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Tuatara: Volume 15, Issue 2, July 1967

Guide to Introduced Wallabies in New Zealand

Guide to Introduced Wallabies in New Zealand

Introduction

The Kangaroos, wallabies and pademelons form a very uniform group of about 30 species, restricted to Australia and New Guinea. Considerable confusion exists over the current generic names for subdivisions of this group. As we are not concerned with taxonomic relations within the group, we propose for simplicity to use the wide genus Macropus Shaw as recommended by Ride (1962), although Calaby's (1966) view that the swamp wallaby is sufficiently distinct to warrant a separate genus (Wallabia) seems justified.

Between 1858 and 1870 about 12 species of marsupial were liberated in New Zealand (Wodzicki, 1950) but only the brushtailed opossum (Trichosurus vulpecula Kerr) and the wallabies became successfully established. Because of the very inadequate early accounts of which species were introduced and where they came from, there has been much confusion over the species of wallaby actually present in New Zealand. Hutton (1904) lists only the rock wallaby, Halmaturus sp., (= Petrogale penicillata) and Thomson (1922) apparently considered the wallabies at Waimate and those at Kawau all one species (Macropus ualabatus = M. bicolor). Wodzicki (1950) increased the total to four species and mentioned a fifth.

Wallabies were listed as ‘noxious’ in the Noxious Animals Act, of 1956, and for at least the past twenty years they have been extensively controlled. This situation stressed the need to review page 48 the status and taxonomy of the species present, and led to the rediscovery of M. parma, previously considered extremely rare, if not extinct (Wodzicki and Flux, 1967). Recent collections in all areas where wallabies occur in New Zealand indicate that the following six species are present:

Red-necked or brush wallaby, Macropus rufogrisea (Desmarest) 1817.

Black-tailed or swamp wallaby, M. bicolor (Desmarest) 1804.

Black-striped wallaby, M. dorsalis (Gray) 1837.

Dama or tammar wallaby, M. eugenii (Desmarest) 1817.

White-throated or parma wallaby, M. parma Waterhouse, 1846.

Brush-tailed rock-wallaby, Petrogale penicillata (Griffith, Smith and Pidgeon) 1827.

Australian guides (Le Souef and Burrell, 1926; Troughton, 1946; Marlow, 1962) are too comprehensive or hard to adapt for use in New Zealand, but the present guide should provide a rapid means of identifying any wallaby found in this country.

Key to Species

These brief keys, used in conjunction with Figs. 1 and 2, may be used to distinguish the species found in New Zealand. The characters are amplified in the specific accounts which follow:
Key Based on External Appearance
Tail bushy; uniform diameter to tipPetrogale penicillata
Tail tapering
Under surface rufousMacropus bicolor
Under surface pale, greyish
Dark dorsal and pale hip stripe presentM. dorsalis
Indistinct nuchal stripe, no hip stripe
Shoulder same brownish colour as rest of backM. parma
Shoulder rufous, distinct from greyish back
Tail and hind foot uniformly colouredM. eugenii
Tail and hind foot dark towards tipM. rufogrisea
Key Based on Skulls
First incisor wider than thirdP. penicillata
First incisor narrower than third
First tooth or molar row larger than secondM. bicolor
First tooth of molar row shorter than second
Groove on third incisor 2/3 towards rear of toothM. eugenii
Groove on third incisor more or less central
Rear edge of third incisor curvedM. rufogrisea
Rear edge of third incisor angular
Third incisor groove posterior to mid lineM. parma
Third incisor groove anterior to mid lineM. dorsalis
page 49
Table 1: Average Measurements of Wallabies in New Zealand
Species Sex Number examined Average wt. and range (kg) Measurements in cm. Head and Body Tail Hindfoot Ear
M. rufogrisea M 10 13.2 (6.8-22.7) 65 62 22 9.2
F 12 10.5 (6.8-13.6) 61 62 20 9.4
M. bicolor M 2 12.8 (11.8-13.8) 78 69 23 8.2
F 9 10.3 (5.5-14.5) 67 67 20 8.3
M. dorsalis M 0
F 1 12.7 72 68 22 8.5
M. eugenii M 10 5.5 (2.9-7.6) 53 42 15 7.2
(Rotorua) F 10 4.6 (4.0-5.6) 49 38 14 7.3
M. eugenii M 10 3.6 (2.8-5.4) 46 39 14 7.1
(Kawau) F 11 3.7 (2.7-4.4) 46 39 13 7.0
M. parma M 5 3.8 (3.2-4.5) 49 44 14 6.5
F 11 3.1 (2.5-3.9) 44 42 14 6.5
P. penicillata M 7 4.8 (3.0-5.8) 53 47 14 6.1
F 6 4.3 (2.8-5.6) 52 47 14 6.0

