Monday, June 18, 2007

Turtle Watch in Grenada; sailed to Isla Margarita

……..okay; now it’s later.  So, let’s talk about the Turtle Watch first so that things stay chronological.

The tour guide was Cuddy again.  He picked us up at 7:00 p.m. and then we made a swing by the Grenada Yacht Club to pick up a few more people.  Then it was a long ride up to the northeastern tip of Grenada on twisty little roads that made the trip seem even longer than it actually was in distance.  This is the largest beach in Grenada and where the turtles prefer to lay their eggs.  Funny thing, we know of 4 places in the Caribbean (Trinidad, Grenada, Bequia and Culebra) where turtles return year after year to lay their eggs; and all 4 of these beaches are on the northern sides of the respective islands.  We have no idea why they prefer the northern sides of these islands.  Just a turtle thing, I guess.

It was quite dark when we finally arrived at the northern beach about 9:30 p.m.  There was no ambient lighting anywhere nearby and no traces of any civilization, so the beach was quite dark on this moonless, cloudy night.  Luck was with us!  A turtle had recently ascended and had selected her spot where she was struggling to dig the deep hole where she would lay her eggs.  This was turtle number 712 to land on this beach so far this year.  Last year they only recorded about half that number for the entire year.  While we were on the beach, turtle number 713 arrived and ascended less than 100 feet away from turtle number 712.  One of the researchers later told me that numbers 714 and 715 also ascended while we were there, but they didn’t want to tell everyone because these 2 turtles were much farther down the beach and they didn’t want to deal with a large group of tourists tromping out there.  You are not allowed to use a regular flashlight but we had brought our red flashlight and that is allowed.  Since it was a dark, cloudy night and we had only a couple of red flashlights, it wasn’t possible to take proper photos.  Sorry.

So, “our” turtle was number 712.  And she was huge!  The researchers measured her first with lasers and then with old-fashioned measuring tapes.  Her shell was 169.3 cm long and 116.4 cm wide; that translates to almost 5 ft 7 in long and almost 4 ft wide.  We have never seen turtles this large in the wild but know others who have encountered them.  She was a leatherback and had been previously tagged, so they scanned her head tag and left rear flipper tag.  Her right rear flipper had been severely damaged by a shark and just a sliver of flipper remained, and she was struggling to dig the hole where she would lay her eggs.  The predominant predators of turtles are humans (fishing industry) and sharks. 

These turtles ascend from the sea and then walk up almost to the vegetation line.  They use their undersides and their flippers to select a spot in the sand that will provide the appropriate moisture content to incubate their eggs.  Then they start to dig --- and they dig and dig and dig and dig.  It can take them hours to dig a hole deep enough, which is about the depth of an adult man’s outstretched arm.  They stretch out their flippers to extend as far down as possible; and, as you can imagine, on a turtle this size the flippers are pretty darn big – probably 2 ft long and 18-inches wide.  The flipper is inserted down in the hole vertically; then she curls the flipper and scoops up the sand.  The sand-filled flipper is then brought up to ground level and she disperses it around the hole she is digging.  Her head and fore-flippers remain up out of the hole while the rear of her shell and her rear flippers descend somewhat.  The finished hole is deep but not wide and her rear flippers then rest on each side of the hole.  Now it is time to lay the eggs.

She positioned her rear end over the hole and started rhythmic breathing.  It was kind of cool to hear the turtle breathing like that.  She did not seem disturbed at all by all the people around her, although the researchers did have us all stand well away from her head.  One of the researchers donned latex gloves and lay down on the sand.  He extended his arm and caught all the turtle eggs in his hand.  He showed us several handfuls of eggs but his primary purpose was to count the eggs.  Turtle number 712 (she really should have been given a name!) produced a total of 97 fertilized or yolk eggs and 47 unfertilized eggs.  Obviously, only the fertilized eggs will hatch.  The unfertilized eggs are about 10% of the size of the fertilized eggs.  The purpose of the unfertilized eggs is to assist in maintaining proper moisture content inside the hole.  The eggs are not rigid like a bird’s egg; they are pliable and will absorb moisture from surrounding sand as needed for their incubation.  Still, only about 45% of the fertilized eggs will hatch.  Not a high survival rate!

The eggs and future hatchlings are now on their own.  The female turtle fills the hole with sand after laying her eggs.  She then spends about 20 to 30 minutes spreading the sand and camouflaging the area.  She then descends back into the sea and will not return to this beach to lay eggs again for the next 2 or 3 years.   The researchers have learned a lot by tagging these turtles but there is still a great deal they do not know.  They do know that the males never return to land; only the females return and that is only to lay their eggs.  They do not know if the turtles mate for life or simply mate once or if they mate repeatedly.  There is a lot more research to be done.  And this is obviously not a well-funded area of research. 

