The Dibbler Story

After 83 Years "Extinct": the Dibbler Rediscovered!

In the summer of 1967, naturalist-author Michael Morcombe was trying to find a Honey Possum, a tiny mammal which feeds upon the nectar of flowering shrubs. Instead, another was discovered, one which had not been seen, except in museums, for 83 years. This was the Dibbler, then considered to be extinct, like many other small Australian animals unable to survive loss of habitat, and the predations of feral cats and foxes .

Found only in the south-west of Western Australia, the Dibbler was rediscovered after a very long period during which there had been no sightings, nor any sign that any of these small carnivores still existed. The Dibbler (Antechinus apicalis) is a species of marsupial, as are so many other Australian furred animals, including the kangaroos, Koala, and many carnivores from wolf-sized Thylacine down to various mouse-sized hunters of insects.

Many of these creatures that populated Australia have become extinct, through loss of habitat, as prey of introduced cats and foxes, or competition with a whole range if introduced feral animals. Much of the Dibbler's range, from which a small number of individuals was taken prior to 1884, was cleared for farming early in the European occupation of Western Australia. Most remaining areas, too rugged or with soil too poor for farming, have been swept by bush fires, from which the vegetation gradually recovers, but often not their populations of small animals.

The Dibbler was rediscovered in 1967, at a location close to the south coast of Western Australia, where the sandy hilly country had been left uncleared. Naturalist/author Michael Morcombe was at that time researching and gathering illustrations for a book of the wildflowers of Western Australia (Australia's Western Wildflowers) and wanted to include a chapter on the pollination of these wildflowers by birds and mammals... so different from the insect pollination of flowers that is usual for much of the northern hemisphere (see Story of Pollination)

In searching for a mouse-sized marsupial known as the Honey Possum, he found instead a slightly larger creature, which he recognized as the long-lost Dibbler, over the past 83 years, and considered to have become extinct. The full story of this marsupial the Western Australian Naturalist, Vol 10, Number 5, of May 16, 1967, which is reprinted here. Dibbler Update

Below: The rediscovery as reported in "The Western Australian Naturalist" of May, 1967
 

Dibbler feeding on insect, while on yellow flower of Banksia attenuata
Colour photo from The Western Australian Naturalist, May 16,1967


THE WESTERN AUSTRALIAN

NATURALIST
Vol. 10 May 16, 1967 No 5


THE REDISCOVERY AFTER 83 YEARS OF THE DIBBLER ANTECHINUS APICALIS (MARSUPIALIA, DASYURIDAE)

BY M. K. MORcoMBE, Armadale, W.A.



INTRODUCTION


The carnivorous marsupial Antechinus apicalis (Grey, 1842) has not been collected for at least 83 years and consequently has been considered possibly extinct (Glauert, 1933). Quite apart from its rarity it is also a species of scientific interest because of disagreement about its classification: Tate (1947) erected a monotypic genus, Parantechinus,for this species, based on the extreme reduction of the posterior premolars which are single-rooted vestiges. Ride (1964) in describing a new dasyurid species A. rosamondae, with even more extreme premolar reduction, has commented on the taxonomy of Antechinus, Parantechinus, and Pseudantechinus and suggests a return to the wider concept of Antechinus for all species of this group.

I obtained two specimens of Antechinus near Cheyne Beach, 30 miles east of Albany, Western Australia, by trapping on the flowers of Banksia attenuata. The first, a female, was caught on the night of January 26, 1967, and this specimen, with a male caught two nights later, has been kept alive to the time of writing (30 March) for observations on behavior.

 

REDISCOVERY


Between January 12 and 13, 1967, trapping was carried out in the Albany district, and eastwards, with the primary objective of collecting a live specimen of the Honey Possum, Tarsipes, which is well known to be associated with Banksia and other large wildflowers.

Traps were made, to fit over these flowers. Several versions of trap were made, and the most satisfactory seems to be a cylinder of fly wire stiffened with a medium thickness fencing wire. ONE END IS CLOSED PERMANENTLY, THE OTHER BY A circular door, which is hinged. A mousetrap wired to the outside of the cylinder pulls this door shut, the tripwire passing from this mousetrap through the centre of the cylinder and being tied to the opposite side. The construction is simple, the cost very low, and a dozen can be made in a few days.

