Sound fisheries management requires knowledge of how the reproductive biology of targeted species varies over space and time and responds to external drivers. We determined the size at maturity and fecundity of the blue swimmer crab Portunus armatus (A. Milne-Edwards, 1861) (Brachyura: Portunidae) along the west coast of Australia at monthly, annual and interdecadal (1990s versus 2010s) time scales. The size at maturity of females determined by abdominal morphology (carapace width (CW) at 50% maturity (CW50)) was highest in sub-tropical Shark Bay at 26°S (104 mm), and declined latitudinally to temperate Geographe Bay at 34°S (93 mm). A notable exception was in a marine embayment at 32°S (Cockburn Sound), where CW50 was significantly lower than all other locations (83 mm). In contrast, batch fecundity was lower in sub-tropical (830,000 eggs at 127 mm CW) than temperate waters (950,000–990,000 eggs). Temporally, CW50 was significantly higher during January-June (typical growth period, encompassing the warmest months of the year) than during July-December (breeding period), and also differed between months, years, and decades. Positive correlations between water temperature, monthly and annual estimates of CW50, and functional maturity (size at first ovigery), were detected in most locations. Annual CW50 also increased with population density, particularly in locations where abundances and biomass were lowest. Results highlight plasticity in the reproductive biology of this portunid in response to environmental drivers such as temperature. Regular review of such parameters is important for ensuring robust fisheries management and stock assessments.

中文翻译：

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温度驱动蓝色游泳蟹 Portunus armatus A. Milne-Edwards 生殖生物学的时空变化，1861 年（十足目：短尾：梭子蟹科）

健全的渔业管理需要了解目标物种的生殖生物学如何随空间和时间变化以及如何响应外部驱动因素。我们确定了澳大利亚西海岸的蓝游泳蟹 Portunus armatus (A. Milne-Edwards, 1861) (Brachyura: Portunidae) 在月度、年度和年代际 (1990 年代与 2010 年代) 时间尺度上的大小和繁殖力。由腹部形态决定的雌性成熟时的大小（50%成熟时的甲壳宽度（CW）（CW50））在亚热带鲨鱼湾在 26°S（104 毫米）最高，纬度下降至温带地理湾在 34 °S（93 毫米）。一个明显的例外是在南纬 32°（科本湾）的一个海港，其中 CW50 明显低于所有其他位置（83 毫米）。相比之下，亚热带地区的批次繁殖力较低（830，000 个鸡蛋在 127 毫米 CW）比温带水域（950,000–990,000 个鸡蛋）。从时间上看，CW50 在 1 月至 6 月（典型的生长期，包括一年中最温暖的月份）显着高于 7 月至 12 月（繁殖期），并且在月份、年份和几十年之间也存在差异。在大多数地方都检测到水温、CW50 的月度和年度估计值以及功能成熟度（第一次产卵时的大小）之间的正相关。年度 CW50 也随着人口密度的增加而增加，特别是在丰度和生物量最低的地方。结果突出了这种portunid的生殖生物学响应温度等环境驱动因素的可塑性。定期审查这些参数对于确保稳健的渔业管理和种群评估非常重要。