National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Santa Cruz, California, United States of America.
PLoS One. 2011;6(9):e25156. doi: 10.1371/journal.pone.0025156. Epub 2011 Sep 22.
The green sturgeon (Acipenser medirostris) is a highly migratory, oceanic, anadromous species with a complex life history that makes it vulnerable to species-wide threats in both freshwater and at sea. Green sturgeon population declines have preceded legal protection and curtailment of activities in marine environments deemed to increase its extinction risk. Yet, its marine habitat is poorly understood. We built a statistical model to characterize green sturgeon marine habitat using data from a coastal tracking array located along the Siletz Reef near Newport, Oregon, USA that recorded the passage of 37 acoustically tagged green sturgeon. We classified seafloor physical habitat features with high-resolution bathymetric and backscatter data. We then described the distribution of habitat components and their relationship to green sturgeon presence using ordination and subsequently used generalized linear model selection to identify important habitat components. Finally, we summarized depth and temperature recordings from seven green sturgeon present off the Oregon coast that were fitted with pop-off archival geolocation tags. Our analyses indicated that green sturgeon, on average, spent a longer duration in areas with high seafloor complexity, especially where a greater proportion of the substrate consists of boulders. Green sturgeon in marine habitats are primarily found at depths of 20-60 meters and from 9.5-16.0°C. Many sturgeon in this study were likely migrating in a northward direction, moving deeper, and may have been using complex seafloor habitat because it coincides with the distribution of benthic prey taxa or provides refuge from predators. Identifying important green sturgeon marine habitat is an essential step towards accurately defining the conditions that are necessary for its survival and will eventually yield range-wide, spatially explicit predictions of green sturgeon distribution.
美洲鲟（Acipenser medirostris）是一种高度洄游、海洋性、溯河产卵的物种，其复杂的生活史使其在淡水和海洋环境中都面临着广泛的物种威胁。在对海洋环境中的活动进行法律保护和限制之前，美洲鲟的数量已经减少，这些活动被认为增加了其灭绝风险。然而，其海洋生境却知之甚少。我们利用位于美国俄勒冈州纽波特附近锡勒特礁（Siletz Reef）的沿海跟踪阵列的数据，构建了一个统计模型来描述美洲鲟的海洋生境，该阵列记录了 37 条经声学标记的美洲鲟的通过情况。我们利用高分辨率水深和反向散射数据对海底物理生境特征进行分类。然后，我们使用排序描述了生境成分的分布及其与美洲鲟存在的关系，随后使用广义线性模型选择来确定重要的生境成分。最后，我们总结了在俄勒冈州海岸附近活动的 7 条带有弹出式档案地理定位标签的美洲鲟的水深和温度记录。我们的分析表明，美洲鲟平均在海底复杂性较高的区域停留的时间更长，尤其是在基质中较大比例由巨石组成的区域。海洋生境中的美洲鲟主要分布在水深 20-60 米和温度 9.5-16.0°C 的区域。本研究中的许多鲟鱼可能正在向北洄游，游得更深，并可能正在利用复杂的海底生境，因为这与底栖猎物类群的分布一致，或者为其提供了躲避捕食者的庇护所。确定重要的美洲鲟海洋生境是准确定义其生存所需条件的重要步骤，最终将生成广泛的、空间明确的美洲鲟分布预测。
