A report on the impacts on the importation of Leggett’s Rainbowfish, Glossolepis leggetti, for use as an ornamental aquarium species in the Australian Aquarium Trade. Prepared by Dave Wilson1*, Glenn Briggs2 and Danny Brown3
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Include, but do not restrict your response to5.1 The Natural Geographic Range Glossolepis leggetti is only known from one location in the Wapoga River and three locations in the Tiawiwa River, Papua New Guinea from the collections of Gerald Allen and Samuel Renyaan during 1998. 
The image is downloaded from the Google Earth satellite images of the earth available from the Google Earth program downloaded from URL http://earth.google.com . The latitude and logitude coordinates from the four stations where Allen and Renyaan collected Glossolepis leggettii are recorded on the photograph. Station 1 Tiawiwa River 3o 02.665’ South 136o 22.336’ East Station 3 Braid of Tiawiwa River 3o 02.792’ South 136o 22.852’ East Station 8 Tiawiwa River near abandoned logging camp 3o 02.141’ South 136o 22.656’ East Station 9 Wapoga River tributary 2o 42.378’ South 136o 05.401’ East 5.2 Habitat, specifically mention upper and lower ranges for: temperature, pH, salinity and oxygen Allen and Renyaan (1998) recorded Glossolepis leggetti from 4 collection stations on the Tiawiwa and Wapoga Rivers during April 1988. Water quality and habitat descriptions were recorded as follows for those locations:
The only records are for April, therefore it can be assumed that there will be slightly different environmental conditions through the remainder of the dry season and cooler water with a higher flow rates during the wet season. In Summary : Temperature - 26.2 to 30.7 Salinity - fresh pH - 6.0 to 8.4 The substrates range from fine sand to limestone rock and from the pH range one could also assume the water hardness would most likely be from quite soft to very hard. These assumptions are based on the experience of the author measuring water qualities in various locations across the North of Australia. The results of many water quality and habitat observations are recorded on the Australia and New Guinea Fishes Association (ANGFA) data base. Access to the data base is available via a password on the world wide web at the uniform resource locator http://db.angfa.org.au.. Any person reviewing this part of the document may obtain username and password for the database from the database administrator. 5.3 Diet The specific diet of Glossolepis leggetti was not recorded by Allen and Renyaan (1998) but the diet of other members of the Glossolepis genus are well recorded. All rainbowfishes of the family Melanotaenidae are reasonably similar in their dietary preferences. They are omnivores, eating a variety of small aquatic and terrestrial creatures and plant matter. Rainbowfishes have villiform teeth that extend outside their mouth around their lips to enable them to scrape algae from submerged hard surfaces. The diet includes algae, ants, aquatic insect larvae and small crustaceans. (Allen 1991) 5.4 Social behaviour and groupings There is no specific description for the social behaviour of Glossolepis leggettii but there is general descriptions for the behaviour of rainbowfishes. There is no indication that Glossolepis leggetti is different from other rainbowfishes. Allen (1991) describes the general behaviour of rainbowfishes as small schooling fishes generally less than 12 cm in length and common in most habitats below 1500m elevation. The habits of other members of Glososlepis genus in captivity are well documented. Allen & Renyaan (1998) indicated that Glossolepis leggetti is most closely related to G. multisquamatus. Behavioural observations for G. multisquamatus are typical for most rainbowfishes and may be considered indicative of the behavior of the proposed species, G. leggetti. Tappin (2005) gives the following general descriptions of rainbowfish behaviour in the aquarium ; “Rainbowfishes have very similar breeding habits, their food requirements are similar, and water that suits one particular species will suit all. All are of good-natured temperament and will live harmoniously, more or less, with one another. Rainbowfishes are a schooling fish , living in the mid-water to the surface zone, often adjacent aquatic and emergent vegetation or snags in deeper water and in the quieter parts of streams at the head and bottom of riffles and rapids. From first light to mid morning dominant males will intensify in colour, select a feature such as a prominent piece of aquatic vegetation or small snag then attempt to lure and chase females into the area at the same time displaying erect fins to other nearby males trying to attract the same females. Males with close areas will sometime circle each other flaring their fins. This rarely causes any damage and as it is mostly stylized display to establish male dominance. Females generally select the male they mate with and the pair quiver side by side for a few seconds near the chosen feature before a simultaneous release of eggs and sperm. The pair split apart in a rapid burst, scattering the fertilized eggs into the vegetation. The eggs have sticky filaments and are generally caught in the vegetation where they remain for 5 to 11 days before hatching into well formed larvae with very small yolk sac.”
