Reproductive biology

Most Caprinae are polygamous, with dominant males enjoying priority access to females. Dominance is established through displays, threats, and direct combat, prior to or dur ing the rut. Fighting may involve locking horns and twisting, direct head-to-head clashes, or lateral or flank attacks. Head-on fighting may involve two animals running straight at each other before clashing horns, or rising up on their hind legs, then crashing down together. The sound may carry a long way through the mountains and all-out bouts between animals such as argali with their massive horns are an impressive spectacle. Thickened front parts of the skull protect them from damage. Rupicaprini do not use direct head butts but attack the flanks of rivals, attempting to stab with their short horns. Rut-related mortality is reported in musk ox and mountain goat. Male displays to females include tail raising, urine spraying, lip curls, low stretches, and kicks with the foreleg. Chamois males bob their head up and down in front of females and Himalayan tahr also nod and shake their heads in display. Mountain goat males mark vegetation during the rut with glands behind the horns, dig rutting pits, and paw the soil onto their flanks and undersides.

Caprinae living in northern latitudes and at high elevations show a strong seasonality in breeding. The particular period varies with locality and is timed so that births coincide with an abundance of fresh green growth in spring or early summer to meet the nutritional needs of lactation and growth of the young. Cold or wet weather at this time increases juve-

A Himalayan tahr (Hemitragus jemlahicus) on rocky ledge. (Photo by Tom McHugh/Photo Researchers, Inc. Reproduced by permission.)

nile mortality. Walia ibex and Barbary sheep may breed throughout the year, but still show seasonal peaks. Gestation period is around eight months in musk ox and five to seven months in other species. Single young are the norm, but twins are not uncommon in some species.

Pregnant females seek out secluded areas to have their young. Young Caprinae can stand soon after birth but normally hide for two to three days before following the female. Most species are weaned in four to five months.

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