13C Flashcards
Orientation Clicks
low frequency clicks used in echolocation that give an animal a general idea of its surroundings
Discrimination Clicks
high frequency clicks used in echolocation that give an animal a precise picture of a particular object
Signature Whistles
unique sound produced by a dolphin to identify an individual
Melon
oval mass of fatty waxy material in a dolphins head that functions tin directing and focusing the sounds used in echolocation
Renewable Resources
resources that can replenish themselves
Stocks
separate population of fish that is assumed to be reproductively isolated from others in range
Tagging
prosecute for monitoring the distribution and movement of animals in the environment
Landings
catch made by fishing vessels
Fishing Effort
measure of the number of vessels fishing, number of fishers working, number of hours spent fishing
Overfishing
catching fish faster than they can reproduce and replace themselves
Trawl Nets
large nets that are dragged along the sea bottom
EEZ
the area of corn that a coastal nation controls
Surimi
fishery product made from alaskan pollock
Destructive Fishing
best choices, good alternatives, avoid
Incidental catch(byctach)
non commercial animals that are killed during fishing for commercial fishing
trash fish
term used for incidental fishing ?
drift nets
large nets that may stretch for as much as 60 kilometers
tans
individual sections of a drift net
Aquaculture
The use of aqua culture techniques to breed and raise marine organisms
Monoculture
The process of raising a single species in aqua culture
Polyculture
The process of raising several species together in aqua culture
raft culture
A form of aqua culture, in which juveniles of commercially valuable molluscs are attached to robes expended from rafts
Eco-friendly aqua culture
A type of aqua culture where the growing of fish or shellfish, do not have negative impacts on the environment; some positves are
1. Using waste to produce food for animals.
2. using waste as a fertilizer for plants
3. Using animals to minimize waste back to sea.
problems with aquaculture
- Pollution.
- Wild fish caught to feed cultured fish.
- Invasive species.
Tuna
- longlined- yellowfin, bigeye, albacore
- hand lined- bluefin, albacore
- purse seined- yellowfin, bluefin
purse seines
huge nets that can be closed by pulling in a line, similar to the way a purse or a bag of marble is closed
Marine mammal protection act
1972 to reduce e the number of marine mammals including dolphins killed in fisheries
backing down
technique in which the skiff setting the purse seine backs up, causing the edge of the net to drop beneath the surface of the water allowing dolphins to escape
ocean ranching
process in which young fish are raised in one’s and then returned to the sea to supplement natural populations
desalination
process of removing salt from seawater
sulfides
minerals containing sulfur
same and gravel
extract them for:
-cement
-concrete
-replenishing natural beaches
-creating artificial beaches
fossil fuels
fuels formed from the remains of organisms that lived millions of years ago
meghan hydrate
ice that holds methane gas
