GEOG 2500 Lecture 4: Plastics In Ocean Notes
28 May 2023
School
Department
Course
Professor
Pacific Garbage Patch
Plastic in the ocean
Microplastics
- Breakdown of larger plastics
- Made to be small
Microbeads from facial soap goes down the drain and into the water and looks like
phytoplankton to the ocean animals
Microbeads come from cosmetics and toothpaste
Beatthemicrobead.org
Mercury contamination
- Bioaccumulation or biomagnification
- Accumulates as it makes it way up the food web
- Mercury is a neurotoxin
Overfishing
Bycatch
- From a shrimp trawl
- Was often 85% of total catch
- Not the target species
Fishing methods
- Trawl- drags behind a ship with a net to gather adult fish, small fish can escape because
of the holes
- Purse seine- circular net, wall of netting. Drives around in a circle to catch. To capture
schooling fish, tuna
- Longline
- Gillnet- and drift nets, catch everything, even mammals, can be disconnected
accidentally. Problem w/ mammals caught in nets, walls of netting to tangle fish
What can be done?
- Close fishing areas, ban gear, eat fish that are sustainably harvested (consumer action)
- Fishing farming
- Potential solutions to overfishing
- Has its drawbacks:
- Disease
- Mixing wild and farmed populations
- Added chemicals
