Simons Rachel D, Page Henry M, Zaleski Susan, Miller Robert, Dugan Jenifer E, Schroeder Donna M, Doheny Brandon
Earth Research Institute, University of California Santa Barbara, Santa Barbara, California, United States of America.
Marine Science Institute, University of California Santa Barbara, Santa Barbara, California, United States of America.
PLoS One. 2016 Mar 31;11(3):e0152261. doi: 10.1371/journal.pone.0152261. eCollection 2016.
Offshore structures provide habitat that could facilitate species range expansions and the introduction of non-native species into new geographic areas. Surveys of assemblages of seven offshore oil and gas platforms in the Santa Barbara Channel revealed a change in distribution of the non-native sessile invertebrate Watersipora subtorquata, a bryozoan with a planktonic larval duration (PLD) of 24 hours or less, from one platform in 2001 to four platforms in 2013. We use a three-dimensional biophysical model to assess whether larval dispersal via currents from harbors to platforms and among platforms is a plausible mechanism to explain the change in distribution of Watersipora and to predict potential spread to other platforms in the future. Hull fouling is another possible mechanism to explain the change in distribution of Watersipora. We find that larval dispersal via currents could account for the increase in distribution of Watersipora from one to four platforms and that Watersipora is unlikely to spread from these four platforms to additional platforms through larval dispersal. Our results also suggest that larvae with PLDs of 24 hours or less released from offshore platforms can attain much greater dispersal distances than larvae with PLDs of 24 hours or less released from nearshore habitat. We hypothesize that the enhanced dispersal distance of larvae released from offshore platforms is driven by a combination of the offshore hydrodynamic environment, larval behavior, and larval release above the seafloor.
近海结构提供了栖息地，可能会促进物种范围的扩大以及非本地物种进入新的地理区域。对圣巴巴拉海峡七个近海油气平台上生物群落的调查显示，非本地固着无脊椎动物亚扭瓦特斯苔藓虫（一种浮游幼虫期（PLD）为24小时或更短的苔藓虫）的分布发生了变化，从2001年的一个平台增加到2013年的四个平台。我们使用三维生物物理模型来评估幼虫通过水流从港口扩散到平台以及在平台之间扩散是否是解释瓦特斯苔藓虫分布变化并预测其未来向其他平台潜在扩散的合理机制。船体污损是解释瓦特斯苔藓虫分布变化的另一种可能机制。我们发现，通过水流的幼虫扩散可以解释瓦特斯苔藓虫从一个平台增加到四个平台的分布变化，并且瓦特斯苔藓虫不太可能通过幼虫扩散从这四个平台扩散到其他平台。我们的结果还表明，从近海平台释放的PLD为24小时或更短的幼虫比从近岸栖息地释放的PLD为24小时或更短的幼虫能够达到更大的扩散距离。我们推测，从近海平台释放的幼虫扩散距离增加是由近海流体动力环境、幼虫行为以及在海底上方的幼虫释放共同驱动的。
