The respondent Minister made declarations under the Environment Protection and Biodiversity Conservation Act 1999 (Cth) that particular plans relating to Bennett's wallabies and Tasmanian pademelons were approved wildlife trade management plans. The applicant questioned whether the plans permitted the inhumane hunting of wallabies and treatment of joeys as well as the basis upon which the quotas were derived. The tribunal found both matters satisfactorily addressed though further monitoring measures were deemed to be prudent.
1. On 30 November 2005 the respondent, the Minister for the Environment and Heritage, made declarations pursuant to s 303FO(2) of the Environment Protection and Biodiversity Conservation Act 1999 (Cth) (the Act) that the:
• Wildlife Trade Management Plan for the Commercial Harvest of Bennett’s wallabies and Tasmanian pademelons on Flinders Island, Tasmania 2005 to 2010; and,
• Wildlife Trade Management Plan for the Commercial Harvest of Bennett’s wallabies on King Island, Tasmania 2005 to 2010;
were approved wildlife trade management plans for the purposes of s 303FO of the Act. The program will apply from 1 July 2005 to 30 June 2010.
2. A copy of the Minister’s decision was published in the Gazette on 14 December 2005 as required by s 303FO(2) of the Act.
3. On 12 December 2005 the applicant, the Wildlife Protection Association of Australia Inc., lodged an application to review the respondent’s decision to approve the management plans. Subsequently the Australian Wildlife Protection Council Inc., Animals Australia and Flinders Council were joined as parties to the proceedings. Those parties, other than Flinders Council, supported the arguments of the applicant. Flinders Council did not participate in the hearing. For simplicity, references hereafter to the applicant are intended to encompass the joined parties that supported the applicant as well as the applicant.
4. It is, we think, important to stress at the outset that the Minister’s decision, and our decision, are not decisions that authorize the commercial harvesting of Bennett’s wallabies and Tasmanian pademelons per se, rather the decisions seek to impose a framework to that commercial harvesting in the context of the Commonwealth’s powers in relation to the export of the products from those animals to overseas markets. Except within that context, it is not within the power of the Commonwealth to impose restrictions on the harvesting of the animals.
5. Absent the management plans, the harvesting of the animals would continue, subject to the controls imposed by the Nature Conservation Act 2002 (Tas.) and the Wildlife Regulations 1999 (Tas.) made under that Act.
4. What follows seems not to be contentious. Much of it is taken from the background information contained in the two management plans. Mr Hocking, a zoologist employed by the Tasmanian Government in the Department of Primary Industries, Water and Environment, was the principal author of the management plans and swore to the correctness of the background information contained in it.
5. Flinders Island is north east of Tasmania in the Bass Strait. It is about 64 kilometres long by up to 29 kilometres wide with an area of 1,340 square kilometres.
6. Economic activity on the island centres mainly on beef cattle, fat lambs, wool, fishing and dairying.
7. The island’s population is about 900. The town of Whitemark is located on the west coast and the town of Lady Barron on the south coast. A large number of the population live on rural properties.
8. Approximately 73,000 ha of land on the island is privately owned and is used for primary production and another 2,000 ha is State Forest. Together, this represents 58 per cent of the area of Flinders Island. The remaining 42 per cent of the island includes 38,000 ha of unoccupied Crown Land and 17,000 ha of conservation reserves. The largest of the reserves, the Wingaroo Nature Reserve, has an area of 9,144 ha. Strzelecki National Park has an area of 4,215 ha.
9. A wide range of habitats suitable for both Bennett’s wallaby and Tasmanian pademelon is represented in these reserves as well as the unoccupied Crown Lands. No hunting of wallabies is permitted on reserve or Crown land. In addition there are numerous small reserves that provide sanctuary for the wallabies.
10. The terrain of Flinders Island is hilly, although not as hilly as the rest of Tasmania.
11. The island has a fairly even distribution of roads except for the reserves and Crown Land. Most of the roads are covered in white quartz gravel and have relatively narrow verges of about two metres either side of the road. Unpalatable native vegetation grows on these margins.
12. King Island, north west of Tasmania, is 64 kilometres long and 27 kilometres wide, with an area of 1,094 square kilometres.
13. Economic activity on the island centres on tourism, kelp processing, beef cattle, dairy, crayfish and oyster farming.
14. The island’s population is about 1,800 people. The town of Grassy is located on the west coast and the town of Currie on the south coast.
15. Land used for primary production covers 94,000 ha of privately owned land and 1,250 ha of State Forest. Together, this represents 85 per cent of the area of King Island. The remaining 15 per cent of the island includes 5,865 ha of unoccupied Crown Land and 7,751 ha of conservation reserves.
16. The largest of the reserves, the Lavinia State Reserve, has an area of 7,033 ha. A wide range of habitats suitable for Bennett’s wallaby is represented in these reserves as well as the unoccupied Crown Land. No hunting of wallabies is permitted on reserved or Crown Lands.
17. The terrain of King Island is slightly flatter than Flinders Island with gullies. The road network and road composition is similar to that on Flinders Island.
