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Tranzition Zone Chlorophyll Front

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  The North Pacific Transition Zone Chlorophyll Front (TZCF) is   a dynamic, basin-wide feature characterized by rapidly changing chlorophyll concentrations, temperature, and nutrients , marking a boundary between subtropical and subarctic phytoplankton communities, and influencing marine ecosystems and fisheries.   Here's a more detailed explanation: What it is: The TZCF is a zone of surface convergence where cool, vertically mixed, high chlorophyll water on the north side sinks beneath warm, stratified, low chlorophyll water on the south side.   Location and Movement: It spans the east-west extent of the North Pacific and moves seasonally northward and southward within the North Pacific Transition Zone between 30°N and 45°N.   Seasonal Dynamics: In the fall and winter, the TZCF moves southward, potentially due to strong winds moving nutrients across the boundary between gyres.   In the spring, winds lessen and nutrient transport southward is reduced, caus...
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Bycatch Loggerhead Satellite Tagged

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visit the Usa web site 3/24/2025 Update of tracks for 581 and 583 after 78 days at sea. 581 has become entrained in the strong north-northwest flowing Kuroshio current running and ~3 kts/h.  Turtle 583 is just about to enter the Kuroshio current also... we will see if 583 begins to move northwest also. 3/6/2025 Loggerhead turtles 381 and 583 continue to transmit after 60 days.  They have moved into the same general area ( see map ).  Below are two graphs showing the SST that the turtles have experienced during their travels. I have created an overlay of Chlorophyll a concentrations on the tracks of 581 and 583 and note that they are in relatively productive waters at this time. SST for turtle number 581. SST for turtle 583 2/13/2025 Turtles 581 and 583 continue to transmit after 39 days at sea.  581 has followed the meandering Kuroshio current to the north while 583 has broken out of the Kuroshio current and headed to the south.  Both remain in waters that are 1...
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Post Nesting Loggerhead Turtle Tagged and Released

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  AUGUST 8, 2024 POST NESTING LOGGERHEAD SATELLITE TAGGED  KOCHI BEACH, JAPAN The post-nesting loggerhead is now meandering around an area that appears to be very favorable for her. Loggerhead turtle 571 has begun to remain in the same vacinity which indicates that she has found an area that provides a bountiful foraging area. 571 has moved a little off shore and may be moving out into the Kuroshio current.  Stay turned to see where she goes! Above is an image of loggerhead #571 nesting on Kochi Beach taken by Noah Yamaguchi with a drone mounted IR camera at 0200 hours on August 6,2024.  A team from Usa Marine Biological Institute was able to capture her after she finished laying eggs. 571's eggs (110 in number) were retrieved and placed in the protected hatchery on Kochi Beach.  If these eggs hatch successfully, they will constitute the fourth cohort of STRETCH turtles scheduled for release in 2026!   Post nesting loggerhead turtle #571's locations an...
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DAILY UPDATES ON COHORT II LOGGERHEAD TURTLES

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Noah and Catherine are the STRETCH representatives taking care of the 28 juvenile loggerhead turtles in cohort II of the STRETCH experiment.  They will be providing daily updates on the status of the turtles as they make their way across the Pacific to the area where they will be released into the central northeast Pacific Ocean.   The location of release will be as close as possible to where cohort I was released (~39 N and 146 W) , Noah and Catherine in their STRETCH T shirts during "loading day" when they loaded the 28 satellite tagged juvenile loggerheads on-board the Firmament Ace at the Port of Nagoya. Graphic of ships location and sea surface temperature. The latest update will be at the top of this post 7/8/2024 Twenty Eight Loggerheads were safely released from the Firmament Ace between 1410 and 1445 h (UTC-11) at  39°33.4669' N 148°29.7291' W.  The sea surface temperature was  18℃. See Pictures below of Catherine, Noah and the turtles.   As of now...
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