Coral reproduction in Western Australia.
Coral reproduction in Western Australia.
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作者：
Gilmour J;Speed CW;Babcock R
幼虫的产生和补充是珊瑚种群维持的基础，但这些早期生命史阶段很容易受到物理条件极端变化的影响。环境管理者的目标是尽量减少珊瑚礁幼虫生产和补充的重要时期的人类影响，但这样做需要了解珊瑚繁殖的模式和时间。大多数珊瑚是雌雄同体或雌雄同体，具有孵化或广播产卵的繁殖方式。孵卵珊瑚是一些珊瑚礁的重要组成部分，会连续几个月产生幼虫。广播产卵珊瑚更为常见，并且在珊瑚礁之间的产卵模式表现出相当大的差异。澳大利亚周围的珊瑚礁，尤其是大堡礁，可能会发生高度同步的产卵。在澳大利亚偏远的西北海岸，对珊瑚繁殖的研究较少。最近向这些地区的工业扩张促进了研究，但相关数据通常包含在机密报告中。在这里，我们将灰色文献中的信息与公开的信息结合起来，以更新我们对西澳珊瑚繁殖的了解，涉及跨越 20° 纬度的十几个珊瑚礁中的数万种珊瑚和数百种物种。我们确定了珊瑚繁殖的广泛模式，但更详细的见解因抽样偏差而受到阻碍；大多数研究都集中在几个月内在几个珊瑚礁上采样的鹿角珊瑚物种上。在现有数据中，季节之间的产卵活动存在纬度梯度，所有珊瑚礁（除了温带西南部）都在秋季发生大规模产卵。春季期间，参与规模较小、多物种产卵的珊瑚数量从金伯利大洋礁石上的约四分之一减少到宁加洛的很少。在这些季节中，产卵集中在三月和/或四月，以及十月和/或十一月，具体取决于满月的时间。满月的时间决定了产卵是否分两个月进行，这在热带珊瑚礁上很常见。非鹿角珊瑚的可用数据很少，它们可能具有不同的繁殖模式。例如，大型滨珊瑚似乎在金伯利大洋珊瑚礁上从春季到秋季产卵，而在皮尔巴拉地区的夏季则产卵，那里的其他常见珊瑚（例如 Turbinaria 和 Pavona）也表现出与鹿角珊瑚不同的繁殖模式。金伯利大洋珊瑚礁上的孵卵珊瑚（Isopora 和 Seriatopora）似乎会在数月内形成浮球，可能在春季到秋季达到高峰；西澳其他珊瑚礁也可能出现类似的情况。知识差距也是由于难以识别物种和方法问题造成的。我们简要讨论了其中一些问题，并提出了一种量化全年生殖产出变化的方法。
Larval production and recruitment underpin the maintenance of coral populations, but these early life history stages are vulnerable to extreme variation in physical conditions. Environmental managers aim to minimise human impacts during significant periods of larval production and recruitment on reefs, but doing so requires knowledge of the modes and timing of coral reproduction. Most corals are hermaphroditic or gonochoric, with a brooding or broadcast spawning mode of reproduction. Brooding corals are a significant component of some reefs and produce larvae over consecutive months. Broadcast spawning corals are more common and display considerable variation in their patterns of spawning among reefs. Highly synchronous spawning can occur on reefs around Australia, particularly on the Great Barrier Reef. On Australia’s remote north-west coast there have been fewer studies of coral reproduction. The recent industrial expansion into these regions has facilitated research, but the associated data are often contained within confidential reports. Here we combine information in this grey-literature with that available publicly to update our knowledge of coral reproduction in WA, for tens of thousands of corals and hundreds of species from over a dozen reefs spanning 20° of latitude. We identified broad patterns in coral reproduction, but more detailed insights were hindered by biased sampling; most studies focused on species of Acropora sampled over a few months at several reefs. Within the existing data, there was a latitudinal gradient in spawning activity among seasons, with mass spawning during autumn occurring on all reefs (but the temperate south-west). Participation in a smaller, multi-specific spawning during spring decreased from approximately one quarter of corals on the Kimberley Oceanic reefs to little participation at Ningaloo. Within these seasons, spawning was concentrated in March and/or April, and October and/or November, depending on the timing of the full moon. The timing of the full moon determined whether spawning was split over two months, which was common on tropical reefs. There were few data available for non-Acropora corals, which may have different patterns of reproduction. For example, the massive Porites seemed to spawn through spring to autumn on Kimberley Oceanic reefs and during summer in the Pilbara region, where other common corals (e.g. Turbinaria & Pavona) also displayed different patterns of reproduction to the Acropora. The brooding corals (Isopora & Seriatopora) on Kimberley Oceanic reefs appeared to planulate during many months, possibly with peaks from spring to autumn; a similar pattern is likely on other WA reefs. Gaps in knowledge were also due to the difficulty in identifying species and issues with methodology. We briefly discuss some of these issues and suggest an approach to quantifying variation in reproductive output throughout a year.