Bennett’s wallabies and Tasmanian pademelons
DISTRIBUTION AND HABITAT
18. The Bennett’s wallaby is found from central Queensland to south-eastern South Australia and Tasmania. The Tasmanian pademelon is now found only in Tasmania having become extinct last century in South Australia and Victoria.
19. Bennett’s wallabies although abundant and widespread throughout Tasmania, are significantly more abundant on both Flinders Island and King Island. Tasmanian pademelons also abundant and widespread throughout Tasmania are significantly more abundant on Flinders Island. Both species occupy most forms of vegetation other that extensively cleared land. The clearing of areas of native vegetation for agriculture and the creation of a mosaic of bush, pasture and crops has enabled wallaby populations on both islands to increase to levels where numbers need to be controlled to limit adverse effects on agricultural production and the environment. Both species are particularly abundant where their natural habitat occurs adjacent to pasture.
20. The Tasmanian pademelon generally prefers dense forest whereas the Bennett’s wallaby can be found in open forests, heath lands and sedge lands. Bennett’s wallabies and Tasmanian pademelons are primarily grazing animals that feed on grasses and herbs, although, when required, woody plants are browsed. Both wallabies are primarily nocturnal. Marked peaks in feeding activity occur at sunset, late at night and in the early morning. Typically Bennett’s wallabies range further into open areas than pademelons which are rarely seen more than 100 metres from the bush edge.
21. Bennett’s wallaby has a well defined breeding season between late January and July with most births occurring in February and March. Female Bennett’s wallabies reach sexual maturity at 14 to 17 months and males at 21 to 22 months of age. The length of the oestrous cycle is approximately 33 days and the gestation period is about 30 days.
22. Pouch life of the single young is of about 280 days (9 months). Young are usually weaned three months after leaving the pouch.
23. Tasmanian pademelons have two distinct breeding seasons, one in late spring / summer and one in late autumn / winter. Female pademelons reach sexual maturity at about 13 to 15 months and males at 14 to 17 months. The length of oestrous and gestation is about 30 days.
24. The single young vacate the pouch after about 200 days (6.5 months). Young are usually weaned about one month after leaving the pouch.
25. There are three overlapping stages of pouch life: Stage 1 - pink joeys (hairless) that stay in the pouch all the time, Stage 2 - Joeys that are in and out of the pouch and Stage 3 - Joeys that spend most of their time out of the pouch. This latter class are commonly referred to as "at foot" joeys.
26. Macropods experience relatively high and variable mortality as juveniles and this is well documented and is typical of the life history pattern for large mammals. The literature reports a similar pattern for Tasmanian pademelons and Bennett’s wallabies in Tasmania. Mortality rates are highest in large pouch young and at foot young. Mortality rises to over 20 per cent when the young leave the pouch.
27. Drought is the main cause of lowered survival rates among the pouch young and juveniles of both Bennett’s wallaby and Tasmanian pademelon.
28. In heavily hunted populations competition for food was less and breeding success correspondingly higher. Indeed, hunting pressure was found to result in an improvement in the condition of the surviving members of the population, and to increase the survival of pouch young and juveniles.
29. The number of wallabies on King and Flinders Island has increased to a level which it is not sustainable. Not surprising given the absence of mammalian predators such as dingoes and foxes, the productive environment and habitat modifications (introduced pastures and crops, partial clearing) that have benefited these animals.
PRESENT MANAGEMENT METHODS
30. By virtue of Schedule 4 of the Wildlife Regulations 1999 Bennett’s wallabies and Tasmanian pademelons are classified as partly protected wildlife throughout Tasmania. They may be taken under the authority of a permit on properties where they are causing crop damage. And they may be taken during a declared open season by shooters hunting under the authority of a licence issued under s 30 of the Nature Conservation Act.
31. Crop Protection Permits are issued for a period of one to twelve months. Shooting may be undertaken by the landholder, their employees or family, or by other persons named on the permit as agents. No quotas existed on the numbers of Bennett’s wallabies and Tasmanian pademelons killed under crop protection permits before the Minister approved the wildlife trade management plans.
32. As a last resort, where shooting is attempted but found to be ineffective, the Department of Primary Industry, Water and Environment will issue permits to use 1080 baits but only after an inspection of the property by an officer authorized under the Nature Conservation Act. That officer must be satisfied that there is an unacceptable risk to the crop or pasture, that use of 1080 baits does not pose an unacceptable risk to a population of non- target species and that alternative control measures have been adequately considered and implemented as far as practicable.
33. It is Tasmanian Government policy to phase out the use of 1080 poison for native browsing animal control by 2015.
34. Despite landholders with Crop Protection Permits culling wallabies, the damage to crops, pasture and native vegetation in some areas of King and Flinders Island is increasing.
