A survey of 2015 Alaska seaplane operations with predictions of transmission risk for aquatic invasive plants.

The main purpose of the survey was to establish the risk domain for introducing Elodea spp., an aquatic invasive species, by identifying unique seaplane destinations, flight origin, and annual flight frequency. We designed an electronic mapping tool programmed in JavaScript and using Mapbox Outdoors general-purpose maps (see Figure). The mapping tool enabled precise identification of flying destinations while avoiding spatial ambiguity. We first asked pilots to tell us their home base and then mark their 2015 first-leg freshwater destinations using the mapping tool. Once respondents placed the electronic marker, a pop-up menu asked the pilot to state the 2015 annual flights to the marked destination from their home base using the following intervals: less than 10, 10–25, 25–50, 50–75, 75–100, and more than 100 (Schwoerer et al., 2019). Our targeted population included pilots who flew seaplanes in Alaska in 2015, excluding Southeast Alaska. The sampling considered three pilot groups consisting of pilots who fly seaplanes for personal reasons, commercially, and for the government. We use a hierarchical Bayesian probability model to estimate transmission risk and associated uncertainty for each of 727 seaplane destinations that survey respondents identified.

本调查的核心目标为明确水生入侵物种伊乐藻属（Elodea spp.）的传入风险域，具体通过识别独特的水上飞机（seaplane）起降目的地、航班始发地及年度航班频次来实现。我们研发了一款基于JavaScript编程、依托Mapbox户外通用地图开发的电子绘图工具（详见附图）。该工具可精准锁定飞行目的地，有效规避空间歧义。调研流程首先邀请受访者告知其常驻基地，随后使用该工具标记其2015年首个航程的淡水起降目的地。当受访者完成电子标记点放置后，系统将弹出菜单，要求其说明2015年从其常驻基地飞往该标记目的地的年度航班频次，可选区间为：少于10次、10–25次、25–50次、50–75次、75–100次及100次以上（Schwoerer et al., 2019）。本次研究的目标群体为2015年在阿拉斯加州（不含阿拉斯加东南部地区）运营水上飞机的飞行员，抽样涵盖三类飞行员群体：因私人需求、商业用途及政府公务运营水上飞机的飞行员。我们采用分层贝叶斯概率模型，对受访者识别出的727个水上飞机起降目的地的传播风险及相关不确定性进行估算。