Friday, March 19, 2010

Biodiversity Loss (Endangered, Threatened and Extinct Species)

Endangered species


The Siberian Tiger is a subspecies of tiger that is endangered; three subspecies of tiger are already extinct.[1]
The most endangered asiatic top predator, the dhole is on the edge of extinction.

An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters. Also it could mean that due to deforestation there may be a lack of food and/or water. The International Union for Conservation of Nature (IUCN) has calculated the percentage of endangered species as 40 percent of all organisms based on the sample of species that have been evaluated through 2006.[2] (Note: the IUCN groups all threatened species for their summary purposes.) Many nations have laws offering protection to conservation reliant species: for example, forbidding hunting, restricting land development or creating preserves. Only a few of the many species at risk of extinction actually make it to the lists and obtain legal protection. Many more species become extinct, or potentially will become extinct, without gaining public notice.

Conservation status

Main article: Conservation status

The conservation status of a species is an indicator of the likelihood of that endangered species not living. Many factors are taken into account when assessing the conservation status of a species; not simply the number remaining, but the overall increase or decrease in the population over time, breeding success rates, known threats, and so on. The IUCN Red List is the best known conservation status listing.

Internationally, 190 countries have signed an accord agreeing to create Biodiversity Action Plans to protect endangered and other threatened species. In the United States this plan is usually called a species Recovery Plan.

IUCN Red List Endangered species

Endangered species under the IUCN Red List refers to a specific category of threatened species, and may include critically endangered species.

IUCN Red List of Threatened Species uses the term endangered species as a specific category of imperilment, rather than as a general term. Under the IUCN Categories and Criteria, endangered species is between critically endangered and vulnerable. Also critically endangered species may also be counted as endangered species and fill all the criteria

The more general term used by the IUCN for species at risk of extinction is threatened species, which also includes the less-at-risk category of vulnerable species together with endangered and critically endangered. IUCN categories include:

United States

"Endangered" in relation to "threatened" under the ESA.

Under the Endangered Species Act in the United States, "endangered" is the more protected of the two categories. The Salt Creek tiger beetle (Cicindela nevadica lincolniana) is an example of an endangered subspecies protected under the ESA.

In the United States alone, the “known species threatened with extinction is ten times higher than the number protected under the Endangered Species Act” (Wilcove & Master, 2008, p. 414). The US Fish and Wildlife Service as well as the National Marine Fisheries Service are held responsible for classifying and protecting endangered species, yet, adding a particular species to the list is a long, controversial process and in reality it represents only a fraction of imperiled plant and animal life (Wilcove & Master, 2008, p. 414).

Some endangered species laws are controversial. Typical areas of controversy include: criteria for placing a species on the endangered species list, and criteria for removing a species from the list once its population has recovered; whether restrictions on land development constitute a "taking" of land by the government; the related question of whether private landowners should be compensated for the loss of uses of their lands; and obtaining reasonable exceptions to protection laws.

Under the Bush administration, the former policy that required federal officials to consult a wildlife expert before taking actions that could damage endangered species was lifted. Under the Obama administration, this policy has been reinstated.[citation needed]

Being listed as an endangered species can have negative effect since it could make a species more desirable for collectors and poachers.[3] This effect is potentially reducible, such as in China where commercially farmed turtles may be reducing some of the pressure to poach endangered species.[4]

Another problem with the listing species is its effect of inciting the use of the "shoot, shovel, and shut-up" method of clearing endangered species from an area of land. Some landowners currently may perceive a diminution in value for their land after finding an endangered animal on it. They have allegedly opted to silently kill and bury the animals or destroy habitat, thus removing the problem from their land, but at the same time further reducing the population of an endangered species.[5] The effectiveness of the Endangered Species Act, which coined the term "endangered species", has been questioned by business advocacy groups and their publications, but is nevertheless widely recognized as an effective recovery tool by wildlife scientists who work with the species. Nineteen species have been delisted and recovered[6] and 93% of listed species in the northeastern United States have a recovering or stable population.[7]

