Sunday, April 29, 2007

Series of Posts for April 25 - April 29.

This starts a series of posts which gives some ideas of the Marine Biology class conducted in the Bahamas at the Gerace Research Center on San Salvador Island. This series lists in order from April 25 to April 29. Posts further down, are for earlier times in the course. For information on the Gerace Research Center, see the website: http://www.geraceresearchcenter.com/index.html )

Dixon Hill Lighthouse on San Salvador


Lighthouse on San Salvador, originally uploaded by powersdale.

This is a remaining lighthouse on San Salvador. This has provided navigation aid for ships for 120 years. For over 500 years, the reefs of the Bahamas have caused problems for sailors. Many ship wrecks have occurred. For over a hundred years, a major source of income for the inhabitants was salvaging cargo from ship wrecks. This was very important to the early economy. Keeping lighthouses in good repair was counter productive to the local economy.

A closeup of the kerosene light and lens

The light of lighthouse is shown here. It is burner for kerosene. This produces a strong light which is then directed in a beam by the lens that you see in the background.

The mechanism which turns the lens

This is the mechanism which turns the lens for the lighthouse. The next photo explains the energy source.

Weight system


Weight Mechanism, originally uploaded by powersdale.

This is equivalent to the weights which provide the energy for grandfather clocks. This weight is raised by a hand crank to near the top of the light house. The force of the weight causes the mechanism to turm rotates the lens of the lighthouse. Over a period of hours, the potential energy of the weight is used to turn the lens.

Entrance to Lighthouse Cave


Entrance to Lighthouse Cave, originally uploaded by powersdale.

The island of San Salvador (like all of the Bahamas) is made up of calcium carbonate from coral reefs. The calcium carbonate is slowly dissolved by rain water, resulting in many caves on the island.

Ladder needs replacement


Laddler needs replacement, originally uploaded by powersdale.

I believe we need to buy a ladder of the appropriate length, paint it purple, and send into to San Salvador for a replacement.

Some of the cave formations


Some of the cave formations, originally uploaded by powersdale.

More of the cave formations


More of the cav e formations, originally uploaded by powersdale.

Group making their way though the cave in fairly deep water.

Making ones way through a cave passage over half filled with water can be unnerving -- but what till you see creatures you might see in the cave.

Some warriors with guano war paint

Sirens in cave with glowing reds eyes.

You never know what you will find in a dark cave.

Student talk about politics in the Bahamas

The Bahaman political system was discussed in detail. They have a parliamentary form of government made up of 2 houses. Parliamentary elections are currently occurring in which all members are currently running for a 5 year term.

A rally of the FNM party


A rally of the FNM party, originally uploaded by powersdale.

This political rally by the FNM party was held about a half mile from the Gerace Research Center. It was attended by several of our students.

Jumping Off "The Thumb"


Jumping Off "The Thumb", originally uploaded by powersdale.

"The Thumb" is a projection of land into the Ocean. The ocean has undercut the calcium carbonate rock and this provides a "jumping-board" like projection about 15 feet above the water. Getting a good photo with a digital camera which has a slight delayed action takes some skill. Here are 3 fairly good pictures:

Different styles for different people

Two tumbling down


Two tumbling down, originally uploaded by powersdale.

Religion on San Salvador


DSCF0156, originally uploaded by powersdale.

A student talk which included a demonstration of a animated hymn sung at a church service.

A student presentation on Medicinal Plants


DSCF0150, originally uploaded by powersdale.

Dr. Bezotte giving a lecture on animal behavior.


DSCF0159, originally uploaded by powersdale.

Entrance to Owl's Hole


Entrance to Owl's Hole, originally uploaded by powersdale.

Owl's hole is a natural formation near the southern end of San Salvador Island. It was so named because an Owl used to inhabit it.

Here is how one descends into the hole.

Stalactites in Owl's Hole


Stalactites in Owl's Hole, originally uploaded by powersdale.

Although Owl's is primarily a 30 foot vertical shaft, it has the characteristics of a cave. It was probably formed by the dissolution of the calcium carbonate by water. Furthermore, stalactites have formed on the side wall.

Core Drill Samples


Core Drill Samples, originally uploaded by powersdale.

Core drill samples were taken and were used to determine the age of the rock formation as 300,000,000 years old.

Hermit Crab


Hermit Crab, originally uploaded by powersdale.

A hermit crab found significantly above the high tide line under a rock.

Hermit Crab up close


Hermit Crab up close, originally uploaded by powersdale.

Columbus Monument


Columbus Monument, originally uploaded by powersdale.

This is one of the places on the island that commemorates Columbus' first landing on the island. (They all couldn't have been first, but that is a detail.) The inscription is "This plaque was given by the government of Spain on the occasion of the visit of the replicas of the Christopher Columbus Caravels on February 10, 1992, in commemoration of the first landfall at San Salvador in 1492."

Fossilized Coral


Fossilized Coral, originally uploaded by powersdale.

The islands of the Bahamas were made by coral reefs. This particular fossilized coral is visiable in downtown Cockburn Town. It is estimated to be 250,000,000 years old.

