Quantitative eDNA estimates show a strong correlation with Northern Pike biomass in a controlled environment

Northern pike, Esox Lucius , is one of the most important species for recreational fisheries in Sweden and as a top-predator; it holds an role food web. Despite its ecological socioeconomic significance, pike largely neglected current monitoring programs because seldom caught by conventional methods. As result, there not sufficient data management authorities to employ biologically justified strategies. To be able further understand ecology monitor populations, new methods are needed. Recent developments environmental DNA (eDNA) has shown potential produce (semi-)quantitative estimates fish biomass. However, amount eDNA water may vary depending on temperature, size, age density, therefore first evaluate effect biotic abiotic factors biomass relationships. Here, we evaluated relationship between concentration individual keeping adult varying size (0.75 – 3.41 kg, n = 11) individually outdoor mesocosms (~7000 L) filled with from adjacent Lake Mälaren. Samples were collected filtering through combination cellulose nitrate glass microfiber filter membranes. After comparison different extraction methods, was extracted using Chelex 100 resin, low-cost fast method. subsequently diluted 1:8 alleviate problems inhibition. A TaqMan assay targeting Cytochrome Oxidase I developed Olsen et al.(Olsen al., 2016, 2015) used quantify eDNA. The results show strong positive indicating that latter represents promising tool estimating natural waters. References: Olsen, J.B., Lewis, C.J., Massengill, R.L., Dunker, K.J., Wenburg, J.K., 2016. Erratum to: An evaluation target specificity sensitivity three qPCR detecting Pike (Esox lucius). Conservation Genetics Resources 8. 2015. assays 7.