THE STATUTORY SETTING
35. The management plans in issue in these proceedings were approved by the Minister pursuant to s 303FO(2) of the Act. That section is within Part 13A, which is headed "International movement of wildlife specimens". The objects of Part 13A are set out in s 303BA(1) in these terms:
(1) The objects of this Part are as follows:
(a) to ensure that Australia complies with its obligations under CITES and the Biodiversity Convention;
(b) to protect wildlife that may be adversely affected by trade;
(c) to promote the conservation of biodiversity in Australia and other countries;
(d) to ensure that any commercial utilisation of Australian native wildlife for the purposes of export is managed in an ecologically sustainable way;
(e) to promote the humane treatment of wildlife;
(f) to ensure ethical conduct during any research associated with the utilisation of wildlife;
(g) to ensure that the precautionary principle is taken into account in making decisions relating to the utilisation of wildlife.
36. Section 303FO(1) of the Act provides:
The export of a specimen is an export in accordance with an approved wildlife trade management plan if the specimen is, or is derived from, a specimen that was taken in accordance with a plan declared by a declaration in force under subsection (2) to be an approved wildlife trade management plan.
37. There are a number of steps that must be taken before the Minister may declare a plan under s 303FO(2). First the Minister must not declare a plan under the subsection unless satisfied of the matters set out in s 303FO(3). And in deciding whether to declare a plan under s 303FO(2) the Minister must have regard to the matters set out in s 303FO(4), must consult a relevant agency of the State affected by the declaration (see s 303FQ) and consider any comments about the proposal received in the public consultation process specified in s 303FR.
38. It is now necessary to set out the terms of ss 303FO(3) and (4). They provide:
(3) The Minister must not declare a plan under subsection (2) unless the Minister is satisfied that:
(a) the plan is consistent with the objects of this Part; and
(b) there has been an assessment of the environmental impact of the activities covered by the plan, including (but not limited to) an assessment of:
(i) the status of the species to which the plan relates in the wild; and
(ii) the extent of the habitat of the species to which the plan relates; and
(iii) the threats to the species to which the plan relates; and
(iv) the impacts of the activities covered by the plan on the habitat or relevant ecosystems; and
(c) the plan includes management controls directed towards ensuring that the impacts of the activities covered by the plan on:
(i) a taxon to which the plan relates; and
(ii) any taxa that may be affected by activities covered by the plan; and
(iii) any relevant ecosystem (for example, impacts on habitat or biodiversity);
are ecologically sustainable; and
(d) the activities covered by the plan will not be detrimental to:
(i) the survival of a taxon to which the plan relates; or
(ii) the conservation status of a taxon to which the plan relates; or
(iii) any relevant ecosystem (for example, detriment to habitat or biodiversity); and
(e) the plan includes measures:
(i) to mitigate and/or minimise the environmental impact of the activities covered by the plan; and
(ii) to monitor the environmental impact of the activities covered by the plan; and
(iii) to respond to changes in the environmental impact of the activities covered by the plan; and
(f) if the plan relates to the taking of live specimens that belong to a taxon specified in the regulations – the conditions that, under the regulations, are applicable to the welfare of the specimens are likely to be complied with; and
(g) such other conditions (if any) as are specified in the regulations have been, or are likely to be, satisfied.
(4) In deciding whether to declare a plan under subsection (2), the Minister must have regard to:
(a) whether legislation relating to the protection, conservation or management of the specimens to which the plan relates is in force in the State or Territory concerned; and
(b) whether the legislation applies throughout the State or Territory concerned; and
(c) whether, in the opinion of the Minister, the legislation is effective.
THE ISSUES RAISED
39. In the course of the Tribunal’s pre-hearing processes and the hearing itself a number of discrete issues were identified, either by the applicant or by the Tribunal. In formulating the issues in the manner that follows we have relied to some extent upon the final submissions helpfully prepared by Mr O’Brien, who appeared for the applicant. In addition, we have added an issue that was raised by the Tribunal in the course of the hearing and addressed by counsel for the Minister. They issues, as we apprehend them to be, are:
1) do the management plans permit the hunting of wallabies and pademelons, and the treatment of joeys, in an inhumane manner having regard to,
a. the failure to dispatch at foot joeys,
b. the use of rimfire (as distinct from centrefire) cartridges in commercial harvesting,
c. the possibility of animals being shot otherwise than by a "brain shot"?
2) are the quotas adopted by the management plans based upon population data that is erroneous, inaccurate or misleading?
3) should the management plans include further measures to monitor the effects of commercial harvesting to ensure that it is ecologically sustainable?
40. As we have noted in discussing the statutory setting the Minister (and thus the Tribunal on review) is required to be satisfied that the management plans are consistent with the objects of Part 13A of the Act. That includes the object in s 303BA(1)(e) "to promote the humane treatment of wildlife". Before considering the applicant’s contentions we should first examine how the management plans deal with the issue of humane treatment as they are presently formulated.
41. Both management plans deal with the issue in the same way. In the section of the plans headed "Animal Welfare" reference is first made to the Tasmanian legislation that deals with the prevention of cruelty to animals, including wallabies, and the promotion of animal welfare, the Animal Welfare Act 1993 (Tas.) That Act, by s 44, provides for the approval by the relevant State Minister of Animal Welfare Standards. An Animal Welfare Standard for the Hunting of Wallabies in Tasmania was approved in June 2003. The management plans require, as a condition of commercial hunting permits to be issued under them, that wallabies be taken in accordance with the requirements of that Welfare Standard.