The setting of these traps on flowers is not as conveniently done as the setting of conventional box traps on the ground: a flower with a straight, upright stem is needed. The cylinder, over the flower, must be wired to the stem below the flower, and usually braced with wires to nearby branches. Leaves must be removed where they would interfere with the upward swing of the door. The tight fit of the door around the stem is usually a problem. The door must have a notch to fit the branch, and though the cages may be made to a pattern, Banksia branches are not, and it is usually necessary to bend and shape the cage and its door a little to fit each branch. The tripwire passes over the surface of the flower.

Until January 22 these traps, up to ten in number, were set on flowers of Banksia attenuata and BANKSIA GRANDIS SCATTERED THROUGH A DENSE THICKET OF Banksia coccinea near Oyster Harbour, Albany. However, two small mammals were seen here: one in the talons of a low-flying Brown Hawk, Falco berigora, and the other running through low vegetation- the impression gained was of a rat rather than a marsupial.

All the traps were shifted, next, to a site between Cheyne Beach and Lookout Point on January 25 between 50 and 100 yards from the fishing settlement, and again set on B. attenuata flowers. On the morning of the 26th the sole occupant of the traps was a Rattus fuscipes, caught on a flower five feet above ground. However on the morning of January 27 a trap set perhaps two feet above ground held a small marsupial, a female of Antechinus apicalis.


The vegetation here consisted of stunted Banksia attenuata to a height of about six feet; dense clumps of B. baxteri to eight or ten feet; extensive clumps of the Peppermint, Agonis, and dense undergrowth of low tangled scrub to perhaps two feet.

On the morning of January 29 a trap on a flower four feet above ground held a second, larger Antechinus apicalis, a male. A nearby trap contained another specimen of Rattus fuscipes. The trapping was then discontinued.

 

PREVIOUS BIOLOGICAL STUDY OF THE CHEYNE BEACH AREA


The area around Cheyne Beach and Mt. manypeaks is little known zoologically. In 1959 a party from the Zoology Department of the University of Western Australia spent a week exploring the countryside around Cheyne Beach prior to crossing to nearby Bald Island to collect live Quokkas and to study the flora and fauna (Storr 1965). Mammals and birds of the areas east, west and inland of Cheyne Beach were recorded. Among the mammals,
Rattus fuscipes was plentiful in the sandplain near Cheyne Beach and three were caught in box traps placed on the ground at the entrances of burrows (G. M. Storr pers.comm..) Antechinus apicalis was not collected. nor were bones of this species among others collected in a cave near Waychinicup Estuary.



PREVIOUS RECORDS OF LOCALITY
 

(1) From museum specimens.

The British Museum (Natural History) has several specimens (see Thomas, 1888: 278). All but one of these were registered in the 1840s, and almost came from Goulds collector, Gilbert; these two specimens, which may be from the same individual (a skin 4 7.1.27.2 and a skull 48.1.27.2) are from a precise locality, i.e. Victoria Plains,* Western Australia. The other (No 86.9.1.1) was registered in 1866 and was purchased from Gerrard who gave Albany as the locality (Ride, pers. comm.)

City of Liverpool Museum. A specimen No. 272a, J. Gould Collection: original collector's label still attached, "July 3, 1843 Vicinity of Moore R. Western Australia."

Rijkmuseum v. nat. Hist. Leyden: two specimens, one purchased in 1844, with Moore's River as locality; the other with no data or precise locality (Jentink, 1888).

The Australian Museum, Sydney has one specimen (No 601) collected in ?1869 at the Salt River, W.A. (i.e. the Pallinup R. about 60 miles east of Albany). This is probably the specimen collected by Masters in 1869 (see list in Glauert, 1950:126).

The National Museum, Victoria has no specimens with precise locality, but there are 22 in all from Western Australia probably taken between 1875 and 1884.

