A bioenergetic model for estimating the food requirements of Steller sea lions Eumetopias jubatus in Alaska, USA
A bioenergetic model for estimating the food requirements of Steller sea lions Eumetopias jubatus in Alaska, USA
复制标题
用于估算美国阿拉斯加北海狮 Eumetopias jubatus 食物需求的生物能量模型
DOI：
--
复制
发表时间：
2002
期刊：
影响因子：
--
通讯作者：
D. Rosen
中科院分区：
文献类型：
--
作者：
A. Winship;A. Trites;D. Rosen
应用广义生物能量学模型估算了美国阿拉斯加州海狮Eumetopias jubatus的食物需要量。投入包括按日期、人口规模和构成、饮食构成和能量含量划分的年龄和性别特定能量需求。利用参数值不确定度和蒙特卡罗模拟法计算模型预测误差。我们的模型表明，个体的能量需求一般在夏季繁殖季节(6月至8月)最低，而在冬季(12月至2月)和春季(3月至5月)最高，这主要是由于活动预算的变化。预测的相对日摄食量幼年动物最高(1岁雄性和雌性分别为体质量的12±3%和13±3%)，并随着年龄的增长而下降(14岁雄性和22岁雌性分别为体质量的5±1%和6±1%)。该模型预测的怀孕女性的平均每日食物需求量仅略高于相同年龄的非怀孕女性的预测平均每日食物需求量。然而，该模型表明，哺育幼崽的雌性比没有哺育幼崽的同龄雌性每天的平均食物需要量高约70%。在3组模型参数(饮食、人口和生物能量)中，饮食和生物能量参数的不确定性导致模型预测的最大差异。该模型提供了斯特勒海狮种群食物需求的定量估计，并为未来的研究提出了方向。
A generalized bioenergetic model was used to estimate the food requirements of Steller sea lions Eumetopias jubatus in Alaska, USA. Inputs included age- and sex-specific energy require- ments by date, population size and composition, and diet composition and energy content. Error in model predictions was calculated using uncertainty in parameter values and Monte Carlo simulation methods. Our model suggests that energy requirements of individuals were generally lowest in the summer breeding season (June to August) and highest in the winter (December to February) and spring (March to May) mainly due to changes in activity budgets. Predicted relative daily food requirements were highest for young animals (12 ± 3% SD and 13 ± 3% of body mass for 1 yr old males and females respectively) and decreased with age (5 ± 1% and 6 ± 1% of body mass for 14 yr old males and 22 yr old females respectively). The mean daily food requirement of pregnant females predicted by the model was only marginally greater than the predicted mean daily food requirement of non-pregnant females of the same age. However, the model suggested that the mean daily food requirement of females nursing pups was about 70% greater than females of the same age without pups. Of the 3 sets of model parameters (diet, population, and bioenergetic), uncertainty in diet and bioenergetic parameters resulted in the largest variation in model predictions. The model provides a quantitative estimate of the Steller sea lion population's food requirements and also suggests direc- tions for future research.