Natural Resource Damage Assessment and Restoration Program, U.S. Fish and Wildlife Service, 1011 E Tudor Rd, MS 361, Anchorage, AK, 99503, USA.
Division of Migratory Bird Management, U.S. Fish and Wildlife Service, Sacramento, CA, 95819, USA.
Environ Monit Assess. 2020 Mar 17;191(Suppl 4):815. doi: 10.1007/s10661-019-7920-3.
As part of the natural resource damage assessment for the Deepwater Horizon oil spill, a mathematical model was used to estimate the total number of bird carcasses deposited on shorelines based on the number of carcasses collected and adjustment factors such as detection probability and carcass persistence. Studies of carcass persistence occurred along sandy beaches and marsh edges in the northern Gulf of Mexico to obtain site-specific inputs for the model. We estimated persistence rates for these habitat types and evaluated the influence on persistence of carcass size, location of the carcass on the beach, dominant vegetation type in the marsh, carcass distance into marsh vegetation, and length of time a carcass was stranded on a shoreline. The length of time stranded had the greatest influence on persistence in both habitat types, with persistence initially relatively low and increasing logarithmically. Carcass size and position were weakly influential on sandy beaches. Carcass size had stronger influences along marsh edges, and marsh habitat type also affected persistence. We found evidence of a positive relationship between distance into the marsh and persistence during the first 24 h after carcass deployment.
作为墨西哥湾深海地平线溢油事故自然资源损害评估的一部分，利用数学模型根据采集的尸体数量以及检测概率和尸体持久性等调整因子来估算沉积在海岸线上的鸟类尸体总数。在墨西哥湾北部的沙质海滩和沼泽边缘进行了尸体持久性研究，为模型提供了特定地点的输入。我们估算了这些栖息地类型的持久性，并评估了尸体大小、尸体在海滩上的位置、沼泽中主要植被类型、尸体进入沼泽植被的距离以及尸体在岸边搁浅的时间对持久性的影响。在这两种栖息地类型中，搁浅时间对持久性的影响最大，随着时间的推移，持久性呈对数增长，最初相对较低。尸体大小和位置对沙质海滩的影响较弱。尸体大小在沼泽边缘的影响更大，而沼泽栖息地类型也影响持久性。我们发现，在尸体投放后 24 小时内，尸体进入沼泽的距离与持久性之间存在正相关关系。
