For the kids
By Peggy Rismiller
While studying a very specialised aspect of echidna biology during 1988/89, Peggy Rismiller examined the Literature which has accrued on echidna research since white man's first encounter with it in 1792. To her great surprise, she discovered that very little had been recorded about the basic biology and life history of the echidna in its natural habitat. This fact, coupled with her utter fascination with the quiet, inquisitive, solitary living egg-laying mammal, made her decide to commence long-term, in-depth studies on the ecology of the short-beaked echidna.
A scheduled study leave to Germany during 1990 interrupted this work. During this time she came across a unique series of publications by an early German researcher. These were of intrinsic interest not just because they were about her own area of study, the Australian echidna, nor because there was a missing link in early literature, and not because they represented an antiquarian's treasure trove.
Here were the results of an era of science that seems to be fading from our concept of what field biology is all about ...
The first preserved echidna specimen was examined by anatomist George Shaw in 17Y2 and duly classified in the tax-onomic scheme. Various revisions were made on the classification after additional preserved specimens were collected by zealous naturalists and inquisitive colonists in the years that followed. Then. in 1884, a startling discovery was made that shook the biological world. Examination of field captured echidnas by Wilhelm Haacke of the South Australian Museum, and concurrently by William Caldwell in Queensland verified observations passed on from native aboriginal Australians many decades before. The revelations were couched in correct terminology and proclaimed, 'Monotremes oviparous, ovum meroblastic'.
Science had discovered that some mammals lay eggs !
This finding stirred the interest of Dr. Richard Semon of Jena, Germany. In 1891 he set out for two years of field work in the Australian bush where he intended to gather first hand information on monotreme reproduction, as well as study the biology of other native Australian animals. Semon found the Australian bush conditions both strange and totally different from what he had expected. Moreover, his primary study subjects, the echidnas, were very elusive. He therefore employed native aboriginals to capture echidnas for him, and during his two-year study season they brought him a total of four hundred specimens. Semon himself attributes the success of his project to these people, because he never managed to spot a single wild echidna without their aid!
Semon's days were full. Generally, his study animals were not brought in until late in the afternoon or evening. To maximise data from his fresh specimens for measurements, observations, drawings and dissections, he worked through the night. During the day he collected and processed marsupials and lungfish. His scientific routine included the full preservation of all anatomical and histological material that was available to him. He then had to transport all of this baggage out of the bush and joined a ship which took him on to further studies in the Coral Seas and then back to Germany late in 1893.
Once back home, Semon set about the all-too-familiar task of writing up his data. Colleagues all over Europe received preserved specimens from him for specialised analysis and comparison. It is a tribute to his thoroughness and technique that within a decade of his field work, over 1000 journal pages of detailed observations, descriptions and illustrations were published. The specimens he shared with numerous contemporaries generated detailed analyses. Four years after returning to Jena, Semon took a new post in Munich where he hoped he could be more of an inspiration to students. Here, he launched into an entirely new direction and continued what was already a productive career.
References to Semon's "Zoologische Forschungsreisen in Australien" appeared periodically for a few years after publication, then they seem to disappear into obscurity. With time, echidna research shifted back to Australia where scientists continued to look at specialised problems. One hundred and ninety-nine years after the echnida first became known to science and one hundred years after Semon began his methodical anatomical and morphological studies, we still have little scientific data on the life of a wild echidna. Questions posed by Sir Richard Owen, anatomist and founder of the British Natural History Museum, in 1865 about basic echidna reproduction, age of sexual maturity and gestation are still unsatisfactorily answered.
Back to the Present
Returning to Kangaroo Island, South Australia after a nine month absence and inspired by the work of Richard Semon, I commenced anew my research at the Pelican Lagoon Research & Wildlife Centre. Previously I had successfully observed and recorded the mating habits of echidnas in the wild. My new goals aimed not only at answering 126-year-old questions about the echidna reproductive cycle, but examining in detail the life of echidna, from egg to adult and scrutinising the secrets behind the success of this ancient mammal.
Long-term, round-the-clock monitoring of individual animals is extremely costly in terms of man-hours. Semon's expedition was financed by a wealthy entrepreneur of the University of Jena and he was able to hire aboriginal help for his field work. My current echidna ecology project relies greatly on the assistance of volunteers. The international non-profit organisation, EARTHWATCH , co-ordinates volunteers from all walks of life who contribute both time and money towards advancing the knowledge of echidna biology. Additional invaluable aid is also provided by community and Australian Conservation Trust Volunteers (ACTV), as well as private enterprise.