Skull Characters

Skull size is a poor key character because adult wallabies continue to grow for several years. The species in New Zealand, however, fall into two reasonably clear size groups: those with skulls of basal length normally in the range of 80-100 mm (M. parma, M. eugenii, P. penicillata), and larger wallabies with skulls of 100-120 mm basal length (M. dorsalis, M. bicolor, M. rufogrisea). Within each group the names have been arranged in order of increasing average size, but there is a wide overlap between them.

The following characters, most of which are indicated by arrows in Fig 2, are not necessarily unique to the species, but are of value in comparisons. Species likely to be confused are given in brackets.

M. parma (M. eugenii, M. dorsalis): Groove of third incisor central and rear portion of tooth points backwards; edge of premaxilla in contact with nasals approximately twice as long as narrowest width below; posterior edges of nasals meet perpendicularly to the centre line; lachrymal and orbitosphenoid meet, or only narrowly separated by maxilla-frontal contact; molars larger than in eugenii.

M. eugenii (M. parma): Groove of third incisor one third from rear of tooth; front edge of premaxilla convex in side view; nasals widely flared from halfway back, but shape rather variable; parietal ridges do not meet as sagittal crest, and normally remain 5-10 mm. apart; wide zygomatic shelf; zygomatic arch more vertical than in parma.

P. penicillata: First upper incisor wider than third (not clear in Fig. 2 due to plane of drawing); nasals narrowest in middle and page 50 appear ill-fitting with a wide crack down each side; posterior nasal sutures irregularly tongued: depth of muzzle in side view increases towards the front.

M. dorsalis (M. parma): Groove of third incisor towards front half of tooth; posterior edge of nasals indented at midline; nasal narrower than in parma despite larger skull size; two shallow longitudinal grooves on first upper incisor.

M. bicolor (M. rufogrisea): First tooth of upper molar row larger than second; skull looks flattened due to reduced angle of diastema to molar row; reduced zygomatic process of maxilla; smoothly curved nasals.

M. rufogrisea (M. bicolor): Heavy skull; nasals pointed at outer posterior corners; rear edge of third incisor parallels central groove; posterior edges of frontals taper to a point in the midline and do not meet approximately at right angles as in other species.

Accounts of Species

Red-necked or brush wallaby, M. rufogrisea

This species was imported to New Zealand between 1867 and 1870 (Thomson, 1922). One male and two females were liberated on Te Waimate Station about 1874, and these increased to some thousands by 1916 (Studholme, 1954). Their distribution in 1946 is shown in Fig. 3 (inset), slightly modified from Wodzicki (1950). According to the Annual Report of the Rabbit Destruction Council for 1964, wallabies ‘by 1947 had increased to such an alarming extent that some method of control was necessary. From 1947 to 1956 cullers employed by the Wildlife Branch of the Department of Internal Affairs destroyed 68.608. This method of destruction did not even cope with the natural increase of the pest and had the undesirable effect of spreading the animals over a more extensive area’. Following the Noxious Animals Act of 1956 responsibility for wallaby control passed to Forest Service, until the Rabbits Amendment Act of 1959 gave Rabbit Boards power to destroy wallabies, and a special Wallaby Destruction Committee was established at Waimate. Extensive aerial poisoning (Elgie, 1961), followed up by Forest Service shooting, reduced the estimated initial population of 500,000-1,000,000 wallabies on 1,886,000 acres to 3,000-4,000 by 1965, and 2,000 wallabies were killed in 1966 (Annual Reports of the Rabbit Destruction Council, 1964-66). The remaining small pockets of wallabies, from information kindly supplied by the Secretary of the Wallaby Destruction Committee (Fig. 3, inset), appear widely spread; but total numbers are now far lower than in 1946.

