No abstract

No abstract

In this paper, we compile estimates of cod size distributions based on zooarchaeological data and contemporary length-frequency data to look at variability in size composition through time across the North Pacific, from the northern Kuril Islands through the Aleutian Islands to southeast Alaska. The results suggest that a strong longitudinal trend in cod size has remained consistent over time, with the largest cod found to the west. We find that five of nine sites show that overall cod length and distribution of the largest fish remain relatively unchanged. Two sites where we find truncation of the length distributions—or loss of the largest fish—are places where the modern fisheries have the longest history and have been most intense, suggesting a potential for anthropogenic impacts on these local populations. We acknowledge two limitations in these data: (1) there are differences in selectivity between the ancient and modern fisheries; and (2) seasonal variability in fish availability was observed to be an important explanatory variable in the modern data set, but the season of harvest is poorly understood for the ancient collections. Therefore, while differences observed between the two data sets suggest possible anthropogenic influence on the size structure of Pacific cod, they are not conclusive.

Fish bones at archaeological sites may be used to address anthropological questions about past fishing practices and trade, as well as biological questions about past species distributions. In both cases, it is important to distinguish fish caught locally from those transported longer distances to the disposal site. The necessary standard of proof may vary by the geographic scale of the study and proximity to fish habitat, but multiple lines of evidence should be brought to bear, such as regional ethnography or oral history, fishing artifacts, available local habitat, skeletal parts frequencies, and bone chemistry. An example from the American Pacific Northwest demonstrates the complexity of determining catch location. The question at the Grissom site was whether the bones could demonstrate past salmonid and other fish occurrence in the adjacent Caribou Creek. Of seven fish species identified, three species were interpreted as local catch, one as local but indicating a change in range, and three as equivocal.

No abstract