42. The Welfare Standard sets "Recommended Minimum Requirements" for shooting with rifles. They include the requirement to target the animal’s head so as to hit the brain. The use of a telescopic sight is mandatory. A table of recommended firearm and ammunition suggests that .22LR ammunition with a minimum muzzle energy of 190 joules be used to a maximum distance of 50 metres, that .22 magnum ammunition with a minimum muzzle velocity of 370 joules be used to a maximum distance of 80 metres and that centrefire ammunition with a minimum muzzle energy of 975 joules be used for distances over 80 metres.
43. The Standard also requires that wounded animals be despatched as quickly and humanely as possible and that adult females killed be examined promptly for pouch young. Any found must be humanely killed without delay.
44. The management plans, having set out the requirement to comply with the Standard, then continue:
In addition, shooters operating under Commercial Wallaby Hunting Permits will be required, as a condition of their permit, to adhere to the following requirements:
• The permit holder must only target animals that are clearly visible, stationary and within a range that permits an accurate shot. Shooting is not permitted from a moving vehicle or other moving platform.
• The permit holder must aim so as to hit the target animal in the brain, except in the case of a wounded animal, where a brain shot might be impractical.
• The permit holder must use a rifle fitted with a telescopic sight that has been sighted in against an inanimate target prior to commencing each day’s shooting,
• The use of shotguns and/or dogs is not permitted.
These conditions have been added in order to ban use of shotguns and/or dogs by commercial shooters and bring the Standard into line with the National Code of Practice for the Humane Shooting of Kangaroos (1990) with the exception that rimfire rifles are allowed. The National Code of Practice for the Humane Shooting of Kangaroos (1990) is currently under review and the issue of rimfire rifles is being considered in the review. Permit conditions may be amended so as to reflect any changes made to the National Code during the period of this plan.
All holders of commercial wallaby hunting permits must be appropriately trained and accredited.
45. Some of the concerns of the applicant may be immediately disposed of. Dr Martin Denny, a zoologist called by the applicant, takes issue with the Tasmanian Animal Welfare Standard in relation to four issues – the fact that the use of shotguns is permitted, the fact that dogs may be used, the fact that it is still allowable to shoot a wallaby in the chest instead of the head and the fact that rimfire cartridges may be used. As to the first three of these matters the management plan adds to the requirements of the Standard the additional prohibition on the use of shotguns and dogs and the permit holder must aim so as to hit the target animal in the brain, except in the case of a wounded animal, where a shot to the brain of a wounded animal is impractical or unsafe, a shot to the heart is permissible. We deal below with the fourth matter raised by Dr Denny, the use of rimfire cartridges.
46. We want to deal first with the issue of the treatment of joeys. It is undoubtedly the reality of hunting wallabies that from time to time an adult female will be shot in circumstances where joeys will be orphaned. It is difficult for hunters to distinguish between males and females. Where females are killed the hunter is required to examine for pouch young. Dr Jon Hanger, whose sincerity cannot be doubted, was concerned that forcible removal of pouch joeys from the teat might cause tearing of the soft tissues in the mouth and suggested that joeys ought be separated from the dead mother by cutting the teat. Mr Neville Price, an employee of the Tasmanian Department of Primary Industries, Water and Environment with vast experience over years in the hunting of wallabies, regarded this practice as increasing the suffering and distress of the joeys by prolonging the period before dispatch. Rather, Mr Price suggested that hunters favoured methods which involved decapitation of pink joeys on the teat and despatching larger pouch young by using a heavy blow to the head causing what Mr Price described as a quick and painless death.
47. It is unnecessary for us to decide which of these methods should be preferred. But we can say that we do not regard the methods outlined by Mr Price as being other than humane treatment. The difference between the method preferred by Dr Hanger and that apparently utilised is, in our view, of no moment. Both methods produce a fast and humane death.
48. There is, as well, the question of at foot joeys. The evidence of Mr Price, which was not challenged, was that joeys that were under half the size of the mother or that stayed with the killed mother were despatched in the manner that we have discussed or by humanely shooting the joeys in the brain. Larger joeys, and joeys that had fled from the mother or did so as the hunter approached were regarded as being capable of surviving outside the pouch and were not dispatched. Mr Price considered that joeys of that age could survive, especially given the absence of other predators such as foxes or dingoes. Although we do not doubt the sincerity of Dr Hanger’s evidence it does not lead us to conclude that at foot joeys are dealt with in an inhumane manner.
49. The case for the applicant regarding the choice of ammunition was that .22 rimfire ammunition ought not be permitted. It relied on the evidence of Dr Paul Hopwood, a veterinarian of many years standing who is, as well, a very experienced shooter. But when analysed, his evidence is not significantly at odds with that of Mr Ian Prior, a ballistics consultant with many years experience.
