SPECIAL FEATURE

Birds of Madagascar

INTRODUCTION

Madagascar has been isolated from the African continent for about 160 million years. Since that time, well before the appearance of most modern , all have had to disperse to Madagascar across about 400 km of open sea. For all terrestrial animals, this has happened extremely rarely. Birds, being more mobile, have colonized more successfully and show a lower degree of endemism, than for example plants, reptiles and mammals, but still they exhibit a level of endemism that is unique in the world. The total of 283 (of which 209 breed regularly on the island) is much lower than continental avifaunas of comparable surface area, but the level of endemism, and the great dependence of those endemic species on forest habitats, make the Malagasy avifauna remarkable. Of the 209 breeding species, 51% are endemic to Madagascar. Only seven (3%) are seasonal visitors, all of them from Africa. Of these seven species, three breed only in Madagascar. Thus, Madagascar is renowned as a living for laboratory of evolution. All ornithologists and birdwatchers long to visit this island at least once. Twenty years ago, Satoshi Yamagishi (then at Osaka City University) became interested in the Vangidae. The family Vangidae is endemic to Madagascar and consists of 14 (Langrand 1990) or 19 species (Yamagishi et al. 2001). This family provides one of the most striking examples of adaptive radiation in the Madagascan avifauna, to an extent that is even more extreme than the better known examples of the endemic Galapagos finches (part of the family Emberizidae) or of the Hawaiian honeycreepers (which are considered only as a subfamily Drepanidinae of the Fringillidae). Yamagishi focused on the adaptive radiation of the Vangidae and in particular on the breeding system of the Rufous Schetba rufa. He received grants from Ministry of Education (Monbusho) and launched “The Vanga Project” with Kazuhiro Eguchi and many other young ornithologists. The project objective was to elucidate the “natural history of the ” from a comprehensive perspective, including its molecular biology, genetics, physiology, morphology, , phylogeny, population ecology, community ecology, ethnology, animal sociology, and evolutionary biology. This project, using a foreign country as its study site, was first of its kind in the history of Japanese Ornithology. The overall objective of the project was realized with the publication of the “Social Organization of the Rufous Vanga” in 2005 by Kyoto University Press (Yamagishi 2005). Here, I have gathered seven new papers for this special feature, all authored by members of The Vanga Project. The contents of these seven papers were not described in the publication “Social Organization of the Rufous Vanga”. In the first paper, Eguchi, Asia and Yamagishi describe their studies of the social breeding sys- tem of the Rufous Vanga. This species is a cooperative breeder in which a pair is accompanied by one or more helper males. The helper’s aid did not enhance reproductive success (Eguchi et al. 2002). They discussed the benefits derived by one-year old and older helpers. The first authors of the second, third and fourth papers, Nakamura and Rakotomanana, have studied the breeding biology of several vangid species. Yamagishi and Eguchi (1996) observed the foraging behavior of 13 vangid species, and documented the differences in their foraging niches. In contrast to what is known of their foraging ecology, very little is known about the breeding ecology of any of these species. In this special feature, they provide the first detailed information on the breed- ing ecology of Tylas eduardi, Chabert’s Vanga Leptopterus chabert, and Red-tailed Vanga madagascariensis. In the fifth paper, Mizuta describes his studies of the nest-site characteristics affecting the risk of nest preda- tion in the endemic Madagascar Paradise Flycatcher Terpsiphone mutata. The breeding success of birds on Madagascar, including Madagascar Paradise Flycatchers, is low. Since nest predation directly depresses lifetime fitness, it leads to the evolution of avian life-history traits. Mizuta investigated the time at which nest

1 Birds of Madagascar

Satoshi Yamagishi (second from the right) and Kazuhiro Eguchi (left), with Mark Pigeon and Sheila O’Connor, in a hotel at Berenty in 1989. predation occurred by using temperature data loggers attached to nests. He described why the identification of predators and discerning the time of nest predation are important when examining the nest-site characteristics affecting the risk of nest predation. In the sixth paper, Hino describes his research into the effects of seasonal- ity on the function of avian mixed-species flocks in Madagascar. Many species of vanga, Madagascar Paradise Flycatchers and various other species form mixed-species flocks both during the breeding and nonbreeding seasons. He discusses the different functions of avian mixed-species flocks between the breeding and non- breeding seasons. Hasegawa, the first author of the seventh paper, is a herpetologist and interested in the diet and foraging microhabitat overlap between insectivorous birds and lizards. He and his partners analyzed the guild structure of various vertebrates and they discuss the evolutionary consequences of competition and pre- dation on resource segregation among and between and lizard species. , along with other birds of Madagascar, are found in all forested habitats on Madagascar. They are conspicuous and regular members of mixed-species foraging flocks. As an extreme, and increasingly well- known example of endemic “adaptive radiation”, the vangas have long been an evolutionary “flagship” for Madagascar, emblematic of the special nature of the Malagasy avifauna. Although after 20 years of study we are approaching an understanding of the evolutionary history of the Vangidae and of other endemic Madagas- can species, these birds themselves, excluding the Rufous Vangas, remain poorly known in life. For most of these species, even the most basic aspects of their natural history, such as their habitat requirements, their diets and foraging strategies, their territory sizes, nesting biology and social behavior, remain almost unknown. So many questions remain to be answered. I hope that this special feature concerning what is and, perhaps more importantly, what is not known about the birds of Madagascar, will spur further interest in studying (and conserving) them among a new generation of ornithologists and a new generation of the Malagasy people.

Corresponding Editor Masahiko Nakamura Laboratory of Animal Ecology, Department of Biology, Joetsu University of Education, 1 Yamayashiki-machi, Joetsu-shi, Niigata 943–8512, Japan

2 Yamagishi S (2005) Social organization of the Rufous REFERENCES Vanga: the ecology of Vangas—Birds endemic to Eguchi K, Yamagishi S, Asai S, Nagata H & Hino T Madagascar. Kyoto University Press, Kyoto. (2002) Helping does not enhance reproductive suc- Yamagishi S & Eguchi K (1996) Comparative foraging cess of cooperatively breeding rufous vanga in Mada- ecology of madagascar vangids (Vangidae). Ibis 138: gascar. J Anim Ecol 71: 123–130. 283–290. Langrand O (1990) Guide to the birds of Madagascar. Yamagishi S, Honda M, Eguchi K & Thorstrom R pp 290–302. Yale Univ Press, New Haven and Lon- (2001) Extreme endemic radiation of the Malagasy don. vangas (Aves: Passeriformes). J Mol Evol 53: 39–46.

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