Deep Chit! - Strange Algae at 210 feet

[SpearMax]

I've been hunting one of my favorite technical areas recently and observed this strange algea that seem to be expanding. The first image is about three months ago. The next images are from Sunday June 17, 2007 when I noticed these octagon shaped patches in the algae.

[SpearMax]

The collection point was at 207 feet as can be seen on my Cochran computer. The samples were from the main algea and the bright spots.

[SpearMax]

I gave the samples to my friend Scott Hurley who works at Force E Dive shop on Sundays and Harbor Branch Oceanographic Institute during the week. He will have it analyzed and let us know what it is. His initial thought is that the bright spots are where the starfish have been eating the algea. I am curious to verify what kind of deep water algea it is. Maybe there is some sort of pollution from a previously unknown break in the fresh water aquifer under the sea bed or something like that or it could just be a naturally ocurring phenomenon. :confused:

[SpearMax]

Oh...here is a stone shot I did on Saturday at 230 feet that resulted in that old familiar spinning tumble. :tongue:

[SpearMax]

I strung the fish up with a spike and leader attached to a lift bag. I did not send the lift bag up right away because a big sportfishing boat was directly above me.

And in a stoke of brilliance (or was it narcosis) I took off with the lift bag, but left the fish on the bottom!

I had detached the monofilament leader from the lift bag. :slap:

[SpearMax]

I realized my mistake in about thirty seconds and immediately returned. But, the dead fish had vanished! :eek:

Guess what....I have been planning on getting TriMix certified in the next few weeks. ;) Maybe the timing is good. :cowboy:

[mjphawk]

Great report. Sounds like a lot of fun. Sorry you lost the fish, but it's not that bad if the worst thing that happens to you while doing a difficult dive like that is loosing a fish. I am sure you will get plenty more.

[keezdiver]

nice pics of the fish....funny story with it.

as for that algae....its weird...

in the bag it looks like any other red algae (Rhodophyta)...or maybe brown (Phaeophyta).

will be interested to see what your friend comes up with.


i will say this. i've done dives in deep water (albeit not 200ft) off the keys and seen several times HUGE blooms of filimentous red/brown algae on the reef. some of it so thick you can't see the rock or sand. it seems to be somewhat seasonal...probably temp and nutrient related. since it disperses later in the year.

could just be a timing thing, upwelling or something.

[SpearMax]

it seems to be somewhat seasonal...probably temp and nutrient related. since it disperses later in the year. could just be a timing thing, upwelling or something.

Jeff, it has been accumulating for quite some time now. I wiould have to check my videos, but I'm thinking 8-12 months at least. We will have to see what this summer's cold-waterupwellings do, but I am thinking it is fed by fertilized nutrients from the aquifer. We will have to see what Brian LaPointe at HBOI says as he is our resident expert along with his colleages. Tony :cowboy:

[Johnoly]

......it seems to be somewhat seasonal...probably temp and nutrient related. since it disperses later in the year.
could just be a timing thing, upwelling or something.

That's what I was wondering. Tony did you hit any thermo's down there? The 80-90 ft reefs were running 78-79 degrees over the weekend. We saw some of the algae late last year when the waters got cold, but haven't seen it on the shallow reefs yet.

[SpearMax]

That's what I was wondering. Tony did you hit any thermo's down there? The 80-90 ft reefs were running 78-79 degrees over the weekend. We saw some of the algae late last year when the waters got cold, but haven't seen it on the shallow reefs yet.

John, sometimes there are thermos down there. For example, last weekend was 72 degrees below 150 feet. This weekend, there was little difference throughout the water column. Tony :cowboy:

[FredT]

Similar algae bloomed in about '73-'74.

Sea Hares and fighting conch bloomed right afterward and the algae disappeared. The two events may even be related..


BTW there amy be an octopus or eel in the thruster... that would explain the rapid departure of the fish.
FT

[SpearMax]

Similar algae bloomed in about '73-'74.