50. It will be recalled that the management plan adopts the Tasmanian Animal Welfare Standard which, in turn, recommends that hunters use .22LR ammunition for distances up to 50 metres, .22 magnum for distances from 50 to 80 metres and centrefire ammunition for distances over 80 metres.
51. Both Dr Hopwood and Mr Prior considered that .22 rimfire rifles are appropriate for distances up to 50 metres. Dr Hopwood said, on this topic:
.22 rimfire rifles are appropriate to use on small game taken at close range. Where an animal can be targeted in the head kill zone then good animal welfare outcomes can be achieved with .22 rimfire rifles to approximately 50 metres.
The evidence of Mr Prior was to similar effect. Both Dr Hopwood and Mr Prior considered that .22 magnum rimfire ammunition was capable of killing at distances up to 80 metres in a way that minimizes pain and suffering to the animals.
52. In addition the evidence before us from Mr Price was that on both islands nearly all wallabies harvested were shot at a range of no more than 50 metres. Mr Gregory Hocking, a zoologist employed by the Department of Primary Industries, Water and Environment, who has much practical experience with the wallabies and who has conducted population surveys on the islands for many years was also of the view that wallabies could be shot at close range without the need to take long range shots.
53. As it seems to us, where targets at 50 metres or less are plentiful a hunter is unlikely to take longer shots and increase the chances of only wounding an animal. Where that happens the hunter must cease hunting until the wounded wallaby is located and killed. It defies common sense for a hunter to shoot beyond the capabilities of the .22 rimfire rifle where there is no need to do so and where there is a positive disincentive (the risk of having to cease hunting) to do so.
54. Where the experts agree that .22 rimfire rifles provide good animal welfare outcomes at distances up to 50 metres and the evidence is that most animals are taken at that range or less we do not consider that the use of .22 rimfire ammunition will lead to inhumane outcomes for the animals.
55. We note the evidence of Mr Price regarding the process of accreditation of commercial shooters. They are required to undertake a Certificate Course in Meat Processing which involves, amongst other things, field shooting assessments. These assessments, which are conducted by Mr Price, are detailed and are obviously designed to ensure that only proficient hunters are accredited to harvest game for human or pet consumption. In addition shooters are subject to tri-annual assessments once accredited.
56. We have otherwise carefully considered the matters in the management plans that concern the manner in which the wallabies are hunted and are satisfied that the management plans promote the humane treatment of the wallabies.
57. We start with an explanation for the way in which the quotas are set. The management plans operate on the basis of population density, that is, the number of animals per square kilometre. Population densities have been monitored on Flinders Island since 1991 and on King Island since 2001. Population densities, rather than counts of actual size are used on the islands because of the environmental characteristics such as the terrain, vegetation cover and the nocturnal behaviour of the harvested species. This monitoring is undertaken through a system of standardised spotlight survey counts performed bi-annually across those parts of the islands where animals are harvested. They are not carried out in areas e.g. reserves, where there is no harvesting.
58. Only an index of population size is possible on Flinders and King Islands, which requires a different harvesting strategy. Indices are commonly used in harvest programs throughout the world. The harvest strategy employed by the Department Primary Industry Water and Conservation is to offer an annual quota dependent on the value of an index of population size. This contrasts with the harvest management of kangaroos on the Australian mainland where the annual quota is a proportion of an estimate of population size. The latter is feasible on the mainland where surveys, usually aerial surveys, can provide representative samples of the population.
59. It is unnecessary, given the nature of the applicant’s case, to set out in any great detail the way in which both management plans operate in relation to both Bennett’s wallabies and Tasmanian pademelons. It will suffice to refer only to the Flinders Island management plan and its determination of quotas for Bennett’s wallabies.
60. The management plan for Flinders Island gives the most recent population density estimates (with % coefficient of variation) as:
• Bennett’s wallabies 68 (25%),
• Tasmanian pademelons 220 (33%).
On this basis the populations across private land are estimated at 50,000 Bennett’s wallabies and 160,000 Tasmanian pademelons.
61. The bi-annual monitoring by spotlight survey counts using line - transect methodology will continue and annual quotas will be set on the basis of those figures and the figures for non-commercial harvesting. The management plan operates on the basis of trigger points. Thus, if the population density index for Bennett’s wallabies is above 40 km2 and the non-commercial quotas have been set at 4,000, then the commercial quota will be set no higher than 11,000. If the population density for Bennett’s wallabies is in the range 30 to 40 km2 and the non-commercial quota is set at 3,000, then the commercial quota will be set no higher than 9,000.
62. The management plan operates in this way through a range of trigger points. The management plan adopts the range of 10 to 20 km2 as the lower target range for the population of Bennett’s wallabies on Flinders Island in order to minimise adverse impacts, whilst ensuring the sustainability of the species and the commercial harvest. At population densities fewer than 10 km2 commercial harvesting would cease.
