Tahiti, French Polynesia 2013 Deployments Status Fish Tagged Reported Days at Large 6 3/28/ /6/ /6/

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1 A total of 12 Wildlife Computers minipat tags were deployed from Kelsey Lee on Pacific blue marlin in French Polynesia between February 21, 2013 and April 16, Each tag was programmed to report 180 days or 240 days post- release. Seven of the 12 tags reported, with five of the tags reaching their full programmed deployment duration (although two of these five were not on marlin the whole time see notes below). The results are summarized in the following table: Tag Deployment Period (days) Tahiti, French Polynesia 2013 Deployments Status Fish Tagged ed Days at Large Distance (nm) Est. Wt. (lbs) 11P UP 1 2/21/ /19/ P UP 2 2/21/2013 8/21/ P UP 3 3/10/2013 9/6/ P Est. Wt. (kg) Angler Chase Calen Durk Jorritsma 4 3/22/ Rob Ford 11P UP 5 3/23/2013 5/21/ P /28/ P UP 7 3/30/ /25/ P P /6/ /6/ P UP 10 4/7/ /23/ P UP 11 4/12/ /10/ P /16/ Steve Walker Drew Bartlett Drew Bartlett Paul Meltzer Jon Stansbury Paul Meltzer Brandon Hunt Tagger Patrick O'Connell Patrick O'Connell Patrick O'Connell Patrick O'Connell Perhaps the most interesting aspect of this dataset is the variability in behavior exhibited by the marlin. Some of the marlin traveled extensively. Specifically, tags 11P0663 and 11P0675 headed northwest and passed the equator into the northern hemisphere. The other marlin remained more localized and spent the entire deployment duration in the vicinity of the Polynesian islands (tags 11P0646, 11P0630, 11P0669, 11P0658). After the 12 tags were deployed, Wildlife Computers informed us that there was a bug in the tag software of the minipat tags which could result in the tag s failure to recognize that it was no longer attached to a living fish. We saw this result with tags 11P0644 and 11P0669, which released from marlin early and then floated at the surface for extended periods of time before reporting. Tag 11P0644 released from the marlin less than a week post deployment, but did not report until the 180 day programed date; tag 11P0669 recorded data on the marlin for about three months before it released from the fish, but waited until the 240 day

2 programmed date to report. Most interestingly, these two tags provided very curious datasets despite their early releases. In the graph of tag 11P0644, you can see that the marlin was diving to depths around 100 meters (m) which abruptly stopped after five days. The tag then floated at the surface but was occasionally grabbed by something and pulled down to depths of almost 800 m. We saw similar occurrences in the data from tag 11P0669, which you can see in the graph was grabbed at the surface and taken down to more than 700 m before being released and floating back to the surface. We guess that this may be the result of a large squid mistaking the tags for food and pulling them down, but that is only speculation. Of the twelve tags that were deployed, five failed to report which is an unusually high percentage. Although there are a variety of factors that can lead to non-reporting tags, we believe that the tagware bug may have contributed to this issue. Under normal circumstances, when a tag releases prematurely, it floats at the surface for just a few days (96 hours, to be exact), before it begins the reporting cycle. However, because of the tagware bug, affected tags may have floated at the surface for weeks or months before reporting, during which time they would have been at risk of extensive biofouling (we have seen tags with barnacle growth on the flexible antenna stalk, which could lead to the antenna being pulled into the water and thus unable to transmit). Fortunately, once the issue was identified by Wildlife Computers, we were notified and all of the remaining minipat tags were updated with new tagware to address the problem. In summary, it is very exciting to see so many long-term datasets from these tags. The two tags that recorded data on marlin for a full 240 day period are also the two tags which made it all the way to the northern hemisphere (tags 11P0663 and 11P0675)! Further, tag 11P0675 recorded a distance of 1,816 nautical miles (nm), which is the fourth longest track recorded in IGMR history, and tag 11P0663 recorded a distance of 1,626 nm, which is the sixth longest track record in IGMR history! This finding lends credence to the possibility that there may be connectivity between the Pacific blue marlin encountered near the Hawaiian Islands and those in the South Pacific. We hope that with longer duration tagging, potentially coupled with population genetics sampling and analysis, we can further explore this possibility.

3 Tag 11P0663 Fish 1 Tag number: 11P0663 Sponsor: Angler: Chase Tagger: Estimated weight: 68 kg Deployed: 2/21/2013 ed: 10/19/2013 Days at large: 240 Distance traveled: 1626 nm Maximum depth: 360 m Minimum temp: 9.2 C Maximum temp: 30.6 C

4 Tag 11P0644 Fish 2 Tag number: 11P0644 Sponsor: Angler: Calen Tagger: Estimated weight: 75 kg Deployed: 2/21/2013 ed: 8/21/2013 Days at large: 181 Distance traveled: 219 nm Maximum depth: 792 (160) m* Minimum temp: 6.0 C Maximum temp: 29.4 C

5 Tag 11P0646 Fish 3 Tag number: 11P0646 Sponsor: Angler: Durk Jorritsma Tagger: Estimated weight: 68 kg Deployed: 3/10/2013 ed: 9/6/2013 Days at large: 180 Distance traveled: 180 nm Maximum depth: 504 m Minimum temp: 8.8 C Maximum temp: 29.8 C

6 Tag 11P0630 Fish 5 Tag number: 11P0630 Sponsor: Angler: Steve Walker Tagger: Estimated weight: 45 kg Deployed: 3/23/2013 ed: 5/21/2013 Days at large: 59 Distance traveled: 336 nm Maximum depth: 320 m Minimum temp: 15.8 C Maximum temp: 30.4 C

7 Tag 11P0669 Fish 7 Tag number: 11P0669 Sponsor: Angler: Drew Bartlett Tagger: Estimated weight: 45 kg Deployed: 3/30/2013 ed: 11/25/2013 Days at large: 240 Distance traveled: 712 nm Maximum depth: 744 (408) m* Minimum temp: 5.4 C Maximum temp: 30.4 C

8 Tag 11P0658 Fish 10 Tag number: 11P0658 Sponsor: Angler: Paul Meltzer Tagger: Patrick O'Connell Estimated weight: 215 kg Deployed: 4/7/2013 ed: 10/23/2013 Days at large: 199 Distance traveled: 16 nm Maximum depth: 504 m Minimum temp: 7.8 C Maximum temp: 29.4 C

9 Tag 11P0675 Fish 11 Tag number: 11P0675 Sponsor: Angler: Tagger: Patrick O'Connell Estimated weight: 54 kg Deployed: 4/12/2013 ed: 12/10/2013 Days at large: 242 Distance traveled: 1816 nm Maximum depth: 416 m Minimum temp: 9.0 C Maximum temp: 30.6 C