Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland.
Biol Lett. 2024 Nov;20(11):20240319. doi: 10.1098/rsbl.2024.0319. Epub 2024 Nov 6.
Overfishing is one of the greatest threats to fish populations. Size-selective harvesting favours faster juvenile growth, younger maturation, small adult body size and low reproductive output. Such changes might be slow to recover and ultimately threaten population fitness and survival. To study the recovery potential of exploited experimental populations, we compared life-history traits in three differently size-selected experimental lines (large-selected, small-selected and random-selected) after five generations of harvesting and 10 subsequent generations of recovery (i.e. cessation of harvesting). We show that after a recovery period twice as long as the harvesting period, the differences in adult body size among the selection lines have eroded. While there was still a significant body size difference among the selection lines, this did not translate to differences in reproductive success. Although size-selective harvesting causes phenotypic changes in exploited fish populations, we show that such changes are reversible if the recovery period is long enough.
过度捕捞是鱼类种群面临的最大威胁之一。选择性捕捞有利于幼体更快生长、更早成熟、成体体型更小、繁殖产出更低。这些变化可能恢复缓慢,最终威胁到种群的适应能力和生存。为了研究受捕捞影响的实验种群的恢复潜力,我们比较了经过五代捕捞和十代恢复(即停止捕捞)后,三个不同体型选择实验种群的生活史特征。结果表明,在恢复时间是捕捞时间两倍的情况下,选择种群之间的成年体型差异已经消失。虽然选择种群之间仍然存在显著的体型差异,但这并没有转化为繁殖成功率的差异。虽然选择性捕捞会导致受捕捞鱼类种群的表型发生变化,但我们表明,如果恢复时间足够长,这些变化是可逆的。