The figure for survival is astounding!  Many hatchlings die before they even enter the sea or shortly after they enter the sea.  The tiny turtles are preyed upon by many types of sea birds and they are also eaten by various fish and sharks.  Only one egg in a thousand produces a turtle that survives to adulthood.  With statistics like that it is a wonder that there are any sea turtles alive at all.

We got back to the boat around 1:00 a.m. which is a late night for a cruiser.  Interesting tour and we would recommend it.  Again, sorry we couldn’t get any decent photos.

Sunday morning we learned that 4 other boats were leaving for Isla Margarita.  These people had originally planned to leave Tuesday night and we were hoping to travel with them, but the weather predictions had changed and another tropical wave was due in on Tuesday.  Tonight there was a weather window between tropical waves so it was a good time for that passage.  So we opted to head to Margarita with the rest of the group.  We should have waited in Grenada until we got all the claim form paperwork sorted out for my recent ATM fraud problem, but we decided that we could sit there for weeks waiting on the bank paperwork.   

The smallest boat left Prickly Bay, Grenada, about 11:00 a.m. and the next largest left between 12:30 and 1:30 p.m.  We started out of the harbor an hour later and immediately turned around and re-anchored.  Yesterday we had replaced our mainsail outhaul because Bill had noticed that it was badly frayed due to chafing.  He brought a sample of the line to Budget Marine and purchased replacement line.  It was supposed to be the same diameter line and also supposed to be the non-stretch type of line.  Budget Marine screwed up on both counts, but we did not know this until we tried to put out the mainsail.  That new outhaul stretched immediately and also went down into the winch----it was the stretchy type line and also was too small a diameter.  When not in use it appeared to be the same diameter as our original non-stretch line, but as soon as pressure from the sail was applied then the line would lengthen and diameter would reduce.  This would slip in the winch.  So, back to the harbor to re-anchor and find a solution.

We searched through our locker of spare lines and found some line that would suffice for the time being, and Bill made another outhaul line and whipped the ends into place.  This line is also too stretchy but it is better than what Budget Marine sold us yesterday.  We again pulled anchor, put out the sails and left Prickly Bay about 3:15 p.m.  It was motor sailing for about a half-hour through the worst of the “washing machine” effect on the south side of Grenada, then we had a fantastic sail all the way to Isla Margarita.  Waters off the southwestern end of Grenada are shallow and the equatorial current causes waves to set-up in that area.  It is not a pleasant area in which to sail or even to motor.  Once past that area and into deeper water, it was just fantastic.

This is what we signed up for!!! We had about 18 hours sailing with 18-20 knots true wind off our port stern quarter with following seas.  Sailing just does not get any better!  We were sailing flat and fast.  The equatorial current was in our favor, causing our SOG (speed over ground) to be 9.6 knots or higher for most of the passage.  We maintained this great speed until near Isla Margarita when the winds died way down and our SOG slowed to only 4 knots.  This caused our total trip average speed to be only 7.8 knots, but that is still a good average speed for any passage.  We had the genoa poled out and preventers on both the main and the mizzen.  This enabled us to stay true to our course and sail the entire way.  All the other boats in our little flotilla had to motor sail the entire way because they did not have a spinnaker pole or preventers.  Actually, one boat motored the entire way with no sails because it is a trawler and has no sails.  Surprisingly to us, even the 44-ft Lagoon catamaran could not hold this downwind course and had to motor sail, and only averaged slightly more than 6 knots, compared to our 7.8 knots.  And this is the type sailing that catamarans where supposed to excel.

Even though the others had left several hours earlier than us and motor sailed the whole way, we still arrived in Isla Margarita at the same time.  And the smallest boat (a Baba 35) had left 4 ½ hours before us; motor sailed the entire way; and still did not arrive until an hour after us.

Bill again did not sleep well on this passage, but he did manage to sleep about 4 hours total; so that is a big improvement for him. 

As we approached Isla Margarita we heard Rick Johnston on S/V PANACEA on the VHF radio.  Rick and Sue beat us here!  They arrived last week from St. Martin where they had a lot of boat work done preparing their boat for a circumnavigation.  They came over for sundowners this evening and we learned that their plans are similar to ours, except that they might spend a year doing the western Caribbean before transiting the Panama Canal.  At any rate, we will certainly meet up again along the way.  We might even be doing the Curacao/Aruba to Cartagena passage about the same time.  It would be great to have a buddy boat for that passage.

We spent all of today on the boat, cleaning up and resting after staying up most of last night.  Tomorrow we officially clear into Venezuela.

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