The Spectacular Sea Anemone 438 by U
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THE AUSTRAL IAN MUSEUM will be 150 years old in March 1977. TAMS has its 5th birthday at the same time. Like all healthy five year olds, TAMS is full of fun, eager to learn about the world and constantly on the go! 1977 is a celebration year. Members enjoy a full and varied programme, are entitled to a discount at the Museum bookshop and have reciprocal rights with many other Societies in Australia and overseas. Join the Society today. THE AUSTRALIAN MUSEUM SOCIETY 6-8 College Street, Sydney 2000 Telephone: 33-5525 from 1st February, 1977 AUSTRAliAN NATURAl HISTORY DECEMBER 1976 VOLUME 18 NUMBER 12 PUBLISHED QUARTERLY BY THE AUSTRALIAN MUSEUM, 6-8 COLLEGE STREET, SYDNEY PRESIDENT, MICHAEL PITMAN DIRECTOR, DESMOND GRIFFIN A SATELLITE VIEW OF AUSTRALIA 422 BY J.F . HUNTINGTON A MOST SUCCESSFUL INVASION 428 THE DIVERSITY OF AUSTRALIA'S SKINKS BY ALLEN E. GREER BOTANAVITI 434 TH E ELUSIVE FIJIAN FROGS BY JOHN C. PERNETTA AND BARRY GOLDMAN THE SPECTACULAR SEA ANEMONE 438 BY U. ERICH FRIESE PEOPLE, PIGS AND PUNISHMENT 444 BY O.K . FElL COVER: The sea anemone, Adamsia pal/iata, lives ·com IN REVIEW mensally with the hermit crab, Pagurus prideauxi. (Photo: AUSTRALIAN BIRDS AND OTHER ANIMALS 448 U. E. Friese) A nnual Subscriptio n : $4 .50-Australia; $A5-Papua New Guinea; $A6-other E DITOR/DESIGNE R countr ies. Single copies : $1 ($1.40 posted Australia); $A 1.45-Papua New NANCY SMITH Guinea; $A 1.70-other countries. Cheque or money order p ayable to The ASSISTANT EDITOR Australian Museum should be sent to The Secretary, The Australian Museum, ROBERT STEWART PO Box A285, Sydney South 2000. Overseas subscribers please note that PRODUCTION ASSISTANT monies must be paid in Australian currency. LEAH RY AN C IRC ULATION New Zealand Annual Subscription: $N Z6.25. Cheque or m oney order payable MARIE-ANNICK LEHEN to the Government Printer should be sent to the New Zealand Government EDITORIAL COMMITTEE Printer, Private Bag, Wellington. HAROLD COGGER KINGSLEY GREGG Opinions expressed by the authors are their own and do not necessarily represent PATRICIA McDONALD the policies or views of The Australian Museum. RONALD STRAHAN IN T[I'I~A TI ONA I.. "TA "'O A RO S f;R >AL N VM EIE ~;t 0 004·9140 421 422 AUSTRALIA N NATURAL HISTORY A SATELLITE VIEW OF THE AUSTRALIAN ENVIRONMENT BY JON HUNTINGTON ince late 1972, our knowledge of factors influ to have been out of position by 3.2km on published S encing terrestrial and near-shore environments maps. In Australia, satellite-i ndicated shapes and sizes and our means of surveying natural resources have of some off-shore reefs differ from those on published benefited from information from an important new maps. Elsewhere, the satellites have provided valuable source. This source is a family of experimental, Earth information on crop production, tree diseases and orbiting satellites, some of which are capable of photo illegal gravel dredging at sea, as well as regional views of graphing the entire Earth's surface every 18 days, and geological structures and other natural resources. others which can resolve detail as small as 30 metres. Satellite pictures showing patterns of effluent discharge The first of the present family of Earth Resources in Lake Champlain in Vermont have been accepted as Technology Satellites (EATS) was launched by NASA evidence in the Supreme Court in the USA. on July 23, 1972 and was designed specifically to Whilst the LANDSAT data are available to virtually examine the value of satellite data for efficient manage anyone for any part of the world, several Australian ment of the Earth's resources. (On January 13, 1975 investigators have collaborated with NASA in studying the Earth Resources Technology Satellite was officially the potential usefulness of the LANDSAT data in renamed LANDSAT.) Earth photography from space, agriculture, land use, forestry, geology, water resources, of course, is not new, and dates back to 1946. This was oceanography, geography and the study of natural the first time, however, that the Earth's resources were disasters. In addition, growing numbers of people are to be examined systematically, using technology incorporating the use of the data into their day-to-day largely developed for the lunar space programme. operations. The quality and potential value of the The value of the current satellite photography photography returned by this satellite led NASA to stems from the following attributes: launch a second, identical satellite on January 21, -the large area or regional view obtained of the 1975, nine days out of phase with the first. Though Earth's surface under relatively uniform conditions. both sateII ites are still in operation, photography Each picture covers 185x185km of the Earth's of Australia all but ceased in late 1975 due to diffi· surface. culties with the systems required for recording infor· -the repetitive coverage of the entire Earth's sur mation for later transmission in the