Currently, 1,556 known species in the world have been identified as endangered, or near extinction, and are under protection by government law (Glenn, 2006, Webpage). This approximation, however, does not take into consideration the number of species threatened with endangerment that are not included under the protection of such laws as the Endangered Species Act. According to NatureServe’s global conservation status, approximately thirteen percent of vertebrates (excluding marine fish), seventeen percent of vascular plants, and six to eighteen percent of fungi are considered imperiled (Wilcove & Master, 2008, p. 415-416). Thus, in total, between seven and eighteen percent of the United States’ known animals, fungi, and plants are near extinction (Wilcove & Master, 2008, p. 416). This total is substantially more than the number of species protected under the Endangered Species Act in the United States, which means numerous species are inching closer and closer toward extinction.

Question of ethics

 This article may contain original research. Please improve it by verifying the claims made and adding references. Statements consisting only of original research may be removed. More details may be available on the talk page. (June 2009)

Even in the search to learn more about these species, many ecologists do not take into consideration the impact they leave on the environment and its inhabitants. It is apparent that the “quest for ecological knowledge, which is so critical for informing efforts to understand and conserve Earth’s biodiversity along with valued ecosystem goods and services, frequently raises complex ethical questions”,[8] and there is no clear way to identify and resolve these issues. Environmentalists tend to focus on the whole ecological sphere instead of the welfare of individual animals. Focusing on such a broad view tends to diminish the value of each individual creature. "Biodiversity conservation is currently a principle goal for resource management of 11.5% of the world’s surface area."[9] Large portions of life occur outside these protected areas and must be taken into consideration if the conservation of endangered species is going to be effective.[citation needed]

Impact on biodiversity and endangered species

In order to conserve the biodiversity of the planet, one must take into consideration the reasons why so many species are becoming endangered. “Habitat loss is the most widespread cause of species endangerment in the U.S., affecting 85% of imperiled species” (Wilcove & Master, 2008, p. 416). When an animal’s ecosystem is not maintained, they lose their home and are either forced to adapt to new surroundings or perish. Pollution is another factor that causes many species to become endangered, especially a large proportion of aquatic life. Also, over-exploitation, disease (Wilcove & Master, 2008, p. 416), and climate change (Kotiaho et al., 2005, p. 1963) have led to the endangerment of several species.

However, the most important factor leading to the endangerment of the majority of wildlife in the world is the human impact on the species and their environment. “As human use of resources, energy, and space intensified over the past few centuries, the diversity of life has been substantially diminished in most parts of the world” (Ishwaran & Erdelen, 2006, p.179). Basically, as the human impact on the environment increases, the diversity of life decreases. Humans are constantly using the resources and space of other species for themselves, negatively impacting the survival rate of many creatures.

Humans also set standards for which species they think should be saved and which species they find unimportant or undesirable. For example, the coqui frog, an invasive species in Hawaii, is so common there that its “nocturnal singing” reduces the value of homes and prevents hotels from using rooms near forests. Hawaiians have proposed eliminating the frog, and several wildlife managers want to release a pathogen to kill the frogs (Minteer & Collins, 2005, p. 333). The frog has decreased the value of homes and caused a loss of business for several hotels, so the Hawaiians decided it was acceptable to get rid of the group of coqui frog living near them.

Another example where the human impact affected the welfare of a species sex in the instance of non-native mute swans establishing themselves at Arrowhead Lake in Vermont. When the population of swans grew to eight birds, the Vermont Fish and Wildlife Department decided to take action. Two swans were eventually killed, angering animal welfare organizations and people living near the lake (Minteer & Collins, 2005, p. 333). The case of the Arrowhead Lake swans demonstrates what one considers the natural environment based on human assumptions. Simply because the swans were not normally living there does not mean it is not part of their natural habitat, and there is certainly no reason for them to be destroyed because of human dissatisfaction.

Yet another example of the human impact in the lives of endangered species is that of the Preble’s meadow jumping mouse. Research has shown that the mouse is not taxonomically different from the Bear Lodge meadow jumping mouse and the US Fish and Wildlife Service has proposed removing the Preble’s mouse from the endangered species list based on this information (Minteer & Collins, 2005, p. 333).