Faculty Members (Powers, Bezotte, Lanterman) Sitting on Coral

After some discussion, we were able to persuade most of the students that the coral was older than the faculty.

SCUBA Team indicating they saw Hammerhead Sharks and another Shark

Stingray (Seen by SCUBA team)


Stingray, originally uploaded by powersdale.

Shark ! ! (End of April 25 - 29)


Shark, originally uploaded by powersdale.

This photo is more convincing than the prior photo taken 8 days earlier.

Tuesday, April 24, 2007

April 24

This was a fairly long day:
  • We retrieved traps we had placed the day before which trapped sediments in various locations which varied in the amount of sea grass present.
  • These samples were examined and then processed for quantification after drying.
  • Lisa gave a lecture on ocean sediments.
  • Students examined some of the samples under a microscope.
  • We traveled to the far end of the island to see bats in their natural enviroment.
  • We went to a beach to obtain shell samples for later identification.
  • We walked a half mile to a political rally that was to start at 7 pm. Because it hadn't started by 8:20, we left. It finally started at about 9 pm and is still going as it approaches midnight. (The music is nearly too loud even at a distance a half mile.)

An item I left off from last night. We were able to observe the craters on the first quarter moon last night. We also saw the rings of Saturn and probably its moon Titan. In general, the students are impressed with the astronomy part of the course.

I have been able to repair the telescope we are borrowing so that it is quite useable. More about this another night.

Below, see the pictures of today's activities.

Lisa helping students examine samples of sand that settled in traps in various ocean locations during the last 24 hours.


DSCF0004_edited, originally uploaded by powersdale.

Dr. Bezotte explaining the method sample processing.

DSCF0006, originally uploaded by powersdale.

Lisa giving a lecture on ocean sediments


DSCF0014_edited, originally uploaded by powersdale.

Students attending a lecture


DSCF0009_edited, originally uploaded by powersdale.

Students have been tolerating, enduring, and mostly enjoying several hours of lectures most days.

Students are examing some samples collected from the ocean.


DSCF0017_edited, originally uploaded by powersdale.

Digital Camera


Digital Camera, originally uploaded by powersdale.

I was able to bring a digital microscope camera which could hook to a laptop and display the little ocean critters we found. It also has the capabilities of capturing a still photo and video. You will next see some still photos. (I don't know how to upload video.)

A small trunk fish


A small trunk fish, originally uploaded by powersdale.

This young fish is only about 1 cm long.

An foraminifera in some small sand particles

http://www.ucmp.berkeley.edu/foram/forammm.html .

A small diatom with some fine sand particles

An unknown critter found in the sand collected in the ocean.

We will have the student identify this small creature.

From Mermaid Pond


From Mermaid Pond, originally uploaded by powersdale.

Here is something we were swimming with in Mermaid Pond. (Magnification of 600 x)

Crossing the road with care


Crossing the road with care, originally uploaded by powersdale.

In spite of the interstate sign, this road seldom has any traffic -- and at 80 degrees, we didn't see any snow removal equipment.

Entrance to Alter Cave


Entrance to Alter Cave, originally uploaded by powersdale.

This cave has some interesting bats in it. I wasn't able to photograph them with the lighting we had available. We didn't use a flash because that could make some of them fly. Their flying could result in some of the students screaming. Their screaming could result in more bats flying -- and thus escalating into complete mayhem. So I didn't a flash and didn't get a useful photo of the bats. I believe some of the others' cameras were able to get a good photo without a flash and I might upload one if I get one.

A couple of bats did fly, but no one screamed and everything went fairly smoothly.

There were some large roaches crawling on the walls

We didn't bother them and they didn't bother us.

Everyone appears to be happy to leave the cave (End April 24).

We went in search of the Dripping Rock Bat Cave (Start of April 23rd)

The roads are somewhat marked, but they appear on no publicly available maps. We were getting close when the next post down happened.

The Truck broke down


The Truck broke down, originally uploaded by powersdale.

The truck got stuck in reverse. Probably something wrong with the linkage. Some students walked about 1.5 miles to the beach. Two students and I hiked back up the road to get help and were offered took rides to a pub. There we were not able to make contact with the Research Center by either telephone or shortwave radio. Phone systems etc don't necessarily work well on the island. (The electricity was off on Sunday for 4 hours also.) Adam Breslin was able to get a ride back to the Center and help was sent in the form of a truck for the students plus a repairman for the broken down truck.

The two students and I were finally retrieved from the pub where we had played dominos. (We were practicing because the locals take this game very seriously.)

April 22 - Sunday

I don't have any photos from Sunday. Students caught up on their sleep, read books, played in the sun -- including volleyball. I took a total of 8 students to 2 different churchs. The locals are always interested in meeting our students.

Mermaid Team on Truck (Start of April 21 post)


Mermaid Team on Truck, originally uploaded by powersdale.

Here is the first "Mermaid Team". This is after a successful trip to Mermaid Pond, they are loaded on the truck and ready to return.

I show you this first so you know who were willing to go on this adventure -- and to assure you everyone was happy when we made it back. Read the posts further down to get more information.

Getting a sample of the layer of the flocculent

There is an organic flocculent layer at the bottom of the pond. Only scientists would be interested in wading in and getting some.