This study found a strong relationship between fin and muscle tissue in three Australian fish species, showing that non-lethally collected fin tissue can be used as a proxy for muscle tissue in isotopic trophic studies. We hypothesised that a strong linear relationship exists between fin and muscle δ¹³C and δ¹⁵N isotope ratios, and conversion equations can be developed where differences exist. We analysed fin and muscle tissues of three common species (Cyprinus carpio, Macquaria ambigua and Nematalosa erebi) from the Barwon–Darling River, New South Wales, Australia. There were significant differences between fin and muscle δ¹³C values for all species, and fin tissue was a good predictor of muscle tissue δ¹³C (r² = 0.77 for all species). The relationship between δ¹⁵N values was less consistent, with a significant difference found in one species, but fin tissue was still a good predictor (r² = 0.72 for all species). Developing species-specific tissue conversion models results in the least amount of error, but regional models result in similar error and are more accurate than general global models. These results are consistent with prior studies of different species. This study provides tissue conversion models for three species common to Australian lowland rivers, facilitating the inclusion of fish in food web studies with non-lethal collection methods.

这项研究发现了三种澳大利亚鱼类的鳍和肌肉组织之间有很强的关系，这表明在同位素营养研究中，非死皮收集的鳍组织可以用作肌肉组织的代理。我们假设翅片和肌肉之间存在δ很强的线性关系¹³ C和δ ^15个Ñ同位素比率，和变换式可以被开发，其中存在的差异。我们分析了来自澳大利亚新南威尔士州Barwon-Darling河的三种常见物种（鲤鱼，Macquaria ambigua和Nematalosa erebi）的鳍和肌肉组织。有鳍和肌肉之间δ差异显著¹³C值的所有物种，和鳍组织是肌肉组织的良好预测δ ¹³ C（- [R ²  = 0.77的所有物种）。δ之间的关系¹⁵的N值是不太一致，与一个物种显著差异发现，但翅片组织仍然是一个很好的预测（- [R ² =所有物种均为0.72）。发展特定物种的组织转化模型产生的误差最少，但是区域模型产生的误差相似，并且比一般的全局模型更准确。这些结果与不同物种的先前研究一致。这项研究为澳大利亚低地河流常见的三种物种提供了组织转化模型，以非致命性收集方法促进将鱼类纳入食物网研究。