absence of an face every 18 days, (weather permitting). The Australian ground tracking station. Between July dynamic nature of our environment ·means that con 1972 and July 1975 the two satellites acquired some tinuing sensing is of great value in recording changes in 212,252 photographs of Earth, equivalent to total land use patterns, seasonal differences in vegetat ion world coverage 14 times over. communities and ephemeral events such as fires and The LANDSATs orbit the Earth every 103 minutes floods. passing across Australia, from north to south, at an -the use of multispectral sensors; that is, the divi altitude of 907km. Their orbits are sun-synchronous sion of the energy reflected f rom the Earth's surface and cross the equator each day at 0942 local time, into a number of discrete wave-length bands, equival progressing across the globe from east t o west. This ent to the green, red and two infrared portions of the means that each point on the Earth is photographed spectrum. These provide four pieces of information at approximately the same time of day and under about each point on the ground instead of the single similar conditions of solar illumination, limiting the piece normally available from conventional aerial Colour major differences visible in the photography to photography. Such a division provides a greater chance enhancement of environmental and seasonal changes only. of reliably discriminating between different terrain subsurface water detail, sand banks, The resolution and cartographic accuracy of t hese features. The satellite also sense reflected energy in and submerged reefs, sateII ite photographs have been particularly useful in beyond the range of standard photographic films and current patterns and surveying the many inaccessible and still unmapped islands in the Torres well beyond the sensitivity of the human eye. Strait between Cape parts of the world. New lakes and rivers have been Since the sensors carried by the LANDSAT are not York and Saibai Island off Papua discovered in Brazil and a Fijian island is reported conventional cameras, the pictures produced are New Guinea. ~~~~~~~~~~~~~~~~~~~==~~~~~~~~~~~~~~~~~~~~~~~~~--- Skewedshapeisdue JON HUNTINGTON is a research Scientist with the CSIRO Division of Mineral Physics at North Ryde, NSW. Previously a photo- to earth rotation geologist in private industry, he is now engaged in researc h into the value of LANDSAT data in geology. He is Chairman of the during passage of Remote Sensing Association of Australia. the satellit e. V0LUME18NUMBER12 423 approxi mate those of a conventional colour infrared photograph. On each of the multispectral images, particular terrain materials (rocks, soils, vegetation, buildings) will appear a different tone, according to the reflec t ive properties of those materials. For example, healthy deciduous vegetation is highly reflective in t he infrared and appears much lighter in tone on infrared images than on red images. The difference for evergreen, dry sclerophyll forest is not quite so strong. Further, whilst all water is totally non-reflective(i.e. black) on infrared images, muddy, sediment-filled water can be highly reflective on green spectrum images. The amount of detail visible on a LANDSAT image is largely determined by the contrast between the objects being sensed and the 78x78 metre ground resolution of the sensors. Each image is made up of some 7.5 million of these overlapping 78x78 metre areas, or over 30 million per four-image scene. Trans lation of this information from magnetic tape t o photographic film inevitably leads to a degradation of the information, whilst the type and number of photo graphic steps involved can reduce the quality and value of the images even further. Research in the CSI RO Division of Mineral Physics has largely overcome these problems by returning to An enhanced referred to as images rather than photographs. As the the original digital data and creating, via computer LANDSAT view satellites orbit, the sensors simultaneously record of the regional processing, the best possible image for each investi geology of the east four, filtered, black and white images, each in one of gator's problem. This research has also ill ustrated Pilbara between Marble Bar and the parts of the spectrum mentioned above. These t hat, whilst analysis of the satellite data on film Nullagine, Western four images, each covering the same 34,225sq. km of remains the si mplest and most economic method, Australia. Inter relationships of ground, go to make up one scene of the Earth's sur computer processing tec hniqu~s are essential if we are many important face. Some 402 such scenes are needed to completely to take full advantage of all the data collected by these rock units and geological structures cover the Australian continent. sate II ites. are shown in this The image data sensed by the satellite are available Agricultural problems being investigated in Australia active exploration and overseas involve the suitability of the satellite area.