Marine Resources Flashcards
what percentage of food do humans consume from the sea?
16-38%
- regional and temporal variance
how much of the protein diet in island communities?
98% (FAO)
what is MSY?
- maximum sustainable yield
-> max biomass that can be removed from standing stock yearly and still retains a viable fishery - regional stocks are monitored separately
- used to sustain the populations
what is standing stock?
- specified amount of organisms in system at any one time
- successful fisheries leave enough individuals from standing stock to repopulate ecosystem
what causes variation in standing stock?
- recruitment - reproduction
- survival
- nutrients - resources
- location - spatially constrained or one area becomes disturbed
what is the allee effect?
- depensation
- too few adults to produce sufficient recruitment to sustain pop
- occurs in small pop
what are the methods for sustainable marine mammal fisheries?
- potential biological removal
- risk based approach
is this PBR or risk based approach?
- max number of animals that may be removed from marine mammal stock while allowing stock to reach or maintain its optimum sustainable population
what is the optimum sustainable population?
the number of animals that’ll result in max productivity
is this PBR or risk based approach?
- model assessment that estimates the risk of population decline under various harvest scenarios
goal is 5% risk of decline - precautionary risk
what are the two types of fisheries?
long lines and drift-net fisheries
how do long lines catch fish?
there is a net that trails behind boats and are weighed down
what are drift nets?
- suspended nets in the water column
- floaters on the top
- weights on the bottom
where are fisheries found?
off shore
what happened in 1991 for reduction efforts?
moratorium on driftnet fishing
what happened in 1996?
take reduction team - NOAA
- recover and prevent marine mammal depletyion
-> focused on the relative strengths and limitation of different weak rope configurations
-> focused on relacing existing ropes with sleeves, spliced or tapered line, toppers and/or line capped at 1700 lb breaking strength as alternative ways to minimize likelihood of serious injury or mortality to right whales entangled in line
-> decrease bycatch using ropes
what is the purpose of the Pacific Leatherback Conservation Area?
- fisheries are active during the summer months and so they closed close the area off to stop bycatch from occurring
what is trawling?
- ploughing the deep sea floor -> offset balance
- uses a big net to catch benthic organisms
what are the two effects of trawling?
- flattening of habitat - reduces heterogeneity
- increase of suspended sediment
what are compensation catches?
blue marlin decreases then sailfish increases but then decreases and so swordfish increases and is the new target bc of compensation catches
which province is the larger grower of salmon?
BC
- enclosed in pens and there is no natural repro and nutrients are pumped
what are the challenges on aquaculture?
- feed source - sustainable food sources
- waste - lots of fish in one area causing algae bloom
- antibiotics/chemicals - reduce algae growth
- sea lice transfer to wild populations
what are the sea animals found in aquaculture?
- bivalves
- shrimp
- algae
what is a problem with shrimp in aquaculture?
grow out ponds can be destructive to habitats
what are the uses of algae?
- food
- nutritional supplements
- algin-emulsifier
- food stabilizer
what are two renewable energy resources?
wind
ocean currents - Aquanator (Aus)
wave energy - LIMPET (scotland)
tidal energy
what are the challenges with wind energy?
- wildlife migration routes
- remote locations for grid access
- noise/aesthetics
what is the major resource that provides majority of the economic value of marine resources?
95%
- oceanic sources - major new sources
what is another non-renewable energy resources?
- methane
- huge
- found in substrate that is stable at high pressure and low temp
where is the oil in oceans found?
natural seeps
- 45-46%
how was oil introduced to the oceans?
- humans
- oil spills, leaks, storm drainage
- contributes to massive oil pollution
- effects are immediate and long-term
- type of oil into not reg system
- rate of oil into system is fast
what are the long-term impacts of oil spills?
abnormal development and mutations
- PAH - polycyclic aromatic hydrocarbons
-> derivative of fossil fuel
- hydrophobic
- attach to sediment
- induce cancers
what does stress responses do to the environment?
- oil spill on Galapagos affects marine iguanas of another island
- corticosteroids increased iguana pop after spill
- after high sea surface temp anomalies
- iguana pop decline - starved
- small amounts of oil destroy the gut bacterial fauana
what does mining produce in terms of non-renewable resources?
- phosphate fertilizer
- manganese nodules - alloys
- metal sulfides - metals
- copper
what is deep sea mining regulated by?
international seabed authority
what occurred in Naru?
they requested to deep sea mine but they have to be registered to do that so they requested ISA to create regulations but they did not
- exploited resources so needed to deep sea dive to sustain economy
what are marine natural products?
- salt and marine invertebrates
-> rich source of novel chemical compounds
-> harvest invertebrates - isolate compounds - test effectiveness as (anti-viral agents, anti-cancer, anti-malarial, anti-inflammatories)
what did Gertrude Elion do?
- nobel prize for making acyclovir - purine derived from marine sponge
