Body condition indices of Asian green mussels, Perna viridis, from Indonesia

While part of a single country, the Indonesian archipelago covers several biogeographic regions, and the high levels of national shipping likely facilitate transfer of non-native organisms between the different regions. Two vessels of a domestic shipping line appear to have served as a transport vector for the Asian green mussel Perna viridis (Linnaeus, 1758) between regions. This species is indigenous in the western but not in the eastern part of the archipelago, separated historically by the Sunda Shelf. The green mussels collected from the hulls of the ferries when in eastern Indonesia showed a significantly lower body condition index than similar-sized individuals from three different western-Indonesian mussel populations. This was presumably due to reduced food supply during the ships' voyages. Although this transportinduced food shortage may initially limit the invasive potential (through reduced reproductive rates) of the translocated individuals, the risk that the species will extend its distributional range further into eastern Indonesia is high. If the species becomes widely established in eastern Indonesia, there will then be an increased risk of incursions to Australia, where the mussel is listed as a high-priority pest species.

印度尼西亚群岛虽同属一个国家管辖，却涵盖多个生物地理区系，而国内航运的高密度往来很可能促进了外来生物在不同区域间的传播。某国内航运公司的两艘船舶，似乎成为了翡翠贻贝（Perna viridis，Linnaeus, 1758）在各区域间传播的媒介。该物种原产于群岛西部海域，而东部海域并无其自然分布，这一分布格局历史上由巽他陆架（Sunda Shelf）所分隔。在印度尼西亚东部海域从渡轮船体采集到的翡翠贻贝，其身体状况指数显著低于印尼西部3个不同种群中体型相近的个体。这一现象推测是由于船舶航行期间食物供给不足所致。尽管这种由运输引发的食物短缺，初期可能会通过降低繁殖率来限制移殖个体的入侵潜力，但该物种进一步向印尼东部海域扩散的风险仍然很高。若该物种在印尼东部海域广泛定殖，那么其入侵澳大利亚的风险将进一步升高——目前澳大利亚已将该贻贝列为高优先级有害物种。