Fishing/Fisheries Flashcards
Stock Size
A function of population size, spatial variability, and the amount of fishing (fishing effort), which includes the number of boats, fishing hours, and gear quality
Stock Health
Can be determined from its growth in the previous year and recruitment into production
Stock-Recruitment Models
Attempt to predict change in the stock as a function of the stock size in previous years // a popular model predicts that stock increase rate will decline as the stock size becomes large, due to resource limitation
Catch of Finfish
Caught by hooking fishes individually, entangling them in nets, or catching them in nets or traps
Bycatch
An unintended form of catches, and is a major source of fish, sea turtle, and mammal mortality
Maximum Sustainable Yield Model
Fishing may actually increase productivity by reducing the effects of high fish density on reproduction and growth
Consequences of Fishing for Top Carnivores
This has severely reduced populations at the apex of the food chains and increased abundance at lower trophic levels
Stock Reduction
Results from random variation and environmental change, where overfishing accelerates the decline
Most Vulnerable Stocks
Those characterized by long generation times, small clutches of eggs, and fewer spawnings
Exclusive Economic Zones
Extend 200 miles from the coast, and allow for local overfishing
Tools for Sustainable Fisheries
Temporary closure, transferable quotas, fishing limits, ecosystem-based management, and marine protected areas
Whaling Technologies
Extended to the open-ocean around the turn of the 20th century with developments like cannon-powered harpoons, factory ships, and stern slipways
Mariculture
Natural habitats are simulated or enhanced to make the harvesting of food fish more convenient or to increase yields // especially common for mollusks
Fish Farming
A major means of rearing finfishes such as salmon, but may produce fish with undesirable traits and spread of parasites
Variables of Fishery Management
Understanding the life history of the species, the size of stock, physical variables, spawning and feeding grounds, migration routes, etc.
Active Fishing Gears
Usually towed across the seabed or used to encircle fish (e.g. trawl and beam trawl nets, seine nets), also dredges (for shellfish) and gear like spears or harpoons
Passive Fishing Gears
Put in the water and fish are caught when they move into the gear (e.g. nets set in the seabed or left floating in the open), or baited pots and fish traps
Tolerance to Fishing Mortality
Hurt by slow growth, late maturity, and large body size
Trawling
Has less of an impact on sandy seabeds in shallow, tide-swept, wave-impacted areas // Has much more of an impact in deep areas, where wave and tidal action are low, and the seabed is dominated by habitat-forming species
Essential Fish Habitat (EFH)
Defined within legislation as those waters and substratum necessary to fish for spawning, breeding, feeding, or growth to maturity
Fishing Destruction on Reefs
Muro-ami drive netting, bottom set gill nets, heavy traps // all lead to habitat destruction
Ecosystem Approach to Fisheries Management
Requires that the needs of future generations are not compromised by the actions of people today
Which dolphin species were harmed by the tuna catch in the eastern tropical Pacific Ocean?
The coastal spotted dolphin, the eastern spinner dolphin, and the northeastern offshore spotted dolphin
Backdown
A method developed by fishers to release dolphins from the pursed net