A second liberation of this species took place about 1948 (Mr. R. Kean, pers. comm., 1966) at the head of Quartz Creek, on Mount page 51
Fig. 1: The six species of wallaby found in New Zealand. Adult males tend to be more brightly coloured than females or juveniles, and there may be considerable individual variation in colour, specially in M. bicolor.

Fig. 1: The six species of wallaby found in New Zealand. Adult males tend to be more brightly coloured than females or juveniles, and there may be considerable individual variation in colour, specially in M. bicolor.

page 52 Burke Station, between Lakes Hawea and Wanaka. In 1964 about 50 wallabies were seen on a small area on the northwest face of Mount Maude, and the Forks Rabbit Board is attempting to exterminate the colony (Mr. P. T. Brick, pers. comm., 1966).

The red-necked wallaby is one of the larger species found in New Zealand (Table 1) and adult males may reach over 25 kg. It inhabits tussock covered country with scrubby gulleys at 1,000-2,000ft. It is readily distinguished from other species by its clear yellowish-rufous neck and shoulders, long pale grey or fawn fur over most of the body, and black-tipped hind feet and tail (Fig. 1). As it is the only species recorded in the South Island, and does not occur in the North Island, no confusion is possible if the locality is known.

Black-tailed or swamp wallaby, M. bicolor

Thomson's (1922) records of the introduction of this species clearly refer to M. rufogrisea, and it can only be presumed that Sir George Grey was responsible for its liberation on Kawau Island, the only place in New Zealand where it occurs, about 1870.

The black-tailed wallaby, known on Kawau as the ‘wallaroo,’ is easily distinguished from other species on the island by its large size, rich dark colours and tapering dark tail (Fig. 1). One of the males included in Table 1 was a three-year-old captive animal in good condition which weighed 11.8 kg. Le Souef (1929-31) considered that two skins from Kawau belonged to ‘the sub-species apicalis type’ and mentioned that the fur was ‘longer and softer with the overlay of black hairs on the back more marked’ than in Australian skins.

This species occurs over most of Kawau in damp or scrubby areas, but is not abundant compared with M. eugenii and M. parma. Of 59 wallabies seen alive in the southern and central parts of the island by the senior author in May 1966, 49 were M. eugenii or M. parma, 6 were Petrogale penicillata and only 4 were M. bicolor. Similarly, of 118 skulls collected in September 1966, 73 were of M. eugenii, 40 M. parma, 2 Petrogale penicillata and 3 M. bicolor. The faeces tend to be more oblong than in other species of wallaby.

Black-striped wallaby, M. dorsalis

This species was presumably liberated on Kawau Island by Sir George Grey about 1870. Le Souef (1929-31) described the fur of two skins from Kawau as darker and thicker than in Australian specimens, but Dr. W. D. L. Ride (pers. comm., 1958) considered the skins may have been mis-identified. Certainly the specimen in the Auckland Museum (Mamm 47.1) recorded as dorsalis collected on Kawau in 1940 seems mis-identified. The six skulls at Auckland have been re-examined and found to comprise two specimens of M. parma, two M. eugenii, one M. bicolor and one P. penicillata, page 53
Fig. 2: Lateral view of anterior part of skulls, and dorsal view of nasal bones. Useful identification characters are indicated by arrows. For details see text.

Fig. 2: Lateral view of anterior part of skulls, and dorsal view of nasal bones. Useful identification characters are indicated by arrows. For details see text.

page 54 but no dorsalis. Mr E. G. Turbott (in litt., 1947) stated that one skull ‘appears to be a hybrid between Wallabia dorsalis and Thylogale eugenii, or more probably a local modification of T. eugenii’ and this description would fit parma reasonably well.

