the gold rush caused a rapid increase in the population after 1851.
The higher population size would also decrease. If the first level population decreased, the higher levels would have less to eat. This would cause the weaker organisms in the higher population group to die.
The population could be reduced where the migrants are moving from.
Increase: Survival and Immigration Decrease: Death and Emigration
Temperature
increase in population size
Birthrate > Death Rate
An increase in the availability of food, a decrease in predation pressure, or an improvement in reproductive success are factors that can lead to an increase in the size of an animal population.
Population change refers to any increase or decrease in the size of a population, whereas population growth specifically refers to the overall increase in the population size over a given period, often expressed as a percentage. Population change can be influenced by factors such as births, deaths, immigration, and emigration, while population growth focuses on the net increase in population size resulting from these factors.
The size of the host population can control the spread and prevalence of diseases. In a larger host population, there may be more individuals for a disease to spread to, potentially leading to faster transmission. Conversely, in a smaller host population, diseases may not spread as easily and could be contained more easily.
limiting factors
More trees will increase the habitat of birds, so bird numbers will rise.
take care of the orange tree than the plant could increase its size.