Question

ge ed out of estion Finisht In Kenya, the Shelorick Elephant orphanage takes care of elephants that have lost their herd as a result of poaching. In 2012, the orphanage had a population size of 387 elephants. Over the next two years, they had 18 pregnant cows birth successfully. Three cows were lost due to complications with their pregnancies. They lost 14 more from sickness. They found 57 elephants that required care and were able to release 12 into the wild. All of the elephants are kept in a 225 m * 175 m rectangular park Calculate the following for this population (5 mars 1. Population growth 2. Growth rate 3. Per capita growth rate 4. Population density at I beginning of the year IL end of 2 years Express your answers using two significant digits (hp с 96 A 5 H 6 7 8 ?

Answer 1

- -ОАN es : — Beginning of the year population Size = 387 elephanta end of two year population Size = 387 $-12 = 375 elephants 1- population goowth = negative growth of 12 elephants in two yearson 2- Growth rate= (Perca n+Х) 35 - 287 3 87 Хоо C -3:1). growth rate – 2: 2. 3- Pes Capi» «Coth o14 = - -1Ssy. Number of years 4 - population density at (2 bе. Б. } o*9 8 of the year Number of populañon Land area (in S9 km) 387 0-22ҫ киx o'ѕ «у) 387 О: 03935 S9 K2 - 982g •57 /s9 к» 2) " end of 2 year 375 о. 03 93% S9") з 9X23 • go/s9. Kry, CS Scanned with CamScanner

Population regulation is a density-dependent process, meaning that population growth rates are regulated by the density of a population.

The density of a population can be regulated by various factors, including biotic and abiotic factors and population size. Density-dependent regulation can be affected by factors that affect birth and death rates such as competition and predation. Density-independent regulation can be affected by factors that affect birth and death rates such as abiotic factors and environmental factors, i.e. severe weather and conditions such as fire.

Density-dependent regulation:

In population ecology, density-dependent processes occur when population growth rates are regulated by the density of a population. Most density-dependent factors, which are biological in nature (biotic), include predation, inter- and intraspecific competition, accumulation of waste, and diseases such as those caused by parasites. Usually, the denser a population is, the greater its mortality rate. For example, during intra- and interspecific competition, the reproductive rates of the individuals will usually be lower, reducing their population’s rate of growth. In addition, low prey density increases the mortality of its predator because it has more difficulty locating its food source.

An example of density-dependent regulation is shown with results from a study focusing on the giant intestinal roundworm (Ascaris lumbricoides), a parasite of humans and other mammals. The data shows that denser populations of the parasite exhibit lower fecundity: they contained fewer eggs.

Fecundity as a Function of Population [2 00 Number of eggs per female 0 0 10 40 50 20 30 Number of worms

Density-independent regulation and interaction with density-dependent factors:

Many factors, typically physical or chemical in nature (abiotic), influence the mortality of a population regardless of its density. They include weather, natural disasters, and pollution. An individual deer may be killed in a forest fire regardless of how many deer happen to be in that area. Its chances of survival are the same whether the population density is high or low.

In real-life situations, population regulation is very complicated and density-dependent and independent factors can interact. A dense population that is reduced in a density-independent manner by some environmental factor(s) will be able to recover differently than would a sparse population. For example, a population of deer affected by a harsh winter will recover faster if there are more deer remaining to reproduce.