Fairbairn D J
Department of Biology, Concordia University, 1455 de Maisonneuve Blvd., H3G 1M8, Montreal, Quebec, Canada.
Oecologia. 1985 Apr;66(1):147-153. doi: 10.1007/BF00378567.
This paper reports the results of 2 experiments designed to determine if adult Gerris remigis (Hemiptera, heteroptera), a stream-dwelling waterstrider, tend to disperse preferentially upstream, as predicted by the colonization cycle hypothesis summarized by Muller (1982). Markrecapture observations and experimental removals were used to assess the distance and direction of movement of adult G. remigis along a small mountain stream, over a full year. These experiments indicated that adult G. remigis show a significant upstream bias in movement distance, but not in numbers of animals moving. This upstream bias is characteristic of pre-reproductive, sexually immature adults of both sexes, and occurs primarily in association with movements to and from diapause sites. Although the existence of a significant upstream bias in movement distances tends to support the colonization cycle hypothesis, the data from the removal experiments clearly show that upstream dispersal is not sufficient to compensate entirely for downstream drift.
本文报告了两项实验的结果，这两项实验旨在确定成年的美洲水黾（半翅目，异翅亚目），一种栖息在溪流中的黾蝽，是否如穆勒（1982年）总结的定殖循环假说所预测的那样，倾向于优先向上游扩散。标记重捕观察和实验性移除被用于评估成年美洲水黾在一整年的时间里沿着一条山间小溪移动的距离和方向。这些实验表明，成年美洲水黾在移动距离上表现出显著的向上游偏向，但在移动个体数量上没有。这种向上游偏向是两性生殖前、性未成熟成年个体的特征，并且主要与往返滞育地点的移动有关。尽管移动距离上存在显著的向上游偏向这一情况倾向于支持定殖循环假说，但移除实验的数据清楚地表明，向上游扩散不足以完全补偿下游漂流。
