Population Dynamics and Ecology Concepts

The video discusses the impact of cold weather on bird populations at Cavenham Heath National Nature Reserve. It highlights how frost affects waterbirds and small birds, leading to population crashes. The concept of density dependence is explained, showing how populations recover over time. Key aspects of population ecology, including the effects of external factors like weather, are also covered.

What is the main reason the wetland at Cavenham Heath is devoid of waterbirds?

• The wetland is too shallow.

• The wetland is too crowded.

• The wetland is frozen.

• There is a lack of food.

Which bird populations are most affected by prolonged cold weather?

• Owls and nightjars

• Eagles and hawks

• Pigeons and doves

• Kingfishers and herons

Why do small birds struggle in cold weather?

• They have a large body size

• They lose a lot of heat

• They are not affected by cold

• They have a small surface area

What happened to the wren population during the 1962/63 winter?

• It doubled

• It crashed by 80%

• It remained stable

• It increased by 80%

What is density dependence in ecology?

• A process where population size is irrelevant

• A process where population size affects breeding and survival

• A process where external factors have no impact

• A process where populations never recover

How does density dependence help populations recover after a crash?

• By increasing competition for food

• By reducing breeding output

• By increasing survival and breeding output

• By eliminating territoriality

What happens to breeding output when population density is high?

• It decreases

• It increases

• It remains the same

• It becomes unpredictable

What are the three components that affect population dynamics?

• High population growth, competition, climate change

• Territoriality, food scarcity, migration

• Low population growth, density dependence, external factors

• Predation, disease, habitat loss

What role do external factors play in population ecology?

• They have no effect on populations

• They stabilize populations at equilibrium

• They only affect small populations

• They push populations away from equilibrium