ABSTRACT New Zealand estuaries and harbours are subjected to increasing sediment deposition that can smother and bury infaunal communities, yet how coastal species respond to sediment deposition is not well understood. Here, we experimentally examined the effects of native marine sediment deposition on the NZ cockle (Austrovenus stutchburyi). Cockles were found to be highly mobile and capable burrowers, able to resurface within days from beneath 2–25 cm of sediment where no physical disturbance to their natural orientation occurred. Cockles were also resilient to daily (2 cm) reburials. However, following disturbance to their natural orientation, inverted cockles were significantly impeded when buried under 5–10 cm of sediment, with fewer adults resurfacing than sub-adults. Cockle populations are likely to be resilient to native sediment deposition, unless physically disturbed. When disturbed from their natural orientation in the sediment, higher mortality of larger adult-sized cockles would be predicted, with mortality increasing under thicker sediment deposits.

中文翻译：

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沉积物沉积对新西兰海扇 Austrovenus stutchburyi 的影响

摘要新西兰的河口和港口遭受越来越多的沉积物沉积，这会窒息和掩埋原生态群落，但沿海物种对沉积物沉积的反应尚不清楚。在这里，我们通过实验研究了原生海洋沉积物沉积对新西兰鸟蛤 (Austrovenus stutchburyi) 的影响。发现鸟蛤具有高度的移动性和能力，能够在几天内从 2 至 25 厘米的沉积物下方重新浮出水面，而不会对其自然方向产生物理干扰。鸟蛤也能适应每天（2 厘米）的重新埋葬。然而，由于自然方向受到干扰，倒鸟蛤在埋在 5-10 厘米的沉积物下时受到显着阻碍，成鱼重新浮出水面的数量少于亚成鱼。除非受到物理干扰，鸟蛤种群可能对原生沉积物沉积具有弹性。当它们在沉积物中的自然方向受到干扰时，预计较大的成年鸟蛤的死亡率会更高，而在较厚的沉积物沉积下死亡率会增加。