A final example of the human impact on existing species is the issue of toe clipping in ecological research. While ecologists are doing research on different species to advance their knowledge of methods of conservation, they must take into consideration the impact they have on the wildlife they are studying. Toe clipping “has been reported to result in a number of adverse effects on the animals, including inflammation and infection of the feet and limbs” (Minteer & Collins, 2005, p. 334). This example demonstrates how humans must take into consideration the well-being of the animal even before they perform research to help conserve the species. The human impact on species and their environments has many negative effects. It is important for humans to help maintain all species in the world and not deter their development.

Species maintaining importance

“Diversity of life and living systems are a necessary condition for human development” (Ishwaran & Erdelen, 2006, p.179). Many question the importance of maintaining biodiversity in today’s world, where conservation efforts prove costly and time consuming. The fact is that the preservation of all species is necessary for human survival. Species should be saved for “aesthetic and moral justifications; the importance of wild species as providers of products and services essential to human welfare; the value of particular species as indicators of environmental health or as keystone species crucial to the functioning of ecosystems; and the scientific breakthroughs that have come from the study of wild organisms” (Wilcove & Master, 2008, p. 418). In other words, species serve as a source of art and entertainment, provide products such as medicine for human well-being, indicate the welfare of the overall environment and ecosystem, and provided research that resulted in scientific discoveries. An example of an “aesthetic justification” in conserving endangered species is that of the introduction of the gray wolf into Yellowstone National Park. The gray wolf has brought numerous amounts of tourists to the park and added to the biodiversity in the protected region (Wilcove & Master, 2008, p. 418).

Another example, supporting the conservation of endangered species as providers of products for human well-being, is the scrub mint. It has been found that the scrub mint contains an anti-fungal agent and a natural insecticide (Wilcove & Master, 2008, p. 418). Also, the deterioration of the bald eagle and the peregrine falcon “alerted people to the potential health hazards associated with the widespread spraying of DDT and other persistent pesticides” (Wilcove & Master, 2008, p. 418).

This serves as an example of how certain fish can serve as identifiers of environmental health and protect human life as well as other species. Finally, an example of species providing for scientific discoveries is the instance of the Pacific yew which “became the source of taxol, one of the most potent anticancer compounds ever discovered” (Wilcove & Master, 2008, p. 418-419). Endangered species could prove useful to human development, maintenance of biodiversity and preservation of ecosystems.

Another approach is known as ecosystem conservation, where a focus is placed less on preserving any individual given species than on preserving the proper functioning of the ecosystem as a whole.[10]

[edit] Helping preserve endangered species

It is the goal of conservationists to create and expand upon ways to preserve endangered species and maintain biodiversity. There are several ways in which one can aid in preserving the world’s species who are nearing extinction. One such way is obtaining more information on different groups of species, especially invertebrates, fungi, and marine organisms, where sufficient data is lacking.

For example, to understand the causes of population declines and extinction an experiment was conducted on the butterfly population in Finland. In this analysis, the butterflies’ endangered list classification, distribution, density, larval specificity, dispersal ability, adult habitat breadth, flight period and body size were all recorded and examined to determine the threatened state of each species. It was found that the butterflies’ distribution has declined by fifty-one and a half percent, and they have a severely restricted habitat. One example of specific butterflies who have a declining distribution rate are the Frigga’s Fritillary and Grizzled Skipper, who have been affected by habitat loss due to extensive draining of the bogs where they live (Kotiaho et al., 2005, p. 1963-1967). This experiment proves that when we know the causes of endangerment, we can successfully create solutions for the management of biodiversity.

Another way to help preserve endangered species is to create a new professional society dedicated to ecological ethics. This could help ecologists make ethical decisions in their research and management of biodiversity. Also, creating more awareness on environmental ethics can help encourage species preservation. “Courses in ethics for students, and training programs for ecologists and biodiversity managers” all could create environmental awareness and prevent violations of ethics in research and management (Minteer & Collins, 2005, p. 336). One final way in which one can conserve endangered species is through federal agency investments and protection enacted by the federal government. “Ecologists have proposed biological corridors, biosphere reserves, ecosystem management, and ecoregional planning as approaches to integrate biodiversity conservation and socioeconomic development at increasingly larger spatial scales” (Ishwaran & Erdelen, 2006, p.179).

