins bled by vampires Guillermo Luna-Jorquera and Boris M. Culik
LUNA-JORQUERA,G., C~5HK, B. M. (1995): P e n g u i n s bled by v a m p i r e s . J. Orn. 136: 471-472. - Penguins have a variety of ennemies both on on land and at sea. This is the first account of vampire bats (Desrnodusrotundus) preying on juvenile Humboldt Penguins (Spheniscushurnboldti). Because , f the nightly drain of blood by vampires, and because vampires transmit diseases from one prey species to another, this form of predation may be an important mortality factor. Institut fiir Meereskunde, Diisternbrooker Weg 20, D-24105 Kiel, Germany The Humboldt Penguin (Spheniscushumboldti), endemic to the area influenced by the cold, nutrient-rich Humboldt Current and breeding on the mainland coast and offshore islands of Peru and Chile between Isla Foca (5 o S) and Algarrobo (33 ° S) is listed as endangered (CITES Appendix 1 Species) with the population estimated at ca. 10,000 birds in 1987. Its population decline has been attributed to the collapse of anchoveta (Engraulis spec.) stocks through overfishing, incidental catches in gill nets, and human disturbance (D~FY et al. 1984, HAYS 1984). Mortality is also caused by natural predators such as killer whales (Orcinus orca), sharks (Char-
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carodon charcarias) and fur seals (Arctocephalus austral#) at sea, and desert foxes (Dusicyon sechurae), Peruvian Gulls (Larus belcheri) and Kelp Gulls (Larus dominicanus) on land (WIlLiAMS 1995). We would like to report here on a further form of predation on Humboldt Penguins described as "micro predation". Micro predators prey on several different hosts or the same host at several discrete times (ScH~aII)T& ROBERTS1989). The micro predator, however, does not kill its host. While studying Humboldt Penguins at Isla Pan de Azucar (26 o S) we observed a nest with two chicks, 3 and 1 week old, for 24 h. At 22:00 we noted nocturnal activity beginning in vampire bats Desmodus rotundus. When checking the penguin burrow at 24:00 we observed a vampire bat which was just abandonning one of the penguin chicks. Inspection of the chick revealed two small cuts in one of the legs on the tarsometatarsus, just below the feathers. Although there has recently been a detailed description of external penguin parasites (CLAraCE & Ket~RY 1993), this is the first report of Desmodus preying on a penguin. The vampire bat is the only chilean chiropteran species which feeds solely on blood. The species has been reported to prey on mammals, i. e cows, horses or mules by climbing up the foreleg to the shoulder or neck and making an incision several millimetres deep using its upper incisors and canines. Blood from the wound is then lapped by the tongue Occasionally, however, vampires feed on the feet of cattle It has been estimated that each bat takes a meal of blood each night that amounts to over 50 % of the fasting mass of the bat, or ca. 18 g in a 34 g bat (VAuGHAN 1978). To date, these bats were not known to also prey on birds. Other vampire prey at Isla Pan de Azucar and the nearby mainland possibly includes otariids Otaria flavescens, guanacos Lama guanicoe and other species of seabirds. During a subsequent inspection of the island we found a cave which was used by 12 individuals of D. rotundus sleeping 4 m above the ground. Because of the nightly drain of blood by vampires, and because vampires transmit diseases (VAuGHAN 1978) from one prey species to another, these bats may be an important mortality factor in Humboldt Penguins. The importance of this awaits further investigation. Zusammenfassung Pinguine haben eine Vielzahl von Feinden, sowohl im Wasser als auch an Land. Dies ist der erste Hinweis darauf, dab Vampirflederm~use (Desmodus rotundus) sich vom Blut yon Humboldtpinguinkiiken (Spheniscus humboldti) ern~ihren. Wegen der n~chtlichen Blutverluste durch Vampirflederm~iuse, und well diese Blutsauger Krankheitserreger zwischen ihren Wirten iibertragen k6nnen, k6nnte diese Form des Parasitismus einen wichtigen Mortalit~itsfaktor darstellen. Literature C L A ~ , J. R., & K. R. KE~Y (1993): Diseases and parasites of penguins. Kor. J. Polar. Res. 4: 79--96. DurFY, D. C., C. HAYS & M. A. PLaNer (1984): The conservation status of Peruvian seabirds. In: J. P. CI~OXALL,E G. H. EVANS& R. W. SCH~iBER, Status and conservation of the world's seabirds: 245--259. ICBP Tech. Publ. 2; Cambridge. HAYS, C. (1984): The Humboldt Penguin in Peru. Oryx 18: 92--95. SCHMIDT, G. D., & L. S. ROB~R~ (1989): Foundations of parasitology: 8--9. St. Louis. VAUOHAN, T. A. (1978): Mamm~logy: 123--124. Philadelphia. WILLIAMS,T. D. (1995): The Penguins. Oxford.
