Bender Christopher J D, Moir Camden D, Hajibabaei Mehrdad, Boulding Elizabeth G
Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada.
Centre for Biodiversity Genomics, University of Guelph, Guelph, Ontario, Canada.
J Fish Biol. 2025 Jul;107(1):143-160. doi: 10.1111/jfb.70013. Epub 2025 Mar 4.
The stomach-less cunner wrasse (Tautogolabrus adspersus) has been experimentally used as a biological control agent for salmon lice that infest Atlantic salmon (Salmo salar) and to remove biofouling inside sea cages. The cunner demonstrates a strong population structure, suggesting that its diet, and therefore its usefulness for biological control, could differ among its populations along 1086 km of eastern Canada, in response to the biogeography of its prey species. Gastrointestinal tract samples were collected across 14 locations throughout five distinct regions from Southern Nova Scotia to Eastern Newfoundland between 2018 and 2022. Primary constituents of diet, identified using morphology and by percentage weight, were mussels, bryozoans, ascidians, gastropods, unidentified digested material and barnacles. Dietary DNA (dDNA) metabarcoding identified mussels in 46% of guts, amphipods in 45%, bryozoans in 31%, ascidians in 28% and sea anemones in 18%. Sea lice were rare yet present in samples from three separate regions. Permutational multivariate analysis of variance (PERMANOVA) based on DNA metabarcoding suggested that sampling region, location and year all significantly influence diet composition. Regional divergence in diet was greatest between Southwestern Nova Scotia and Northeastern Newfoundland. Invasive cionid ascidians were present almost exclusively in Nova Scotian samples, whereas brittle stars were present almost exclusively in Northeastern Newfoundland samples. dDNA metabarcoding enabled the detection of soft-bodied prey and often identified prey to the species level. Cunner were demersal feeders on neritic sessile or slow-moving benthic animals that comprise the biofouling community. In addition to preying on sea lice and invasive ascidians, we predict that cunner wrasses will reduce the density of biofouling communities on structures used in marine aquaculture.
无胃康氏锦鱼（Tautogolabrus adspersus）已被实验用作控制感染大西洋鲑（Salmo salar）的鲑鱼虱的生物防治剂，并用于清除海上网箱内的生物污垢。康氏锦鱼表现出很强的种群结构，这表明其饮食以及因此对生物防治的有用性，可能因其在加拿大东部1086公里沿线的种群而异，这取决于其猎物物种的生物地理学。2018年至2022年期间，在从新斯科舍省南部到纽芬兰东部的五个不同区域的14个地点采集了胃肠道样本。通过形态学和重量百分比确定的饮食主要成分是贻贝、苔藓虫、海鞘、腹足类动物、未识别的消化物质和藤壶。饮食DNA（dDNA）元条形码分析在46%的肠道中鉴定出贻贝，45%为双足类动物，31%为苔藓虫，28%为海鞘，18%为海葵。海虱很少见，但在来自三个不同区域的样本中存在。基于DNA元条形码分析的置换多变量方差分析（PERMANOVA）表明，采样区域、地点和年份均对饮食组成有显著影响。新斯科舍省西南部和纽芬兰东北部之间的饮食区域差异最大。入侵性的锡奥尼德海鞘几乎只出现在新斯科舍省的样本中，而蛇尾纲动物几乎只出现在纽芬兰东北部的样本中。dDNA元条形码分析能够检测到软体猎物，并常常能将猎物鉴定到物种水平。康氏锦鱼是浅海固着或行动缓慢的底栖动物的底栖摄食者，这些动物构成了生物污垢群落。除了捕食海虱和入侵性海鞘外，我们预测康氏锦鱼将降低海水养殖所用结构上生物污垢群落的密度。
