Energy Condition of Subsistence-harvested Fishes in Arctic Coastal Lagoons

An Iñupiat subsistence fisher catches whitefish at a channel trap dug into the beach gravel at the Tukrok River mouth near Anigaaq within Cape Krusenstern National Monument.

USFWS/Susan Georgette

Subsistence fishing is a culturally important practice for Indigenous residents of Northwest Alaska, and is important for maintaining food security for people of the region. Common species that are harvested include whitefishes (Coregoninae), flounders (Pleuronectidae), and cods (Gadidae). Coastal lagoons in the Western Arctic National Parklands of Alaska are important locations for subsistence fishing, because the channels and bodies of these features are reliable places to intercept coastal fishes, and are more sheltered from wind and storms compared to the open coastline. Subsistence harvesters prefer catching and eating certain fish species depending on personal preference, availability, and abundance. However, there is minimal information in the scientific literature about the energy content and nutritional value of the species of interest, particularly within lagoons. Assessment of the composition of fats, protein, and water amongst species is of interest to harvesters hoping to optimize their catch for winter sustenance, and is a useful metric for monitoring fish condition, population health, and changes to the environment. The potential effects of accelerating climate change and human development on the metabolic rates, diet, body condition, and energy density of fish is of great concern because these effects will, in turn, affect the people who depend on these species for food security.

Consequently, energy density and percentage of lipid, water, and protein content was characterized for 10 fish species in four coastal lagoons within Cape Krusenstern National Monument. We found that whitefishes, particularly Bering Cisco (Coregonus laurettae) and Least Cisco (Coregonus sardinella) exhibited the highest energy density, percentage of lipid, and percentage of protein content, significantly greater than that of marine cod and flounder species and published values from other regional species such as Pacific salmon (Oncorhynchus spp.) and lampfish (Myctophidae). Additionally, when the relative mean abundance and body weight of each species was taken into account, total energy value by availability in the lagoons was highest for whitefishes when compared with marine taxa. Given the impending effects of climate change and coastal construction in the region, it will be important to monitor the energy condition of lagoon fishes to ensure their quality and availability for subsistence harvesters.

Energy Condition of Subsistence-Harvested Fishes in Arctic Coastal Lagoons

Abstract

In Arctic Alaska, Indigenous and rural residents depend on wild-harvested foods for sustenance and the subsistence lifestyle is integral to their culture. Marine and diadromous fishes, which often occupy coastal lagoon habitats, are relied upon for subsistence harvest, particularly Pacific salmon, whitefishes (Coregoninae), cods (Gadidae), and flounder species (Pleuronectidae). However, little research has been conducted that assesses the energetic condition of these fishes, which are harvested by the tens of thousands annually. The effects of accelerating climate change and human development on the metabolic rates, diet, body condition, and energy density of fish is of great concern because these effects will, in turn, affect the people who depend on these species for food security. Consequently, we characterized energy density and percentage of lipid, water, and protein content of 10 fish species in four coastal lagoons within Cape Krusenstern National Monument, Alaska. We found that whitefishes, particularly Bering Cisco Coregonus laurettae and Least Cisco C. sardinella exhibited the highest energy density, percentage of lipid, and percentage of protein content, significantly greater than that of marine cod and flounder species, Fourhourn Sculpin Myoxocephalus quadricornis, freshwater Pond Smelt Hypomesus olidus, and values from other regional species that have been in published literature. Additionally, when the relative mean abundance and body weight of each species was taken into account, total energy value by availability in the lagoons was highest for whitefishes when compared with marine taxa and the freshwater Pond Smelt. Given the impending effects of climate change and coastal construction in the region, it will be important to monitor the energy condition of lagoon fishes to ensure their quality and availability for subsistence harvesters.

Fraley, K. M., M. D. Robards, J. Vollenweider, A. Whiting, T. Jones, M. C. Rogers. 2021. Energy Condition of Subsistence-Harvested Fishes in Arctic Coastal Lagoons. Marine and Coastal Fisheries: 13, p712–719.