Fisheries Management Flashcards
How does biodiversity of freshwater and marine ecosystems compare?
It is about equal
Why is biodiversity of freshwater habitats high?
because their geographic isolation creates unique abiotic conditions and unique speciation occurs
How does glaciation influence temperature aquatic ecosystems?
These ecosystems are newer so they have less biodiversity than tropical aquatic ecosystems
Are headwaters or large rivers less diverse and why?
headwaters because they are shallow, small and more prone to dessication and large rivers have more niches
What factors influence fish collection methods?
the habitat sampled, species of interest, and effectiveness of method
What is passive sampling?
Utilizes traps and other tools that do not move and wait for fish to be trapped within them`
What is active sampling?
utilizes motion active participation in collection methods
What are examples of active fish sampling methods?
kick-seines, purse-seines, trawls, snorkling, and electrofishing
How is the number of fish in a sample measured?
the catch per unit of effort (CPUE) calculated by number of fish caught over time (effort)
What is the depletion method of estimating population?
repeatedly sampling the same area and using the decrease in catch per unit of effort (CPUE) to estimate population size
What is the mark-recapture method of population estimates?
mark individuals upon capture release then recapture and compare the mark versus unmarked to find population size
Why is fish length and weight important in fishery management?
Fish experience indeterminate growth which is dependent on the available of food and standard temps
How is the energy status of fish determined?
Its condition affected by food consumption and metabolic costs
What is fish condition useful in studying impacts of?
environmental change, human activity, and annual food availability
What is a creel limit?
the daily limit of a fish species limited by size
