干旱区生态环境知识资源中心

Suckling behavior adaptations are components of a reproductive strategy for successful breeding and offspring survival. In ungulates, maternal care of their young can be roughly classified into two dichotomous strategies: "hiding" and "following." Since goitered gazelles (Gazella subgutturosa) are a hiding species, we predicted that during the hiding period, suckling of young would be distributed unevenly throughout the day; then, when offspring were old enough to follow their mothers, suckling would be more evenly distributed. Over a 6-year period, we observed goitered gazelle in their natural environment and collected data on 3960 suckles and 397 suckling bouts. This data supported our hypothesis. In addition, goitered gazelles commonly birth twins of relatively small size, and since small-sized fawns are the most vulnerable to carnivores, they need intensive suckling for quicker growth during the hiding period. Therefore, we predicted that fawns, especially twins, would receive a larger supply of milk during their first several weeks, followed by a drastic decrease as they age. In spite of the high energy demands, this strategy along with birthing synchronization within the population is most likely an adaptation to both the pressure from predators and the desert environment which allows for only a very short period favorable for rearing young.