基于稳定同位素分析的野生黄条鰤食物组成研究

The feeding habits of wild yellowtail Seriola aureovittata based on stable isotopes analysis

通过检测工厂化养殖黄条鰤(Seriola aureovittata)各组织(肝脏、肠、心脏、鳃和肌肉)及饵料鱼的碳同位素比值(δ^(13)C),获得黄条鰤各组织的碳同位素判别值(Δ13C),结合大连海域野生黄条鰤及其潜在食物的δ^(13)C值,推测黄条鰤的食物来源。结果表明:工厂化养殖黄条鰤各组织Δ13C依次为肌肉(1.00‰)>鳃(0.98‰)>心脏(0.95‰)>肠(0.79‰)>肝脏(0.37‰)。大连海域野生黄条鰤的46种可能饵料生物的δ^(13)C为-21.61‰^-16.84‰。通过工厂化养殖黄条鰤肌肉组织的Δ13C,推测大连海域野生黄条鰤的食物组成以中上层鱼类为主,其次为中下层鱼类、底层鱼类、游泳虾形类、蟹类、头足类,其平均贡献率依次为64.0%、9.8%、9.0%、6.2%、5.1%、3.7%。

δ13C in liver, intestine, heart, gill and muscle from cultured yellowtail Seriola aureovittata and δ13C in prey organisms were measured,to produce the fractionation in each tissue. Meanwhile, the food sources for the wild yellowtails at Dalian Bay were estimated, in terms of fractionation and meas uring theδ13C in muscle of wild yellowtails and its potential foods. The results showed that the highest δ13C value in cultured yellowtails was in muscle （1.0‰）, followed by gill （0.98‰）, heart （0.95‰） , intestine （0.79‰） and liver （0.37‰）.δ13Cin samples of 46 kinds of potential prey organisms ranged from 21. 61‰- 16.84‰. Due to fractionation from cultured yellowtails in muscle（1. 0‰）, the contribution rate of prey organisms, from the biggest to the smallest, was as follows：pelagic fishes〉mesodemersal fishes〉demersal fishes〉crabs〉shrimps〉cephalopoda, with the average contribution rate of 64.0%、9.8%、9.0%、6.2%、5.1%and3.7%, respectively.