Environment Canada Saskatoon, Saskatchewan, Canada.
Department of Fisheries, Wildlife and Conservation Biology, University of Minnesota St. Paul., Minnesota.
Ecol Evol. 2014 Jan;4(2):132-43. doi: 10.1002/ece3.906. Epub 2013 Dec 18.
Estimates of range-wide abundance, harvest, and harvest rate are fundamental for sound inferences about the role of exploitation in the dynamics of free-ranging wildlife populations, but reliability of existing survey methods for abundance estimation is rarely assessed using alternative approaches. North American mallard populations have been surveyed each spring since 1955 using internationally coordinated aerial surveys, but population size can also be estimated with Lincoln's method using banding and harvest data. We estimated late summer population size of adult and juvenile male and female mallards in western, midcontinent, and eastern North America using Lincoln's method of dividing (i) total estimated harvest, [Formula: see text], by estimated harvest rate, [Formula: see text], calculated as (ii) direct band recovery rate, [Formula: see text], divided by the (iii) band reporting rate, [Formula: see text]. Our goal was to compare estimates based on Lincoln's method with traditional estimates based on aerial surveys. Lincoln estimates of adult males and females alive in the period June-September were 4.0 (range: 2.5-5.9), 1.8 (range: 0.6-3.0), and 1.8 (range: 1.3-2.7) times larger than respective aerial survey estimates for the western, midcontinent, and eastern mallard populations, and the two population estimates were only modestly correlated with each other (western: r = 0.70, 1993-2011; midcontinent: r = 0.54, 1961-2011; eastern: r = 0.50, 1993-2011). Higher Lincoln estimates are predictable given that the geographic scope of inference from Lincoln estimates is the entire population range, whereas sampling frames for aerial surveys are incomplete. Although each estimation method has a number of important potential biases, our review suggests that underestimation of total population size by aerial surveys is the most likely explanation. In addition to providing measures of total abundance, Lincoln's method provides estimates of fecundity and population sex ratio and could be used in integrated population models to provide greater insights about population dynamics and management of North American mallards and most other harvested species.
对广泛范围内的数量、收获和收获率进行估计，对于合理推断自由放养野生动物种群的开发利用在其动态中的作用至关重要，但很少使用替代方法来评估现有数量估计调查方法的可靠性。自 1955 年以来，每年春季都会使用国际协调的航空调查来调查北美的野鸭种群，但也可以使用林肯法，通过标记和收获数据来估计种群规模。我们使用林肯法来估计 1955 年以来，每年春季都会使用国际协调的航空调查来调查北美的野鸭种群，但也可以使用林肯法，通过标记和收获数据来估计种群规模。我们使用林肯法来估计 1955 年以来，每年春季都会使用国际协调的航空调查来调查北美的野鸭种群，但也可以使用林肯法，通过标记和收获数据来估计种群规模。我们使用林肯法来估计
成年雄性和雌性野鸭在夏季后期的数量，分别在北美西部、中大陆和东部地区，方法是将(i) 总估计收获量 [Formula: see text] 除以估计收获率 [Formula: see text]，其中估计收获率是(ii) 直接标记回收率 [Formula: see text] 除以(iii) 标记报告率 [Formula: see text]。
我们的目标是比较基于林肯法的估计值与基于航空调查的传统估计值。在 6 月至 9 月期间，成年雄性和雌性野鸭的林肯估计数分别为 4.0（范围：2.5-5.9）、1.8（范围：0.6-3.0）和 1.8（范围：1.3-2.7）倍，比各自的西部、中大陆和东部地区的航空调查估计值都要大，这两个种群估计值彼此之间的相关性也很适中（西部：r = 0.70，1993-2011；中大陆：r = 0.54，1961-2011；东部：r = 0.50，1993-2011）。
鉴于林肯估计的推理地理范围是整个种群范围，而航空调查的抽样框架并不完整，因此，林肯的更高估计值是可以预测的。
尽管每种估计方法都存在一些重要的潜在偏差，但我们的审查表明，航空调查对总种群规模的低估是最有可能的解释。
除了提供总数量的衡量标准外，林肯法还提供了繁殖力和种群性别比的估计值，并可用于综合种群模型，以提供有关北美野鸭和大多数其他被猎物种的种群动态和管理的更深入见解。
