Biodiversity Hotspots - Mandarin High School
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Transcript Biodiversity Hotspots - Mandarin High School
Biodiversity Hotspots
The Archipelago of Japan
Overview
• The archipelago of Japan consists of more than 3,000 islands. The
archipelago stretches across vast climate regions- the humid subtropics
in the south and the boreal, temperate climate in the north. This wide
stretch and the isolation of the islands cause the endemism and unique
biodiversity that makes this archipelago a hotspot. Moreover, Japan
is located at an intersection of three tectonic plates, where plate sliding
causes volcanic eruptions, hotsprings, mountains, and earthquakes.
Japan has vegetation ranging from boreal mixed forests to subtropical
broadleaf evergreen forests. About 73% of Japan is made up of
mountains and it contains many endemic species such as the Okinawa
woodpecker and the famous snow monkeys.
Vital Statistics
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Hotspot Original Extent (square km) – 373,490
Hotspot Vegetation Remaining (square km) – 74,698
Endemic Plant Species – 1,950
Endemic Threatened Birds - 10
Endemic Threatened Mammals – 21
Endemic Threatened Amphibians – 19
Extinct Species – 7
Human Population Density (people/ square km) – 336
Area Protected (square km) – 62,025
Area Protected (square km) in Categories 1-4 – 21,918
*Categories I-IV afford higher levels of protection
.
Snow Monkey
Japanese Serow
Okinawa Rail
Biodiversity and Endemism
Taxonomic Group Species Endemic Species Percent Endemism
Plants
Mammals
Reptiles
Birds
Amphibians
Freshwater Fish
5,600
94
366
66
50
214
1,950
46
13
28
44
52
34.8
48.9
3.6
42.4
88.0
24.3
Endemic Plants
• There are about 5,600 vascular plants on Japan, and a third of these are
thought to be endemic. Japan also has three endemic plant families:
Sciadopityaceae, Glaucidiaceae, and Pteridophyllaceae. Japan’s flora came from
east-central China, Korea, and the islands and mainland to the north. One of the
endemic plant speices of Japan is the Shirane-aoi ( Glaucidium palmatum),
which has blue-purple and white flowers. The Togakushisgouma ( Ranzania
japonica) and the Urahagusa ( Hakonechloa macra) are also endemic plants
that are garden favorites. All in all, about 90 of Japan’s endemic plant genera
are thought to be part of an ancient lineage that was introduced during the
Tertiary Period.
Endemic Birds
• Out of the 370 known bird species in
Japan, only about 13 are endemic.
The Okinawa woodpecker was once
close to extinction in the 1930’s but is
now close to 146 to 584 in numbers.
The Okinawa rail also an endemic
bird found only on Yanbaru. It is
endangered due to logging and alien
invasive species, and only about 900
pairs of this bird are estimated to
exist.
Endemic Mammals
• About 90 species of mammals inhabit
Japan, and around half of these are
endemic. Sado Island carries two of
these endemic species – the Sado shrew
and the Sado mole. The Japanese
dormouse, amami rabbit, and the
Ryukyu long-tailed giant rat are the
three monotypic genera of the six
endemic genera species. The most
renowned monkey, the Japanese
macaque (snow monkey) lives on
Honshu. It is the most northerly living
mammal in the world. The Iriomote cat
is almost extinct with only about 100
individuals left.
Endemic Reptiles and Amphibians
• Japan has over 65 reptiles, of which
about 30 are endemic. The Okinawa
black-breasted leaf-turtle, the
Kikuzato’s brook snake, and the
Tokashiki ground gecko are all
endemic to the islands. In Japan,
endemism for amphibians is high,
with about 44 species out of the 50
being endemic. The Hynobius and
Oki salamander (confined to Dogo)
are two amphibian species limited to
islands. The Japanese giant
salamander is one of the world’s
largest amphibian.
Endemic Freshwater Fish and Invertebrates
• Japan has almost 215 native fish species, of which more than
50 are endemic. Japan holds a large amount of the
evolutionary history of fishes. Minnows and loaches have
been diversified within the hotspot. Tiger beetles and nearly
240 butterfly species are native to the Japanese islands.
Human Impact
• Japan has a human population of about 127.5 million people, of which 70
percent live on only 3% of the total land area. Thus, much of the land is
considered undeveloped; still, only about 20% of the original vegetation remains.
Although there are plantations in Japan, its remaining forests are not threatened
due to high cost of native timber and cheaper imports from other countries. The
steady increase in automobiles and roads, and the growing desire for ski resorts,
golf courses, etc have created a strain on the environment. Public transportation
has made it much easier to travel to remote, untouched natural areas. Wetlands
and coastal regions are being destroyed by agriculture, roads, and urban
development. One third of Kushiro’s marshland has been converted for
agricultural and residential use. The Indian grey mongoose, Javan mongoose,
and Siberian weasel are all introduced non-native species that threaten native
species such as the Okinawa rail.
Conservation Action
• Japan has many national parks(28) and other small
protected parks and wildlife protection zones. However, only
about 6% of the hotspot falls in the protected region in
IUCN categories. The Japanese Government is one of five
partners in the Critical Ecosystem Partnership, which provides $125
million over five years for conservation in the hotspots. There is a
widespread environmental concern in Japan, and it has two Natural
World Heritage Sites, which contain ancient Japanese cedar trees.
In many areas, Japan fails to protect critically endangered species.
Works Cited
• (2007). Biodiversity Hotspots. Retrieved February 11,
2008, from Conservation International Web site:
http://www.biodiversityhotspots.org/xp/hotspots/japan/Pa
ges/default.aspx