One example of a federal mandated conservation zone is the Northwest Hawaiian Islands Marine National Monument, the largest marine protected area in the world. The monument is essential to the preservation of underwater communities and overfished regions. Only researchers working in the area are permitted to fish, no corals may be removed, and the Department of Homeland Security will enforce restrictions on vessels passing through the waters via satellite imaging. The monument will serve as a home to an estimated seven thousand species, most of which cannot be found anywhere else in the world (Raloff, 2006, p. 92). This environmental monument demonstrates the fact that it is possible to create a safe environment for endangered species, as well as maintaining some of the world’s largest ecosystems.

Captive breeding programs

Main article: Captive breeding

Captive breeding is the process of breeding rare or endangered species in human controlled environments with restricted settings, such as wildlife preserves, zoos and other conservation facilities. Captive breeding is meant to save species from going extinct. It is supposed to stabilize the population of the species so it is no longer at risk for disappearing.[11]

This technique has been used with success for many species for some time, with probably the oldest known such instances of captive mating being attributed to menageries of European and Asian rulers, a case in point being the Pere David's Deer. However, captive breeding techniques are usually difficult to implement for highly mobile species like some migratory birds (eg. cranes) and fishes (eg. Hilsa). Additionally, if the captive breeding population is too small, inbreeding may occur due to a reduced gene pool; this may lead to the population lacking immunity to diseases.

Legal private farming for profit

Whereas poaching causes substantial reductions in endangered animal populations, legal private farming for profit has the opposite effect. Legal private farming has caused substantial increases in the populations of both the southern black rhinoceros and the southern white rhinoceros. Dr Richard Emslie, a scientific officer at the IUCN, said of such programs, "Effective law enforcement has become much easier now that the animals are largely privately owned... We have been able to bring local communities into the conservation programmes. There are increasingly strong economic incentives attached to looking after rhinos rather than simply poaching: from eco-tourism or selling them on for a profit. So many owners are keeping them secure. The private sector has been key to helping our work. " [12]

Conservation experts view the effect of China's turtle farming on the wild turtle populations of China and South-Eastern Asia - many of which are endangered - as "poorly understood".[13] While they commend the gradual replacement of wild-caught turtles with farm-raised ones gradually in the marketplace ( the percentage of farm-raised individuals in the "visible" trade growing from around 30% in 2000 to around 70% ca. 2007),[14] they are concerned with the fact that a lot of wild animals are caught to provide farmers with the breeding stock. As the conservation expert Peter Paul van Dijk noted, turtle farmers often believe in the superiority of wild-caught animals as the breeding stock, which may create an incentive for turtle hunters to seek and catch the very last remaining wild specimens of some endangered turtle species.[14]

In 2009, researchers in Australia managed for the first time to coax southern bluefin tuna to breed in landlocked tanks, opening up the possibility of using fish farming as a way to save the species from the problems of overfishing in the wild.[15]

Gallery

The endangered Island Fox

The endangered Sea Otter

The most endangered asiatic top predator, the dhole

American Bison skull heap. There were as few as 750 bison in 1890 from economic-driven overhunting.

Immature California Condor

Loggerhead Sea Turtle

Santa Cruz Long-toed Salamander (photo courtesy of Don Roberson)

An asian arowana

Iberian Lynx, Europe's most endangered mammal



Threatened species


The threatened categories (IUCN Red List)

Threatened species are any species (including animals, plants, fungi, etc.) which are vulnerable to extinction in the near future. World Conservation Union (IUCN) is the foremost authority on threatened species, and treats threatened species not as a single category, but as a group of three categories: vulnerable, endangered, and critically endangered, depending on the degree to which they are threatened.

