Estimating larval production of a broadcast spawner: the influence of density, aggregation, and the fertilization Allee effect.
Estimating larval production of a broadcast spawner: the influence of density, aggregation, and the fertilization Allee effect.
复制标题
估计广播产卵器的幼虫产量：密度、聚集和受精 Allee 效应的影响。
DOI：
10.1139/f10-125
复制
发表时间：
2011
影响因子：
2.4
通讯作者：
L. Botsford
中科院分区：
文献类型：
--
作者：
C. Lundquist;L. Botsford
捕鱼对繁殖的影响通常通过计算物种丰度和年龄结构变化对产卵量的影响来量化。对于广布产卵者，繁殖也取决于个体的局部空间分布。在低密度下，散放产卵器表现出Allee效应：由于产卵器之间的距离增加，卵的受精率下降。我们提出了一种基于配子扩散动力学和个体空间分布来评估渔业对广投产卵鱼可能影响的方法。我们使用一个基于个人的模型来模拟幼虫生产在一系列的不确定性的分散特性。以美国加州北方渔业中的红海胆为例，说明了我们的方法。红海胆的密度随空间（0.1-1.6 m-2）的变化而变化，聚集指数在低密度时最高。随着配子散布距离的增加，幼虫产量与密度呈线性关系。1996-1998年的平均幼鱼产量是渔业开始时产量的33.8%。在解释了平均密度的下降后，受精的Allee效应解释了幼鱼产量下降的21.7 ± 4.1%，而如果海胆没有聚集，则解释了45.2 ± 21.7%。
The effect of fishing on reproduction is typically quantified by computing the effects of changes in the species abundance and age structure on egg production. For broadcast spawners, reproduction also depends on the local spatial dis- tribution of individuals. Broadcast spawners exhibit an Allee effect at low density: a decline in the fertilization of eggs, owing to increased distance between spawners. We present a method for assessing the likely impact of a fishery on broad- cast spawners, based on gamete dispersion dynamics and individual spatial distributions. We use an individual-based model to simulate larval production over a range of uncertainties in dispersion characteristics. We illustrate our method for the red sea urchin, Strongylocentrotus franciscanus, fishery in northern California, USA. The density of red sea urchins varied over space (0.1-1.6� m -2 ), and indices of aggregation were highest at low densities. As gamete dispersion distances increased, larval production exhibited a more linear relationship with density. Average larval production in 1996-1998 was 33.8% of production near the inception of the fishery. After accounting for decreases in mean density, the fertilization Al- lee effect accounted for 21.7 ± 4.1% of the decrease in larval production, and 45.2 ± 21.7% if sea urchins were not aggre- gated.