Where did that happen? :confused:

[bfsc]

I doubt it has anything to do with your aquifer theory. The aquifer system in our area does not work that way. It is actually opposite of what you are thinking. Which is one problem with the drought. As more fresh water is drawn from the groundwater and as the groundwater table lowers it causes the saltwater to creep west into the freshwater drinking supply (saltwater intrusion).

[cavehunter]

The problem is nutrient rich water that is deep well injected by the coastal municipalities at a depth of 3000 ft. This aquifer is separated by clay confining layers from the aquifer that we draw our drinking water from. We believe that these clay confining layers breakdown offshore and provide a supply of nutrients to these deeper reefs.

[SpearMax]

The problem is nutrient rich water that is deep well injected by the coastal municipalities at a depth of 3000 ft. This aquifer is separated by clay confining layers from the aquifer that we draw our drinking water from. We believe that these clay confining layers breakdown offshore and provide a supply of nutrients to these deeper reefs.

Exactly! I look forward to the analysis of the algea.

[bfsc]

That might be the case. But, if that is the case then why wouldn't there be breakdowns of the clay layer over the land? or is there? It seems like there wouldn't be that big of a difference between land and a couple of miles offshore. But maybe ther is.

[SpearMax]

That might be the case. But, if that is the case then why wouldn't there be breakdowns of the clay layer over the land? or is there? It seems like there wouldn't be that big of a difference between land and a couple of miles offshore. But maybe ther is.


CaveHunter is Scott that works for HBOI who I gave the sample to for analysis. Scientist Dr. Brian Lapointe is one of the world's experts on these things and has been studying our area here off Palm Beach for years.

See this link: http://www.hboi.edu/news/features/lapointe.html

I too want to learn how that whole aquifer thing works. This should be interesting to find out what these scientists think about this algea. :cool:

[bfsc]

I have a pretty good understanding of the aquifer system, but I defnately do not know everything. It would be interesting if you do find something. I am in the water treatment business.

In my head, I was thinking there are wells probably less then 5 miles away that go down maybe 200' and they are all over south forida, and to the best of my knolwedge nothing has been found in any of the wells to indicate this. Let us know what you find out.

[Summerland Key]

I am afraid that Scott is correct on the nutrient upwellings. Injection wells just never seemed like a good idea to me. Injecting nutrient rich effluent into the ground and expecting it to stay there forever is not realistic thinking. It is a time bomb waiting to go off. Algae is a marine plant, fertilize it and it grows. Scott and Brian would have the data on this one. It is right in their back yard and I am sure research has been done. Don

[cavehunter]

This macroalgae is definitely a rhodophyte meaning that it is a red macroalgae. It has simple branching pattern which are delicate, fine and filamentous. It closely resembles a shallow water alga (Aglaothamnion cordatum) that grows on other algae but it isn't found this deep. I did find some sexual reproductive cells called tetrasporangia that were similar to above mentioned alga. The sample will probably have to be sent out for definite identification. I included some micrographs that I took with a high powered microscope to help in the identification process. Another interesting point was the color change in the mat of algae was caused by the grazing of the large starfish on the wreck.
Cheers,
Scott Hurley

[cavehunter]

I thought this little cartoon would help with the process that were involved with Submarine groundwater discharge (SGD). Idealized land-sea interface, showing various SGD processes and scales.

[SpearMax]

Hey Scott, that is great information and shows how we humans may be affecting the ocean in this case if it is caused by deep discharge. I will pass this along to the County people. Thanks, Tony :cowboy:

[Summerland Key]

Scott:

Thanks for the information. The drawing clearly shows how ground water can make it offshore. Don

[Chad Carney]

Tony,

In the confusion of shooting a big fish with multiple spears, I left a perfectly good spear on the bottom once in about 190'. I realized it at about 130', but wasn't about to drop for it and add a stack of deco time...

But I've never left a captured fish on the bottom!! :D

You are definitely overdue for trimix!

Chad