Today's anthropogenic world means that an innocent hermit crab is not only responsible for its own survival, but also has to deal with the dangers of predators.
These scavengers might end up with a lack of nutrition and plastics rather than a satisfying meal after exerting effort and energy in order to smell the delicious decaying prawns or mussels.
Researchers at the University of Hull have discovered that plastic pollution can cause poisonous effects in mussels and hermit crabs.
"Oleamide bears a striking resemblance with oleic Acid, which is a chemical that arthropods release during decomposition. Paula Schirmacher, a chemical ecologist, explained that hermit crabs can mistakenly identify oleamide in their food sources, creating a trap.
"Our study has shown that oleamide attracts hermits crabs." Low concentrations of oleamide lead to significant increases in respiration rates.
Oleamide is a common additive that plastics use as a slip agent and a lubricant to help plastics be removed from molds after they have been shaped. It is also used to smoothen the internal structure of plastics like polypropylene and in many food containers.
It is also an organic molecule found in animal pheromones and human blood plasma. Oleamide was found in cleaner shrimp (Lysmata Boggessi) to be able to catalyze sexual partner mating through the use of a pheromone bouquet.
Contrary to media reports, oleamide appears to only be responsible for triggering food attraction in hermits crabs. It is not involved in sex.
Schirmacher stated that "hermit crabs exhibit a behavior attraction comparable to their response a feeding stimulant."
The team stated that plastic additives that mimic marine infochemicals could be a problem for hermit crabs as well as the odor associated to food.
Nevertheless, mussels also have plastic-related problems.
DEHP (Di-2 ethylhexylphthalate) is a common additive to PVC and plastic softener. It was found that it interferes with blue mussel (Mytilus specie) reproduction systems.
Despite its biological toxicity, this chemical accounts for almost 40% of the global plasticizer market.
Furthermore, animals react differently to these chemicals and chemical changes caused climate change-induced temperature rises depending on how they sex.
DEHP caused female mussels to lose the ability to express their genes for estrogen-related receptors. However, male mussels seem to have higher levels of these genes at higher temperatures. This increased their out-of season spawning organs.
The researchers stated that the combination stressors DEHP/higher temperature have different effects on male and female mussels and could impact the timing of and success in Mytilus species breeding seasons.
Luana Fiorella, an ecologist, said that it is crucial to understand the molecular mechanisms of plastic additives and their impact on reproductive success.
These experiments involved the experimental exposure of animals to the chemical in question. However, the studies were done within the laboratory. These studies may not have taken into consideration all factors that could be found in the natural environment.
It is alarming that so few chemicals can have such profound effects on the physiology and physiology of these species.
This is even more concerning when you consider the other chemicals that we have also poured into our oceans via plastic pollution.
The World Wildlife Foundation warns us that unless we drastically curb our addiction to plastic, there will be more plastic than fish in the ocean by 2050.
Over half of the world’s single-use plastic is produced by just 20 companies. They have no doubt played a significant political and social role to instill our dependence on their products.
This addiction could be leading to the starvation and sexual frustration of many ocean animals, including our own food sources.
Marine Pollution Bulletin published the research on mussels and hermit crabs.