For alien invasive plant species dependent on frugivores for seed dispersal, traits that influence consumption can be important determinants of invasion and spread. However, trait comparisons between native and invasive species have documented mixed results. In Hawai‘i, one of the most invaded systems in the world, nearly all frugivory, and thus seed dispersal, is dependent on non-native birds. Moreover, the majority of dispersal events also involve invasive plants, suggesting the potential for an “invasional meltdown”. Here we compare fruit and seed traits between native and invasive plants and evaluate how those traits influence consumption by non-native avian frugivores. Although we found that most traits examined were similar between native and invasive fruiting species, invasive species tended to have higher fruit protein content, longer fruiting duration, were less likely to have orange fruits, and have less variable seed length. Longer fruiting duration and smaller seed size were important predictors for avian frugivore consumption. In combination, these results suggest that traits that increase probability of encounter (fruiting duration) and ability to be consumed (seed size) are more important for dispersal by frugivores than traits associated with fruit preferences and, thus, are driving the spread of invasive species and limiting dispersal of some native species. Further, we document an apparent seed size threshold for avian consumption (~ 7.0 mm), supporting previous work suggesting that large seeded species, particularly native plant species adapted for extinct large-bodied frugivores, are likely dispersal limited based on gape size limitation of the current non-native frugivore community.

对于依靠节食植物进行种子传播的外来入侵植物而言，影响食用的性状可能是入侵和传播的重要决定因素。但是，本地物种和入侵物种之间的性状比较已证明结果不一。在夏威夷，这是世界上入侵最严重的系统之一，几乎所有节食和种子传播都依赖于非本地鸟类。此外，大多数传播事件还涉及入侵植物，这表明“入侵融化”的可能性。在这里，我们比较了本地植物和入侵植物之间的果实和种子性状，并评估了这些性状如何影响非本地禽类食肉动物的食用。虽然我们发现所检查的大多数性状在本地和入侵结果种之间相似，但入侵种往往具有较高的水果蛋白含量，结果期更长，橙色果实的可能性较小，种子长度的可变性也较小。较长的结果期和较小的种子大小是食用鸟食动物的重要预测指标。综合起来，这些结果表明，增加相遇概率（结实持续时间）和食用能力（种子大小）的性状对于果肉的散布比与水果偏好相关的性状更重要，因此正在推动入侵物种的传播。并限制了一些本地物种的扩散。此外，我们记录了禽类食用的明显种子大小阈值（约7.0毫米），支持先前的工作表明，大型种子物种，特别是适应于已灭绝的大型节食动物的本土植物物种，