1. In the past, sturgeons played an important role in commercial and recreational fisheries in the Danube River and its tributaries. Human impacts in the Danube River Basin coupled with exploitation of sturgeon stocks led to all species being either locally extinct, critically endangered or of unknown status.
2. Sterlet (Acipenser ruthenus, Linnaeus 1758) is the last known sturgeon species occurring in the upper and middle Danube; however, the population of this species is considered unbalanced and decreasing since the beginning of the twenty‐first century.
3. The decline of sturgeon stocks has been noted before owing to their economic importance. With commercial fisheries being forbidden in the Slovak section of the Danube River, there is generally no information available about the status of what is considered a local population.
4. Databases containing recreational catch of sterlet (2003–2018) and historical records of commercial harvest (1961–1990) were used to describe the trend in the weight and number of sterlet caught over the following years.
5. Modelling indicated that the number of fish caught each year appears to be lower, while the average weight of each individual is increasing. This might suggest that the population is ageing.
6. Although older individuals can contribute a great deal more to spawning because they produce a greater number of eggs, several problems are apparent. The number of spawners might be decreasing as a result of bycatch or fishing, their ability to spawn might be obstructed, or annual recruitment may fail owing to unpredictable events.
7. Although restocking programmes are in place to help maintain the sterlet population in the Danube River, their efficiency seems to be drastically low. In fact, restocking could be of little value unless studies on the availability of key habitats are conducted and their protection and restoration are ensured.

中文翻译：

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贝叶斯模型表明，多瑙河中游的虫种群（Acipenser ruthenus，Linnaeus 1758）正在老化

1. 过去，st鱼在多瑙河及其支流的商业和休闲渔业中发挥着重要作用。人类对多瑙河流域的影响，加上对st鱼资源的利用，导致所有物种在当地已灭绝，受到严重威胁或处于未知状态。
2. er鱼（Acipenser ruthenus，Linnaeus 1758）是多瑙河中上生的最后一种已知的species鱼。然而，自二十世纪初以来，该物种的种群被认为是不平衡的，并且正在减少。
3. 由于其economic鱼的经济重要性，been鱼的数量已经有所下降。由于多瑙河的斯洛伐克段禁止商业捕鱼，因此通常没有关于被认为是当地人口状况的信息。
4. 包含休闲捕捞的ster（2003-2018）和商业收获的历史记录（1961-1990）的数据库用于描述随后几年捕捞的的重量和数量的趋势。
5. 模型表明，每年捕获的鱼类数量似乎较少，而每个个体的平均体重却在增加。这可能表明人口正在老龄化。
6. 尽管较大的个体可以产生更多的卵，因此它们对产卵的贡献更大，但是仍然存在一些问题。由于兼捕或捕捞而产卵的数量可能正在减少，产卵的能力可能受到阻碍，或者由于不可预测的事件而导致年度招募失败。
7. 尽管实施了补养计划以帮助维持多瑙河的the虾种群，但其效率似乎极低。实际上，除非对关键栖息地的可利用性进行研究并确保对其进行保护和恢复，否则补给的价值很小。