Jamaican Caving Notes
Wilson's Run Cave
May 10, 2005
Team: Stewart, Conolley, Slack
Notes: RS Stewart
Elizabeth Slack joined the team at this point of the expedition, having made the trip across from St Mary to Windsor with Ivor the night before. First thing in the morning, we'd loaded up the Rover and headed for Troy, which would be our base of operations for the next few days. Our intention was to stay with an associate of ours, Paul Bailey, who has a fine place near the end of the Troy to Tyre road (the last house before the Troy-Windsor trail). After making the drive around the east side of the Cockpit Country, via The Alps, Paul's was our first stop so that we could make arrangements for our stay. When we arrived, he was out on his farm somewhere, so we decided to hit our first target, Wilson's Run Cave, and then check back later when the rains would have driven him indoors.
The cave we sought had been explored once, by Liverpool in 1977. They had created an area map, in addition to a map of the cave, and by using this we were able to find the bottomland that contains the entrance, without a great deal of difficulty, although a lot of machete work was required and it was pouring rain the entire time.
The topology of the cockpit that we reached, where the cave is listed to be, is such: a medium-sized cockpit bottom is surrounded on most of it's circumference by slopes of up to 45 deg. Where the slope extends furthest, to a generally higher area to the south, much of the hill is in yam cultivation. Across the bottom of this cockpit, a stream flows. It rises from the bottom of the hill on the southeast and flows to the northwest, to sink, we believe, in Wilson's Run Cave. I say "believe", because although we did trace the course of this stream with much effort to where it sinks close to the other side of the cockpit, all we found there was a cut in a low hill where the waters sank into what appeared to be mud-choked boulders (the boulders were not visible, but something was holding a great amount of mud in place at the stream sink). This cut into the hill, at the sink, and faced in the right direction for the entrance according to the Liverpool cave map.
At any rate, there was no entrance to be entered, just small holes in a large section of inclined muddy pit into which the stream drained. It should be noted that in many cases the Jamaica Underground positions are out by hundreds of metres, so when there is a map available for a cave, such as Wilson's Run, this is how one makes a positive identification in districts where there are multiple caves. In this case, it was not possible. The area map, and the text description, certainly indicates that we had the right target, but we cannot put the identification at 100%. But, assuming that we indeed were at Wilson's Run Cave, the explanation for the lack of entry is obvious: the yams on the hills above.
Inquiries were made of residents of the area on how long the yam farming had been going on. We were informed that it began about 10 years ago (apx 1995), and greatly expanded in the last 2-3 years. A close look was taken at the cultivation technique, and it was seen that the main drainage trenches led directly downhill into the bottomland. The soil is deeply cultivated. A build-up of silt was seen in the streambed that crosses the cockpit bottom. Wilson's Run Cave, unfortunately, has likely joined Farmyard Cave, Rock Spring, on the list of caves lost due to agriculturally induced siltation. Perhaps if the drainage method employed on the hills above were to change, this stream cave might eventually be flushed clear, but this is uncertain.
It should be noted that the Liverpool Area Plan is somewhat deceiving. The track shown does not lead directly to the entrance, but rather to the top of a hill to the northwest (this is more obvious on the DEM with Arcview). The entrance is in the cockpit to the southeast, and we have added an edit to the Area Plan shown here to reflect this. This is the disc found above "Ent". That cockpit is the one that the stream crosses, and the yam farm is on the south and east hills.
A section of the DEM for the area can be found below (Fig. T-4). Darker is higher, and lighter is lower. The locations of the entrance (sink), and the stream rising have been noted. The track leads to the hill to the northwest of the cockpit.
It is problematic listing this cave in terms of vulnerability, because it is currently so degraded. If we had visited when the farm was first being cultivated, we would have listed it with a high vulnerability. In hopes that the land-use might change in the catchment for the cave, we will list it as high now.
We suggest that Wilson's Run Cave would be a good candidate for a project to examine soil conservation techniques, and the subsequent effect on cave siltation. If the input of topsoil were to be limited (while allowing the farm to continue activity), monitoring over a period of several years, or longer, would determine if a slower, more gentle rainy-season flow might eventually flush the silt through the system so that the cave again exists as a cave.
The drainage off the steep hills (30-40 deg slope) is the key in limiting the siltation. We have observed at other locations that drainage trenches that extend in contours across the hill, with end-drainage trenches only, limits soil loss. Perhaps the Jamaican government has research on-hand that suggests techniques. If a thorough search of the literature were done, and several methods that seem promising decided on, and these were applied to several sites, monitoring carried out over several years worth of rainy-seasons might soon determine the best approach for the Cockpit Country topography. The benefits would be two-fold: the farmers would keep more of their soil and fertilizer where it should be, and the hydrological connectivity of the karst would be maintained, or improved.
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