Collichthys lucidus is an important small economic fish,and in order to understand its nutritional structure and die-tary characteristics,we collected samples from the waters of the Pearl River Estuary in 2021 and 2022,and studied them from the perspectives of trophic niche,trophic structure index and feeding habit by on stable isotope technology.The results indicate that the δ13C and δ15N values of C.lucidus were(-18.74±1.41)‰ and(12.35±0.57)‰,respectively,with a trophic level of(3.25±0.17)‰.The δ13C value gradually increased when the body length was less than 100.00 mm,then decreased with the in-crease of body length.The δ15N value increased with the increase of body length when the body length was less than 110.00 mm,and the inflection point occurred at body length of 110.00-120.00 mm.The δ15N value was the lowest,and then increased with the increase of body length.When the body length was less than 100.00 mm and more than 120.00 mm,the trophic diversity was high,and the trophic niche width was large.When the body length was 100.00-120.00 mm,the redundancy and evenness were high,and the trophic niche distribution was uniform in the community,and the individuals with similar trophic cha-racteristics accounted for the majority.Bayesian mixing model tracing reveals that the highest food contribution proportion for C.lucidus was from zooplankton.The research provides a theoretical basis for the resource conservation and management of C.lucidus.
关键词
棘头梅童鱼/稳定同位素/生态位/营养级/珠江口
Key words
Collichthys lucidus/Stable isotope/Niche/Trophic level/Pearl River Estuary