So, I realize that the collecting trip looks like it's all fun and leisure ... and it is for the most part; our work is fun work, but with a VERY healthy dose of safety. Today's dives really highlighted the precautions we take when diving. Up until today our dives had been no deeper than 45 ft., but today we found a new dive site. When we swam down and hit bottom our gauges read 77 ft. We were all looking at each other with that "whoa" look on our faces (which looks really different through a dive mask.)

But why does going deeper require more caution? There's something about nitrogen I don't quite understand, but I just spent an hour talking with Captain Lou (a VERY experienced Dive Master) to try and understand why we stop and hang out in one spot for a few minutes on our way to the surface.

Here's my layman's attempt to explain it. The deeper you go, the more pressure is put on your body. Oxygen still moves through your body as you inhale and exhale, but for some reason, nitrogen tends to build up and not flow through your body the way it should. Coming to the surface slowly (a gradual release of pressure on your body) allows your body to gradually reabsorb and release the built up nitrogen.

The deeper you go, the more it builds up, and the more time you should give you body to readjust. If that doesn't make any sense, please do not hold it against Captain Lou, he tried his best to help be understand. On a side note ... We also bring the fish we've collected to the surface very slowly by leaving them in a barrel underwater and slowly raising it onto the boat. Fish have a swim bladder, an air filled sac, that controls their buoyancy in the water. If we bring them to the surface too fast, the air in their swim bladder can expand, causing them to float and tilt to one side. Not good.

Okay back to safety. I do know this about deeper dives ... it's darker, and you're further from the boat which makes it harder to orient yourself and make sure you haven't strayed too far. When diving at any depth there may also be currents that can cause you to slowly drift away. As a precaution we always dive with a buddy, and we always take a compass reading so you know which direction to swim to get back to the boat.

We also have a safety observer for every dive. The observers job is to watch for anyone coming to the surface in distress. I almost always look distressed when I surface because I'm winded and my mask has usually filled with water, and everyone knows it now, but everyone still checks to make sure I'm okay. That's good safety.

-Bronwyn

To help with today's blog I have asked Sarah Taylor (at right) to join me. Sarah is an Aquarist at NEAq in Boston and the Trip Leader for our current expedition. She is also a very experienced diver.

Bud: Sarah, why do we do these collecting trips every year?
Sarah: We do them to replenish the fishes and invertebrates in our Caribbean reef exhibits. Simply put, we are replenishing species that die off because of their natural mortality rates.

Bud: Do we need a permit to collect in the Bahamas? Are there any restrictions on what we can take?
Sarah: Yes. We work very closely with the Bahamas Ministry of Fisheries. A Bahamian official comes on board during the trip. He monitors our collecting techniques and examines our "catch." We don't take anything on the IUCN Red List - or anything that is endangered or threatened.

Bud: How is the trip going so far in terms of what we want to bring back to Boston?
Sarah: We're happily ahead of the curve! We actually have more fish on board then expected at this stage. Great!

Bud: Are we harming the reef ecosystem by pulling out these fish and invertebrates?
Sarah: We only use nets; no chemicals. We carefully avoid damaging the corals. And, we take only a very, very small number of animals relative to the size of their populations in the wild.

Bud: How will life in captivity for these animals differ from life in the wild?
Sarah: They will be very well fed and very well cared for by the staff in Boston. Generally, they live longer and grow larger than in the wild. And, of course, because any potential predators (e.g. sharks) in our tanks are well fed, their usual prey has a much better chance of surviving longer.

Bud: How does a collecting trip like this one support marine conservation efforts in the Bahamas?
Sarah: We do species and abundance surveys to help monitor the biodiversity of the reefs. We share our data with REEF (Reef Environmental Education Foundation), an organization that is working to protect the reefs throughout the Caribbean.

Bud: And, by exhibiting these animals in the New England Aquarium in Boston, we teach people about the importance of reef conservation.

Today's best finds:
4 Tobacco Fish (4-5 inches) Serranus tabacarius
1 Trumpet Fish (11-12 inches) Aulostomus maculatus (above right)
2-3 Yellowhead Wrasse (5 inches) Halichoeres garnoti
Several Fairy Basslets (1-2 inches) Gramma loreto

All in all, a great day down here in the Bahamas!

Temp: 85
Skies: Clear
Seas: Calm
Underwater visibility: Fantastic!

After a check-in dive (to get familiar with the local waters) and a teach-in on the ins and outs of catching fish with vinyl nets on a stick (somewhat like using a butterfly net while 25 feet underwater), we headed to Three Sisters Rock just offshore from Bimini for the major event of the day. The goal: to round up several dozen French grunts (Haemulon flavolineatum) and smallmouth grunts (Haemulon chrysargyreum shown at right).

This was an unbelievable experience for a diver like me, since I was only recently certified. The basic strategy goes like this:

Four to five divers station themselves around the perimeter of a barrier net (somewhat like a seine net). Then another group of divers wielding vinyl box nets in outstretched arms attempt to herd a large--make that very large--school of grunts in the barrier net. It looks kind of like the old safari movies when the "beaters" drive the big game into the sights of the waiting hunters, except our task really is to bring 'em back alive.

Once the grunts are in place, the divers gradually encircle the fish with the net. Then, using the vinyl box nets, five to 10 fish at a time are transferred to the nearby "grunt hotel," about 10 yards away. The experts then select the desired species to share with our visitors back in Boston, while gently letting the others go.

And a good day it was. The tally for the dive: 38 French grunts and 17 small mouth grunts. And a special bonus: one spotted spiny lobster (Panulirus guttatus) and one Caribbean spiny lobster (Panulirus argus) Both are clawless version of the Homarus americanus we're all used to in back home in New England.

There was another terrific treat upon returning to the boat. We discovered chef Mat had prepared crab rangoon for our afternoon snack. (From sustainable sources, of course!) Very tasty!

Captain John then fired up the engines for the 7 hour trip to the Berry Islands, 80 miles east of Bimini. We look forward to a great day tomorrow, and we'll keep you posted on the "catch."