Jan 6, 2016

Lighthouse Cave

January 6, 2016

Today was super special for me. We trekked to Lighthouse Cave, located on the northeastern edge of the island. I was super excited to visit this site since my interests include the karst dissolution of caverns and sinkholes (blueholes) – which this island has many of. 

Dissolution feature on the island: Watling's Blue Hole

Another common dissolution feature on San Salvador Island; banana holes.

Ladder leading down to the Main Room
The cave was a short drive from base and is situated downhill from the 200 year-old lighthouse which is still in use. With us, were two machetes, in the event that we encountered heavy brush. At the end of this muddy path was what we came looking for: the cave entrance. The opening was a straight 15-foot drop. Luckily for us, there was ladder to make our way down the main entrance. The entrance is a collapse pit cave with a chamber that intersects the water table. Going down the stairs, the cavern smelled musty, its darkness broken up only by the light of our headlamps. The cavern floor was made of slippery limestone, which led to a submerged pathway further down. The tidal range is this cave is about 3 feet and we entered at low tide (10 a.m.), although we were surprised when we swam through areas where the water went up to our chin. Due to yesterday’s (January 5th) rain event, the water table was a little higher than we had expected. In a single file, we all swam with our headlamps through a maze of stalactites and curved walls in all sorts of variety that kept our heads looking in all directions.

A number of observations could be seen, the most prominent being the abundant speleothems. Stalactites, stalagmites, and curtains could be seen decorating the ceiling and walls. Bell holes are another karst feature of this cave that are known to house bats.
Panorama of the Main Room

The cave was rather small and ended at a small round chamber where we all gathered to take a group photo. On the way out of the cave, I hit my already injured knee on a limestone ledge that caused it to open up again. We followed the mud-lined path back to the parked truck and made our way to the top of the hill where the Dixon Hill lighthouse stands guard.

Dixon Hill Lighthouse

The group spiraled up the lighthouse where we were treated a 360 degree view of San Salvador. It was a beautiful panoramic display of tree cover, lakes, and teal blue waters.

Our exercise for the day was completing a dune profile of one of the beaches on the eastern coast. We were shocked at the amount of bottles, plastic, and parmesan cheese containers that was washed ashore. Curious to see its origin, I picked up a whipped cream can and saw it had made its way from Puerto Rico. I’m not sure if this was a result from Hurricane Joaquín or if this normally washes onto these beaches by currents.
Update: During October 2015's Hurricane Joaquin, a cargo ship crashed off shore, losing all of its cargo to the sea. Frontline flea & tick medication, parmesan cheese, and other products washed ashore and can still be seen to this day.   

Splendid views all around! Many thanks to Bruno who got a whole bunch of amazing shots with his GoPro!