Human-generated waste is everywhere, including in the oceans. Seeing that many octopuses use trash as their shelter, shows how badly our trash is polluting the oceans.
A systematic review of underwater photos and videos from around the world has counted 24 species of cephalopods that make marine debris their home.
For years, divers and scientists have observed octopuses laying eggs in plastic or fishing gear left in the ocean. Some of these creatures have even been found using glass bottles, ceramic pots, metal pipes, rusty cans, or plastic cups as roofs to protect their bodies.
Quoted from Science Alert, Wednesday (16/3/2022) the researchers noted a number of areas where tourists collect too many sea shells. Cephalopods of different ages have been forced to adapt or perish.
Marine debris is their alternative as a means of protection, but this is actually a worrisome condition. Researchers worry about what will happen if these creatures become too dependent on human waste for shelter.
"The apparent positive effects can also have some adverse and indirect consequences," said the study researchers led by marine biologists from the Federal University of Rio Grande in Brazil.
Some litter, for example, can expose octopuses to toxic chemicals or heavy metals. One of the photos collected, for example, shows an octopus attached to a badly damaged battery. Of course this waste is categorized as 'highly polluting'. Not only octopuses, other sea creatures can also be injured by sharp debris.
In all, the study's authors collected 261 underwater images and videos of octopuses interacting with marine waste. Most of the photos and videos are collected on social media with permission from the original authors, but some are also contributed by marine scientists and research institutes.
The researchers found records of octopus interactions with marine debris have increased in recent years, with most records occurring between 2018 and 2021. That could be because underwater photos are easier to take now than ever. However, this could also be a sign that the marine debris problem is getting worse.
"Despite this description, few studies have focused on the interactions between octopuses and marine debris, and scientific information on this subject has hardly been updated over the past few decades," the authors said.
More research is needed, but this initial review has revealed some important results. The authors initially suspected plastic to be the most common litter used by octopuses. Whereas, in reality, more than 40% of octopus interactions are with glass bottles, and this is mostly used for shelter.
Glass is much harder to break, but it's also easier to sink, which can make it more attractive to seafloor creatures. Plus, the glass also makes it harder for hungry predators to enter and prey.
From the images obtained, the researchers also concluded that clam shells are becoming so rare and human waste dominates that octopuses use them.