Conservation methods for Arctic fish and shrimp: Effects on color preservation, morphological changes, and museum applicability

Natural history collections function as long-term archives of biodiversity, where conservation methods have direct consequences for specimen morphology, color preservation, and long-term preservation. This is also relevant in Greenland, where plans for a conservation center and the establishment of local natural history collections create a need for knowledge about suitable conservation methods for Arctic species under both field and museum conditions.
This thesis investigated how five fluid preservation methods affected weight, length, and color in selected Arctic fish and shrimp. All methods resulted in measurable changes in both weight and length, with weight loss being most pronounced due to dehydration and tissue alteration. Color preservation depends on both the method and the type of pigment. Formaldehyde and ethanol fixation followed by immersion in ethanol preserved carotenoids and structural colors in the short term, but with a gradual fading over time, whereas prolonged storage in formaldehyde was particularly destructive to these colors. Melanin by contrast, was generally better preserved by the aforementioned methods. Glycerin-based methods were insufficient, particularly without prior fixation. Freezing, which is often used temporarily in the field, caused structural damage after thawing.

No single method proved universally optimal, and the choice of conservation method should therefore depend on the intended future use of the specimens. The results contribute practical knowledge to museum practice and to the establishment of natural history collections in Greenland.