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Moonstruck

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Nov 27, 2008
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USA
Vessel Name
Moonstruck
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Sabre 42 Hardtop Express
Just an observation made on our recent cruise to the Bahamas, and return to the Florida East Coast. Following are two photos of pilings. The first will be of the pilings on a dock in Man-O-War harbor. Notice the clear water of about 7-8' deep. The second is back at Ft. Pierce City Marina. Notice the darker water, and the growth on the pilings.

Of course being no marine scientist my observations are anecdotal, but it seems obvious to me that the difference is the nutrients carried in the water. The Bahamas being virtually in the middle of the ocean with no rivers feeding into the water is kind of a barren bottom. The reefs and grasses shelter and hold habitat supporting marine life. Other than that the tides moving quickly over the shallow Bahama Banks flush out other nutrients.


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I think Ron mentioned that in the warm season that a diver is needed in his marina every 3 weeks. Same goes for Hilton Head. The waters around the SC and GA coasts are so nutrient rich that the marshes are incubators for all sorts of marine life. Shrimp being a notable one, but all sorts of others. Fish, oysters, clams, crabs as well as barnacles and other marine growth. The big tidal range brings fast currents that transports the food to sustain the marine life as well as the stuff we love to eat.
 
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One of the things I learned (and remembered) from my marine biology 101 class at the University of Hawaii is that that bluer the water, the less "life" there is in it. By which is meant microscopic life like plankton, tiny shrimp, etc. For example, in Hawaii, the food chain in the open ocean is not very long. There is some plankton but not enough to support huge populations of tiny critters. So you have some baitfish that eat the tiny critters that are there are and big predator fish that eat the baifish (and each other) and that's about it. The water is blue and very clear, although not as clear as Don's first shot. A healthy coral reef has more of a food chain but it's confined to the reef environment.

But in the PNW, the water is green and you can't see very far down even when there's no mud in the water from rivers and such and the water is "clear.". But the food chain in the PNW is huge, from tiny plankton and algae to clams and mussels and oysters to tiny fish to crabs and shrimp to little fish to fingerlings to herring to salmon to seals to whales.

Another example---- there are no seagulls in Hawaii, despite the sound tracks of TV shows like the original Hawaii Five-O and McGarret (the sound editors in LA didn't realize there aren't any seagulls in Hawaii). This is partly because there is virtually nothing natural for them to eat. They are scavengers but the beaches in Hawaii are clean and pristine. A few straggles of seaweed here and there and that's it. As opposed to the huge garbage dump of kelp, dead fish and sand crabs, clams, mussels, and all sorts of other food that gets washed up constantly on the shorelines around here. (Not counting the rubbish that man adds to the count.)

The seagull's scavenger role in Hawaii is filled by the mynah bird. There are lots of seabirds but they spend their lives fishing out at sea.

So clear water, not much life there.
 
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Murky and presumably productive waters here. At least they provide a living for the seal and the two fishermen operating the trawler in the immediate area.

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One of the things I learned (and remembered) from my marine biology 101 class at the University of Hawaii is that that bluer the water, the less "life" there is in it.

That is a good observation, Marin. The next picture is of the blue water surrounding the Bahamas. Other than in the floats of sargassum weed, there is little to support marine life in the upper levels of the very deep waters. The fish that live there are pelagics. They are fast swimmers like Tunas, marlins, sails, swords, and mahi mahi. There are occasonal pods of bait fish that attract these hunters. The water is cobalt blue, and it looks like you can reach into it.

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Yea i know what you are saying staying in Suart last winter when i returned to NC and had the boat serviced and the bottom cleaned. the diver said " man what the heck its like a floating reef of growth on here ! the warm water of the indian river and the not to clear water made for a great place for everthing in the world to grow on the bottom. the dingy had hair 6 inches long hanging off the bottom :)
 
I have always wondered if an experienced eye could look at a boat in marina and tell generally how long it has been sitting...
 
In the Bahamas we could see bottom details (like discarded breakfast eggshells!!) down 30 feet. On returning the the US, I could barely see my own feet in the water!!
 
In the Bahamas we could see bottom details (like discarded breakfast eggshells!!) down 30 feet. On returning the the US, I could barely see my own feet in the water!!

And with that said....Welcome home! :pirate:
 
In the Bahamas we could see bottom details (like discarded breakfast eggshells!!) down 30 feet. On returning the the US, I could barely see my own feet in the water!!

In the Neuse and the Trent Rivers, the water is so dark, even light cannot escape. :facepalm:
 
A tranquil moment on San Pablo Bay, with only ripples and the boat's wake.

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That scene is out of character for San Pablo Bay and San Francisco Bay flat land!

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Hey Mark, those wee little ridges on the horizon.... Those are the dikes that hold in the rivers, right?


:)
 
Hey Mark, those wee little ridges on the horizon.... Those are the dikes that hold in the rivers, right?


:)

Correct. They funnel the collective rivers (what's not pumped south to agri-business and southern California gardens, and pools) into the Pacific Ocean.
 
That scene is out of character for San Pablo Bay and San Francisco Bay flat land!

Strangely, this has been typical for most of my voyages between Richmond and Vallejo. Yes, I've seen rough times on San Pablo Bay. Most frequently between Mare Island Strait and the Carquinez Bridge at the far end of the fetch of SP Bay.

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Bottoms have to be cleaned monthly in FL, and I would recommend monthly in Bahamas as well, as there the growth is different, more hard shell, and this is with the best bottom paints available even outside the US, more slime in FL and grasses
 

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