ABSTRACT

The invasive suspension-feeding Asian clam, Corbicula fluminea, is abundant and broadly distributed in temperate rivers and lakes, yet its feeding dynamics, including how feeding rate varies as a function of prey density (i.e., functional response) and temperature, are not well known. We therefore undertook feeding experiments using adult C. fluminea and varying concentrations of natural phytoplankton prey (measured as chlorophyll a concentration). Clearance (filtration) rates adjusted to clam wet weight (WW) did not vary with food concentration at either 15.0 or 20.5 °C and averaged 57.5 and 167.6 mL g⁻¹ WW h⁻¹, respectively. Ingestion rate, however, increased linearly with increasing food concentration at both 15.0 and 20.5 °C. Both clearance rate and ingestion rate showed strong temperature dependence, with Q₁₀ coefficient values of 6.99 and 5.65, respectively. These high feeding rates support the emerging view that this species is capable of extensive ecological impacts in both its native range and invaded habitats.

摘要

侵入性悬浮摄食亚洲蛤蜊Corbicula fluminea丰富且广泛分布在温带河流和湖泊中，但它​​的摄食动态，包括摄食率如何随猎物密度（即功能反应）和温度而变化，却不是很好已知。因此，我们使用成虫C.fluminea和不同浓度的天然浮游植物猎物（以叶绿素a浓度测量）进行了饲养实验。在 15.0 或 20.5 °C 时，根据蛤蜊湿重 (WW) 调整的清除（过滤）率不随食物浓度而变化，平均为 57.5 和 167.6 mL g ^-1 WW h ^-1， 分别。然而，摄食率在 15.0 和 20.5 °C 时随着食物浓度的增加而线性增加。清除率和摄取率都表现出强烈的温度依赖性，Q _{10 系}数值分别为 6.99 和 5.65。这些高摄食率支持了一种新观点，即该物种能够对其原生范围和入侵栖息地产生广泛的生态影响。