Tag Archives: eDNA

Hambrook J., Kimmel N., Robinson R., Foster D., Poesch M.S. and P. Hanington. (2025) Development, validation and implementation of eDNA-focused qPCR assays to detect and distinguish between Goldfish (Carassius auratus) and Prussian Carp (Carassius gibelio). Environmental DNA.

Abstract: 

The ability to accurately detect harmful aquatic invasive species in a species-specific manner is crucial to monitoring and management efforts. The Canadian province of Alberta currently harbors North America’s only invasive Prussian Carp populations, in addition to invasive Goldfish populations. The ability to quickly and accurately distinguish between these phenotypically similar fish, while also determining their presence in various waterbodies, is important in tracking invasions. In this work, we develop a cytochrome B–based assay, as well as an ND2-based assay to distinguish between these two fish. The 84-bp-long CytB assay featured a limit of detection of 5.8 and 4.8 copies/sample for Prussian Carp and Goldfish, respectively, while the 95-bp-long ND2 assay featured LODs of 6.3 and 1.6 copies/sample, respectively. We demonstrate that each of these assays fails to amplify these markers in closely related fish species common to Alberta. They also fail to amplify key invasive carp species, apart from the Goldfish ND2 assay, which cross-reacts with Common Carp. We then implement these assays and find 13 Goldfish and 47 Prussian Carp environmental DNA detection events throughout the Canadian province of Alberta. Finally, we show that assays broadly agree with visual observation data gathered from various reporting mechanisms, highlighting their validity in a monitoring program.

Citation: Hambrook J., Kimmel N., Robinson R., Foster D., Poesch M.S. and P. Hanington. (2025) Development, validation and implementation of eDNA-focused qPCR assays to detect and distinguish between Goldfish (Carassius auratus) and Prussian Carp (Carassius gibelio). Environmental DNA. 

Also Read:

Veilleux, H., McPherson, M.*, Cott, P., Poesch, M., S., Glover, C., and G. Goss. (2025) Environmental DNA as a tool to detect Arctic grayling and their habitat preferences in the Northwest Territories, Canada. Arctic Science 11: 1-12.

*Lab members: Mark Poesch. Check out opportunities in the lab!

Veilleux, H., McPherson, M.*, Cott, P., Poesch, M., S., Glover, C., and G. Goss. (2025) Environmental DNA as a tool to detect Arctic grayling and their habitat preferences in the Northwest Territories, Canada. Arctic Science 11: 1-12.

Abstract: 

Environmental DNA (eDNA) assays represent a non-invasive approach for biomonitoring. To assess Arctic grayling (Thymallus arcticus) populations in the Little Nahanni watershed of Northwest Territories (NWT), Canada, an eDNA assay that has been previously validated for use in fish of the Beringia lineage was used in conjunction with traditional survey methods (i.e., electrofishing). Forty-six 100-metre reaches of streams were assessed in August 2015. The assay successfully detected Arctic grayling of the Nahanni lineage, with an eDNA signal recorded at each of the 17 sites in which Arctic grayling were observed by traditional fish surveys, but also at 3 of the 29 sites where Arctic grayling were not observed. The presence of eDNA was related to habitat metrics via Random Forest and correlation analyses. Riffles and water temperature were identified as being predictive of Arctic grayling eDNA abundance; however, no significant relationship between eDNA abundance and biomass proxies (fish abundance and fork length metrics) could be established. The high congruence between traditional approaches and eDNA surveys suggests adoption of the latter method will enhance the temporal and spatial acuity of biomonitoring, thereby improving field assessment of Arctic grayling populations and contributing towards more effective conservation management of this species.

Citation: Veilleux, H., McPherson, M., Cott, P., Poesch, M., S., Glover, C., and G. Goss. (2025) Environmental DNA as a tool to detect Arctic grayling and their habitat preferences in the Northwest Territories, Canada. Arctic Science 11: 1-12.

Also Read:

McPherson, M.*, Lewis, J.B., Cott, P.B., Baker, L.F., Mochnacz, N.J. Swanson, H.K., and S. Poesch. (2023) Habitat use by fluvial Arctic Grayling (Thymallus arcticus) across life stages in northern mountain streams. Environmental Biology of Fishes 106: 1001-1020.

*Lab members: Morag McPherson and Mark Poesch. Check out opportunities in the lab!