ocn331 Mai ke kai, mai ke ola

“It has been estimated that 4.8 to 12.7 million metric tons of plastic waste entered the ocean in 2010 from 192 coastal countries.”

LARVAL FISHES PREFER TO EAT TOXIC MICROPLASTIC, RATHER THAN PLANKTON.

Microplastics - are small plastic particles in the environment that are generally smaller than 1 mm (0.039 in) down to the micrometer range and have been found in all seas.

Today there is increasing concern that the accumulation of microplastic waste particles could affect the functioning of marine ecosystems, but our knowledge of the impacts of microplastic fragments on marine animals is limited. For the first time, scientists have now been able to show that development of fish is threatened by microplastic pollution.  

Under lab conditions, fish reared in different concentrations of microplastic particles have reduced hatching rates and display abnormal behaviors. The microplastic particle levels tested in the current study are similar to what is found in many coastal habitats in Sweden and elsewhere in the world today.

Larval perch exposed to environmentally relevant concentrations of microplastic polystyrene particles displayed stunted growth rates. The authors found that this was related to larval feeding preferences as perch that had access to microplastic particles only ate plastic and ignored their natural food source of free-swimming zooplankton. When are larvae, prefer to eat dangerous microplastics rather than plankton,   According to the study, this is the first time an animal has been found to preferentially feed on plastic particles and is cause for concern. For the first time, scientists have demonstrated that fish exposed to such materials during their development show stunted growth and increased mortality rates, as well as changed behaviour that could endanger their survival.

Some young fish have been found to prefer tiny particles of plastic to their natural food sources, effectively starving them before they can reproduce. 

The lack of an antipredator response made larvae more vulnerable to predators. Indeed, when perch were placed together with a natural predator (pike), fish that had been exposed to microplastic particles were caught and eaten more than four times quicker than control fish, with all fish exposed to microplastic particles dead within 48 hours.  

If this response in fish larvae translates to higher mortality rates as a result of increased predation risk in nature, there could be direct consequences for the replenishment and the sustainability of fish populations.

Photo:  Larval perch from the Baltic Sea with ingested microplastic particles visible in its digestive tract.

“Science,” my ass.