The Queensland Museum has two juvenile specimens recorded by Thomas (1888: 278) which De Vis says are from Rockhampton, Queensland. Ride (
pers. comm.) agrees with Thomas's (p.278 footnote) that these cannot be separated from A. apicalis on their morphology; although Ride has some reservations because he has not compared them with other juveniles of A. apicalis.

(2) From Literature

Gilbert's notebook on the marsupials (Whittell, 1954) includes entries in his own handwriting, on species he had collected, and there is an entry (giving native names) for three localities for this species:

"Antechinus
Marn-dern, Aborigines of Moore's River
Wy-a-lung, Aborigines of Perth
Dib-bler, Aborigines of King George's Sound "**
and "Hab: Western Australia. No 2 of my collection."

His only notebook specimen mentioned with locality, was from Albany: "While at the Sound I obtained a female with seven young attached in the same manner as observed in
A. leucogaster."

Gould also in the introduction to The Mammals of Australia (1963) says:

"Mr George French Angas having sent me a skin of this animal from South Australia, I am enabled to state that its range extends from Western Australia to that colony." Ride (pers comm.) has been unable to trace that specimen, and the species is not mentioned by Wood Jones (1923) in
The Mammals of South Australia.

(3) Fossil Records

Lundelius (1957) has added to collectors' information on locality for a number of animals including Antechinus apicalis. He considers the fossil assemblage of the top foot and surface in caves along the west and south coasts of W.A. "to represent the fauna of these areas before the effect of introduced species was felt." He recorded Antechinus apicalis "in caves along the west coast from Yanchep to Jurien Bay. It appears to have occupied a strip of country along the coast as far south as Yanchep, then inland to Albany, skirting the high rainfall area of the south-west corner. No remains are known from the Margaret River caves."

Lundelius (1957) records
A. apicalis near Jurien Bay, from Drovers Cave, four miles inland from the Bay and 130 miles north of Perth, in deposits to a depth of five feet; and from Wedge Cave one mile north-west of Mimegarra homestead, 100 miles north of Perth, to a depth of 81/2 feet in the deposits.

The species was not recorded from the Mammoth or Nannup caves, both near Witchcliffe in the extreme south-west of Western Australia, nor was it among fossils from six caves located on the southern edge of the Nullarbor Plain (
Lundelius, 1963).

PREVIOUS RECORDS OF BEHAVIOR AND ECOLOGY

There are very few records of the behavior and ecology of Antechinus apicalis, so those known are quoted in full.

(1) From Gilbert's Notebook (Whittell, 1954)

"This species is universally dispersed over the whole of Western Australia: it is easily distinguished from all others of the Genus by the long hairs on the sides of the basal portion of the tail giving the tail a pointed appearance. It appears to vary a good deal in habits in different localities. At Moore's River the natives describe it as making a nest beneath the overhanging grasses of
Xanthorrhoea. While at Perth its nest is taken either from the dead stump or from the upper grasses of the same plant, while at the Sound the natives constantly pointed out a nest of short pieces of sticks and grasses on the ground very much resembling the common Perameles except that there was a much larger and higher heap than is generally brought together by the latter. On examining the stomach it was found to contain insects generally, but more particularly small Coleoptera. While at the Sound I obtained a female with seven young attached in the same manner as observed in A. leucogaster. These young were little more than half an inch in length, the hinder parts remarkably small, as compared with the anterior extremities. The young are very tenacious of life in the above instance the young lived attached to the body of the mother for nearly two days before I put them in spirits, and it was nearly two hours after immersion that they stopped moving.
Hab: Western Australia. No. 2 of my collection."

(2) From Gilbert's letter to Gould from Perth, March 27, 1843 (in Wagstaff and Rutherford, 1955).

"It was brought to me by a native, who said he had captured it in a nest formed in a slight hollow in the ground , and under the shelter of a
Xanthorrhoea. My specimen is a female: its mammae were four in number, and bore the appearance of having had as many young ones attached which were probably torn off by the Native in catching it. J. Drummond informs me that the Male is much larger. He has a specimen which he has promised me."

