STRETCH UPDATES - COHORT 2

10/5/2024

Below are the current tracks of our three Splash Tagged loggerheads.

10/3/2024

BREAKING NEWS from STRETCH team member Masanori Mori: "I went to Professor Saito-san's Usa Marine Research Institute to pick up this year's hatchlings of loggerhead turtles, which are the 4th cohort of STRETCH. I am pleased that we have been able to secure hatchlings from wild sea turtles for the STRETCH project for four consecutive years. This means that, as originally planned, we are on track to conduct a total of four releases under the same conditions using hatchlings from wild loggerhead turtles by 2026."

Below are a couple of pictures of Professor Saito, his students (Usa Marine Research Institute) and Masanori Mori ( Port of Nagoya Public Aquarium, (PNPA)).

Some of the hatchlings that will be part of the Cohort IV of loggerhead turtles to join the STRETCH project. They will be release in July, 2026 after they have been raised to an appropriate size at PNPA.

Little Cohort IV turtles being introduced to their new home at the Port of Nagoya Public Aquarium.

10/2/2024

Below is a real-time map of the location of 27 juvenile loggerhead Cohort II turtles of the STRETCH project (Mina has not recorded a locations since 9/20/24). This map only shows the last 6 day's locations in an effort to reduce the clutter caused by 86 days of location data and the associated tracks. We see that the tracks of the 27 are covering much smaller distances indicating that they are in areas where they don't need to travel as far to find food resources.

9/30/2024

Below is the list of our 28 satellite tagged juvenile loggerhead turtles with their total distance traveled since release, the number of hours since their release and their average rate of travel (km/hour). Note that turtle number 568/Mina has not transmitted since 9/20/2024.

9/23/24

All 28 juvenile loggerheads continue to transmit good locations. Below are a couple of images of the 28 tracks relative to sea surface temperature. All of them are keeping within the range of ~18-21 degrees C.

Tracks for our 28 juvenile loggerheads are shown in red. All of them are remaining in waters that are in the 18 to 21 degree C range with most of them in 18-19 degree water.

Co-PI Jeff Seminoff has suggested that the loggerheads that are moving eastward may be taking advantage / following the oceanographic current flow. See video below.

The video above shows the three loggerheads' (with Splash tags) location and the flag at that locations shows the current strength and direction as of 9/23/24.

The locations of each turtle on September 23 is shown above to iliminate some of the clutter caused by looking at entire tracks.

Co- CI Jeff Polovina said the following about their tracks:
"I've attached the latest SST anomaly plot (see below) for the Pacific that shows the classic La Nina pattern with cooler water in the equatorial region indicating strong upwelling with striking tropical instability waves and closer to home strong upwelling off the California coast also indicated by the cooler water. Thus the CC ecosystem is likely more productive this year than last year when El Nino conditions prevailed. Interestingly some of our cohort 2 are now heading directly east toward the CC rather than the much more southerly route taken by cohort 1. Could the eastward heading turtles of cohort 2 somehow detect from far offshore that the CC is more productive this year than last year? "

NOAA's SST anomaly plot for the Pacific

9/16/24

All 28 juvenile loggerheads are still transmitting! In looking at the individual tracks one sees that 20 of the 28 are moving to the east, 4 are moving westward and 4 are "neutral"- neither east nor west. All seem to continue to move more slowly indicating that they are not "searching" but "finding" food in greater concentration.

The three Splash10 tagged turtles seem to have established a nocturnal/diurnal behavior pattern spending more time at shallower depths during the monitoring period from 1500h to 0300h and more time at deeper depths from 0300h to 1500h. Below are graphs showing their diving behavior from September 1 to September 14, 2024.

9/8/24

After 63 days, all of our Cohort II turtles are transmitting successfully and seem to be doing well. They have slowed down which is an indication that they are located in areas where there is food and there is no need to travel longer distances to find it. Below is a short video showing the distances traveled by each of the 28 loggerheads to date.

The average distance traveled is 932 km with a range of 719 to 1178 km. The mean distance traveled / day is ~ 15 km.

Above is a video of the individual tracks overlaid on NOAA's coral reef watch sea surface temperature color map. Each individual loggerhead name and track length is show in the upper left of each frame.

Above is a table showing the distances traveled by individual members of Cohort II as of September 8, 2024.

