Aquaculture food bb

Land & sea We use the same “feedlot” system on marine life such as carp, catfish, and tilapia

It is known as “aquaculture”

Aquaculture history • Carp were farmed in China in 2500 BC (1st country to farm fish) • Wen Fang – 1st fish farmer • England – 1500 AD carp culture • US – 1st fish hatchery in Oregon 1877 & Ohio trout farm in 1853 • 1930s -­‐ FDR’s Farm Pond Program

Aquaculture is the fastest growing sector of US agriculture Accounts for 25% of all seafood consumed in the US

Aquaculture & Marine resources • Fish & Shellfish give us a valuable source of food protein & livelihood for many in the seafood industry

Marine resources

• Most fisheries close to coasts that have been impacted by human acLviLes have been overfished • This is a major problem worldwide • Since over 15% of all animal protein comes from seafood, the industry always has a demanding market • Now, technology is used to increase yield, which has led to overfishing

bycatch

• When nontarget fish species other marine animals are caught in nets or through other fishing methods, they are called bycatch

• Fishing methods such as boGom trawling, gill neJng, & longlining are esp. subject to bycatch • For every 1lb. of shrimp caught, 9lbs. of nontarget species are thrown away

Bottom trawling

Gill netting

longlining

aquaculture • In order to fish more sustainably & prevent further overfishing, aquaculture has become very popular • Growing marine or aquaLc species in net pens or tanks is known as aquaculture

aquaculture pros: • Aquaculture provides economic benefits & food security, relieves pressures on wild fish stocks, & can be sustainable

Cons: • Aquaculture also gives rise to polluLon, habitat loss, & other environmental impacts

Aka “blue revolution”

“fish farms” • World fish populaLons are plummeOng

• Technology & increase demand • Aquaculture involves raising aquaLc organisms in a controlled environment • Species are raised in open-­‐water pens or land-­‐based ponds • Why is it becoming so popular? Increased seafood consumpLon; good quality of protein low in fat; beYer producLon to cost raLo

“fish farms” & $$$

Growing rapidly • Over 220 freshwater & marine species are grown using aquaculture • It is the fastest-­‐ growing type of food producLon • Provides ¾ of the world’s fish & ½ of the shellfish • Most widespread in Asia

Types of aquaculture • Food fish: Ca\ish, Tilapia, Rainbow trout, shrimp, striped bass, etc.

• BaiVish: fathead minnows, goldfish, crawfish, etc.

• Sport fish: Largemouth bass, bluegill, trout, channel ca\ish

Types of aquaculture • Extensive Aquaculture: Minimal control, lower density, ponds, 3rd world • Intensive Aquaculture: Highly controlled, high density, confined, industrialized

Production methods • Ponds, cages & pens, raceways, closed re-­‐ use systems

Polyculture aquaculture • Raising different species together (polyculture) reduces many problems caused by raising one type (monoculture) • Polyculture yields 50% higher than monoculture aquaculture farming • Example? Raising grass carp (eats plants) & silver carp (filter feeder of smaller organisms)

Aquaculture conculsion benefits:

drawbacks:

• A reliable protein source • Can be sustainable • Reduces pressure on overharvested wild fish • Energy efficient

• Diseases require expensive anLbioLcs • Lots of waste • Uses grain • Escaped GM fish introduce disease/ outcompete wild fish

• When nontarget fish species other marine animals are caught in nets, they are called ___________ BYCATCH • The culLvaLon of a variety crops in a single space is called _POLYCUL _____________ T URE • The fastest growing type of food producLon is _______________ AQUACULT URE

• Fishing methods such as boGom trawling, gill neJng, & longlining are esp. subject to bycatch

• Purse-­‐seining involves segng a large circular ‘wall’ of net around fish, then ‘pursing’ the boYom together to capture them

• A seine is fishing net that hangs verLcally in the water with floats @ the top and weights @ the boYom edge, the ends being drawn together to encircle the fish

• Globally, fish stocks are decreasing from overfishing • Ecologists encourage naLons to protect at least 20% of coastal shore territories as marine refuges • Coral reefs are especially @ risk • ScienLsts report 90% of all reefs are threatened by: • Sea temperature change • Coral mining • Sediment runoff • Ocean dumping • DestrucLve fishing methods

• Likely negaOve environmental impacts of the loss of coral reefs include: • EliminaLon of food source for marine life • Loss of breeding grounds • Loss of shelter/hiding places • ExLncLon or decrease in populaLons • Loss of biodiversity • DestrucLon of coastal habitats • Accelerated erosion of shoreline habitat

• With current trends, researchers predict living coral reefs will be gone by 2060

• When plants & animals found in one part of the world are transported to a far distant locaLon, they are known as nonnaOve or alien species • We’ve talked about this before, esp. with Cane Toads -­‐-­‐-­‐ however, it can also be an issue in our oceans • When ships travel from one area of the world to another, they carry alien species with them in their ballast water

• Currently, there are over 200 different nonnaOve species living in San Francisco Bay, California • The bay’s natural ecosystem has changed a lot

• Approximately half of the seafood eaten worldwide – including the US – is farm-­‐ raised • Helps reduce the pressure that is placed on fisheries by tradiLonal fishing methods