Data from: Keeping things local: subpopulation Nb and Ne in a stream network with partial barriers to fish migration

For organisms with overlapping generations that occur in metapopulations, uncertainty remains regarding the spatio-temporal scale of inference of estimates of the effective number of breeders (N^b)and whether these estimates can be used to predict generational Ne. We conducted a series of tests of the spatio-temporal scale of inference of estimates of Nb in nine consecutive cohorts within a long-term study of brook trout (Salvelinus fontinalis). We also tested a recently developed approach to estimate generational Ne from N^b and compared this to an alternative approach for estimating N^e that also accounts for age structure. Multiple lines of evidence were consistent with N^b corresponding to the local (subpopulation) spatial scale and the cohort-specific temporal scale. We found that at least four consecutive cohort-specific estimates of N^b were necessary to obtain reliable estimates of harmonic mean N^b for a subpopulation. Generational N^e derived from cohort-specific N^b were within 7 - 50% of an alternative approach to obtain, N^e suggesting some population-specificity for concordance between approaches. Our results regarding the spatio-temporal scale of inference for Nb should apply broadly to many taxa that exhibit overlapping generations and metapopulation structure and point to promising avenues for using cohort-specific N^b for local-scale genetic monitoring.对于存在重叠世代且处于集合种群（metapopulations）结构中的生物，有效繁殖个体数（effective number of breeders, N^b）估计值的推断时空尺度，以及此类估计值能否用于预测世代有效种群大小（generational N^e），仍存在不确定性。我们在针对溪红点鲑（Salvelinus fontinalis）的长期研究中，对9个连续同生群（cohorts）开展了一系列关于N^b推断时空尺度的检验。我们还测试了一种新近提出的、基于N^b估算世代有效种群大小（generational N^e）的方法，并将其与另一种同样考虑年龄结构的有效种群大小（effective population size, N^e）估算方法进行了对比。多项证据表明，N^b的估计值对应于局域（亚种群，subpopulation）空间尺度与同生群专属的时间尺度。我们发现，若要获取亚种群的可靠调和平均N^b估计值，至少需要4个连续的同生群专属N^b估计值。基于同生群专属N^b推导得到的世代N^e，与另一种方法得到的N^e差值在7%至50%之间，这表明两种方法的一致性存在种群特异性。我们关于N^b推断时空尺度的研究结果，可广泛推广至诸多存在重叠世代与集合种群结构的类群（taxa），同时也为利用同生群专属N^b开展局域尺度遗传监测指明了颇具前景的方向。