Trapping activities in the Cayo Santiago rhesus monkey colony are normally limited to January and February of each year. The year 1984 was exceptional in that the trapping period was extended until early May. This paper examines the effects of the extended trapping period on mothers and infants who observed trapping activities but were not directly involved in them. Mother-infant pairs exposed to extended trapping activities spent significantly more time in contact and less time at a distance from each other than those not exposed, both during the time of exposure and for several weeks afterward. There were also consistent nonsignificant tendencies for exposed mothers to reject their infants less, to initiate a higher proportion of their contact and to play a larger role in maintaining proximity. This pattern of differences is consistent with the suggestion that mothers reacted to the extended trapping period by protecting their infants more and by encouraging independence less. The results demonstrate the sensitivity of mothers to human disturbance and illustrate the value of management policies like those on Cayo Santiago, that minimize human disturbance and restrict trapping to a consistent and limited period each year.