There is no information to indicate members of the rainbowfish family Melanoteanidae have any auxiliary lung to assist in low oxygen situation 5.6 Characteristics or behaviour that enable the species to survive drought or other adverse conditions (e.g. hibernation or aestivation). There is no information to indicate members of the rainbowfish family Melanoteanidae have any ability to aestivate or any evidence that their eggs can survive desiccation. There is a pronounced difference between the topography of Australia and that of New Guinea. The extensive mountain ranges that run from east to west forms an effective isolating mechanism. The freshwater ichthyofauna can be clearly divided into two biogeographical regions. Freshwater bodies to the south of the central mountain range have an ichthyofauna closely allied with that of northern Australia. Rainbowfishes inhabiting river systems in the north are by and large different species from those in southern water bodies. In addition to the physical land barrier formed by the central mountain range, northern rivers are additionally much younger than southern rivers. 6. Provide information on the reproductive biology of the species There is no record of any work done on the reproductive biology of Glossolepis leggetti but the description of the Glossolepis leggetti by Allan and Renyaan (1988) states that it most closely resembles Glossolepis multisquamatus which is a species that is well known in the aquarium trade and has been kept and bred by the authors since 1983 from stock obtained from Melbourne. Three other Glossolepis species are well known in Australia; Glossolepis maculosus, Glossolepis incisus and Glossolepis wannamensis. The members of this genus were imported by various persons from wild New Guinea populations up until 1986 when further import controls were placed on live ornamental fish importations. 6.1 The age at maturity (first breeding) and lifespan of the species There is no record of this information for Glossolepis leggetti but generally Rainbowfishes start to breed about 6 months of age and are reported to live for about 4 years in their natural habitat and up to 8 years in captivity. 6.2 Ability of individuals to change sex There is no record of any Rainbowfish species changing sex such as some other native Australian fishes such as barramundi and clownfish. 6.3 Single sexed (ie either male or female) vs. hermaphroditic (ie have both male and female reproductive organs) There is no record of any normal members of the Rainbowfish family having the organs of both sexes existing within the same fish. 6.4 Frequency of breeding There are no records or observations for Glossolepis leggettii but closely related Glossolepis species will produce about 40 to 100 viable eggs a day for several consecutive days in a two week period. This amount of egg production will continue during times of good water quality and abundant foods which would occur for several months before, during and shortly after the wet season. 6.5 Sperm storage There is no record in any Rainbowfish books or papers examined of this family being able to store sperm. Rainbow fish are egg scatterers with eggs and sperm ejected simultaneously requiring both sexes for a successful fertile egg laying. 6.6 Number of eggs or live-born offspring produced at each breeding event There are no records for Glossolepis leggettii but closely related Glossolepis species will produce about 40 to 100 viable eggs each day for several consecutive days in a two week period. This amount of egg production will continue during times of good water quality and good food availability which would occur for several months before, during and shortly after the wet season. 6.7 Hybridisation with other species (both in the wild and in captivity) Reports of naturally occurring rainbowfish hybrids in the wild are extremely rare. A report of naturally occurring hybrids between the genera Melanotaenia and Chilatherina can be found in Allen & Cross (1992) but there are no known naturally occurring hybrids between Glossolepis sp. and Melanotaenia sp.. G. leggetti shares its habitat with Chiliatherina alleni, Melanotaenia praecox and M. rubripinnis.There are no naturally occurring Glossoplepis species in Australia. Despite the fact that some species of Glossolepis have been kept as aquarium fish in Australia for several decades this genus has never established feral populations here. Based on Allen (1989) and other works, the species in this genus have evolved in isolation from each other and almost certainly differences in courtship and spawning behaviour would have evolved at the same time (indeed, such isolating mechanisms must be available in this one habitat for two or more taxa to have evolved to the level of genus!). Distinct species as we know them have evolved as separate breeding units because of physicochemical, behavioural and recognition cues . These are complex and species-specific and effectively restrict hybridization That many species of rainbowfish are being raised in ponds adjacent to each other by breeders in Asia and elsewhere (and it is so unlikely that the tanks would always be uncontaminated), negates the likelihood of easy hybridisation between this and other rainbowfish taxa. There are reports, both published and anecdotal, of hybridisation between the various species of Melanotaenia, Glossolepis, Chilatherina and Rhadinocentrus as well as between genera. Virtually all of these have taken place either accidentally or on purpose under the artificial conditions within captivity. This species has never been kept in captivity as far as the enquiries of the authors can establish. There were no record or mention from Dr Allen of any hybrids of this species in its natural location. Hybridisation in rainbowfishes , although rarely occurring in nature, can be forced in the aquarium by providing only one sex of two different species. A closely related species, Glossolepis incisus was hybridized with a Melanotaenia praecox by Jarred Patrick of Bay Tropical Fish of Brisbane. The resulting offspring were infertile. Overseas ( Europe and USA) some attempts have been made to establish “aquarium” strains of hybrids between various Melanotaenia species and none of these have become established in the trade, mainly because of hobby , club and market resistance to such crosses . The hobby groups overseas such as the RSG (Rainbowfish Study Group, in the USA) and the IRG (in Europe) and ANGFA here in Australia regularly advise hobbyists against buying or perpetuating such hybrids even when they are disguised under “pseudo-scientific” names such as Melanotaenia marcii etc. Hobbyists engage in continuous dialogue on various aspects of husbandry and conservation of rainbowfishes (as well as other species ) on the Internet and various discussion forums in several languages.
