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Report by Galen Hunter


The Southern Western Pond Turtle and Vernal Pools


[ Page updated - February 28, 2020 ]


In 1984, Dr. William J. Wallace wrote a brief paper ("Engva. The Place of the Salts.", unpublished) about his Spring 1961 excavation near the Salt Lake in Redondo Beach on "the northwest corner of the sandhill north of the Edison Steam plant". Before his concluding remarks, in the section of his paper he subtitled "Food Remains", is this text:

"Wholly unexpected was the finding of a good deal of Pond Turtle shell. Since they could not have survived in the ponds’ highly saline water, these creatures must have been taken in the vernal pools and according to Hugo Reid, sufferers from “decline” were fed their cooked meat."

This report simply and very briefly expands a bit on what Dr. Wallace wrote about the pond turtle and vernal pools of the area. For instance - was this shell Wallace excavated from a turtle that lived in the immediate area? There where two smaller pools of water existing into the historical period located immediately south of the Salt Lake. The most southernly pool was fresh water. Could this turtle have lived in that pool? Perhaps this turtle lived where presumably vernal pools existed along the hallow extending north of the Salt Lake for several miles. This hallow was part of the rain catchment area of the lake and there were low spots where water would have pooled up. So far, this writer has not found any historical documentation describing either vernal pools or Pond Turtles or their remains in this hallow. Perhaps the turtles were taken from vernal pools existing beyond the immediate area and brought to the Salt Lake site for consumption. In any case, both pond turtles and vernal pools no longer exist in the area. Why? The best answer this writer has found are the words Dr. Wallace used in his Engva paper to describe the site - "man-caused devastation". His full sentence in the paper being "Despite man-caused devastation and a veneer of modern rubbish, signs of former Indian presence could still be readily detected."

The condition of the site has only been more devastated in the last 60 years. So, the best this writer can do right now is research the situation and present results. For instance, the scientific name for the species of pond turtle Dr. Wallace excavated portions of shells of is almost certainly "Actinemys pallida". This is the scientific name of the only native turtle to western Southern California and Mexico. Other common names for this turtle include Southern Western Pond Turtle and Southwestern Pond Turtle. It is a species of small to medium-sized in the family Emydidae. Scientific names evolve over time - the recent previous scientific name for this turtle was "Actinemys marmorata" also known commonly as the Western pond Turtle and the Pacific pond turtle. The former name(s) remain the name for the species of native turtle of northern California to Canada.



[Figure 1 - Photograph of the Western Pond Turtle (or the Southern Western Pond Turtle).]



[Figure 2 - Portion of the 1854 map by George Hansen of the land he surveyed for the Pacific Salt Works Company, the second registered corporation in Los Angeles County.]


Portion of deposition of James H. Lauder, December 15, 1856, in U.S. Land Claims Court in the dispute over who owned the Salt Lake:

"... said ponds are three in number, lying in a straight line the most northerly one being much the largest the little on next south of that is smaller and shallower and nearly dry in the summer leaving only a small spot of quagmire as I have seen it. ... The middle pond is formed by overflowing of seepage from the largest and from waste water flowing from the works now carried on there - the smallest and most southernly pond is almost entirely fresh water and dries entirely early in the summer being supplied chiefly by the rain of winter and soaking from neighboring hills."


From a 2009 "International Symposium on Urban Wildlife and the Environment" is a conference presentation by Sara L. Schuster and Robert N. Fisher, United States Geological Survey, San Diego, CA. Their presentation is titled "Impacts of habitat loss, fragmentation, and the introduction of non-native species as a result of urbanization on the western pond turtle in southern California". The presentation description reads:

"More than 90% of southern California‟s riparian and aquatic habitats have been destroyed or modified by agriculture and urbanization. This has had profound effects on species dependant on these habitats including the western pond turtle (Actinemys marmorata), the only freshwater aquatic turtle native to southern California. We have been monitoring the southern California pond turtle populations since 2001 and have documented their decline. This decline has been a result of the direct and indirect effects of urbanization including habitat loss, habitat alteration, habitat fragmentation, the introduction of non-native species, and recreation activities. Our trapping efforts have detected a minimum of 15 species of non-native turtles in southern California with red-eared sliders and spiny softshell the most common. At sites occupied by non-native turtles, non-native turtles have outnumbered the native turtles. We have also documented a negative correlation between pond turtle presence and sites with recreational use, while non-native turtles are positively correlated with recreational use. Finally, pond turtle presence is positively correlated with the naturalness of a site while non-natives were more likely to occur at modified or artificial sites. Only a few viable pond turtle populations remain in southern California, most populations are male-biased with little to no recruitment. Currently, we are developing programs such as long-term monitoring, genetics microsatellite analysis, habitat suitability assessment, habitat restoration and creation, translocation, head starting, and captive breeding to be used as tools to promote the recovery of the pond turtles in southern California."