Predicting and understanding the impact of biological invaders is a global ecological imperative. Progress has been made through the application of phenomenological analysis via comparative functional response analysis. However, little is known about the mechanisms which drive high-magnitude functional responses of invasive species, especially when compared to trophically analogous natives. Largemouth bass Micropterus salmoides is a freshwater invasive species evaluated as a more efficient predator, with a higher-magnitude functional response, compared to a native analogue, the Cape kurper Sandelia capensis. In order to determine what traits drive this difference we quantified handling time behaviours (detection time, catch time, processing time) of both predator species and prey/predator size ratio, and employ an ecomorphological approach to determine whether largemouth bass is a more specialised predator than Cape kurper. There was no difference in detection time between the species, but largemouth bass were significantly and on average five times faster at catching prey than Cape kurper. Both species’ processing time was positively related to prey size, but Cape kurper was on average 4.5 times faster than largemouth bass. Ecomorphological data indicate that largemouth bass was the more specialised pursuit hunter for fish, whereas Cape kurper was better at ambush hunting. This suggests that the ecological impact of largemouth bass may be exacerbated in areas where there is habitat simplification which can lead to the extirpation of local small-bodied fish. In addition, there may be non-consumptive detrimental effects on trophically analogous natives through competitive exclusion.

预测和了解生物入侵者的影响是全球生态迫切需要。通过比较功能响应分析的现象学分析的应用已经取得了进展。但是，对于驱动入侵物种高强度功能响应的机制知之甚少，特别是与营养类似的本地生物相比。大嘴鲈Micropterus salmoides是一种淡水入侵物种，与原生类似物Cape kurper Sandelia capensis相比，被评估为更有效的捕食者，具有更高幅度的功能反应。。为了确定是什么特征导致了这种差异，我们量化了捕食者物种和猎物/捕食者尺寸比的处理时间行为（检测时间，捕获时间，处理时间），并采用生态形态学方法确定大嘴鲈是否是更专业的捕食者比库珀海角。物种之间的检测时间没有差异，但是大嘴鲈在捕获猎物方面比开普·库珀（Cape kurper）快得多，平均要快五倍。两种物种的加工时间与猎物的大小呈正相关，但库珀角的平均速度是大嘴鲈的4.5倍。生态形态学数据表明，大嘴鲈是最专业的鱼类追猎者，而库珀海角在伏击中则更好。这表明，在栖息地得到简化的地区，大嘴鲈鱼的生态影响可能会加剧，这可能导致当地小体鱼的灭绝。此外，通过竞争排斥，对营养上类似的本地人可能会产生非消费性有害影响。