Low microplastic loads in riverine European eel (Anguilla anguilla) from southwest England during their marine-freshwater transition.

The microplastic loads in elvers of the critically endangered European eel Anguilla anguilla, sampled in the lower reaches of three English rivers, were very low (incidence: 3.3%, mean ± s.d.

Effects of preservation by ethanol on δ C and δ N of three tissues of the critically endangered European eel Anguilla anguilla.

The temporal effects of ethanol preservation on the δ C and δ N values of tissues excised from European eel Anguilla anguilla were assessed. Preservation significantly enriched C values of fin and mucus but not dorsal muscle. The C enrichment occurred in the initial 15 days of preservation and was independent of initial eel mass.

Non-lethal sampling for the stable isotope analysis of the critically endangered European eel Anguilla anguilla: how fin and mucus compare to dorsal muscle.

Ecological studies on the critically endangered European eel Anguilla anguilla often incorporate stable isotope analysis that typically uses dorsal muscle sampled from euthanised eels. To minimise the lethal sampling of imperilled populations, fin tissue and/or epidermal mucus can provide non-lethal alternatives to muscle. The results here indicate that δ C and δ N values of both eel fin and mucus are not significantly different from those of muscle and can be applied directly in comparative SI studies.