OBSERVATIONS OF THE ECOLOGY AND BEHAVIOR OF ANTECHINUS APICALIS

(1) In the Wild

The capture of two specimens of this species, both on banksia flowers, suggests some dependence upon the larger wildflowers so common on these coastal sandplains, for nectar and for insects. (Night examination of these banksia flowers revealed copious nectar, and insect life far more abundant than by day; great numbers of minute insects, crickets, spiders, several olive-green centipedes, and on one flower, a sleeping Southern Emu-wren ( Stipiturus malachurus, which was easily caught by hand).

It seems that the banksias not only provide water as nectar (for which they are visited also by the Honey Possum and
Rattus fuscipes) which in turn would be an added attraction for ant small carnivorous marsupial such as Antechinus apicalis.

Conversely it is suggested that the very small insects that are present in great numbers within the tangled mass of banksia flowers, well below the sites of pollen transfer, could but rarely pollinate these flowers, but serve well as an added attraction for honey eating birds and for the small marsupials whose probing of the flowers must be equally effective in pollination.

The site of capture suggests Apichinus
apicalis is partly arboreal. Observations of behavior in captivity support this.

(2) In Captivity

To the time of writing, the two specimens of Antechinus apicalis have been kept in captivity for six weeks on a diet of various insects (predominantly grasshoppers) and spiders and raw meat. Milk and water were taken; both seemed more acceptable if honey was added. Fresh banksia flowers placed in the cage were probed and licked with great enthusiasm.

This Antechinus can climb quickly and surely, and is fast along branches and among foliage, and commonly springs from branch to branch a foot or more. Occasionally, if suddenly disturbed, it will release its grip and drop three feet from the top of its cage, landing with a thud but immediately pushing beneath the loose leaf litter. When both rush around the cage in the evening or in the early hours of the morning these jumps and drops are common, almost constant, at the peak if their activity.

A. apicalis grasps slender branches or twigs by separating the thumb and first digit from the other three and holding the stem between them. On larger stems or trunks such as Banksia the animals appear to gain sufficient traction through their claws and foot surfaces.

The tail serves as a balance and prop when climbing vertically or clinging to the rough-textured surface of a banksia flower. The long, stiff, rather harsh fur at the base of the tail is pressed hard against the flower, particularly when the Dibbler has caught an insect and, as is customary, holds it in its hands to eat. Often as the animals descend they curve the tail laterally to press it against twigs and stiff leaves, and this seems to stabilize their swift descents.

Fresh flowers of Banksia placed in their cage are immediately investigated: the Dibblers probe and lick among the rows of tiny massed flowers, giving the impression that they are very familiar with these flowers and their nectar or insect content.

Insects, when first offered are grabbed in the forepaws and held while eaten, the first bites being always directed at the head. Large spiders and potentially dangerous prey are not immediately grasped, but are dealt several quick, buffeting blows before being snatched up again, given another quick bite or two, dropped again, and then eaten or further disabled. The whole action would occupy perhaps one second.

In captivity this marsupial is not entirely nocturnal. It is most active early in the morning, but the leaps and the running slow down as th sunlight's warmth and glare increases, until by ten or eleven both Dibblers have pushed beneath the loose leaves thick on the floor of the cage, where they sleep until near sunset. Again they are very active until nine or ten p.m., then seem to sleep much of the night (becoming active if lights are turned on for a while) but are always dashing around their cage by 5a.m. as the sky lightens with approaching dawn.

On one occasion the male was sunning himself when sunlight reached into one corner of the cage. This habit may be more frequent in winter or in the much cooler summer days of the south coast.

A. apicalis in captivity seeks shelter and moves about under loose leaf litter where this lies thickest on the ground; in bright light the animals will not climb, but they will move around on top of the litter, the slightest disturbance sends them beneath the litter in which they burrow by forcing themselves through with considerable violence to emerge at some other point. By continuous use of the one hiding place , something of a ckamber is formed among the mass of leaves and fine twigs; paper twigs have also been shredded and incorporated into the wallsand the entrance remains open. It is probable that the activity concentrated in the nesting area would also result in a slight hollow in loose soil; probably by continued usage and burrowing under the mass of litter. Such a hiding place could well fit the description of a nest given in Gilbert's letter to Gould.