8/23/24

Our intrepid 28 juvenile loggerheads continue to transmit. They seem to have "turned the corner" and most are no longer headed northwards. Almost all of them remain in 18-20 degree C waters and appear to be moving shorter distances as though they have found areas where the food supply is in greater abundance. Below are the tracks for the 28 turtles and, below that, are the tracks of our Splash10 tagged turtles showing their temperature and depth preferences.

As you can see, most of the turtles have slowed or stopped their northward movement and many have actually turned southeast of sourthwest.

The three Splash10 tagged turtles are behaving similarly to the rest and have begun to loop southward.

Below are the latest (8/12/to 8/22) Charts of the percent of time they have spent at various temperatures and various depth. Ehnaally is currently located in warmer water and, interestingly, is spending nearly 100% of its time on the surface. Moana Kai and Pericu are both in cooler waters and their diving patterns are similar in that they are spending 35 to 40% of their time at depth from 5 to 15 meters. Why Ehnaally's diving patterns are different from the other two is not known. In an earlier post I showed that the diving patterns to depths of 5, 10, 15 meters occurs more frequently at night.

Moana Kai

Ehnaally

Pericu

8/16/24

Looking at the diving behavior of the three Splash10 tagged loggerheads, we see that there is a difference in their diving behavior during the daytime vs the night time. They are spending time at 10-20 meters during the night and more time at the surface during the day.

Are they resting at depth or feeding during the night and, conversely, are they feeding or resting on the surface during the day?

Here are the tracks for Moana Kai, Ehnaally and Pericu.

Moana Kai

Ehnaally

Pericu

8/12/24

All 28 loggerhead turtles continue to transmit locations and appear to be doing "what loggerhead turtles do" in the northwest central Pacific Ocean. The three loggerheads that are carring temperature / depth sensing Splash 10 tags give us a chance to see where they are spending their time relative to depth and water temperature. Below is an image showing the tracks of the three (Moana Kai, Ehnaally and Pericu) for the past 35 days. Below that are three sets of bar graphs that show percentage of time each of the loggerheads spends at water temperatures and depth bins. By comparing the graphical data with the NOAA sea surface temperature color chart you can see that Ehnaally (for example) seems to be spending more time in warmer waters that Moana Kai or Pericu. Note that they are separeted by 100 to 170 km.

8/8/24

Two of our STRETCH team members (Tomomi Saito, Director, Usa Marine Biological Institute, Kochi University and Noah Yamaguchi, PhD student at Kochi University) have deployed a Wildlife Computers Spot 6 tag on a post nesting loggerhead turtle that nested on Kochi Beach on August 6, 2024. Our juvenile loggerheads that have been released in the our STRETCH project all come from Kochi beach. Of course, all the North Pacific loggerhead turtles are hatched on Japanese beaches.

I will keep a post running that highlights this newly tagged turtle as she continues to lay more nests or makes her way back to her foraging grounds. You can view this post at Kochi Turtle #571.

COHORT II CONTINUES NORTHWARD

As of today, Cohort II continues to move north-northeast as the 18 degree C isotherm moves north. They have been transmitting for 28 days now. and all are transmitting normally with the exception of Rosa. We have not gotten a location from Rosa since 8/4/24 so the tag may have malfunctioned or something. It is interesting the the majority of the Cohort is moving a little easterly as they move north. Cohort I's tracks were more directly north with an equal number moving northeast and northwest. Something is different with the oceanography this year.. la nina vs el nino?

8/2/2024

Below is a table of the distances that each of the 28 loggerhead turtles have traveled to date. Keep in mind that their paths are not straight lines and there are lots of twists and turns in their travels that we may miss, meaning that they probably have traveled further that these numbers indicate. Having said that, they have traveled an average of

~483 Km since their release.

7/31/2024

As we race toward the month of August, we note that our Cohort II individuals are staying in ~16 degree C waters.

7/28/2024

Below is a comparison of the tracks taken by Cohort I and Cohort II during the first few weeks after release. Both Cohorts were released in the same general area on approximately the same date (one year apart) and, while the sea surface temperature was cooler when Cohort II was released it was still above ~19 degrees C and they have moved northward generally keeping in 16-18 degree centigrade waters. This behavior tends to keep them in the vacinity of the Transition Zone Chlorophyll Front (TZCF) where food is expected to be more abundant. Both Cohorts are, as expected, behaving similarly for now. We look forward to seeing how Cohort II tracks as the water temperature cools and they begin to move south again. Will they behave like Cohort I did and divide up into two general behavior patterns where the majority will move south or southwest while a small group will move to the southeast and, if conditions are favorable, continue towards / to Baja California???

