Population dynamics of meta-population and ineraction among local population

灭绝-（再）殖民化动力学的概念适用于自然或人为分散的种群。研究了生境大小和隔离度（与最近栖息地的距离）对各支流中斑状分布的河栖白蚁存在或不存在（发生）模式的影响。我们预测，发生的概率将随着栖息地大小的增加而增加，因为大型栖息地的灭绝率低；2)随着栖息地之间距离的增加而减少，因为在孤立的栖息地，再殖民化率低。我们的第一个预测得到了多莉瓦尔登发生对栖息地大小的逻辑回归的支持，表明小种群可能特别容易灭绝。相反，与最近种群的距离对多莉瓦尔登的发生没有影响。这表明，对无人栖息地的殖民是罕见的，与地理距离无关，灭绝率可能超过再殖民率。然而，先前的一项遗传研究揭示了距离隔离，这一模式与目前的结果不一致。这种差异可能是由于关于发生时间波动的现有资料有限造成的，值得进一步注意。

The concepts of extinction-(re) colonization dynamics applies to naturally or artificially fragmented populations. We investigated the effects of habitat size and isolation (distance to nearest occupied habitat) on the patterns of presence or absence (occurrence) of patchily distributed stream-dwelling Dolly Varden in individual tributaries. We predicted that the probability of occurrence would 1) increase with habitat size because of low extinction rates in large habitats and 2) decrease with increasing distance among habitats because of low recolonization rates in isolated habitats. Our first prediction was supported by a logistic regression of Dolly Varden occurrence on habitat size, indicating that small populations may be especially prone to extinction. Oppositely, distance to nearest population did not affect Dolly Varden occurrence. This suggests that colonization of unoccupied habitats was rare and independent of geographic distance, and that extinction rates may exceed recolonization rates. However, a previous genetic study revealed isolation by distance, a pattern inconsistent with the present results. This discrepancy may result from the limited available information on temporal fluctuations of occurrence and deserves further attention.