May 23rd, 2003; Leg 7, Day #1

The transit cruise from the tip of Baja California Sur to Monterey Bay.

Today is our first whole day at sea, and the last day for the R/V Western Flyer in the Gulf of California—home away from home for the MBARI ship since early this year. Derek Greenwood, our steward, traveled to his favorite fish taco stands and grocery stores in La Paz one last time yesterday in order to stock up on our supplies.

We left the port of La Paz around dusk last night, May 22, and steamed all night toward our first station of Leg 7, Station 15, which is roughly half-way between the tip of Baja and the mainland. A rare treat occurred as we left the bay— we saw rays jumping completely out of the water. Baldo Marinovic, a UCSC researcher, told us that they were called mobilis fish— he dares anyone to prove that they are not just doing it for sheer fun!

While the biological oceanography group sent down the first CTD cast (an instrument package that measures salinity, temperature, and depth, 

along with a variety of other measurements that reveal physical and biological characteristics of the water at our station) of the cruise, our blue water SCUBA diving group "got a move on" in order to be ready to dive between the time the CTD package was deployed and recovered (not a lot of time: ~ 40 minutes). We must suit up ahead of time and pile into the inflatable rib boat (humorously named the Spare RHIB). While waiting, we had the opportunity to watch spectacular flying fish fling themselves out of the Flyer's quick path. These fish are able to leave the water for short periods of time and glide across the water with fins that have evolved to look and act very much like rigid wings.

Darrell Palmer and Paul Ban confer about operations logistics on the fan tail of the R/V Western Flyer before directing the first CTD cast of the day at ~ 9:00 a.m.

Steve Haddock, our fearless dive leader, directed us to perform gelatinous zooplankton transects and collections at three different depths. We are very glad to have Karen Osborn (MBARI/UC Berkeley graduate student) and Shane Anderson (UCSB Marine Science Institute Senior Dive Collector) along with us for these specialized SCUBA dives. Blue water diving (diving where you cannot see the bottom, thus it is blue in every direction you look) requires some special training in order to correctly and safely orient yourself in this dimensionless environment. We were all tethered to each other via a central weighted down line, so that we wouldn't unknowingly sink past our collecting depths. The visibility today was incredible, and our whole world underwater was a magnificent deep blue. The water was so warm we probably did not need our heavy wet suits— but we will tomorrow!

Crew members Erik Thunstrom (on the Spare RHIB), Dan Camp, and Pete Zerr (on board) help get the divers safely into the water. Does Steve know his hard hat is on backwards, or is this a fashion statement?

Steve believes that we will see very marked changes in the gelatinous zooplankton community between today and tomorrow when we past the end (or cabo, in spanish) of Baja California and travel into much colder Pacific Ocean waters. We observed many species of pteropods, heteropods, siphonophores, salp chains, and larvaceans, but there is a surprising dearth of hydromedusae and scyphomedusae. The Gulf of California is a more protected area (from open ocean swells) than where we are headed tonight— the water temperatures have dropped dramatically since rounding the point near Cabo San Lucas, and the Flyer is starting to roll a bit.

A pod of playful dolphins out chasing large fish in this region came over to ride the bow waves before our second dive at 3:00 p.m. We considered this a good luck sign.

The biological oceanography group will have their first long station tonight at 2:00 a.m.—no rest for the weary, since they have been hard at work all day long setting up experiments and making sure all underway systems (some designed to sample iron) and the CTD packages are ready to go. An underway system means that there is a constant flow of pumped water to sensors on board the ship while the ship is steaming, thus providing us with a continuous output of measurements at anytime during the cruise.

Ginger Elrod says she is getting ready to start the compressor to pump water for Ken Johnson's Iron Fish tomorrow, while Mike Burczynski reports he is efficiently working through the last "bugs" of the CTD and underway systems.

Zanna Chase, a postdoctoral fellow at MBARI is hard at work prepping for iron experiments organized for this transit cruise. She and her colleagues are interested in observing latitudinal gradients (from Baja to Monterey) in iron concentrations and their effects on phytoplankton primary production in these regions. Zanna has a big smile in this picture—perhaps it is because we keep calling her "Mrs. Strutton" and asking to see her ring again (wink).

The Mexican observers for this cruise leg are Sonia Valle and Marcos Martinez. We have had great fun showing them around the ship and learning about their research interests. Sonia hails from Ensenada, Mexico, so we will be traveling past her home port in a couple of days.

At the end of the day, during the gorgeous Baja sunset, Baldo Marinovic spotted a sailfish's fins and tail tips near the surface of the water near the ship. Big fish abound in these waters...not a bad way to exit the fascinating waters of the Gulf of California.

– Christy Herren
   MBARI Postdoctoral Fellow, working with Steve Haddock on bioluminescent distributions of plankton