Saturday, May 14, 2005

Good afternoon from the R/V Nancy Foster!

What an incredible day to be out in Gray’s Reef National Marine Sanctuary! While the morning catches have not been very productive, we could not have asked for better weather.

It is now 1300 hours and the first two traps of the day have been retrieved, and divers have been deployed for the second time in the day. The divers are divided into three motor boats and a ship’s crew takes them to different stations of interest. Once back on the ship, Jenny and Dave note seeing a skate and several sea robins, as well as the usual black sea bass and scup. Some divers have collected video footage of their surveys. (I cannot wait to check out their work environment, here in GRNMS.)

As for the chevron traps, the retrieval of the first trap was disappointing. The menhaden were still neatly tied inside the trap without much disturbance, and no fish were collected. From this data we may infer that few fish reside in the sandy area habitat. Our luck soon changed with the retrieval of the second trap. Sarah F. prepared us for the good news when she and Dave dove near the trap and observed a great abundance of fish at the site, which consisted of densely colonized hard bottom. As she projected, the second chevron trap collected more than 50 lbs of sea bass, one scup, and even a red snapper 44 cm long. Although a large number of fish were caught, the diversity of species seen in catches from last year’s cruise has not been witnessed so far. Perhaps the water is still too cool for species found in more tropical waters, as indicated by Kate’s CTD profiles.

Once the fish are on deck, Athan, Sarah, Kate, and I work as efficiently as possible to “work up the fish”. This consists of removing excess air, measuring the fish, and getting them back into the water, as described in yesterday’s log. The snapper had lots of life in it and fought us the whole way. Yet, he made it back in the water safely, and quickly disappeared from sight.

We are currently waiting for the divers to return so that we can begin the next trap survey. Time on the boat can pass pretty slowly when we are in between stations and surveys. This is a good time for scientists to organize their data, download digital photographs from their cameras, clean gear, write email to loved ones, or even catch a nap. As for me, this is the best time to share my experiences with you.

During our down time, Kate collects another CTD profile; she anticipates the profile will be similar to the first because wind is minimal, and we have not received any rainfall. As for Athan’s research, all of the next three retrieved traps are empty. One might predict that we would have collected some scup in these areas because these fish forage in the sand, unlike sea bass that are reef fish. However, this was not true.

Fortunately, we have four trap deployments scheduled for hard bottom habitats which will hopefully bring a large quantity of fish…as well as keep Athan, Sarah, Kate, and I on our toes.

It is currently time for me to join the rest of my group in the Mess Hall for dinner; it is served promptly at 1630 hours (4:30PM). (Take it from me, meals are not to be missed on the boat. Jessie, the Chief Steward, and Dennis, 2nd Cook, do a remarkable job in the galley.)

I hope you will visit tomorrow for accounts of our exploration of the sanctuary. Please email me at scientist10.nancy.foster@noaa.gov if you have any questions.

See you then,

elizabeth

Gray’s Reef National Marine Sanctuary:
Daily Connections to Scientific Inquiry & Nature of Science

Data Collection

While it is disappointing to retrieve traps that have little to no fish collected inside, it is important to recognize that these are important data, too. This happens frequently in scientific investigations, or alternative occurs where the data that is collected disproves a hypothesis. In either case, the data are still important to document.

In our case, the divers observe few fish in the sandy bottom areas. Therefore, the divers’ observ ations confirm the pattern that Athan is noticing with his trap surveys in the sandy bottom areas of the sanctuary. From this data we may infer that species abundance and diversity vary with distance from the hard bottom habitat.