nature3


nature3


logo2-en1.jpg

Nature of Shiretoko (3)

~ Natural Environment ~
Ecosystem Forests Animals Landscape

Ecosystem
☆biodiversity from the ocean to the mountains
 Shiretoko’s plants and animals comprise a diverse ecosystem, spanning ocean, coast, and mountain, and preserved in a primeval state representative of Hokkaido’s original flora and fauna.
 In the oceans around Shiretoko, abundant phytoplankton support food chains that include rich marine life such as fish and marine mammals.  These phytoplankton, vital to Shiretoko’s marine ecology, grow in ideal conditions under the sea-ice that fills the sea around Shiretoko each winter.  Of regions that experience seasonal ice-floes, Shiretoko is located at the lowest latitude in the world.
pic0181.jpg
 Relatively large numbers of salmon and trout travel up Shiretoko’s rivers and streams to spawn every fall.  These fish provide a valuable food source for terrestrial mammals and birds, such as brown bears and Blakiston’s fish-owls, as well as supplementing the nutrition of the peninsula’s primeval forests.
 Thus, Shiretoko’s biodiversity allows for a thoroughly integrated ecosystem of both terrestrial and marine lives.
Forests
☆A mixture of evergreens and deciduous trees
 The mountains of Shiretoko are covered with rich primeval forests. A mixture of subarctic evergreen trees of spruce and fir species(e.g. Sakhalin fir Abies sachalinensis and Sakhalin spruce Picea glehnii),and cool temperate deciduous trees of oak species(e.g. Japanese oak Quercus mongolica var.grosseserrata and painted maple Acer mono)typifies the forests in Shiretoko.
pic0151.jpg
 The uniquness of Shiretoko's phytosociology lies in its vertical distribution. From the coast to the mountain peaks, an array of various vegetations are observed in layers: coastal vegetations-deciduous trees-mixtures of evergreen and decidous trees-birch species-pine and spruce species.
top of this page
Animals
 Shiretoko is an important breeding or wintering habitat for several globally threatened species. The followings are some examples of animals including those threatened species that can be seen in Shiretoko.
☆Mammals
○Brown Bears (Ursus arctors)
 Shiretoko is one of the most populous area for brown bears around the globe. The density of brown bears in the Shiretoko Peninsula ranges from estimates of between 7.3 and 14.1 bears per 100 square kilometers(Aoi,1981) to an estimate suggesting a minimum of 35bears per 100 square kilometers(Yamanaka et al.,1995).
 Shiretoko's brown bears are the only bears in Japan whose haitat area ranges from the coast to high mountains. A Shiretoko bear's diet includes over 90 types of plant and animal materials varying from salmon and trout to nuts, such as acorns.
○Marine mammals
 All the species of Pinnipedia that migrate to Japan are observed in the coastal waters of Shiretoko. With the southward move of the sea-ice in the winter, Pinnipedia species such as Steller sea lions Eumetopias jubatus, larga seals Phoca largha and ribbon seals P.fasciata migrate to Shiretoko area.
pic1042.jpg
 Shiretoko's coastal waters provide an important breeding and feeding habitat for those sea lions and seals and their pups.
 This coastal site is also important for the cetacean species for feeding and breeding, and it is also a part of the route in their seasonal migration. The cetacean species include Pacific white-sided dolphin Lagenorhynchus obliquidens, killer whale Orcinus orca and minke whale Balaenopiiera acutorostrata.
☆Birds
○Blakiston's fish-owl Ketupa blakistoni blakistoni
 Blakiston's fish-owl is one of the most endangered bird-species in the world. One of its two subspecies, Ketupa blakistoni blakistoni, is especially thought to be endangered as there are only 200 owls in the entire world. It is estimated that 120 of them inhabit in Hokkaido, and approximately a quater of them are in Shiretoko.
fishowl1.jpg
○Steller's sea eagle Haliaeetus pelagicus
 It is estimated that the number of this eagles is approximately 5,000 in the entire world, and Shiretoko is an important wintering site for more than 2,000 of this species.
pic1101.jpg
○White-tailed eagle H.albicilla
 Shiretoko provides a significant wintering site for white-tailed eagles, too, and as many as 600 of this species are counted up in the area.
 These eagles species help the ecosystem from sea to land as they feed upon salmon and trout that go upriver in the fall and walleye pollack Theragra chalcogramma in the winter.
top of this page
Landscape
 Shiretoko is the southernmost point in the northern hemisphere where sea ice covers the ocean in the winter. Long time erosion of the coastline, as well as the volcanic activities, has formed the unique landscape of precipiced cliff.
pic0111.jpg

index.gif

カテゴリー

page top