Species that are threatened are sometimes characterised by the population dynamics measure of critical depensation, a mathematical measure of biomass related to population growth rate. This quantitative metric is one method of evaluating the degree of endangerment.

Less-than-threatened categories are Near Threatened, Least Concern, and the no longer assigned category of Conservation Dependent. Species which have not been evaluated (NE), or do not have sufficient data (Data Deficient) also are not considered "threatened" by the IUCN.

Although threatened and vulnerable may be used interchangeably when discussing IUCN categories, the term threatened is generally used to refer to the three categories (critically endangered, endangered and vulnerable), while vulnerable is used to refer to the least at risk of those three categories. They may be used interchangeably in most contexts however, as all vulnerable species are threatened species (vulnerable is a category of threatened species); and, as the more at-risk categories of threatened species (namely endangered and critically endangered) must, by definition, also qualify as vulnerable species, all threatened species may also be considered vulnerable.

Threatened species are also referred to as a red-listed species, as they are listed in the IUCN Red List of Threatened Species.

Subspecies, populations and stocks may also be classified as threatened.

United States definition

"Threatened" in relation to "endangered" under the ESA.

Under the Endangered Species Act in the United States, "threatened" is defined as "any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range".[1] It is the less protected of the two protected categories. The Bay checkerspot butterfly (Euphydryas editha bayensis) is an example of a threatened subspecies protected under the ESA.

Within the U.S., state wildlife agencies have the authority under the ESA to manage species which are considered endangered or threatened within their state but not within all states, and which therefore are not included on the national list of endangered and threatened species. For example, the Trumpeter Swan (Cygnus buccinator) is threatened in the state of Minnesota, while large populations still remain in Canada and Alaska.[2]

Australian definition

The Commonwealth of Australia has a legal framework for categorising and protecting endangered species, namely the Environment Protection and Biodiversity Conservation Act 1999, which is known in short as the EPBC Act. This Act has six categories[3]; Extinct, Extinct in the wild, Critically endangered, Endangered, Vulnerable, and Conservation dependent, defined in Section 179 of the Act, and could be summarised as; "Extinct" - "no reasonable doubt that the last member of the species has died", "Extinct in the wild" - "known only to survive in cultivation" and "despite exhaustive surveys" has not been seen in the wild, "Critically endangered" - "extremely high risk of extinction in the wild in the immediate future", "Endangered" - "very high risk of extinction in the wild in the near future", "Vulnerable" - "high risk of extinction in the wild in medium-term future", and "Conservation dependent" - "focus of a specific conservation program" without which the species would enter one of the above categories.

The EPBC Act also recognises and protects threatened ecosystems such as plant communities, and Ramsar Convention wetlands used by migratory birds.

Individual states and territories of Australia are bound under the EPBC Act, but may also have legislation which gives further protection to certain species, for example Western Australia's Wildlife Conservation Act 1950. Some species, such as Lewin's Rail (Lewinia pectoralis), are not listed as threatened species under the EPBC Act, but they may be recognised as threatened by individual states or territories.


EXTINCT SPECIES


Prehistoric










Prehistoric animals represent the vast majority of extinct animals. Thru Paleontological exploration, scientists are slowly piecing together evolution from the fist sea dwelling organisms to present day species. There will always be much speculation as to what caused the extinction of the dinosaurs.


Below is a chart indicating the various eras and periods, as well at the species which were first introduced at the time.

Era Cenozoic Mesozoic Paleozoic
Period Quaternary
First Humans

3 to 0 Million Years Ago. From the Ice Age to the Appearance of the first human beings.

Cretaceous
Dinosaur
Birds
Mammals

144 to 65 Million Years ago. Last part Of the age of Dinosaurs

Carboniferous
Amphibians
Early Reptiles

360 to 248 million years ago. Appearance of the first reptiles (laying their eggs on land).

Tertiary
Dinosaur Extinction

65 to 3 Million Years Ago. Dinosaurs inexplicably become extinct and mammals and birds become the dominant species.

Jurassic
Dinosaurs
Birds
Mammals

206 to 144 Million Years ago. This is the high point of the dinosaur age, there are a great number of species including giant plant eaters. Appearance of the first feathered birds.

