Inland Use of Marine Resources

Marine fauna constituted a distinctive and important set of resources for prehistoric San Diegans. Their archaeological residues are found primarily at processing and habitation sites located within 1-2 kilometers of the coast. However, smaller quantities of marine remains, particularly shell, occur at sites farther inland. Terry L. Jones (1992:2) suggested the use of 10 kilometers from the coast as the cutoff distance for distinguishing a “coastal foraging radius” from a zone of “terrestrial habitat away from the coast.”

The interpretation of marine residues at inland sites may shed light on prehistoric mobility patterns, exchange systems, and the uses to which marine resources were put. Several scenarios may be suggested to explain the occurrence of marine faunal remains at inland sites:

• The shell or bone may represent a food resource that was brought to an inland base by foraging parties that had made extended trips to the coast.
• The marine faunal remains may represent food resources acquired by residents of inland communities through exchange with their coast-based procurers.
• The remains may represent food resources that were carried inland at the time of a seasonal shift from a coastal to an inland settlement base. This was the interpretation offered by Leslie Quintero (1987) for marine fish bone recovered from the Deer Springs Site (SDM-W-223A). Quintero reported seasonality studies indicating that the fish found at the site had been procured during the warm months, probably late summer or early fall, whereas the occupation of the site had occurred primarily from fall through spring.
• The marine shell may represent debris from the manufacture of shell beads, ornaments, or shell tools. Arguing against this interpretation are the observations that the shell species most commonly represented among the inland residues were not typically used for beads or ornaments, and that shell tools seem to be rare at either coastal or inland sites in this region.
• Shell may have been utilized as a material in crushed form, perhaps for its color or its chemical properties. Shell was apparently used in other regions to neutralize the tannic acid of unleached acorns. If the material was used for such purposes in inland San Diego County, it is important to note that usable shell might have been collected from geologic sources and that interpretations based on radiocarbon dating of the shell or based on the marine habitats associated with the shellfish might be fallacious.
• Shells may have served as charms, children’s toys, or other items valued for their novelty rather than for any utilitarian function. The interpretive cautions noted above concerning geological sources for such shell would apply in this case as well. 

PROSPECTS

Future archaeological investigations may be able to clarify the ways in which inland communities made use of marine resources. Relevant aspects of the issue may include the chronology of such use, the specific invertebrate and vertebrate resources that were selected, their use for subsistence or other purposes, and the processing strategies that were employed.

Site	Distance from Coast (km)	Abundance of Fish Bone	Abundance of Shell	Shellfish Genera	References
SDI-149, etc.	11	—	trace	Astraea, Mytilus, Chione, 4 others	Carrico et al. 1991
SDI-186, etc.	18	trace	trace	Laevicardium, Chione, 7 others	Byrd et al. 1993
SDI-674	19	trace	trace	Donax, Chione, 4 others	Rosen 1984
SDI-731	37	—	trace	Argopecten, Tivela, 11 others	Waugh 1986
SDI-860	65	—	trace	Chione, Argopecten, Donax, Tivela, 2 others	True 1970
SDI-2537	92	—	trace	—	Wilke et al. 1986
SDI-4608	32	trace	—	—	Tuma 2004
SDI-4648, etc.	19	trace	trace	Trachycardium, 5 others	Cardenas and Van Wormer 1984
SDI-4763, etc.	18	—	trace	Haliotis, Chione	Rosen 1982
SDI-4807, etc.	21	—	moderate	Donax, Argopecten, Chione, 12 others	Cook 1978
SDI-5383	13	trace	trace	Chione, Argopecten, Polinices	Laylander 1989
SDI-5669	22	—	moderate	Chiton, Laevicardium, Tivela, 19 others	Berryman 1981
SDI-5680	28	trace	trace	11 genera	Dominici 1985
SDI-5935, etc.	18	trace	—	—	Kyle 1987
SDI-6153	32	trace	moderate	Mytilus, Chione, Argopecten, Astraea	Christenson 1981
SDI-9203, etc.	53	trace	trace	—	Phillips and Carrico 1986
SDI-9243, etc.	17	trace	trace	Chione, Argopecten, 7 others	Corum and White 1986; Corum 1986
SDI-9446, etc.	49	—	trace	—	Laylander and Christenson 1986
SDI-9476	19	trace	moderate	Mytilus, 10 others	Hector 1984
SDI-10,998, etc.	11	trace	moderate	Chione, Tivela, Argopecten, Mytilus, 14 others	Laylander 1992a
SDM-W-223A	20	moderate	moderate	Chione, Donax, Argopecten, 21 others	Quintero 1987
SDM-W-1556	14	trace	trace	Chione, Argopecten, 5 others	O’Neil 1982
Kitchen Creek	58	—	trace	Argopecten, Chione, 2 others	May 1975