{"id":2331,"date":"2016-01-08T20:22:38","date_gmt":"2016-01-08T20:22:38","guid":{"rendered":"http:\/\/blog.cwf-fcf.org\/?p=2331"},"modified":"2016-10-07T15:14:39","modified_gmt":"2016-10-07T15:14:39","slug":"why-are-our-turtles-disappearing-from-the-map","status":"publish","type":"post","link":"https:\/\/blog.cwf-fcf.org\/index.php\/en\/why-are-our-turtles-disappearing-from-the-map\/","title":{"rendered":"Why are our turtles disappearing from the map?"},"content":{"rendered":"

\"jan<\/p>\n

I wish we knew!<\/p>\n

Each time we put a transmitter on a sea turtle we know that we\u2019re sending that scientific instrument out into the ocean. And that is something to think about: we\u2019ve sent it somewhere entirely beyond our control.<\/p>\n

We can track things remotely, like the strength of the battery and the movements of the turtles. So I can tell you that the battery on their tags were going strong when the tags themselves stopped transmitting. I can also tell you that Christie, Beverly and Sharon were all behaving much the same as they had previously up until the transmitters stopped working. This is important because if they had been caught in some kind of fishing gear, for example, we might see a change in their behaviour or a change in the amount of time they were at the surface of the water. But it seems as though they were all swimming freely when the tag stopped transmitting.<\/p>\n

 <\/p>\n

What has most likely happened is that the tags \u201cbiofouled.\u201d Biofouling is when organisms like algae and barnacles grow on the tag and prevent it from working properly. The organisms prevent an important switch on the tag from drying. When the switch is dry (which normally happens when the turtle is at the surface of the water), the satellite tag transmits data. If the switch isn\u2019t dry or if it is covered, the data is not transmitted. We think this is the case with our turtles.<\/p>\n

Biofouling is not unusual\u2014it is just frustrating! But, the good news is that we\u2019ve had turtles with biofouled tags start transmitting again after a while (when presumably the organisms colonizing the tag fall or are knocked off). We\u2019ve also had turtles that have tags that stopped working found on the beach anyway\u2014including Christie herself this spring (https:\/\/canadaseaturtle.wordpress.com\/2015\/05\/04\/nothing-short-of-amazing\/<\/a>)! And, famously, including Red Rockette during the last Great Canadian Turtle Race (https:\/\/canadaseaturtle.wordpress.com\/2013\/04\/23\/red-rockettes-tag-is-back\/<\/a> ).<\/p>\n

So for the Christie, Beverly and Sharon fans out there\u2026keep the faith. These animals will surprise you.<\/p>\n

Guest Post written by Kathleen Martin, Canadian Sea Turtle Network<\/strong><\/p>\n

 <\/p>\n

———————————————————————————-<\/p>\n

<\/strong><\/p>\n

Pourquoi ne pouvons-nous plus rep\u00e9rer nos tortues? <\/strong><\/p>\n

Si seulement je le savais!<\/p>\n

Chaque fois que nous munissons une tortue luth d\u2019une balise, nous savons que nous jetons un instrument scientifique dans l\u2019oc\u00e9an. Pensez-y-bien : nous avons rel\u00e2ch\u00e9 cet instrument dans un endroit hors de notre contr\u00f4le.<\/p>\n

Nous pouvons suivre certains \u00e9l\u00e9ments \u00e0 distance, comme la charge de la pile et les d\u00e9placements des tortues. Je peux donc confirmer que les piles dans les balises \u00e9taient charg\u00e9es lorsque ces derni\u00e8res ont cess\u00e9 de transmettre de l\u2019information. Je peux aussi vous dire que Christie, Beverly et Sharon se comportaient tout comme avant lorsque les balises ont arr\u00eat\u00e9 de fonctionner. C\u2019est une information importante, car si les tortues \u00e9taient prises dans un engin de p\u00eache quelconque, par exemple, elles auraient pu changer de comportement et passer plus ou moins de temps qu\u2019avant \u00e0 la surface. Mais il semblerait qu\u2019elles nageaient librement quand nous avons perdu la transmission.<\/p>\n

Des salissures marines se sont vraisemblablement fix\u00e9es aux balises. Les salissures marines sont des organismes comme des algues et des morailles qui se d\u00e9veloppent sur les balises et qui emp\u00eachent un important commutateur de s\u00e9cher. Lorsque le commutateur est sec (ce qui est normalement le cas quand la tortue est \u00e0 la surface), la balise transmet des donn\u00e9es. Si le commutateur n\u2019est pas sec ou s\u2019il est recouvert de salissures, les donn\u00e9es ne sont pas transmises. Nous croyons que c\u2019est ce qui s\u2019est produit dans le cas de nos tortues.<\/p>\n

Les salissures marines ne sont pas inhabituelles \u2013 mais elles sont tr\u00e8s contrariantes! Cependant, il est d\u00e9j\u00e0 arriv\u00e9 que des balises avec des salissures marines se remettent \u00e0 transmettre des donn\u00e9es apr\u00e8s un certain temps (sans doute apr\u00e8s que les organismes qui ont colonis\u00e9 la balise soient tomb\u00e9s). Nous avons \u00e9galement retrouv\u00e9 sur la plage des tortues dont les balises ne fonctionnaient plus \u2013 y compris Christie le printemps dernier (https:\/\/canadaseaturtle.wordpress.com\/2015\/05\/04\/nothing-short-of-amazing\/<\/a>) et la c\u00e9l\u00e8bre Red Rockette durant la derni\u00e8re Grande course canadienne des tortues (https:\/\/canadaseaturtle.wordpress.com\/2013\/04\/23\/red-rockettes-tag-is-back\/<\/a> ).<\/p>\n

Donc, si vous \u00eates un admirateur de Christie, de Beverly ou de Sharon, ne perdez pas espoir. Ces tortues peuvent encore nous surprendre!<\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

I wish we knew! Each time we put a transmitter on a sea turtle we know that we\u2019re sending that scientific instrument out into the ocean. And that is something…<\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[636,6],"tags":[134,136,620],"class_list":["post-2331","post","type-post","status-publish","format-standard","hentry","category-coasts-oceans","category-endangered-species","tag-great-canadian-turtle-race","tag-leatherback-sea-turtle","tag-marine-conservation"],"_links":{"self":[{"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/posts\/2331","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/comments?post=2331"}],"version-history":[{"count":2,"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/posts\/2331\/revisions"}],"predecessor-version":[{"id":2335,"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/posts\/2331\/revisions\/2335"}],"wp:attachment":[{"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/media?parent=2331"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/categories?post=2331"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.cwf-fcf.org\/index.php\/wp-json\/wp\/v2\/tags?post=2331"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}