Sea Turtles of Okinawa

(English) How do plastic get stuck in sea turtle nostrils?

By jhjanicki on ������,11�� 16th, 2016 in 環境意識, 生物学, 環境保護, 海上漂流物, コメントはまだありません

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There has been two recent events related to objects stuck in the nostrils of sea turtles which are the product of accumulating plastic debris in the ocean, specifically in the waters of northwest Costa Rica.
One is where a straw was stuck in the nostril of an Olive Ridley sea turtle (Robinson & Figgener 2015) and the other is a plastic fork stuck in the nostril of the same species (Robinson et al 2016).

Image from Robinson & Figgener 2015

Image from Robinson & Figgener 2015

Image from Wyneken 2001

Straw
– Situation –
During the tagging process, the researchers noticed that there is a cylindrical object stuck in the turtle’s left nostril. They used a pair of pliers from a Swiss army knife to gently pulled on the object, and once they realized that it was a straw, the pulled it a couple more times and the entire straw (about 10cm) was extracted. Judging by the stained coloration of the straw and its general state of degradation, the researchers predict that the straw may have been in the turtle for at least a few weeks. Furthermore, the effort required to remove the straw suggests that scar tissue had begun to form around the base of the straw.

– How did it get stuck? –
The researchers believe that instead of the straw being driven into the sea turtles nose from the outside, it was initially ingested orally but was later regurgitated. The passageways for food and air are connected in a turtle just like they are in people. When the straw was regurgitated it did not pass out the mouth but passed through the nasal cavity. The nasal cavity in sea turtles is linked directly to the buccal cavity through a long nasopharyngeal duct (Wyneken 2001).

Image from Robinson et al 2016

Image from Robinson et al 2016

Image from Wyneken 2001

Fork
– Situation –
The researchers saw an object protruding from the nostril of a olive ridley sea turtle as they were collecting epibionts from nesting turtles. They firmly gripped on the protruding end of the object with a Swiss Army knife and after a short pull, the object came free from the turtle’s nose and it became clear that the foreign body was a plastic fork.

– How did the fork get stuck? –
The hypothesis is, the turtle first ingested the plastic fork, which could be mistaken for a penaeid shrimp or a crab’s appendage, and tried to regurgitate it. Being rigid, the fork was angled toward the roof of the mouth as it was regurgitated. Instead of passing out of the mouth, the fork was passed into the internal nares, which are found on the roof of the mouth.The width of the fork’s head stopped the fork from being passing completely out of the nasal passage.

Actions
Currently France is the first and only country that has banned single-use plastic utensils. For the people anywhere else, try to not use plastic straws and utensils, instead consider buying your own reusable straws and utensils.

Literature
Robinson & Figgener 2015. Plastic straw found inside the nostril of an olive ridley sea turtle. Marine Turtle Newsletter 147: 5-6.
Robinson et al 2016. Plastic Fork Found Inside the Nostril of an Olive Ridley Sea Turtle. Marine Turtle Newsletter 150: 1-3.
Wyneken 2001. The Anatomy of Sea Turtles. U.S. Department of Commerce NOAA Tech Memo NMFS-SEFSC-470, 172 pp.