Devonian
Amphibians
Fish

408 to 360 Million Years Ago. Appearance of the first amphibious creatures.

Triassic
Dinosaurs
Mammals

248 to 206 Million Years Ago. Appearance of the The first dinosaurs and the first mammals.

Silurian
Fish

438 to 408 Million Years Ago. Plants begin to cover the land.

Ordovician
Marine Invertebrates
Fish

505 to 438 Million Years Ago. The Oceans are teeming with invertebrate life. Appearance of he first true fish.

Cambrian
Marine Invertebrates

570 to 505 Million Years Ago. Appearance of the first marine invertebrates.

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Sunday, March 14, 2010

Population Growth (Phil. Setting/Current data of Phil. population/Family Planning/Unemployment/Rapid Urbanization)

Population growth

Past and projected human population on different continents. The vertical axis is logarithmic and its scale is millions of people.

Population growth is the change in a population over time, and can be quantified as the change in the number of individuals of any species in a population using "per unit time" for measurement. In biology, the term population growth is likely to refer to any known organism, but this article deals mostly with the application of the term to human populations in demography.

In demography, population growth is used informally for the more specific term population growth rate (see below), and is often used to refer specifically to the growth of the human population of the world.

Simple models of population growth include the Malthusian Growth Model and the logistic model.

Contents

Population growth rate

In demographics and ecology, Population growth rate (PGR) is the fractional rate at which the number of individuals in a population increases. Specifically, PGR ordinarily refers to the change in population over a unit time period, often expressed as a percentage of the number of individuals in the population at the beginning of that period. This can be written as the formula:

\mathrm{Growth\ rate} = \frac{(\mathrm{population\ at\ end\ of\ period}\ -\ \mathrm{population\ at\ beginning\ of\ period})} {\mathrm{population\ at\ beginning\ of\ period}}

(In the limit of a sufficiently small time period.)

The above formula can be expanded to: growth rate = crude birth rate - crude death rate + net immigration rate, or ∆P/P = (B/P) - (D/P) + (I/P) - (E/P), where P is the total population, B is the number of births, D is the number of deaths, I is the number of immigrants, and E is the number of emigrants.

This formula allows for the identification of the source of population growth, whether due to natural increase or an increase in the net immigration rate. Natural increase is an increase in the native-born population, stemming from either a higher birth rate, a lower death rate, or a combination of the two. Net immigration rate is the difference between the number of immigrants and the number of emigrants.

The most common way to express population growth is as a ratio, not as a rate. The change in population over a unit time period is expressed as a percentage of the population at the beginning of the time period. That is:

\mathrm{Growth\ ratio} = \mathrm{Growth\ rate} \times 100%.

A positive growth ratio (or rate) indicates that the population is increasing, while a negative growth ratio indicates the population is decreasing. A growth ratio of zero indicates that there were the same number of people at the two times -- net difference between births, deaths and migration is zero. However, a growth rate may be zero even when there are significant changes in the birth rates, death rates, immigration rates, and age distribution between the two times. [1] Equivalently, percent death rate = the average number of deaths in a year for every 100 people in the total population.

A related measure is the net reproduction rate. In the absence of migration, a net reproduction rate of more than one indicates that the population of women is increasing, while a net reproduction rate less than one (sub-replacement fertility) indicates that the population of women is decreasing.

Human population growth rate

Annual population growth rate in percent, as listed in the CIA World Factbook (2006 estimate).[2]
Growth rate of world population (1950-2000)
Population of the world from 10,000 BCE to 2000 CE (logarithmic scale)

Globally, the growth rate of the human population has been steadily declining since peaking in 1962 and 1963 at 2.20% per annum. In 2009 the estimated annual growth rate was 1.10%.[3] The last one hundred years have seen a rapid increase in population due to medical advances and massive increase in agricultural productivity[4] made possible by the Green Revolution.[5][6][7]