Cohort II tracks from 7/8 to 7/28 are on the left and the tracks of Cohort I from 7/11 to 7/27 are on the right.

7/25/2024

Three of our juvenile loggerheads are equipped with special satellite tags from Wildlife Computers that log and transmit various behavioral parameters (time at temperature, time at depth, maximum dive depth and dive duration). Below are three sets of graphs showing water temperature preferences and percent of time spent at various depth bins. If you have any questions, please send a note to loggerheadstretch@gmail.com

MOANA KAI

EHNAALLY

PERICU

7/24/2024

It has been 10 days since our last posting and 17 days since the juvenile loggerheads were released into the north central Pacific Ocean. As expected, they have all moved northward and remain in waters that are 16 to 18 degrees centigrade. Below is a series of three screen shots showing the tracks of all 18 turtles from 7/7 to 7/23/2024 and the current sea surface temperatures (SST - https://coralreefwatch.noaa.gov/product/ge/index.php).

Above is a map of the Pacific ocean showing the location where cohort II loggerheads were released relative to the Hawaiian Island and North/Central America. The colored portions represent surface water temperatures as indicated by the legend bar on the left.

Zooming in a little on the figure at the top.

This images zooms in further to show the individual tracks of the 28 juvenile loggerheads and the relative water temperatures where they are currently located. It appears that they are in waters where the temperature ranges from ~15 to 19 degress centigrade.

They continue moving northward and, most of them, are hanging in the temperature band of 17-19 ℃ and perhaps within the transition zone chlorophyll front... hopefully lots of food in that area.

Send Questions to loggerheadstretch@gmail.com

Map of 28 Cohort II Loggerhead Trejectories

17 Legacy Journal Publications That Form the Foundation For The STRETCH Project

PHASE II

7/14/2024

Cohort II continues to transmit locations every other day and they continue to move northward to stay in the water temperature of around 18 ℃.

7/11/2024

The 28 loggerheads seem to have reached an area where they are meandering around, perhaps because they have found some forage items. There are a few that have chosen different paths for the time being and one (Pericu) that has moved further north than all the others. The 25 loggerheads with Spot6 tags are in their off phase for 23 hours and then we will get some more transmissions identifying their location.

STRETCH tag attachment protocol:

Rowan Calder (Wildlife Computers) has written and illustrated our satellite tag attachment protocol and it can be viewed here.

7/10/2024

All 28 turtles have reported in to the ARGOS satellite system today after not transmitting for 23 hours (this is part of our plan to conserve battery power). Below is the current map of their travels since 7/8/24.

As expected they have moved northward approximately 60 km.

The vertical green line on the right represents a distance of 60 km. The sea surface temperature where they are currently (most northerly ones) is between 18-20 ℃

Go to the loggerhead stretch website for this map and the names of the individual turtles.

Japanese TV coverage of Satellite Tag Attachment

Daily updates from Noah and Catherine on-board the Firmament Ace.

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, all 28 loggerheads are transmitting successfully. It will be a few days before we get an idea of what they will do. However, it seems that they are in a water temperature that indicates they may be very near the Chlorophyll Front where their food is most abundant. They may not make a substantial northward migrations like cohort I did when they were released in water that was 6 degrees C warmer last year on July 11. As the water warms, however, they will progably move north to remain in the Transition Zone Chlorophyll Front. Time will tell if that is true or not.

Stay tuned and be sure to visit loggerheadstretch.org to view the map of their movements.

Catherine and Noah celebrate the release of 28 juvenile loggerhead turtles into the Pacific Ocean at 39°33.4669' N 148°29.7291' W

Catherine loads a loggerhead into the lowering basket.

Ready for release.

The loggerhead is gently dropped into the water from the basket.

Noah holding one of the 28 beautiful loggerheads released today.

Catherine holding one of the loggerheads that were released today.

6/30/2024

Fermament Ace has left Yokohama, Japan is on its way to Balboa, Panama. Noah and Catherine are accompanying and caring for the 28 juvenile loggerhead turtles that were loaded on-board the Firmament Ace in Nagoya on June 26, 2024. The ship left Yokohama, Japan on 6/29 and, if you wish to follow its progress towards Balboa, please check in with VesselFinder.

