Chichijima Island As a World Natural Heritage Site Ecosystem: Notable Example of Biological Evolutionary Process
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Value of Chichijima Island as a World Natural Heritage site Ecosystem: notable example of biological evolutionary process In the Ogasawara Islands, we can find numbers of endemic species that have evolved into various The adaptations of plant structures forms in small islands isolated by the sea. The on- depend on where the plants grow. going evolutionary processes of animals and plants Chichijima can be witnessed here. Land Snails Island Among the various animals and plants found in Many plants of Ogasawara Plants spread across Their structures evolved Ogasawara, snails are a representative group of Natural Heritage Guide originate in Southeast Asia various areas on the to suit the environment. and Okinawa. island. animals that have attained diverse evolution. At least 90% of the snails are endemic species. In particular, snails belonging to the Mandarina genus have differentiated into various shapes and colors as a result of evolutionary processes to adapt to specific habitats, such as trees and the ground. An arboreal species that lives at upper parts of trees. It has a tall and small shell with light color. Mandarina suenoae Sclerophyllous scrub A semi-arboreal species Forest of relatively short trees distributed in the that lives on barks of northeastern and southwestern parts of Chichijima trees. It has a flat and small shell with slightly light color. Island. The forest consists of many endemic plants that have evolved to tolerate the dry weather. 80% of trees growing here are endemic species. rpa glab Mandarina hirasei llica ra Ca A ground dwelling species pa that lives on the ground. arpa rvifo llic lia It has a flat shell with Ca dark color. Mandarina mandarina Callicarpa parvifolia (endemic species) which grows in dryer environment than C. glabra (also endemic species) has Length of smaller and thicker leaves. Mandarina Reasons for Ogasawara Animals & Plants Changing ecosystem being inscribed In the Ogasawara Islands, a large number of The original ecosystem of Ogasawara is as a World Natural endemic species are distributed in small islands. changing because of the impact of animals Heritage site Chichijima Island is an important breeding site and plants brought in by people for the Bonin flying fox and the endemic (alien species). As a result of unique subspecies of Japanese wood-pigeon. evolution in small islands The original ecosystem of isolated by the sea, a large Eurasian buzzard Ogasawara number of endemic creatures Ogasawara endemic before humans and their ecosystems can be subspecies Japanese and alien observed in Ogasawara. This wood-pigeon Seabird organisms was valued highly and these Japanese arrived: It is a type of pigeon Wood-pigeon islands were designated as a with a purplish-red Bonin colored head. flying fox World Natural Heritage site Chichijima Island is an in June 2011. important breeding site. Natural monument. Meimuna boninensis Mandarina mandarina Characteristics Pandanus Livistona Ogasawara boninensis chinensis var. of Chichijima Island endemic Rhododendron boninensis species boninense Chichijima Island encompasses the largest area Bonin 2 flying fox (23.8 km ) of the Ogasawara Islands. There are Callicarpa Elaeocarpus The Bonin flying fox is parvifolia photiniaefolius many endemic species, inhabiting various the only land mammal in Ogasawara. environments on this island, such as the Chichijima is an important breeding 300-meter high mountains. site where 100 to 160 individuals inhabit. Natural monument. The changing Eurasian ecosystem of buzzard Ogasawara Wild cat after humans Meimuna and alien organisms boninensis Black rat arrived: It is the only cicada living Green anole on the Ogasawara Islands and comes out in autumn. Ogasawara Natural monument. Feral goat endemic Predatory species flatworm Casuarina equisetufolium Chichijima Island endemic species Bischofia javanica Rhododendron Leucaena boninense leucocephala Ogasawara Islands Branch 2012 March Registration No. (23) 9 Office,Tokyo Metropolitan It grows only on Various measures taken to restore the Produced/published by: Ogasawara Islands Branch Chichijima Island. Government Office,Tokyo Metropolitan Government Nishimachi, Chichijima, Ogasawara Only one strain of original ecosystem of Ogasawara. Village, Tokyo, 100-2101 Photography: Satoshi Chiba this plant grows in TEL : +81(0)4998-2-2123 Edited by: PREC Institute Inc. the wild. FAX : +81(0)4998-2-2302 Illustration & Disign: HABAAlisa See next page for details. Map of the Chichijima Island H y Natural Heritage er rt it e Rules to protect age prop the natural Measures against Road Anijima Casuarina equisetufolium environment Trail of Ogasawara Island Sclerophyllous Measures against scrub To prevent feral goats invasions of The endemic subspecies Land snails of Eurasian buzzard alien species: Please do not Boninagrion ezoin bring in plants, Measures against Wrong? animals, soil, black rats or seedlings with soil. Ogasawara Village Seeds and Tourist Association small insects Japanese wood-pigeon may live in Visitor sanctuary the soil. Center Stop! le Tra Ano p To prevent Measures against the spread of green anoles alien species: Brush off all Sclerophyllous traces of soil scrub when you go Land snails out. Cleaning the soles In order to protect suitable of shoes breeding sites for the endemic Some seeds Insects subspecies of Japanese can stick to Seeds your clothes. wood-pigeon, a protected area Soil Small has been set up at Higashidaira. animals Do not roll up your pants. You must be accompanied by a Sclerophyllous guide to enter the forest. Check the soles scrub of your shoes. Measures against Casuarina equisetufolium To protect Bonin flying fox Measures against Land snails the home of feral goats Follow the endemic species: designated route. For information about guided tours: Fence s fo Ogasawara Village Tourist r Japanese Measures against w wood-pigeon Association (B-ship) i l wild cats d c a t +81 (0)4998 2 2587 s / fe r Open: 365 days a Forests are home l g to many different o a 8:00 12:00, 13:30 17:00 living things. ts Measures against Measures against For more information: feral goats feral goats Land snails Ogasawara Visitor Center A unique landscape Sclerophyllous +81 (0)4998 2 3001 formed by limestone can scrub be observed around Open: during times the Ogasawara Maru is in port Minamijima Island. In (Open every day during tourist season) particular, the landscape called “submerged karst”, the karst 8:30 17:00 formation of eroded limestone sunk in the ocean, is beautiful scenery. Minamijima Land snails Predatory Submerged Island Land snails Sclerophyllous karst scrub flatworm topography Measures against You black rats must be Land snails accompanied by a guide to land. The predatory flatworm eats land snails. The flatworms, its eggs and other alien species can be spread when they stick to the soles of shoes. To prevent such spread from Chichijima Island, people traveling by the Hahajima Maru boat are asked to wash the soles of their shoes on mats soaked with seawater that are Actions to recover the original placed in front of the passenger waiting area on Chichijima Island and at the ecosystem of Ogasawara disembarking zone on Hahajima Island. Feral goats Wild cats Green anoles Casuarina Black rats In forests, fallen “Mew!” leaves of Casuarina cover Rat the ground and poison prevent other plants from germinating and growing. To restore the forests Fences have been set up around to their original Goats eat rare endemic plants and Higashidaira to protect the Japanese Green anoles live only on Chichijima and condition, trample native vegetation. To eliminate wood-pigeon from attacks by wild cats. Hahajima Islands, where people live. Casuarina trees Black rats eat seabirds, plants, snails, them, fences to separate them have In addition, wild cats are captured Traps are set around the ports to are eliminated by and many other organisms. Rat poison been set up and guns are used as a throughout Chichijima by using basket prevent green anoles from spreading using chemicals that almost does not affect other control method. traps. across to the satellite islands. and others. animals is used to kill them..