The actual annual growth in the number of humans fell from its peak of 88.0 million in 1989, to a low of 73.9 million in 2003, after which it rose again to 75.2 million in 2006. Since then, annual growth has declined. In 2009 the human population increased by 74.6 million, and it is projected to fall steadily to about 41 million per annum in 2050, at which time the population will have increased to about 9.2 billion.[8] Each region of the globe has seen great reductions in growth rate in recent decades, though growth rates remain above 2% in some countries of the Middle East and Sub-Saharan Africa, and also in South Asia, Southeast Asia, and Latin America.[9]

Some countries experience negative population growth, especially in Eastern Europe (mainly due to low fertility rates and emigration). In Southern Africa, growth is slowing due to the high number of HIV-related deaths. Some Western Europe countries might also encounter negative population growth.[10] Japan's population began decreasing in 2005 [11]

Excessive growth and decline

Main articles: Overpopulation and population decline

Population exceeding the carrying capacity of an area or environment is called overpopulation. It may be caused by growth in population or by reduction in capacity. Spikes in human population can cause problems such as pollution and traffic congestion, these might be resolved or worsened by technological and economic changes. Conversely, such areas may be considered "underpopulated" if the population is not large enough to maintain an economic system (see population decline). Between these two extremes sits the notion of the optimum population.

See also

Estimated size of human population from 10,000 BCE–2000 CE.

References

  1. ^ Association of Public Health Epidemiologists in Ontario
  2. ^ Population growth rate
  3. ^ U.S. Census Bureau, January 2010
  4. ^ BBC NEWS | The end of India's green revolution?
  5. ^ Food First/Institute for Food and Development Policy
  6. ^ Rising food prices curb aid to global poor
  7. ^ Record rise in wheat price prompts UN official to warn that surge in food prices may trigger social unrest in developing countries
  8. ^ U.S. Census Bureau, January 2010
  9. ^ U.S. Census Bureau, June 2009
  10. ^ UN population projections
  11. ^ Japan sees biggest population fall

External links


POPULATION

Philippines Table of Contents

Population Growth

The Philippine population in the early 1990s continued to grow at a rapid, although somewhat reduced rate from that which had prevailed in the preceding decades. In 1990 the Philippine population was more than 66 million, up from 48 million in 1980. This figure represents an annual growth rate of 2.5 percent, down from 2.6 percent in 1980 and from more than 3 percent in the 1960s. Even at the lower growth rate, the Philippine population will increase to an estimated 77 million by the year 2000 and will double every twenty-nine years into the next century. Moreover, in 1990 the population was still a youthful one, with 57 percent under the age of twenty. The birth rate in early 1991 was 29 per 1,000, and the death rate was 7 per 1,000. The infant mortality rate was 48 deaths per 1,000 live births. Population density increased from 160 per square kilometer in 1980 to 220 in 1990. The rapid population growth and the size of the younger population has required the Philippines to double the amount of housing, schools, and health facilities every twenty-nine years just to maintain a constant level.

Migration

There were two significant migration trends that affected population figures in the 1970s and the 1980s. First was a trend of migration from village to city, which put extra stress on urban areas. As of the early 1980s, thirty cities had 100,000 or more residents, up from twenty-one in 1970. Metro Manila's population was 5,924,563, up from 4,970,006 in 1975, marking an annual growth rate of 3.6 percent. This figure was far above the national average of 2.5 percent. Within Metro Manila, the city of Manila itself was growing more slowly, at a rate of only 1.9 percent per annum, but two other cities within this complex, Quezon City and Caloocan, were booming at rates of 4 percent and 3.5 percent, respectively.

A National Housing Authority report revealed that, in the early 1980s, one out of four Metro Manila residents was a squatter. This figure represented a 150 percent increase in a decade in the number of people living in shantytown communities, evidence of continuing, virtually uncontrolled, rural-urban migration. The city of Manila had more than 500,000 inhabitants and Quezon City had 371,000 inhabitants in such neighborhoods. Moreover, rural-urban migrants, responding to better employment opportunities in peripheral metropolitan cities such as Navotas, had boosted the percentage of squatters in that city's total population.

