El Niño and Trans-Holocene Trends in Eastern Pacific Fishes: Preliminary Data from Abrigo de los Escorpiones, Baja California

Author(s): Kathryn Mohlenhoff

Year: 2018

Summary

Many questions surround trends in prehistoric fisheries dynamics and fish use along the Pacific Coast of North America. Marine fish are particularly sensitive to changes in their environment, including variation in sea surface temperature that changes cyclically with the El Niño/Southern Oscillation. Trans-Holocene paleontological or archaeological sites with large faunal assemblages are the ideal tool for use in reconstructing these paleoenvironmental records. Here, I report preliminary data from Abrigo de los Escorpiones, a well-dated and stratified trans-Holocene site from the Pacific Coast of Baja California. A wide variety of fish taxa were identified, including a large proportion of surfperch (Embiotocidae). Rockfish (Sebastes sp.), sharks and rays (Elasmobranchii), and California sheephead (Semicossyphus pulcher), were also identified in this assemblage. Richness and evenness values were calculated as they have the potential to reflect El Niño frequency; higher values through time could indicate an expanding diet breath due to decreased encounter rates with the highest-ranked fishes. A significant increase in evenness values through time was revealed, which correlates with the increase in El Niño frequency in the late Holocene. This work has modern value; reconstructing an extended record of marine environmental change can inform on modern rehabilitation and conservation efforts.

Cite this Record

El Niño and Trans-Holocene Trends in Eastern Pacific Fishes: Preliminary Data from Abrigo de los Escorpiones, Baja California. Kathryn Mohlenhoff. Presented at The 82nd Annual Meeting of the Society for American Archaeology, Washington, DC. 2018 ( tDAR id: 443368)

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Spatial Coverage

min long: -124.189; min lat: 31.803 ; max long: -105.469; max lat: 43.58 ;

Record Identifiers

Abstract Id(s): 21473