A stunning place for field work, one of Fernando de Noronha's beautiful coves is ringed with lava rock and vibrant green vegetation. At high tide, the expedition sealed this cove with a seine net, attempting to capture lemon sharks.

6:45am, March 28, onboard a local fishing boat -- A few minutes ago, one of the crew members shook me awake from a short, but much-needed slumber. I grabbed my camera bag and hastily stumbled onto the deck of the Research Vessel SEWARD JOHNSON (RVSJ). I was disoriented and clueless to the situation...I was being sheperded toward a small, local fishing vessel with four other researchers.

Gradually, as we motored away from the RVSJ, my post-nap haze began to lift. We were making our way around the island, bobbing erratically on the small boat...one of the scientists told me that we were the morning's appointed shark scouts. Rather than spending our last precious day of research getting to know the local sea, the team had hired a fisherman to help us find adult lemon sharks. On the far side of the island we dropped anchor, I came more or less fully to consciousness, and we fished.

As the hours passed and the baited lines dangled untouched, the quick-rising sun began to burn our skin. In the rush to get out here, no one had remembered sunscreen. To keep our minds off of our reddening faces, we babbled about birds and home and the meaning of Portuguese shark names.

12:00pm --It was now obvious that our morning was going to be entirely fishless. Our unmolested, baited hooks were achieving nothing apart from confirming that there were NO sharks around (scientifically speaking, of course, this result could be construed as an information-gathering success). We pulled up anchor and bobbed toward the mainland to meet up with the rest of the expedition.

1:35pm, Fernando de Noronha -- We found a research team at the east end of the island where a picturesque cove sits at the base of lava rock cliffs, covered in the island's uniquely vivid shades of green (I am told that now it is the rainy season, and in a few months this will all be brown).

Most of the team sat on the cliffsides overlooking the sheltered cove. Word was that adult lemon sharks had been sighted down there! After a few minutes, the first shark swam into view. Chief Scientist Dr. Samuel Gruber and one of his fellow researchers, Damian Chapman, made their way into the water, baited hook and line in hand.

The minutes passed and one large shark became three, but they seemed uninterested in food. Lack of hunger is not a good thing when you are trying to hook a shark. But for the researchers who were about to enter the water to net the animals, the fact that they weren't too hungry was welcome news indeed! I heard one of the scientists say, "Someone could really get hurt. These are big animals!"

The netting team went into action, moving into the chest-high water, planning to entrap the sharks by blocking the cove's exit with a seine net. Then, the trouble began.

We started discovering pockets of deep water along the erratic contours of the cove's bottom. These deep spots caused our net to be lifted well off the bottom in several places. Without a good "seal" at the water's surface and along the bottom, seine netting has little chance of success. In the cove's turbid waters, at least one of the net holders had an unwitting close encounter with a shark as the trapped animal slipped beneath the net and moved out to sea.

What started as a final attempt to capture lemon sharks ended as an exercise in net deployment. Moving along a muddy road with their empty nets, the team returned to the boat.

5:00pm, the dock at Fernando de Noronha -- As I send this dispatch, a small group of longliners prepares for a final night of fishing in the waters of Fernando de Noronha. They will spend the better part of the night probing the depths with baited hooks. Tomorrow, we will see how they faired and then we'll begin preparations for our return to Natal, Brazil -- our final port and the end of this amazing expedition.