Ariopsis felis (Hardhead Catfish) is an abundant yet understudied estuarine fish species in the US Atlantic and Gulf of Mexico. Very little is known about the species’ trophic role and place in coastal food webs. This study was designed to provide baseline information on A. felis stable isotope values and to examine for any ontogenetic changes. n = 126 A. felis were sampled in the summer of 2018 in Terrebonne Bay, LA, USA, and muscle tissue was analyzed for stable carbon (δ¹³C) and nitrogen (δ¹⁵N) values. Overall, we found little evidence for any ontogenetic trophic niche shifts, expansions, or contractions; mature males and females have similar isotopic values and little to no differences were detected between immature and mature fish. Ultimately, A. felis occupy a trophic niche similar to that of other common estuarine fishes; however, the lack of any ontogenetic change in trophic position suggests that A. felis may be occupying a more stable and long-term place in coastal food webs.

Ariopsis felis（硬头Cat鱼）是美国大西洋和墨西哥湾地区一种数量丰富但未被充分研究的河口鱼类。对于该物种在沿海食物网中的营养作用和位置知之甚少。这项研究旨在提供有关粪猫链球菌稳定同位素值的基线信息，并检查任何个体发生的变化。Ñ = 126只A.蚤是在2018年在泰勒博恩湾，LA，USA夏天取样，并分析肌肉组织用于稳定碳（δ ¹³ C）和氮（δ ¹⁵N）个值。总体而言，我们发现几乎没有证据表明任何营养发生的生态位改变，扩展或收缩。成熟的雄性和雌性具有相似的同位素值，未成熟和成熟的鱼之间几乎没有差异。最终，A。felis占据了与其他河口鱼类相似的营养生态位。然而，营养位置上没有任何个体发生变化，这表明拟南芥可能在沿海食物网中占据了更稳定和长期的位置。