4.3 Consumption of organisms from freshwater and marine ecosystems

aquatic ecosystems

ecosystems located in bodies of water including oceans, rivers lakes and wetlands

factors contributing to increased demand for aquatic foods

• rising incomes

• health benefits awareness

• rising population

• urbanisation

aquaculture

the cultivation of aquatic organisms such as fish, shellfish and seaweed in controlled environments

main sustainability challenges facing Roku aquaculture

• overfishing

• habitat degradation

• water pollution

• disease outbreaks

• climate change - causes water temperature to rise and ocean acidification affects the growth

aquaculture economic importance

• give jobs

• generates billions

unsustainable finishing practices

1. bottom trawling

2. ghost fishing

3. use of poison and explosives

bottom trawling

large net is dragged across ocean floor to capture fish and other marine life, it takes everything in its path

=> highly destructive

ghost fishing

Phenomenon where cost of discarded fishing gear continues to catch and kill marine life

use of poison and explosives

damages ecosystems, threatening biodiversity and the livelihoods pf communities dependent on fishing

Solutions for sustainable fisheries

• policy and legislation

• consumer choices

• technological innovation

• community investment

evidence of increasing demand for aquatic

• expansion of aquatic and commercial fishing reflects the growing demand, but it also raises concerns about sustainability and environmental impact

challenges of meeting increasing demand

1. overfishing

2. environmental impact - exposing aquaculture can cause water pollution, habitat destruction and reliance on wild fish for feed

3. supply chain constraints: climate change, marine pollution etc..

why is bottom trawling unsustainable ?

1. flattens coral reefs, sponges and other structures that are essential habitats

2. catches non targeted species, often discards them and leaves to die

3. disrupts food webs, reducing biodiversity and ocean resilience to environmental changes

why is Ghost fishing unsustainable ?

1. entangles coral reefs, habitats

2. traps continue to catch fish

3. reduces fish stock availability for harvest

Why are poisons and explosives unsuitable ?

1. widespread destruction - coral reefs other habitats, non target species

2. human health risks - contaminates seafood

3. slow recovery - coral reefs

→ short-term gain, long-term losses

Broader impacts of unsuitable fishing

1. declining fish stocks - overfishing

2. ecosystem imbalance - removed key species disrupt food web

3. economic and social consequences - for coastal communities that relay on fishing food

solutions for sustainable fisheries

1. policy and legislation

2. consumer choices

3. technological innovation (biodegradable nets - reduce ghost fishing, bycatch)

4. community involvement

Consequences of industrial fishing rise

• factory trawlers

• unregulated fishing

• technological advances

why recovery is hard ?

• ecosystem change

• bycatch

• predator and competition