PREDICTING SUITABLE MARINE HABITAT FOR PINK-FOOTED SHEARWATERS (ARDENNA CREATOPUS) IN THE WATERS ALONG THE PACIFIC COAST OF CANADA

This set of files contains the R code and input data used to run a Generalized Additive Model (GAM) for Pink-footed Shearwaters (PFSH) in Canadian Pacific waters. The model uses standardized at-sea survey data (1992–2019) to predict species presence and relative abundance in relation to key environmental covariates.The .R script includes data preparation, model fitting, validation, and prediction steps. The accompanying .csv file provides the standardized 2 km² observation dataset, and the shapefile defines the study area boundary used for mapping model outputs.Manuscript Abstract: Anthropogenic activities are threatening global marine ecosystems, with seabirds representing a vulnerable group that has experienced pronounced population declines in recent decades. The ability to identify important marine areas for vulnerable seabirds is fundamental to conservation initiatives. The Pink-footed Shearwater (Ardenna creatopus; listed as Endangered in Canada) breeds only in Chile, but during the non-breeding season it ranges northward to waters off Canada’s Pacific coast and the northern Gulf of Alaska. Utilizing at-sea survey data spanning from 1992 to 2019, we examined the relationship between the species’ distribution and environmental variables using a two-step Generalized Additive Model approach. Cross-validation with out-of-sample testing showed high predictive accuracy for occurrence (AUC = 0.94) and moderate performance for abundance predictions (Spearman’s rank correlation = 0.32, RMSE = 3.92, MAE = 0.45) at a 4 km² resolution. The results give us confidence in the model’s ability to identify areas suitable for Pink-footed Shearwaters. Distribution was strongly associated with several oceanographic and geographic factors, particularly latitude and distance to the continental shelfbreak. The findings of this study may help inform marine conservation efforts within Canada’s Pacific Exclusive Economic Zone and beyond.

本数据集包含用于在加拿大太平洋海域开展粉脚鹱（Pink-footed Shearwater, PFSH）广义相加模型（Generalized Additive Model, GAM）分析的R代码与输入数据。该模型利用标准化的海上调查数据（1992—2019年），基于关键环境协变量预测该物种的出现概率与相对丰度。配套的.R脚本涵盖数据预处理、模型拟合、验证与预测全流程。配套的.csv文件提供标准化的2平方千米观测数据集，而形状文件（shapefile）则划定了用于绘制模型输出结果的研究区域边界。
论文摘要：
人为活动正威胁着全球海洋生态系统，海鸟作为易受影响的类群，近几十年来种群数量出现了显著下降。为易危海鸟划定重要海洋栖息地，是保护工作的核心前提。粉脚鹱（Ardenna creatopus；在加拿大被列为濒危物种）仅在智利繁殖，非繁殖季会向北扩散至加拿大太平洋沿岸海域与阿拉斯加湾北部海域。本研究利用1992—2019年的海上调查数据，采用两步法广义相加模型分析该物种分布与环境变量之间的关联。通过留外样本测试的交叉验证结果显示，该模型在4平方千米分辨率下的物种出现预测精度较高（受试者工作特征曲线下面积AUC=0.94），丰度预测表现中等（斯皮尔曼秩相关系数=0.32，均方根误差RMSE=3.92，平均绝对误差MAE=0.45）。研究结果证实该模型可有效识别适宜粉脚鹱栖息的海域。该物种的分布与多项海洋学及地理学因素密切相关，尤以纬度与距大陆架坡折的距离最为显著。本研究结果可为加拿大太平洋专属经济区（Exclusive Economic Zone, EEZ）内外的海洋保护工作提供决策参考。