People living on Kawau do not recognise a description of M. dorsalis, and no skulls were found among 118 collected on a recent visit in September 1966. The only convincing record is of a female with joey poisoned in 1954, identified by Mr. R. Kean, New Zealand Forest Service. Although the skin and skull of this speciment have been lost, and only a photograph remains, the measurements kindly provided by Mr. Kean (Table 1) clearly lie outside the range of M. parma, and there is no other species on Kawau with which dorsalis could be confused.

The black-striped wallaby is now very rare, if not extinct, on Kawau, and does not occur elsewhere in New Zealand. Consequently the colour plate (Fig. 1) is based on Australian descriptions. Ride (1957) suggests that dorsalis in Australia may show geographical variation in coat colour, from pale sandy forms in the north to darker russet brown forms in the south. He also mentions that the pale hip stripe may be faint or absent in dark animals, and this is the colour form one might expect to have developed on Kawau. No hip stripe is shown in Mr Kean's photograph, but there is a prominent dark stripe from the nose to the eye.

Dama or tammar wallaby, M. eugenii

The dama wallaby is found on Kawau Island, where it was presumably introduced by Sir George Grey about 1870, and also on the mainland in the Rotorua area. The origin of the mainland wallabies is obscure. According to Forest Service and Wildlife Branch of the Department of Internal Affairs, they were liberated by the late Mr. H. R. Benn at the southern end of Lake Okareka about 1912, although Mr. W. Pakes of Rotorua, a close friend of Mr Benn, tells us that he never heard of any wallabies being liberated by Mr. Benn. At any rate, by 1930 dama wallabies were well established and provided good shooting (Mr. R. W. S. Cavanagh, pers. comm., 1966). Their range has apparently increased between 1946 and 1966 (Fig. 3, inset) from information kindly supplied by Mr. H. Vipond of Forest Service, and Mr. A. H. Dukeson, Secretary, Pongakawa Rabbit Board, Rotorua.

The dama wallabies at Rotorua are larger on average than those on Kawau (Table 1). The largest male (7.6 kg.) and female (5.6 kg.) from Rotorua are considerably heavier than the largest ones from Kawau (5.4 and 4.3 kg. respectively), although the samples are too small to do more than suggest that different sub-species of eugenii may have been liberated in the two areas. Males tend to be more brightly coloured with more red on the shoulder than females, but there is no obvious difference in colour page 55
Fig. 3: Distribution of introduced wallabies in New Zealand. The species present in each area are: Kawau — M. bicolor, M. dorsalis, M. eugenii, M. parma and P. penicillata; Rangitoto and Motutapu — P. penicillata; Rotorua — M. eugenii; Waimate and Hawea — M. rufogrisea. Stippled areas in insets show the 1946 and 1966 distribution.

Fig. 3: Distribution of introduced wallabies in New Zealand. The species present in each area are: Kawau — M. bicolor, M. dorsalis, M. eugenii, M. parma and P. penicillata; Rangitoto and Motutapu — P. penicillata; Rotorua — M. eugenii; Waimate and Hawea — M. rufogrisea. Stippled areas in insets show the 1946 and 1966 distribution.

page 56 between the Rotorua and Kawau wallabies. In the field their main distinguishing features are their small size, silver grey back and reddish shoulder (Fig. 1).

Around Rotorua dama wallabies are usually found in patches of native bush or scrub from which they emerge at night to feed on nearby paddocks. They make ‘runs’ in the grass as rabbits do, where they can be snared. On Kawau they are the most numerous species present, especially at the southern end of the island and on the central clearings (71 of 86 skulls found) where the vegetation is more open. They are blamed for damage to newly planted pines on Kawau and as many as 3,000 were shot and poisoned in one year by local landowners. Around Rotorua wallabies are controlled chiefly by the Pongakawa Rabbit Board and the Forest Service and many are shot by farmers.

