Party composition in spider monkeys of tikal, Guatemala: A comparison of stationary vs. moving observers

Abstract

ABSTRACT. Three techniques of observing spider monkeys, Ateles geoffroyi, in the lowland rain forest of Guatemala at the archeological site of Tikal included shadowing animals, observations by a stationary observer above the canopy, and seven-observer "picket lines." Results indicate (1) total party size in shadow data is larger and probably more representative than that recorded by both stationary methods, (2) the relative proportions of monkeys in the five age/sex classes do not statistically differ among the three techniques, (3) picket line observations permit most accurate age/sex identification, and (4) the adult male: adult female ratio is 36:64.