Dispersal and recruitment are fundamental processes for population recovery following disturbances in sessile species. While both processes are well understood for many terrestrial species, they still remain poorly resolved for some macroalgal species. Here we experimentally investigated the effective dispersal and recruit survival of a mesophotic Mediterranean fucoid, Cystoseira zosteroides. In three isolated populations, four sets of settlement collectors were placed at increasing distances (from 0 to 10 m) and different orientations (North, South, East and West). We observed that effective dispersal was restricted to populations’ vicinity, with an average of 6.43 m and not further than 13.33 m, following a Weibull distribution. During their first year of life, survival was up to 50%, but it was lower underneath the adult canopy, suggesting a negative density-dependence. To put our results in a broader context we compared the effective dispersal of other fucoid and kelp species reported in the literature, which confirmed the low dispersal ability of brown algae, in particular for fucoids, with an effective dispersal of few meters. Given the importance of recruitment for the persistence and recovery of populations after disturbances, these results underline the vulnerability of C. zosteroides and other fucoid species to escalating threats.

分散和募集是无柄物种受到干扰后恢复种群的基本过程。尽管对于许多陆生物种，这两种过程都广为人知，但对于某些大型藻类，它们的分辨力仍然很差。在这里，我们通过实验研究了一种有效的弥散性地中海藻类岩藻（Cystoseira zosteroides）的扩散和募集存活率。在三个孤立的种群中，四套定居点收集器以增加的距离（从0到10 m）和不同的方向（北，南，东和西）放置。我们观察到有效的扩散受到威布尔分布的限制，仅在人口附近，平均分布为6.43 m，且不超过13.33 m。在生命的第一年，存活率高达50％，但在成年树冠下却较低，这表明存在负密度依赖性。为了将我们的结果放在更广阔的背景下，我们比较了文献中报道的其他岩藻和海藻物种的有效扩散，这证实了褐藻的低扩散能力，特别是对于岩藻，具有几米的有效扩散能力。鉴于招募对于骚乱后居民的持久和恢复很重要，Ç。动物类固醇和其他岩藻糖类威胁不断升级。