63. The argument advanced for the applicant, as we apprehended it to be, was not directed to this methodology as such, rather it was directed to the reliability of the population density data. The argument was put in this way in the applicant’s final submission:
In brief, this argument is that the quota is based on erroneous, inaccurate or misleading population density data which has overstated the numbers of wallabies and pademelons. As such, the Minister has not properly satisfied himself that the impact on the species is ecologically sustainable, which is a pre-requisite of the approval of a Management Plan under s 303FO(3)(c) of the [Act].
64. This argument was advanced on the basis of the evidence of Dr Denny and, as it seems to us, does not fairly represent the evidence of Dr Denny. His criticisms of the Flinders Island management plan referred to:
the limitations to the survey methodology from road-bias effects, and does not include the entire island in the calculations.
Dr Denny also suggested that harvesting rates were much too high, and pointed to an example where the recommended harvesting rate was above 50% of the population. Dr Denny said, of the Flinders Island management plan, that commercial and non-commercial quotas should be set lower when density indices fall below 40 km2 for Bennett’s wallabies and below 110 km2 for Tasmanian pademelons although his report provided no particular basis for that conclusion.
65. In relation to the King Island management plan Dr Denny said:
At present, the population estimate for Bennett’s Wallabies on King Island is the product of guesswork and should not be considered as having any reliability. Between the May 2005 version of the Plan of Management and the Plan on display (dated September 2005) there have been changes to the density indices for Bennett’s Wallabies. In May, the 2003 density index was 48.2 animals/km2, whilst in September, the index had fallen to 40.6 animals/km2...Also the 2004 index had changed from 56.9 to 53.4 animals/km2. This is presumably because more surveys have been undertaken, but why was the 2003 index lowered?
66. Dr Denny made reference to reports that he had received of very large quantities of 1080 baits having been laid with very high animal deaths and concluded that until a more accurate and reliable density index could be provided for Bennett’s wallabies, particularly after a large non-commercial kill, the King Island management plan ought not be accepted.
67. Whilst we do not doubt the sincerity of Dr Denny’s beliefs we are unable to accept some of his conclusions for the reasons that we detail below.
68. There were two criticisms of the Flinders Island population density figures – road bias and the fact that it is a sample less than the entire island. As to that latter point, logic, as well as the evidence on the respondent’s side, would suggest that, if anything there would be higher population densities on those areas of the island where there was no hunting, whether commercial or non-commercial. The question of road bias was the subject of a good deal of evidence; it is common ground that there is a road bias but the parties are at odds as to its effect.
69. To Dr Denny, road bias occurred because animals were attracted to the roads – because of greener pasture on the verges of the roads from the effect of moisture run off from the roads and because the roads absorbed more heat during the day and were accordingly warmer at night that the surrounding pasture. Thus, in his view, sampling done from the road (as all sampling was) would inflate population densities because there would be a greater concentration of animals in the vicinity of roads than in other areas. The contrary view was that the vegetation on the verges of the roads was less palatable to the wallabies and thus less attractive.
70. In the result we have not found it necessary to reach any conclusion on this aspect. That is because we accept, as Dr Anthony Pople points out, that whatever the bias, it will be a constant, and changes to density will be unaffected. Dr Pople, who has vast experience in population ecology, put the matter in this way:
There is a recognised bias in the vehicle surveys, which may be positive or negative. The direction or size of the bias is not important. What is important is that the index is repeatable. In other words, the index, whether it is an actual density along roads or counts of tracks or other signs of animals, needs to track changes in the size of the population. Calculating estimates of population size and associated harvest rates are inappropriate.
71. There is, with respect, nothing in Dr Denny’s criticism of the fact that the quota can be, in some circumstances, set at 50% of population. Even at a fairly superficial level that argument lacks logic. But the better answer is provided by Dr Pople in this way:
[Dr] Denny’s comments appear to confuse the harvest strategy with the proportional harvesting strategy for mainland kangaroos. If the population is above a high trigger point, then it may will be appropriate to harvest at high rates >50%. Of course these rates are unlikely to be sustainable if applied in the long-term, but they are only applied while the population is above a particular trigger point. Indeed a theoretically optimal (in terms of yield) harvesting strategy is to harvest all animals above a particular density threshold and harvest none below the threshold.
72. Dr Pople responded to Dr Denny’s criticism of the King Island management plan (set out in paragraph 63 above) in this way:
[Dr Denny] also makes statements about changes in numbers of Bennett’s wallabies on King Island from 2001-2004, completely ignoring the confidence intervals around the estimate and the fact that the numbers cannot be compared with actual harvest figures..
73. What Dr Denny said of the 1080 baiting programme is also demonstrated, on the evidence we accept, to be overstated. Mr Hocking regarded the figure of 200,000 used by Dr Denny as "unrealistic" but, of more importance is the evidence of Mr Hocking that a large proportion of baits were not taken and were collected, and that approximately 2,450 wallaby carcasses were collected as a result of the baiting programme in April 2005. Even if a similar number were to have gone to inaccessible areas to die the total number of deaths is very small when compared to Dr Denny’s figure. But it is significant, we think, that one of the aims of the management plan is to avoid the use of 1080 baits where possible.