White-throated or parma wallaby, M. parma

The white-throated wallaby is the eastern representative of the eugenii group of small wallabies (Thomas, 1888) and used to be plentiful around Sydney. Troughton (1946) considered that it was probably extinct in Australia and when Ride (1957) reviewed its taxonomy he was able to find only 12 museum specimens in existence. Following a suggestion by Dr. W. D. L. Ride (in litt., 1958) that parma might have been liberated on Kawau, the species has recently been re-discovered there (Wodzicki and Flux, 1967).

As the dama and white-throated wallabies are of similar size and general appearance, and both are common on Kawau, their distinguishing features may be listed in detail. M. eugenii is known locally as the ‘silver grey’ wallaby to distinguish it from M. parma which is called the ‘small brown,’ and this colour difference is the best guide for rapid identification in the field. The reddish shoulder, shorter rat-like tail, and wider, more diffuse pale cheek stripe of eugenii are also useful in separating it from parma (Fig. 1). Most of the parma we observed in the field had a relatively long dark tail with a white or cream coloured tip which was far more conspicuous in live animals than in shot specimens or skins. In the hand, parma may be recognised by a small yellow spot at the notch of the ear, and the shape of the third incisor (Fig. 2).

The white-throated wallaby has been recorded from most parts of Kawau and is more common than the dama on the northern half of the island (25 of 31 skulls found) which is covered with thick scrub (mainly Leptospermum ericoides with a little L. scoparium). They spend the days in thick scrub, and several were seen feeding in the evenings in gardens of cottages at Vivian Bay on the north coast. Since the area of scrub has increased in recent years (Mr. R. Kean, pers. comm., 1966) it seems likely that parma has increased in numbers at the expense of M. eugenii; and, page 57 following the extensive control of wallabies (mainly eugenii) in the plantations at the south of Kawau, parma could become the commonest species on the island.

Brush-tailed rock-wallaby, Petrogale penicillata

Thomson (1922) records that the Auckland Acclimatisation Society received a rock wallaby ‘Petrogale xanthopus?’ from Sir James Fergusson in 1873, but that there was no later report of it, and that Mr. John Reid liberated small brown rock wallabies on Motutapu. From there they spread across a narrow neck of land to the adjoining Rangitoto Island, and were recorded as numerous by 1912. A second introduction may have been made by Sir George Grey, as the species occurs also on Kawau.

This is the most brightly coloured of the wallabies found in New Zealand and its bushy tail readily distinguishes it from all other species (Fig. 1). Le Souef (1929-31) found that two skins from Kawau had darker, more silky fur than Australian specimens, with all markings more contrasted and the buttocks a brighter foxy-red than usual. As the skins tend to fade very rapidly however, one wonders whether the comparison was made with fresh Australian material or not.

Rock-wallabies are very agile and can climb as high as 12ft. on sloping trees, but feed mainly on grassy clearings above the cliffs. They appear to be most numerous on Motutapu, where 517 were shot in 1965 by Forest Service for Lands and Survey Department. On Kawau they seem scarce but occur wherever there are cliffs: in May 1966 six were seen in a total of 59 wallabies identified, and in September 1966 none were seen and only two of 118 skulls found were of rock-wallables. Rangitoto is mostly recent scoria, with a fragmentary vegetation (Millener, 1953), so that the rock-wallabies are not restricted to cliffs but occur in small numbers all over the island, congregating only at refuse dumps in search of scraps. Between 1948 and 1950 several hundred were trapped on Rangitoto, mainly for skins.

Discussion

Of the 12 species of wallabies introduced into New Zealand almost 100 years ago, six became established, although one of these is now very rare. The two species on the mainland have not spread far from their original points of liberation.

