Overfishing
What is overfishing?
Taking more fish from the ocean than can be naturally replenished.
What are microplastics?
Small plastic particles that contaminate oceans, often coming from degraded larger plastics.
What percentage of Earth’s surface is covered by oceans?
71%
What is bottom trawling?
A fishing method that drags heavy nets along the ocean floor, damaging habitats.
What is sustainable seafood?
Seafood caught in a way that maintains the long-term health of fish populations and ecosystems.
Which fishing industry collapsed in the 1990s due to overfishing?
The cod fishery in Newfoundland.
What is cyanide fishing?
Using cyanide to stun fish, a practice harmful to coral reefs and illegal in many countries.
How does climate change affect ocean temperatures?
Oceans absorb excess heat, leading to rising sea temperatures.
What is dynamite fishing?
Using explosives to kill fish, a practice that destroys coral reefs and marine ecosystems.
How can marine protected areas (MPAs) help preserve ocean ecosystems?
MPAs restrict human activities like fishing, allowing ecosystems to recover and thrive.
What is recruitment overfishing?
The removal of mature, reproducing fish, leaving juveniles to replenish populations.
What is eutrophication?
Excess nutrients in the water lead to overgrowth of algae, which depletes oxygen and harms marine life.
What is ocean acidification?
The process where increased CO2 absorption lowers the pH of ocean water, harming marine organisms like coral reefs.
How does the construction of dams affect marine ecosystems?
It alters water flow, disrupts ecosystems, and can lead to habitat destruction downstream.
What is the role of bony fish in the carbon cycle?
Bony fish excrete calcium carbonate, helping to regulate ocean acidity and contributing to the carbon cycle.
What is bycatch?
The capture of unintended species during commercial fishing.
How does thermal pollution affect the ocean?
Warmer water holds less oxygen, which can harm marine organism.
How does rising sea temperature affect fish migration?
Fish species, like tiger sharks, are shifting their migration patterns as ocean temperatures rise.
How do invasive species introduced by humans harm ocean habitats?
They outcompete native species, leading to ecosystem imbalances and biodiversity loss.
What technology can reduce bycatch in commercial fishing?
Turtle excluder devices and more selective fishing gear help reduce unintended catch.
Name one type of indiscriminate fishing that harms ecosystems.
Long lining or bottom trawling.
What impact does plastic debris have on marine ecosystems?
It can entangle marine animals, be ingested, and introduce toxins into the food chain.
What is the effect of rising sea levels on coastal habitats?
It leads to the destruction of wetlands, coral reefs, and other critical marine habitats.
What is the impact of coral reef destruction on marine biodiversity?
Coral reefs provide habitat for many species, and their destruction leads to significant biodiversity loss.
What is desalination, and how does it help address water shortages?
Desalination is the process of removing salt from seawater to produce fresh water, useful in areas with water scarcity.