74. The evidence of Dr Pople and that of Mr Hocking is, we think, detailed and it satisfies us that there has been appropriate consideration of the likely impacts that the proposed commercial harvesting will have on the animal populations.
FURTHER MONITORING MEASURES
75. In the course of the hearing we raised with the respondent’s witnesses whether it was desirable or necessary that some additional monitoring of harvesting be undertaken. We had in mind the notion that if, as seems to be the case, male wallabies tend to be larger than females and hunters tend to target the larger animals, there might be a risk that the adult male population could be reduced dramatically and, perhaps, dangerously. We are concerned, as well, that no statistics are maintained of age/sex class ratios.
76. One of the objects of Part 13A, set out in s 303BA(1)(d), is to ensure that any commercial utilisation of Australian native wildlife for the purpose of export is managed in an ecologically sustainable way. Additionally, s 303FO(3)(e) requires us to be satisfied that the management plans monitor the environmental impact of the activities covered by the plans.
77. In approaching this task it is as well to recall, as Preston CJ of the New South Wales Land and Environment Court said recently:
Ecologically sustainable development is fundamental to meeting the needs of the present and future generations. It is a touchstone, "a central element", in decision-making relating to planning for and development of the environment and the natural resources that are the bounty of the environment [citations omitted].
78. Dr Hanger was asked whether, in setting quotas for harvesting populations of wallabies and pademelons on Flinders Island and King Island, there was a need to incorporate date or age and sex structure in the monitoring program as a measure of ecological sustainability. He acknowledged that total number, by itself, may be misleading and stated:
...there certainly is a danger in just looking at total numbers, and if you really want to be very good and thorough and objective about it, then you really should be paying attention to the population demographic to make sure that you’re not selectively taking out individuals such that the population sustainability is affected.
79. Dr Denny also commented on the issue. His view was that age classes and sex ratio were two other factors that were quite sensitive measures of the health of a population. He acknowledged that these characteristics had not been incorporated into the management plan as it would be very difficult to try to count numbers and note and record age and sex characteristics whilst spotlighting. However, he acknowledged that it could be done at the abattoir: "Obviously, with the carcasses, there is an opportunity there of doing it, but as far as I can see, there's no data that I've seen on it".
80. It was Dr Denny’s opinion that the absence of such information may have implications for the ecological sustainability of the Bennett wallaby and the Tasmanian pademelon. He said:
Well, I think at this stage that all the eggs were in one basket by just having density indices alone, whereas other factors would be - and particularly, reasonably simply obtained and with - some good statisticians, could work out trends in your population far more sensitively
81. Whilst the sampling methodology used to estimate the number of wallabies and the pademelons on Flinders and King Island was not in dispute, Dr Denny was asked whether there was a standard approach from science as to what would be considered to be an acceptable level of error associated with that methodology whilst undertaking field sampling of marsupial populations. Dr Denny explained that science relied on the concept of "coefficient of variation" which was a measure actually taken from a whole range of numbers upon which the mean (or average) was calculated; where the whole range of numbers was very wide, the variation would be very high. The coefficient of variation (expressed as a percentage) was a measure of the variation in that range. A general figure for coefficient of variation which science accepted as a suitable coefficient of variation, and one to aim for, was to keep the coefficient of variation:
...around about that 15, 20 per cent, you're in a situation where it is a workable number. When you start climbing above that, you start to get a bit worried about the range that's there.
82. Dr Denny expressed concern that the indices were used to estimate populations for the Bennett wallaby and the Tasmanian pademelon on Flinders Island and King Island and applied to the entire area of each island – rather than just the harvestable area. That is, it was inferred that the indices estimated from the sampling methodology were representative across the entire area of each Island – and not just the harvestable area only. It was his opinion that:
the ‘entire area’ had to be defined, and I've defined the entire area as the harvestable area, as opposed to the entire island area, because it's the harvestable population that is the one that's under threat, and so I have taken my area as that.
83. Mr Hocking was responsible, inter alia, for describing the direction of trend, over time, in population numbers of wallabies and pademelons on Flinders Island and King Island. Population numbers were based on the mean (or average) density index calculated following sampling of populations at different points in time.
84. He was asked to what extent he had looked at both the coefficient of variation and the mean value for density index – including what form of statistical analysis had been used, to arrive at his conclusions for trend in population numbers over time. Mr Hocking conceded that his evaluation was based on the overall trend in the mean density indices by looking at a succession of results over time – without the variability in coefficient of variation.
85. Mr Hocking was asked about what factors were needed to be considered in relation to the question of ecological sustainability and the harvesting of the Bennett wallaby and Tasmanian pademelon. His view was that the extent of the population being harvested had to be considered as well as populations in areas that were not being harvested e.g. Crown reserves, being taken into account. However, he conceded that "we don’t have a density estimate for those populations [areas not harvested]".
86. When asked about factors such as age and sex class of the population being harvested, Mr Hocking stated, "Yes, of course, its going to impinge on sustainability...that has to be taken into account". Mr Hocking referred to a study on the Bennett’s wallaby (a MSc Dissertation submitted to the University of Tasmania in 1992) that identified amongst other things, the composition of what hunters were actually shooting in terms of both age and sex class. Whilst this information had been taken into account by the current management plan, Mr Hocking conceded that the current harvesting processes did not record this information.