With the realisation of the extent of competition for grazing and of damage by introduced mammals, the pendulum of public opinion swung from acclimatisation to extermination. Animals had been introduced without carefully considering the species involved or how they would adapt to or modify their new environment, and extermination attempts were begun in the same unscientific way. page 58 Under the Noxious Animals Act of 1956 ‘Wallabies (family Macropodidae)’ are indiscriminately proscribed; and as recently as 1962 the Rabbit Destruction Council's annual report, writing of Kawau Island, states: ‘It is, however, a pity that a vigorous campaign of destruction is not waged against wallabies wherever they are, in an endeavour to eliminate this pest from the country entirely’. Had this been done the world would have lost the parma wallaby, a species of almost as much interest in Australia as the takahe in New Zealand; and this emphasises the need for a more tolerant approach to the introduced animals which have become part of the New Zealand environment.

Very little is known about the wallabies in New Zealand, despite the extremely favourable conditions for study here compared with Australia. Even the list of species present may not yet be complete, as there are rumours of a second species in the Rotorua area and of a mainland colony of rock-wallabies in Northland, which we have been unable to verify. It is hoped that this guide will stimula interest in a neglected group.

Summary

Six species of wallaby introduced into New Zealand from Australia about 100 years ago have become established. These are the red-necked wallaby (Macropus rufogrisea) in South Canterbury and near Lake Hawea; the black-tailed (M. bicolor) and black-striped (M. dorsalis) wallabies on Kawau Island; the dama wallaby (M. eugenii) on Kawau and around Rotorua; the white-throated wallaby (M. parma) on Kawau; and the brush-tailed rock-wallaby (Petrogale penicillata) on Kawau, Rangitoto and Motutapu Islands. A key is provided for their identification.

Acknowledgements

We are grateful to Messrs P. T. Brick, R. L. Edgar, J. H. Gillespie, J. Haigh, T. W. Lees, J. Montgomerie, C. A. Scott, Mr and Mrs S. T. Sowerby, A. H. Taylor, and P. R. Wilson for their help in collecting specimens. Mr. R. Kean of Forest Service kindly allowed us to use his unpublished weights and measurement of 50 wallabies, which added greatly to the value of Table 1, and he, Dr. J. A. Gibb and Mr. R. H. Taylor made many useful suggestions on the text.

References

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Elgie, H. J., 1961. Wallaby eradication by aerial poisoning. N.Z. Jl. Agric., 102, 25-31.

Hutton, F. W., 1904. Index faunae Novae Zealandiae. Dulau, London. 372 pp.

Le Souef, A. S., 1929-31. Occasional notes, 2. Alteration in character of wallabies acclimatized on Kawau Island, New Zealand. Australian Zoologist, 6, 110-111.

Le Souef, A. S. and Burrell, H., 1926. The wild animals of Australasia. Harrap, London. 388 pp.

Marlow, B. J., 1962. Marsupials of Australia. Jacaranda Press, Brisbane. 141 pp.

Millener, L. H., 1953. How old is the vegetation on Rangitoto Island? Proc. N.Z. Ecol. Soc., 1, 17-18.

Ride, W. D. L., 1957. Protemnodon parma (Waterhouse) and the classification of related wallabies (Protemnodon, Thylogale, and Setonix). Proc. Zool. Soc. Lond., 128, 327-346.

Ride, W. D. L., 1962. On the use of generic names for kangaroos and wallabies (Sub-family Macropodinae). Aust. J. Sci., 24, 367-372.

Studholme, E. C., 1954. Te Waimate. Early station life in New Zealand. Reed Wellington. 310 pp.

Thomas, O., 1888. Catalogue of the Marsupialia and Monotremata in the collection of the British Museum (Natural History). British Museum, London. 401 pp.

Thomson, G. M., 1922. The naturalisation of animals and plants in New Zealand. Cambridge Univ. Press. 607 pp.

Troughton, E., 1946. Furred animals of Australia. Angus and Robertson, London. 376 pp.

Wodzicki, K. A., 1950. Introduced mammals of New Zealand. N.Z. Dep. Sci. Industr. Res. Bull., 98. 255 pp.

Wodzicki, K. and Flux, J. E. C., 1967. Re-discovery of the white-throated wallaby, Macropus parma Waterhouse 1846, on Kawau Island, New Zealand. Aust. J. Sci., 29 (11), 429-430.