Evidence of Microplastic Ingestion by American Lobster

Background

Modern plastics can last up to 600 years in the marine environment. As long as they persist, they can impact species of ecological and economic importance, including American lobster.

Although modern lobster traps are designed with side panels that allow lobsters to escape if gear is lost, the panels do not always degrade as quickly as predicted, so trapped lobsters may remain exposed to microplastics in "ghost traps" far longer than anticipated. Lobsters are known to chew on manmade objects when in captivity, so they may gnaw on the vinyl coating of the wire mesh (and objects such as bait bags) when confined in ghost traps.

Objectives

Are adult lobsters that reside in derelict (ghost trap) gear subject to potentially higher exposure and ingestion of microplastics? We will test this in the field.*
Are juvenile lobsters capable of ingesting microplastics due to their propensity to filter-feed? We will test whether microplastics are found in tissues, including gills and midgut, in the laboratory.

*Due to COVID impacts, the first objective could not be completed.

Project Period

2020-2021

Investigators

Jason S. Goldstein, Ph.D.
Ben Gutzler, Ph.D.
Maddie Nash

Results

No microplastics were found in the 10 tissue samples (including gut, gill, and hepatopancreas) processed from 5 lobsters.
Plastic material was found lodged within the gut of one lobster.
Microplastics were found in feces and attached to semi-consumed mussel fragments, providing evidence that some microplastics are being passed and processed by lobsters. (Test lobsters were fed mussel meat injected with plastics prepared to mimic that which would be encountered in natural settings.)

Recommendations

Design a more comprehensive longer-term laboratory-based study that addresses the bioaccumulation of microplastics in lobster tissue and organs.
Conduct a coast-wide survey of lobsters at all life stages to identify and map the presence of microplastics.
Explore in-situ behavioral and physiological consequences of microplastic ingestion by lobsters that include movement and swimming capabilities, weight, respiration, mating, fecundity, and susceptibility to disease.
Utilize inexpensive, novel technologies for DIY microplastic assessments.
Educate end users and concerned citizens as to the potential impacts of microplastics on lobsters.