87. Mr Hocking’s evidence, like that of Mr Price, was that harvesters tended, more often as not, to take the largest animals. For the Bennett’s wallaby, this tended to be the male. Mr Hocking agreed that the male Bennett’s wallaby was not generally noticeably larger than the female, there being probably about a 20% difference in size.
88. Mr Hocking expressed the opinion that adverse impacts on gender balance due to harvesting could be offset by monitoring. "Sex could be very easily monitored" and, he thought, that could be done at the processing plant or it could be made a requirement for the harvester to record that information. Age class would be a little more difficult but could be an evaluation on a qualitative scale as a function of "stage of maturity". He envisaged no great difficulties in recording age and sex class information.
89. Dr Pople referred to harvesting programs for mainland kangaroos where data on sex ratios is collected at harvest and that this data could be useful to indirectly monitor the population. As the sex ratio changed, it could indicate what was happening to the population – either the population size or the status of the population. However, Dr Pople was "unsure" whether sex ratio and age distribution of the harvest would necessarily aid the monitoring as the harvested species may not necessarily be representative of the population. For example, in arid areas of Australia the age structure and sex ratio changed markedly, certainly through drought.
90. In relation to the management plans in issue here Dr Pople was asked to comment on whether the trend in population numbers over time would be the same whether based on the mean density indices alone or based on the mean density indices and the associated coefficient of variation for each density index. He said:
Yes, it may not ...because, I mean, certainly if you look at the year to year trend... the confidence interval is so broad, you wouldn’t be able to confidently say that the population had increased or decreased. You could say that it’s likely to have increased...
He did say, however, that the probability for a likely increase in trend over time had not been calculated.
91. In the opinion of Dr Pople the key point was not so much whether the trend over time was increasing or decreasing, but whether the estimates of population size had reached a trigger point where the density should trigger off a change of management practice. However, he conceded that the precision of the estimate for the density index was dependent on how far the value was above the trigger point. Where the value was well above the trigger point, there would be little concern for having a very precise value. However, where the value hovered on the edge of the trigger point, a precise, statistically reproducible value was necessary.
92. Dr Pople considered that spatial refuges were an important component of the wildlife management plan, as they represented areas where wallabies could not be harvested and so represented an "important safety net". He referred to the existence of "quite large national parks... on both King and Flinders Island, where you would have wallabies that would spend most of their lives just in the national park". The rationale behind spatial refuges, such as the national parks on King and Flinders Island, was that they provided "immigrants" to repopulate the species that were harvested.
93. In our view the density index methodology for estimating population size of wallabies and pademelons is adequate for setting of harvest quotes in most years, subject to the following qualification. There would be some degree of uncertainty in years where the estimated value hovered close to the trigger point because of the inherent variability in the coefficient of variation that affects the precision and statistical reproducibility of estimates. But we consider that those charged with the management of the resource will be conscious of the need to ensure particular care with population density estimates close to the trigger points.
94. One limitation in the management plan that does concern us is its failure to provide any age or sex class of the harvested populations. In this regard there is consensus in the expert evidence before the Tribunal that measures could readily be taken to obtain that data and that population studies will be better informed for having access to that information.
95. We would propose to vary the decisions under review to include a requirement in each plan that the sex and an estimate of age of all harvested animals be recorded at, or following, harvesting. We propose to provide these reasons to the parties and invite them to consult on an appropriate form of words that can be added to the management plans.
96. We have had regard to the concerns expressed by some witnesses that no population studies have been undertaken in Crown reserves and the like. It is the case that the management plans assume that population densities in harvested areas can be extrapolated to non-harvested areas. Whilst there is no evidence to suggest that this assumption is invalid there is, equally, no evidence to suggest that it is valid. Dr Pople spoke of the importance of these areas and described them as a "very important safety net" for the management plan.
97. Given that importance, we consider that it would be prudent that some attempt be made to estimate population densities in non-harvested land to ensure that the assumption regarding population densities in those areas is not entirely false or, at least, dangerously at variance from the assumption made. We do not regard this as warranting an amendment of the management plans, rather we regard this as a matter where those charged with the administration of the plans should give consideration to estimating populations in these areas to ensure that the areas are not devalued in any way and remain as spatial refuges for the animals.
98. We should say that we do not regard that conclusion as being affected by the contents of a statement of Mr Hocking dated 20 October 2006 and received by the Tribunal after the foregoing had been written. Given the lateness of its arrival we have not taken it into account.
99. We are otherwise satisfied that the measures included within the management plans are adequate to monitor the populations and the numerous safeguards within the management plans mean that no one decision or response can render the commercial harvesting of Bennett's wallabies and Tasmanian pademelons a threat to the species.
100. The matter will be adjourned to a date to be fixed to enable the parties to consider and agree, if possible, the form of amendment to the management plans required to give effect to these Reasons.