Today. compared to 100 years ago, we are much more circumspect in our methods of collecting animals from the wild. Indeed, the habitats of many species have been so drastically impacted, and population levels are so low, that field collection must he carefully monitored. However, it is interesting to find the works of an early field biologist like Semon which show an extraordinary amount of data collection (complete with weight measurements in milligrams, chemical analysis of non-transportable samples anti meticulous recording of data without the aid of lap top computers and data loggers) and an attitude of unending inquisitiveness and collaboration. It is more than interesting, it is inspiring!
Kangaroo Island -- a Unique Laboratory
The echidna is the most widely-spread native Australian mammal. However, since it leads a cryptic a net solitary lifestyle little is known shout population dynamics or density. The face of Australia has changed immensely in the past 200 years and we have no idea how these changes have affected the echidna populace in different parts of the country. Kangaroo Island offers a field biologist such as myself unique. valuable opportunities. There are still large areas of near pristine land (there are no rabbits on the island), as well as man-altered terrain surrounded by native scrub. The echidna inhabits many types of habitats and seems to have adapted to minor changes in its environment. We have the chance to examine the echidna's interaction with various types of environment here. The island is also free of foxes as an introduced predator. However feral cats do pose a threat. The only known natural predator on the island is the Rosenberg's goanna.
There is still the intriguing question of why so little is known about the basic biology of the echidna in the wild. In fact bottom line inquiry into whole-organism biology of many Australian plants and animals shows a parallel scarcity in concrete and reliable data. We cannot and should not ignore this gap. There is still much basic whole-organism biology to be explored!
Everyone can Help
Time and advances in technology have made much of our present life and research easier and more comfortable. We have tools and equipment to make our work time more productive than it was one hundred years ago. We use radio telemetry tracking to relocate and unintrusively observe our animals in the wild. We monitor micro-and macro-habitat temperatures continuously with data loggers and analysis massive data sets with computers. Despite these advantages, human resources remain irreplaceable and an essential part of field research. On top of this, one must remain in the field -- the natural laboratory of the animal's environment -- in order to resolve its biological mysteries.
Research on Kangaroo Island
Aspects of my echidna research on the island include monitoring daily and seasonal activity patterns, feeding habits and food sources, habitat usage and social interactions The ongoing project involves mark-and-recapture studies on echidnas, in order to determine population densities in different areas, anti to learn about the population dynamics. Since the 1800s, scientists have found a sexual bias in the population of two to three males for every female! Some of our study echidnas have small radio transmitters attached to the spines on their back. This allows us to unintrusively find the echidna on a routine basis and monitor its activities, foraging habits and micro-habit temperatures. Monitoring involves mapping of each individual's movements, mapping vegetation and mapping habitats and types of Food sources. We are also measuring 24 hr temperature profiles in echidna burrows to determine how they change seasonally and what criteria echidna's use for choosing living and nursery burrows. In short, we are initiating long-term research on the echidna's life cycle, in order to understand what it needs in order to continue to survive.
No one has ever followed individual animals long enough in the field to answer basic questions such as 'When is an Echidna sexually mature?' In 1881, George Bennett proposed that the echidna may produce one offspring only every other year. To date no one has proven or refuted his theory. Our long-term studies on the Kangaroo Island echidna will resolve some of these long standing questions. We also have no idea about parent/offspring relationships. For example, what happens to the young after weaning'! Does the mother teach it what to forage for, and where? Must it leave the territory of the parent and explore new grounds? How long does an echidna live in its natural environment? (One echidna lived for 47 years in a zoo in the United States.) Do they increase their population numbers only very slowly because they do live so long and because each animal needs a large area in which to forage and live? When we know the answer to some of these questions, then we may begin to understand how the echidna, one of the oldest living mammals on the earth, has been able to survive in our changing world.
Imagine a Richard Semon today ...
Still, seeing the hundred-year-old work of biologist Richard Semon makes me stop and wonder: What would this person do today? Where would he begin with our resources'! How far would he continue? Where Semon and many other field biologists of his day began was directly in the field. They were often short of equipment and funding (a club that still has a large membership!), but they were strong on perseverence. They were the members of an era known for enthusiasm but often overlooked as to the quality and extent of their contribution. The achievements of these researchers still open avenues to us. Their goals demonstrate standards by which we can measure our tolerances and they give us examples of collaboration that exemplify what can be accomplished. Enjoying the beauty and depth of their work can also give us a chance to refocus on the world around us.
The echidna is classed as 'common because it can still be found throughout Australia. The question is, for how long? Let the echidna be an example of only one of the very many things which we do not thoroughly understand, but take for granted in Our daily lives. Take some time to look and actually observe what you are seeing. Don't be surprised when you discover that the most seemingly banal organism which you encounter is an integral part in the web of life.
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