University Of Tasmania
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Mistaken identity? Visual similarities of marine debris to natural prey items of sea turtles

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journal contribution
posted on 2023-05-19, 08:45 authored by Schuyler, QA, Chris Wilcox, Townsend, K, Britta Hardesty, Marshall, NJ

Background: There are two predominant hypotheses as to why animals ingest plastic: 1) they are opportunistic feeders, eating plastic when they encounter it, and 2) they eat plastic because it resembles prey items. To assess which hypothesis is most likely, we created a model sea turtle visual system and used it to analyse debris samples from beach surveys and from necropsied turtles. We investigated colour, contrast, and luminance of the debris items as they would appear to the turtle. We also incorporated measures of texture and translucency to determine which of the two hypotheses is more plausible as a driver of selectivity in green sea turtles.

Results: Turtles preferred more flexible and translucent items to what was available in the environment, lending support to the hypothesis that they prefer debris that resembles prey, particularly jellyfish. They also ate fewer blue items, suggesting that such items may be less conspicuous against the background of open water where they forage.

Conclusions: Using visual modelling we determined the characteristics that drive ingestion of marine debris by sea turtles, from the point of view of the turtles themselves. This technique can be utilized to determine debris preferences of other visual predators, and help to more effectively focus management or remediation actions.


Publication title

BMC Ecology



Article number









Institute for Marine and Antarctic Studies


BioMed Central Ltd

Place of publication

United States

Rights statement

Copyright 2014 Schuyler et al. Licensed under Creative Commons Attribution 4.0 International (CC BY 4.0)

Repository Status

  • Open

Socio-economic Objectives

Marine biodiversity