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Current Cruise: TC-01-01 Coral Reef Assessment January 31- March 01, 2001
February 14, 2001
This week's update comes from less than a mile north of the equator. The Townsend
Cromwell has completed four long intense days of work at Howland and Baker Islands and is steaming nearly due east
to Jarvis Island, almost 1000 miles away. We are bucking 4 to 6 foot seas, 18 knot winds and a 1 knot current. All
together the weather is slowing the ship down to two thirds her normal speed. This can add up to a significant loss
of time over 1000 miles. We are spending the time during the long transit processing the data that was collected
during the four days at Howland and Baker. Here is a brief summary of what's been done.
We arrived at  Baker island in the late afternoon of the 6th and carried two US Fish and Wildlife
Service personnel ashore in our inflatable boat. They camped on the island for four days counting birds, mapping
vegetation, and surveying for toxic materials left behind by the military during WWII.
We then steamed
about 40 miles North to Howland where we started oceanographic operations at midnight. We did CTDs and ADCP
transects around the island to learn more about the oceanographic conditions here. Our day time operations started
soon after sunrise, around 8:00 am. All the boats were launched, loaded with divers and their equipment, and then
sent off for a long day of diving.
The tow-boarders completed their circumnavigation of Howland on the first
day, videotaping the coral reef. The fish and benthic dive teams all did three long dives, studying the fish and
other organisms of the coral reef. The teams also placed two fish traps and 4 sono-buoys over the reef as part of
their studies. The Cromwell set 10 lobster pots as a trial assessment of larger organisms in the deeper waters off
the island. The ship also supplied the dive boats with fresh dive tanks as they needed them. All the boats were
aboard by 7:30 pm and
after cleaning and stowing gear, labeling and freezing samples, and refilling tanks, the
day was at an end by 10:30 pm. This routine was repeated again the next day.
We then moved on to Baker and
started all over again. An additional project took the ship's Navigation Officer ashore at Baker Island to install
a permanent antennae mount and a Global Positioning System (GPS) satellite receiver. This GPS receiver will help to
make the survey positions more accurate and aid in satellite monitoring of the reef. After two full days of coral
reef assessment,
we picked up everyone off Baker Island, secured all our gear and set a course for Jarvis
Island.
It all went well, and we accomplished what we had planned to do. We found that the coral seems to
be healthier compared to last year. The towboard fish surveys
observed an abundance of sharks, jacks and
snappers of many sizes. The dominant sharks were gray reefs and whitetips, with occasional blacktips and a few
hammerheads at both Howland and Baker. Several  manta rays and
numerous sea turtles were observed, particularly at Baker. Spotted dolphins were common at Howland. Only a few
lobster were observed from the towboards. Giant clams were common at both islands
The tow-boarders and
drift divers cover 19 kilometers at Howland and 17 km at Baker. The fish team has added about 50 species to the
list of fish known to live around these two islands. The sono-buoys recorded fish and invertebrate sounds for 24
hours, in areas of live coral and in areas where the coral had been killed off by the last El Nino event. We did 35
CTD's around Howland, and
19 around Baker. The lobster pots produced no lobster but they brought up a few
interesting crabs, sea slugs, and eels. One small white tipped shark found its way into a trap, too. It was pretty
exciting opening the traps with the eels in them. One got loose on the deck and made everybody scramble as it
slithered around with it's mouth wide open looking for something to bite.
We now know much more about
these islands and the coral reefs around them. Protecting and managing these fragile environments requires that we
assess them as they are now and watch them change as they go through natural cycles. We all feel this is important
work and look forward to arriving at Jarvis Island to see how it has changed over the past
year.
Other Updates from this cruise:
Feb 01 Feb 05 Feb 14 Feb 19 Feb 26
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