Noah and Catherine in their STRETCH T shirts during "loading day" when they loaded the 28 satellite tagged juvenile loggerhead turtles on-board the Firmament Ace at the Port of Nagoya.

Loading the turtles on the ship:

Firmament Ace Captain and PNPA Director Masanori Kurita.

Noah, Catherine and the Firmament Ace Crew.

FA crew members transporting loggherad turtles to the top deck.

Crew member unloading loggerhead turtles.

Bow area of Firmament Ace.

Juvenile loggerhead number 44 (Named Ehnaally). Ehnaally is carrying a Splash10 297 satellite tag that will give latitude and longitude, depth and water temperature once the tag becomes active on July 7.
‘Ehnaally, means turtle in native Kumeyaay (land stewards of the San Diego area prior to western settlement)

Juvenile loggerhead turtle number 53 (Named Anacapa)
carrying a SPOT 6 satellite tag that will give its latitude and longitude once the tags become active (on July 7)
Anacapa is the indigenous name for one of the channel islands in the Southern California Bight.

6/24/2024

STRETCH team members are now home after a productive week in Nagoya, Japan attaching satellite tags to 28 juvenile loggerhead turtles at the Port of Nagoya Public Aquarium. We attached 7 tags/day for 4 days and now all 28 turtles are resting in their baskets at the aquarium. The turtles will be loaded on the MOL ship Firmament Ace on June 26th and will be accompanied on their voyage by Catherine and Noah (Noah accompanied and released Cohort 1 on July 11, 2023). The ship will, if all goes well, be at the suggested release point by July 9, 2024. If interested in seeing the release technique, Please watch the 2023 release video.

Above is a summary video of the process of attaching the satellite tags to the carapace of the juvenile loggerhead turtles.

Below are the numbers and names given to the 28 turtles

of the Cohort II

6/21/2024

Our trip to Koyo High School was very pleasant. Larry Crowder (STRETCH Co-PI) talked to about 40 students about his career path and experiences and then reviewed the STRETCH project results for Cohort I and talked about our plans for Cohort II. Below is a groups shot of the class and the STRETCH team.

The Koyo High School class, their teachers and the STRETCH team (Larry, Laura and Marc) after the STRETCH presentation.

We have completed the attachment of the tags and we will check on the turtles at the aquarium to make sure everything is fine with them. At 1355 h we will venture to Nagoya Koyo high school and Larry Crowder will give a presentation about the STRETCH project to a group of Japanese students.

Below is a little description about the Koyo High School:

　Thank you for visiting the Koyo High School website.

　Our school was established in 1948 when Nagoya Municipal Commercial High School and Nagoya Municipal Second High School were merged to become Nagoya Municipal Koyo High School.

　In 2006, the school was designated a "Super Science High School" by the Ministry of Education, Culture, Sports, Science and Technology, and has since been working on research aimed at improving science and mathematics education. Furthermore, in 2015, the "International Science Department" was established as the first science and mathematics department in Aichi Prefecture, with the goals of "nurturing global human resources who can compete on the world stage" and "advancing to top science and mathematics universities," and the school now plays a leading role in promoting science and mathematics education in the prefecture.

　In recent years, the school has also been placing emphasis on inquiry-based learning, and every March students present the results of their research conducted during comprehensive inquiry time to an external audience.

　Club activities are also very popular, with many participating in national and prefectural tournaments every year, making this a school that excels in both academics and sports.

　Going forward, all of our teaching staff will continue to work together to encourage each and every student to have a warm and compassionate heart, an inquisitive mind that can discern the truth, and to grow up healthy and strong both physically and mentally. We will continue to provide educational activities that are even more satisfying than before, and strive to gain the support of many of you.

　We appreciate your continued support.

Naotaka Akita, Principal of Nagoya Municipal Koyo High School　

6/20/2024

We made our way to PNPA once again this morning (4th day) to attach 6 more tags. We were able to complete the attachments at 1300 hours for all 28 juvenile loggerheads in Cohort II. At the end of the day today the STRETCH team and all of the wonderful PNPA personnel gathered together to celebrate the end of the attachment process... BUT, this is just the beginning. These 28 juvenile turtles are destined to be released in the North eastern central Pacific ocean sometime around 7/9/2024. After their release, if all goes well, we will start getting location data for all of them and track their movements over the next 10-14 months.. Our hope is for the tags to last over one year!

The STRETCH team with 4 of the last 6 juvenile loggerheads that we completed today.

