Population dynamics and aquaculture | AQA A-Level Environmental Science Revision | Primrose Kitten

Max harvestable individuals without population depletion.

Maximum Sustainable Yield (MSY)

Harvesting above sustainable limits, harming populations.

Overfishing

Study of population changes over time.

Population Dynamics

Total weight/mass of organisms in a population.

Biomass

Population growth from juvenile survival and migration.

Recruitment

Mass gained by an organism per unit time.

Growth Rate

Number of deaths per unit time in a population.

Mortality Rate

Amount of fish harvested by fishing vessels.

Catch Size

Reproductive output measured by larvae/egg concentration.

Breeding Success

Farming of marine species for food production.

Aquaculture

High energy inputs in small areas for productivity.

Intensive Aquaculture

Low energy inputs over larger areas for efficiency.

Extensive Aquaculture

Choosing parents with desirable traits for offspring.

Selective Breeding

Determining population size using biomass instead of counts.

Population Size Estimation

Indicator of breeding success in marine species.

Larvae Concentration

Number of organisms per unit area in aquaculture.

Stocking Density

Non-living environmental factors affecting organisms.

Abiotic Factors

Living components influencing population dynamics.

Biotic Factors

Number of offspring produced per breeding cycle.

Fecundity

Birth rate, death rate, immigration, emigration.

Population Influencing Factors

Difficulties in gathering representative population data.

Data Collection Challenges

Uneven spread of marine organisms across environments.

Marine Species Distribution

Using landed catch data to estimate wild populations.

Catches Analysis

Managing conditions in intensive aquaculture systems.

Environmental Control

Using natural conditions in extensive aquaculture systems.

Natural Habitat Utilization

Risk of population decline due to high mortality.

Vulnerability to Overfishing

Market demand affecting the catch size of species.

Fishing Vessel Demand

Ability to withstand diseases, enhancing survival rates.

Disease Resistance

Speed at which fish reach market size.

Fast Growth Rate

Using hormones to stimulate fish spawning.

Hormonal Induction

Changing fish gender to optimize production.

Sex Alteration

Genetic makeup indicating female fish.

XX Chromosomes

Genetic makeup indicating male fish.

XY Chromosomes

Induces male traits and sperm production in fish.

Testosterone Exposure

Breeding closely related fish, risking genetic diseases.

Inbreeding

Introducing genes from one organism to another.

Gene Transfer

Severity of disease depends on population size.

Density-Dependent Factor

Using organisms to manage pests in aquaculture.

Biological Control

Chemicals used to eliminate pests and diseases.

Pesticides

Removing waste to prevent disease spread.

Tank Cleaning

Barrier to protect fish from predators and competitors.

Netting

Fish that primarily consume plant material.

Herbivorous Fish

Fish that primarily consume other fish.

Carnivorous Fish

Providing food to fish in intensive systems.

Artificial Feeding

Adjusting water temperature for optimal fish growth.

Water Temperature Control

Increasing dissolved oxygen levels in water.

Oxygen Aeration

Manipulating light to enhance fish growth rates.

Artificial Lighting

Flowing water to reduce collisions and promote growth.

Water Circulation

Energy source often used in intensive aquaculture.

Fossil Fuels

Separate tanks for younger fish to prevent disease.

Juvenile Tanks

Removing unwanted fish to protect farmed stock.

Culling