Stable isotope analysis of a newly established macrofaunal food web 1.5Â years after the Hebei Spirit oil spill

- We examined trophic structure in a newly established community after an oil spill.
- This is the most extensive in situ isotopic analysis on an oiled benthic community.
- Consumer-food source δ13C and δ15N rejected influx of petroleum into the community.
- A novel circular statistics rejected trophic niche change of major feeding guilds.
- Prevalence of omnivory and trophic plasticity may promote the recovery process.

We examined trophic relationships in a newly established community 1.5 years after the Hebei Spirit oil spill on the west coast of Korea. Carbon and nitrogen stable isotope ratios in consumers and their potential food sources were compared between the oil-spill site and reference site, located 13.5 km from the oil-spill spot. The isotopic mixing model and a novel circular statistics rejected the influx of petrogenic carbon into the community and identified spatial consistencies such as the high contributions of microphytobenthos, food-chain length, and the isotopic niche of each feeding guild between sites. We suggested that high level of trophic plasticity and the prevalence of omnivory of consumers may promote the robustness of food web against the oil contamination. Furthermore, we highlighted the need of holistic approaches including different functional groups to quantify changes in the food web structure and assess the influence of different perturbations including oil spill.