Juvenile loggerhead turtles that have been recently equipped with wildlife computer satellite tags are fed by aquarium staff. These juveniles are part of the 28 turtles that represent Cohort II of the STRETCH Project.

6/19/2024

Seven more satellite tags were attached to juvenile loggerheads today. We have 6 more to go tomorrow and we will have completed 28 turtles. Twenty five of the turtles are carrying Spot 6 tags which give location only and three of the turtles are carrying Splash10 297 tags which will transmit temperature and diving data which will help us to analyze the behavior of these three turtles that will help to explain/correlate their movement to their diving and feeding behavior.

The final group of 6 turtles will get their tags tomorrow!

6/18/2024

The STRETCH team has been working for the last two days at PNPA attaching satellite tags to 15 juvenile loggerhead turtles that are part of Cohort II. We have 13 more tags to attach and will complete that task over the next two days. Below is a short video of the process of attaching the tags onto the turtles that will be released into the northeast central Pacific ocean sometime around Jule 9, 2024. Please see the Loggerhead STRETCH web site for further information.

6/16/2024

We made it to Kanayama Nagoya at 1400 h and left our bags at the Crown Plaza Hotel before catching the metro to the aquarium to check in on the turtles. Masanori Mori met us and showed us the 28 stretch turtles he has been raising for 2 years. We were also able to see Cohort III turtles that are about 11 months old right now. The turtles all look very good and ready to start their next journey into the Pacific Ocean.

Below are some pictures of the turtles and some of the stretch team members.

Team members Jack, Laura and George join Mori-san in checking out Cohort II STRETCH turtles.

While we were with the turtles they were fed a delicious meal of fish and squid.

Laura Jim poses with some of Cohort III turtles (11 months old)

Head turtle curator, Masanori Mori.

Hungry Cohort III turtle

6/14/2024

We have begun our second trip to Nagoya to attach 25 Spot 6 satellite tags and 3 Splash10 tags to the juvenile loggerhead turtles that were hatched in Koichi, Japan and raised at PNPA. We will be starting the work on Monday, 6/17/24 at the aquarium. We are planning on attching 7 tags per day for 4 days. The turtles will then be kept in individual baskets in sea water to protect the sat tag antennas.

The MOL ship we are using to transport the turtles to the central north east Pacific is named the "Firmament Ace". You can follow the progress of the ship HERE . The ship will arrive in Nagoya Ko on 6/26 and the turtles will be loaded on the ship on 6/27. Subsequently the ship will go to Yokohama to complete cargo loading and then will depart for Panama. It is estimated that the ship will reach the release area on July 9th.

Because the turtles will not be release for several weeks after the tags are attached, we program the tags to be in standby mode of nearly three weeks before they begin transmitting locations (they use very little energy when in standby mode.

In addition, we are reducing the number of days the tags transmit locations to every other day in an effort to extend the battery life of the tags. IN THEORY, by reducing the frequency of transmission by 2, we should increase the number of days that the tag can transmit by 2... That is what we are hoping for!

Example of a Wildlife computers Spot 6 tag.

We will also put out 3 Splash10 387 tags

Splash10 297s tag that we will place on three of the turtles. These tags will give us temperature, depth data for each of the turtles which will help us to better understand the daily behavior of these individuals.

__________________________________________

The stretch team is about to reassemble in Nagoya Japan at the Port of Nagoya Public Aquarium where Masanori Mori has been raising our second corhort of juvenile loggerhead turtles for release in the northeast central Pacific Ocean.

This year's satellite tag attachment team is composed of:

Larry Crowder -STRETCH PI

George Balazs - STRETCH PI

Dana Briscoe - STRETCH PI

Laura Jim - STRETCH team member

Marc Rice - STRETCH team member

Catherine Lee Hing - Shipboard assistant for deployment of turtles

Jack, Sabine, Charlotte - HPA Student Volunteers

Masanori Mori (PNPA turtle curator) has been raising 30 juvenile loggerheads for the past 2 years and they are now of a size where they can easily carry a satellite tag. We will travel to PNPA on June 16 to carry out the attachment of the tags and prepare the turtles for their release in the northeast central Pacific ocean in early July. For information on the outcomes of the first cohort release please visit our website and/or our blog.

We have been informed that Cohort II will be transported onboard the MOL ship "Firmament Ace." She is the same size and configuration as last years ship, "Galaxy Ace."