Multiple mating and cooperative breeding in polygynandrous alpine accentors. II. Male mating tactics

Abundance and Breeding Ecology of Brown Accentors Prunella fulvescens in Lhasa, Tibet

“…Although Brown Accentors in my study area inhabited an alpine environment similar to those of Alpine Accentors in France and Japan (Nakamura 1998a(Nakamura , 1998b, and they also performed specialized foraging for small prey, a factor related with multiple mating (Davies & Lundberg 1984, Davies 1986, I still think that their mating system is social monogamy for the following reasons: 1) social units of the accentors encountered during the nesting period consisted of 1-2 individuals, and courtship displays involved only two pair members and occurred at a very low frequency. In contrast, in two multiple mating species, investigators (Nakamura 1990, 1998a, 1998b, Heer 1994, 1996 may regularly observe breeding social groups of 5-11 birds, multiple breeders that get involved in a courtship display and high rates of the display (e.g.…”

“…In contrast, in two multiple mating species, investigators (Nakamura 1990, 1998a, 1998b, Heer 1994, 1996 may regularly observe breeding social groups of 5-11 birds, multiple breeders that get involved in a courtship display and high rates of the display (e.g. in Alpine Accentor, average 0.5 per h, based on 2 358 records over four breeding seasons, Nakamura 1998a); 2) for Brown Accentors, I had no evidence of more than one male attending the young, which is unusual in species with multiple mating systems (Davies 1985, 1986, Nakamura 1998a); 3) variation in clutch size is great in Dunnock (3-7 eggs) in part as a result of females adjusting their clutch size according to the mating pattern, laying larger clutches if they can expect two males to feed the young (Davies & Hatchwell 1992).…”

“…This makes it difficult for a single male to monopolize females by territorial defence, but makes it possible for several males to associate with several females. Therefore only the polygynandrous mating system is formed in this species , Nakamura 1998a, 1998b.…”

“…In particular, the studies of these two species revealed an interesting, unusual mating system: cooperative polygynandry (e.g. Davies 1992, Nakamura 1998a, 1998b. In contrast, ecological information about those taxa occurring in the evolutionary centre of the species group is very limited (Ali & Ripley 1987, Chen & Luo 1998.…”

Note on the Morphology of the Sperm Storage Tubules in the Polygynandrous Alpine Accentor, Prunella collaris.

“…This species exhibits a high incidence of copulation in a polygynandrous mating system (Davies et al 1995, Nakamura 1990a, 1998b, which would bring about intense sperm competition. However, the overall light and electron microscopic features of the SSTs were headed Blackbird, Xanthocephalus xanthocephalus, (2,229±89; Briskie 1994).…”