This study has elucidated the environmental factors associated with spawning and the ecology of early life cycle stages of the sparid Acanthopagrus butcheri, which is atypically long-lived and large for a species confined to its natal estuary. The prevalence of A. butcheri eggs in monthly plankton samples from the Blackwood River Estuary, south-western Australia, in 2014/15, allied with long-term gonadal data, imply that spawning in this estuary commences in mid-spring (October) as water temperatures increase to ~17 °C and peak at ~22 °C in early summer (December). Eggs were initially found only in deeper, downstream areas, where a salt wedge had started to penetrate following precipitous seasonal decline in freshwater discharge. Spawning occurred progressively further upstream during November/December as the salt wedge continued its intrusion of the upper estuary. The concentrations of eggs and yolk-sac and preflexion larvae, which were related positively to salinity and temperature and less so to oxygen concentration, were located predominantly below the halocline, implying that successful spawning typically requires salinities ≥15. Concentrations of eggs and yolk-sac and preflexion larvae peaked in December and of flexion larvae in January. As the concentrations of copepod nauplii exceeded by orders of magnitude those of larval A. butcheri, with which they co-occur and constitute their main prey, it is unlikely that restricted food resources accounted for the poor recruitment of the 2014/15 year class. In this context, the presence of many yolk-sac larvae and preflexion larvae in the low oxygen concentrations, which have become increasingly prevalent in microtidal estuaries of south-western Australia due to climate change, is likely to have led to considerable mortality. In most populations throughout its range in southern Australia, A. butcheri spawns in a restricted period between the austral mid-spring and mid-summer, with the synchrony achieved through differences in the temperatures that cue spawning at different latitudes, i.e. higher temperature cues at lower and thus warmer latitudes. Spawning occurs earlier, however, in atypical estuaries in which salinities and temperatures are high in late winter/spring. Despite experiencing episodic recruitment, A. butcheri sustains substantial populations through maturing early relative to its maximum age, and therefore producing numerous offspring in those few years when spawning conditions are optimal. Episodic recruitment could thus be related to subtle inter-annual differences in environmental conditions during the short spawning periods, with oxygen levels greater than usual a potential key factor. The adaptability of A. butcheri makes this sparid useful in assessing the degree, direction and scale of climate change effects.

这项研究阐明了与刺A Achothopagrus butcheri的产卵和早期生命周期阶段的生态有关的环境因素，该物种非典型地长寿，并且对于局限于其出生河口的物种而言是大型的。屠杀曲霉的流行2014/15年，来自澳大利亚西南部布莱克伍德河河口的每月浮游生物样本中的卵与长期性腺数据相关联，这意味着该河口的产卵始于春季（十月），随着水温升高至约17 °C，在初夏（12月）达到〜22°C的峰值。鸡蛋最初仅在较深的下游地区发现，在淡水排放的季节性急剧下降之后，盐楔开始渗透。随着盐楔继续侵入上河口，在十一月/十二月的上游进一步发生了产卵。卵，卵黄囊和弯曲前幼虫的浓度主要与盐度和温度成正相关，而与氧浓度的相关性较小，与氧浓度成正比，暗示成功产卵通常需要盐度≥15。卵，卵黄囊和弯曲前幼虫的浓度在12月达到峰值，弯曲后幼虫的浓度在1月达到峰值。由于of足类无节幼体的浓度超过了幼虫的数量级它们共同存在并构成其主要猎物的A. butcheri，受限制的粮食资源不太可能构成2014/15年班级招募人数不多的原因。在这种情况下，由于气候变化，低氧浓度下存在许多卵黄囊幼虫和屈折前幼虫，由于气候变化，它们在澳大利亚西南部的微潮河口中变得越来越普遍，很可能导致相当大的死亡率。在澳大利亚南部，其分布范围内的大多数人口中，A。butcheri在南半球春季和仲夏之间的有限时间内产卵，通过在不同纬度产卵的温度差异实现同步，即在较低纬度和较高纬度产卵的温度较高。然而，在非典型河口产卵较早，在非典型河口，冬末/春季盐度和温度较高。尽管经历了突发募集，但A. butcheri通过相对于最大年龄的早熟来维持大量的种群，因此在产卵条件最佳的那几年中繁殖出许多后代。因此，突发性募集可能与短期产卵期间环境状况的细微年度间差异有关，其中氧气含量高于通常水平是潜在的关键因素。屠杀曲霉的适应性使其在评估气候变化影响的程度，方向和规模方面很有用。