Early warning and mitigation of the impact of invasive colonial ascidian tunicates

入侵物种是全球变化中最重要的人为因素之一。航运导致全球物种分布的同质化，导致本地物种生物多样性的灾难性减少，带来严重的经济后果。入侵物种导致加拿大东西海岸本地物种生物多样性大幅减少，并降低了水产养殖的可持续性。 我们在纽芬兰南部海岸的几个港口发现了两种入侵的殖民海鞘被囊动物。然而，它们尚未达到高密度，这为进行“入侵前”研究提供了难得的机会，并增加了成功缓解的可能性。我们的第一个目标是开发TaqMan基因探针和实时PCR检测，允许早期检测浮游生物样品中的单个海鞘卵或幼虫。这些探针将基于线粒体DNA的细胞色素氧化酶I基因的核苷酸序列，这是物种身份的可靠指标。基因探针可在3-5年内商业化。

Invasive species are among the most important anthropogenic components of global change. Shipping has led to a global homogenization of the distribution of species, resulting in catastrophic reduction in native species biodiversity with severe economic consequences. Invasive species have caused large reductions in native species biodiversity on the east and west coasts of Canada and have reduced the sustainability of aquaculture. We have discovered two species of invasive colonial ascidian tunicates in several harbours on the south coast of Newfoundland. They have not yet attained high densities however, providing the rare opportunity to conduct 'pre-invasion' research and increasing the probability of successful mitigation. Our first objective is to develop TaqMan gene probes and real-time PCR assays, permitting early detection of a single ascidian egg or larva in a plankton sample. These probes will be based upon the nucleotide sequence of the cytochrome oxidase I gene of mitochondrial DNA, a reliable indicator of species identity. The gene probes may be made commercially available in 3-5 years.