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Showing posts from June, 2008

eagle ray researchers are here

sorry - no photo - was at airport all day fetching the eagle ray guys...

will get them to post a article asap - once we get the sonar trackers in place etc

Photo Friday

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Tarpon Hole, an MPA site on the Southern reef edge,
is a nice shore dive that can be reached
by swimming straight out from the public steps
at Elbow Beach. It provides a dramatic
dive and is great for UW photography

Busy summer ahead

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BREAM volunteer research associate Mike Colella,
checks out the reef between surveys.
(c)2005 T.Murdoch

Summer is here and BREAM is heading out into "the field"... well - the sea, really...

Next week DISL PhD student Matt Ajemian is returning to continue his BZS-supported research on Bermuda's eagle rays - link.

The week after, we are hosting a group of visiting scientists who are here on a field trip, sponsored by the Atlantic Conservation Partnership, the Tourism Department, the Department of Conservation Services, and the Bermuda Zoological Society, and supported by Triangle Divers and the Grotto Bay hotel, to learn about Bermuda's coral reefs and associated marine habitats - as part of the 11th International Coral Reef Symposium (ICRS) - link.

The next week we all dash over to Ft. Lauderdale, Florida to attend the ICRS. We are presenting 3 posters and 1 presentation on our research projects on Bermuda and Florida reef and fishes, with the following titles (* = present…

Video Friday

Here is a nice little video of a massive school of fry being worked by a gang of black grouper, snapper and rainbow runners that we came across in a Marine Protected Area last year.


New Links - Bermuda Diving and Bermuda Sub Aqua Club

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Black Grouper at a Protected Spawning Aggregation in Bermuda.
(c) Bermuda Diving

Just added a link to Bermuda Diving. A great website that has awesome photographs of coral reefs, ship wrecks, big ol' fish and useful information about the wonderful diving scene here in Bermuda.

Also just added a link to the Bermuda Sub Aqua Club.BSAC is the only national club for scuba diving enthusiast. They are affiliated with the British Sub-Aqua Club, and also welcome members who are qualified to PADI, NAUI, and other standards. If you are interested in diving with them, learning to dive, or just want to check out their club, come visit them at Admiralty House, Spanish Point on Wednesday nights.

Check 'em out!!

Rim Reefs and Reef Passes

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A view across the shallow rim reef. (c) T. Murdoch

Between the outer forereef and the inner lagoon of the Bermuda Platform lies the "Rim Reef" - which is only 5 ft deep in places and which forms the protective barrier that large waves break against.

Cutting through the rim in 30 to 40 places are deep cuts, or passes, that reach down to 40 ft or deeper and 60-ft wide or less. It is through these passes that a lot of water transfer occurs between the lagoon and open ocean.

Many of these reef passes are favourite dive sites, including: Eastern Blue Cut, Western Blue Cut, and Snake Pit. Turns out the pleasure divers had it right, as our research surveys over the past 4 years have shown that fish populations are much higher and there are more species found around passes than on the shallow rim reef spots between passes. Conversely, coral cover tends to be higher on the rim, with lower cover but more species found in the deeper passes.

A BREAM scientist swims along a pass between
the N…

As human-created CO2 increases in the air, so does the oceans acidity

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Regardless of whether increasing carbon dioxide (CO2) will cause global warming, we know it will cause the oceans to become more acidic.

Corals and shellfish and calcareous algae, such as in the image below, rely on a low-acid ocean to produce their skeleton, and if the oceans become more acidic these animals and plants will not be able to grow properly.
The native Top Shell snails, and the pink calcareous algae in this tide pool,
rely on a stable and alkali ocean chemistry that is now being made
more acidic by anthropogenic CO2. Image (c) 2007 T. Murdoch

The only way to safely remove the additional CO2 that we have added to the atmosphere is to reduce emissions (exhaust) from cars, factories and other petroleum and coal burning sources.

You can read more about this global problem here (New Scientist) and how local scientists at BIOS are researching it here (BIOS).

Corals are Colonies of Polyps

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The hard and soft corals that make Bermuda's reefs are made up of many separate polyps, which are like individual little sea anemones.



Anatomy of a coral polyp (c) NOAA

The polyps are distinct in some corals, such as the "Massive Star Coral" shown in the close-up below.

In other corals the polyps form in linear series, so that the individual polyps are hard to see. Brain corals do this, and in the photo below you can see the separate polyp mouths, indicated by arrows, that are inside the groove formed by the row of joined polyps.


Each polyp is an exact copy of its sisters, and what we think of as individual corals are really colonies of these clones all living and coping with the environment together.

The Bermuda Turtle Project

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Today we are posting an update from Mark Outerbridge about the Bermuda Turtle Project - an affiliated project not under the BREAM umbrella, but also happening at the Bermuda Zoological Society and the Bermuda Aquarum (BAMZ).

You can learn much more about this 39 year conservation project at the web address for the Bermuda Turtle Project - which is: http://www.cccturtle.org/bermuda

The Bermuda Turtle Project continued in its thirty-ninth year and is still very committed to the goal of promoting the conservation of marine turtles through research and education. Project activities during 2007 included field and laboratory research, training of international and local students, participation in the Annual Symposium on Sea Turtle Conservation and Biology, and public education via presentations, classroom activities, local media, and the Bermuda Turtle Project webpage. The following as a brief summary of the major findings in 2007:A total of 200 green turtle (Chelonia mydas) capture…

Bermuda is bigger than you think

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The boundary of Bermuda's Economic Exclusion Zone, out in the western North Atlantic.

Since 1996 Bermuda is not just a archipelago of islands surrounded by the shallow coral reef - but instead extends 200 nautical miles in every direction from the "baseline". The baseline includes the low-tide mark along the south shore, but then extends out and runs along the shallow rim reef on the north east to southwest sides of the lagoon.

This means Bermuda is not 21 square miles any more, but really covers +180,000 square miles!!!

Most of that is under water, of course - and about 12,000 feet deep or more! The seabed in our EEZ is not flat either, but studded with deep sea mounts, presumably of volcanic origin and probably covered in fish and benthic creatures.

The bathymetry of Bermuda's EEZ has been mapped, albeit at a low resolution.

Moon Jelly

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A moon jellyfish, Aurilea aurita, which form extensive congregations during warm summers in Bermuda. Image (c) 2006 T. Murdoch