The Occurrence of Fish Remains in Modern Lake Systems : A Test of the Stratified-Lake Mode

<p>Theories regarding the taphonomy of fishes in lacustrine environments have traditionally relied on an anoxic water column to explain the excellent preservation. This concept has never been directly tested in modern lacustrine environments that are thought to be analogous to the lacustrine environments predicted by the Stratified-lake Model. This research tested that model by searching for fish remains in 38 collected bottom samples of six modern lacustrine analogues, including Fayetteville Green Lake, New York. The bottom sediments of a warm, holomictic, shallow, and saline lake (Salton Sea, California) were also examined. Although laminated sediments were found in all of the lakes studied, only the Salton Sea sediments contained fish remains. This was surprising in that one would have expected the opposite: abundant fish remains in the stratified lakes and few, if any in the non-stratified, saline lake.</p> <p>In addition to the above described study, a preliminary study of the taphonomic processes effecting fish carcasses was carried out at Lake Perris, CA. Fresh fish carcasses were lowered in buckets to the bottom of the lake in both the epilimnion (water temperature >15 deg. c. and oxygenated) as well as the hypolimnion (water temperatureanoxic), directly testing the effects of oxygen content, temperature, and pressure on the preservation of fishes. In the warm, oxygenated water decomposition took place, producing enough gasses in the fish bodies to cause them to float to the surface. In the cool, anoxic environment, decomposition of the fleshy parts was initiated, but not enough gasses were produced to cause the fish to float to the surface. Further study is needed to better understand the separate effects of oxygen content, temperature, and pressure on the taphonomy of fishes.</p> <p>The results of this research strongly suggest that anoxia alone is not adequate to preserve fish remains and that some other physical, chemical, and/or biological condition may be necessary for the preservation of fishes. The results obtained at Salton Sea suggests that saline, alkaline lake waters may be important in the taphonomic process. Further studies in these environments should be productive.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Geology

Year

1988

Author dc:creator

• Britton, Douglas R.

Contributors dc:contributor

• H. Paul Buchheim
• Leonard Brand
• Lanny H. Fisk
• Earl Lathrop

• Aquaculture and Fisheries
• Biology
• Paleobiology
• Stratigraphy
• Paleoecology; Lake Ecology
• Loma Linda University. Geological Sciences program -- Dissertations

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/553

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-1547