Small-scale differences in blue cod length distribution, growth, and trophic ecology in New Zealand

Growth and reproduction in marine fish populations can be strongly influenced by local habitat quality nutritional resources. Habitat degradation alter prey composition availability, and, consequently, trophic position dietary niche breadth of fish. In the present study, we compared length-frequency distributions, growth, stomach contents, isotopic values (δ 13 C δ 15 N) blue cod Parapercis colias subpopulations from biogenic reef habitats that were more shellfish dredges fine sediment New Zealand. Blue inhabiting degraded regions significantly smaller relied on different items than habitats. Results indicated areas occupying those relatively undisturbed reefs. Isotope mixing models demonstrated one predominantly suspended particulate organic matter, while other primarily macroalgae as their matter source. Dietary overlap was likely higher for habitats, with potential consequences growth reproduction. reefs showed a high degree individual specialisation. The study differences length distribution, ecology among coincided degradation. Ecosystem-based management solutions help regenerate high-quality reducing fisheries mortality within these critical