A second major migration pattern consisted of resettlement from the more densely to the less densely populated regions. As a result of a population-land ratio that declined from about one cultivated hectare per agricultural worker in the 1950s to about 0.5 hectare by the early 1980s, thousands of Filipinos had migrated to the agricultural frontier on Mindanao. According to the 1980 census, six of the twelve fastest growing provinces were in the western, northern, or southern Mindanao regions, and a seventh was the frontier province of Palawan. Sulu, South Cotabato, Misamis Oriental, Surigao del Norte, Agusan del Norte, and Agusan del Sur provinces all had annual population growth rates of 4 percent or more, a remarkable statistic given the uncertain law-and-order situation on Mindanao. Among the fastestgrowing cities in the late 1970s were General Santos (10 percent annual growth rate), Iligan (6.9), Cagayan de Oro (6.7), Cotabato (5.7), Zamboanga (5.4), Butuan (5.4), and Dipolog (5.1)--all on Mindanao.

By the early 1980s, the Mindanao frontier had ceased to offer a safety valve for land-hungry settlers. Hitherto peaceful provinces had become dangerous tinderboxes in which mounting numbers of Philippine army troops and New People's Army insurgents carried on a sporadic shooting war with each other and with bandits, "lost commands," millenarian religious groups, upland tribes, loggers, and Muslims. Population pressures also created an added obstacle to land reform. For years, there had been demands to restructure land tenure so that landlords with large holdings could be eliminated and peasants could become farm owners. In the past, land reform had been opposed by landlords. In the 1990s there simply was not enough land to enable a majority of the rural inhabitants to become landowners. International migration has offered better economic opportunities to a number of Filipinos without, however, reaching the point where it would relieve population pressure. Since the liberalization of United States immigration laws in 1965, the number of people in the United States having Filipino ancestry had grown substantially to 1,406,770 according to the 1990 United States census. In the fiscal year ending September 30, 1990, the United States Embassy in Manila issued 45,189 immigrant and 85,128 temporary visas, the largest number up to that time.

In addition to permanent residents, in the late 1980s and early 1990s, more than half a million temporary migrants went abroad to work but maintained a Philippine residence. This number included contract workers in the Middle East and domestic servants in Hong Kong and Singapore, as well as nurses and physicians who went to the United States for training and work experience, a fair proportion of whom managed to become permanent residents. The remittances sent back to the Philippines by migrants have been a substantial source of foreign exchange.

Population Control

Popcom was the government agency with primary responsibility for controlling population growth. In 1985 Popcom set a target for reducing the growth rate to 1 percent by 2000. To reach that goal in the 1990s, Popcom recommended that families have a maximum of two children, that they space the birth of children at three-year intervals, and that women delay marriage to age twenty-three and men to age twenty-five.

During the Marcos regime (1965-86), there was a rather uneasy accommodation between the Catholic hierarchy and the government population control program. Bishops served on Popcom, and the rhythm method was included by clinics as a birth-control method about which they could give information. A few Catholic priests, notably Frank Lynch, even called for energetic support of population limitation.

The fall of Marcos coincided with a general rise of skepticism about the relation between population growth and economic development. It became common to state that exploitation, rather than population pressure, was the cause of poverty. The bishops withdrew from the Popcom board, opposed an effort to reduce the number of children counted as dependents for tax purposes, secured the removal of the population-planning clause from the draft of the Constitution, and attempted to end government population programs. Attacks on the government population program were defeated, and efforts to popularize family planning, along with the provision of contraceptive materials, continued. In the early 1990s, however, the program generally lacked the firm government support needed to make it effective.

Ethnicity, Regionalism, and Language

For more recent population estimates, see Facts about the Philippines.

Source: U.S. Library of Congress




What are the causes of population growth?

causes of population growth are lacking of education,wars, increasing illegal refugees and migrant.

No not necessarily.The basic reasons for growth of population are

1Increase in birth rate(due to lack of awareness,lack of education,desire for sons,early marriages,custom and culture and infant mortality rate)

2.Increase in net migration

This is calculated by the formula

Avg no of emmigrants-immigrants

3.The death rate.Higher the death rate lower the population growth

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