Update 1

--> Camera Trapping At Stony Ford, CA.



From the 3ed of June to the the 31st of July, 2012 a camera trapping exercise was undertaken in Stonyford, California in order to assess the functionality of the camera traps BIOKPT 1 and BIOKPT 2 used in the camera trapping pilot study undertaken on the across the Laime Trail on the summit and talus slopes of Auyan Tepui, Venezuela. There was mention at the time that the traps periodically failed due to unknown causes; if the problems were battery issues, moisture problems, or some other mechanical problem is unknown. The Stonyford camera trapping test was undertaken to assess the camera traps in an environment which was resplendent with large game animals.



Survey area

The trapping occurred from 6/27/2012 to 7/31/12 in Stonyford, California in Calusa county, on the border of the Mendicino National Park. The site was selected due to the probability of minimal human interference with the cameras, though it is a settled rural area. Wildlife is abundant. Large mammals are mostly deer, elk, feral pigs, and rabbits. Trapping sites were selected due to this abundance of wildlife, and the cameras were placed along game trails and areas which acted as natural funnels for passing animals. In total, 520 pictures were taken from 6/27/2012 to 7/31/2012. Of these, approximately 243 photographs represent successful captures, in one night, of humans driving quad motorcycles within sufficient proximity to the cameras as to trigger their activation. Subsequent clouds of dust had a high reflective index, and continued to trigger the cameras after the vehicles had moved away. It is a testament to the Moultrie GameSpy that the trap BIOKPT 2 continued to function under these circumstances. The event is pictured below.

Thus, the total number of non-biased shots is approximately 289, as some shots from BIOKPT 2 during this period did detect wildlife (a lone turkey). Of the 289 wildlife shots, most were of deer, though a coyote was recorded, as we rabbits. Birds, insects, and small mammals also have the ability to trigger the camera traps, provided they got within a close enough range to the traps. Despite the known presence of pigs, none were recorded. This is due to many factors; the animosity between pigs and deer, camera placement, the wide range of feral pigs, and sampling bias in placing a camera trap facing an unbaited pig trap that had recently caught pigs. 

Elk and deer images taken below demonstrate that both nocturnal function and day time function are intact. Coyote video demonstrates that peripheral view functions with fast moving animals.

In terms of functionality, the cameras appear to be functioning properly, though BIOKPT 2 had a lower photographic rate, and appeared to be missing larger chunks of time. This problem was fixed when the camera was deactivated, relocated, and reactivated. There is are also a disproportionately large amount of empty video segments compared to photographs. This appears to be an artefact of fast moving animals moving out of range when the video function on BIOKPT 1 was enabled, based on the time signatures of photographs compared to video shots. Thermal events, such as heat rising from surface features, seems to trigger the cameras to some degree, although this will have to be tested.

Based on these tests, future camera trapping on the summits of the tepuis is feasible over an extended period of time. However, any future traps will need to be water proofed, and a solar charging panel will need to be integrated into every trap.

Current Research focus

The current research focus for this site is to develop carrying capacity models for the tepui summits. In doing so, it is possible to resolve the “anomalous fauna” problem which may represent sampling bias and research gaps in the study of tepui ecosystems. Part of the process of developing carrying capacity models is the production of meta-analysis of scholarly work on the tepui summits, which requires extensive literature reviews. As an example, when reviewing “The Mammals of Guiana” by G.H.H Tate, (1939), I was surprised to find that 31 mammals ranging from vesper mice to large carnivores were sighted during the 1937-38 Phelps expedition to Auyan Tepui. For the mammalian fauna recorded by Tate, I have been reviewing the taxonomic status of the species listed, checked against current literature and phylogenetic studies. This process has reduced the subspecies of Marmosa which are present in the Pantepui region (with defunct taxa being omitted), and has revealed a possible solution to the pelage coloration problem of tepui summit coatis with a review of Tates coati Nasua dichromatica, which is synonymous with Nasua nasua vittata. In order to construct carrying capacity models, it has become necessary to construct and compare lists of all known bryophytes, vascular plants, insect fauna, herpetofauna, avifauna, and mammals on the various tepui summits. In addition, spatial analysis and climate change models must be incorporated to determine potential limiting factors for tepui life. This task will be subdivided into a series of blog posts as the work become publishable.