Impact of Argentine ant on the native ant community in fynbos: spatial distribution and bait station dynamics.

This study examines the impact of the invasive Argentine ant on the spatial distribution of the native ant community in fynbos plots in Jonkershoek Nature Reserve, Western Cape Province, South Africa. Both the fine scale distribution and temporal bait colonisation patterns were examined. Two invaded and two uninvaded 50x50 m plots of 50 tuna-baited traps were used to sample the ant fauna (baits left out for between 5 min to 1 h). Results show that where the Argentine ant is present, species richness of native ants is significantly reduced. It also found that with the presence of this invader there are areas which are depleted of ants and two hypotheses are suggested to explain this. It also considers temporal dynamics at bait stations. Native ants shared a bait station with the Argentine ant on only two occasions, and in these cases there were very few Argentine ant individuals present. This study shows that the Argentine ant has a significant effect not only on native ant richness, but also on the distribution and abundance of individual ants at a fine scale.

本研究探讨了入侵物种阿根廷蚁（Argentine ant）对南非西开普省琼克斯霍克自然保护区内凡波斯（Fynbos）样地中本土蚁类群落空间分布的影响。研究同时考察了蚁类的细尺度分布格局与饵料定殖的时间动态模式。本研究选取2个已被阿根廷蚁入侵和2个未被入侵的50×50米样地，每个样地布设50个金枪鱼饵料诱捕器以采集蚁类类群（诱饵放置时长为5分钟至1小时）。结果显示，在阿根廷蚁定植的区域，本土蚁类的物种丰富度显著降低。研究同时发现，入侵蚁存在的区域会出现蚁类群落枯竭的现象，并据此提出了两种解释假说。本研究还分析了诱捕站的时间动态特征：本土蚁类仅在2次观测中与阿根廷蚁共享诱捕站，且此时诱捕站内的阿根廷蚁个体数量极少。本研究表明，阿根廷蚁不仅对本土蚁类的物种丰富度具有显著负面影响，还会在细尺度上改变单种蚁类的分布与种群丰度。