http://www.environment.gov.au/biodiversity/trade-use/exoticfish/index.html The Australian Quarantine and Inspection Service received Policy Review advice 2009/24 from Biosecurity Australia issued 02 October 2009, “Importation of Rainbowfish for Ornamental Purposes”. It outlines the conditions under which members of the family Melanotaenia can be imported into Australia for ornamental purposes. 9.2 The Northern Territory The Northern Territory Department of Primary Industry, Fisheries and Mines will not allow Glossolepis leggetti across its border unless it has passed the Commonwealth guidelines for acceptance into the country. The list of species of fishes allowed into the Northern Territory for ornamental fishes is the same as Commonwealth list but with the possibility of having the species rejected if it is deemed unsuitable by the NT Minister for Fisheries as outlined in section 26 of the Northern Territory Fisheries Regulations 2001. The most current version of the Northern Territory Fisheries Act is available on line at universal resource locator - http://dcm.nt.gov.au/strong_service_delivery/supporting_government/current_northern_territory_legislation_database 8.3 The Queensland Government. The aquarium fish trade control comes under the Queensland Fisheries Act 1994 and the Queensland Fisheries Regulation 1995. Sections 88, 89, 90 of the Queensland Fisheries Act 1994 regulate possession transport and release of non-indigenous fishes and noxious fishes. Glossolepis leggetti is not listed on this schedule as noxious fish. Noxious fishes are listed in section 74 of the Queensland Fisheries Act 1994, Fisheries (Freshwater) Management Plan 1999 and Glossolepis leggetti is not recorded on that list as a noxious species. http://www.legislation.qld.gov.au/acts_sls/acts_sl.htm 8.4 Western Australian Government Under Regulation 176 of the Fish Resources Management Regulations 1995, a person must not bring into the State a species of fish not endemic to the State without the written approval, or written authority, of the Executive Director of the Department of Fisheries. Species listed as noxious under Schedule 5 of the Fish Resources Management Regulations 1995 and prohibited to be imported into the State. Glossolepis leggetti is not listed as noxious or restricted in Western Australia. Fish Resources Management Regulations 1995 http://www.slp.wa.gov.au/legislation/statutes.nsf/default.html 8.5 The South Australian Government Section 49 of the Fisheries Act 1982 makes it an offence to import or sell exotic fish. The South Australian Fisheries regulations relating to exotic aquarium fish are the Fisheries (Exotic Fish, Fish Farming And Fish Diseases) Regulations 2000, Regulations Under The Fisheries Act 1982. Part 6 of the regulations creates schedule 3 that lists the fishes exempt from Section 49 of the fisheries Act. 8.6 The New South Wales Government New South Wales Fisheries Management Act 1994 No 38 sections 209, 210 and 211 declare certain fish and plants to be noxious and it is an offence to possess or sell noxious fish. Section 217 controls the importation of live fishes into the state. Section 340 of the New South Wales Fisheries Management (General) Regulations 2002 declares certain fish, aquatic invertebrates and plants to be noxious. Glossolepis leggetti is not listed as noxious in this Regulation. 8.7 The Victorian Government Section 75 of the Victorian Fisheries Act 1995, allows the declaration of certain species as "Noxious Aquatic Species". The Department of Natural Resources and the Environment publishes the Noxious Aquatic Species List on their web site. Glossolepis leggetti does not appear on this list. The list is available on the World Wide Web at universal resource locator http://www.austlii.edu.au/au/legis/vic/consol_act/ 10. Assess the likelihood that the species could establish a breeding population in the Australian environment should it ever be released from effective human control. The latest risk assessment process for estimating the ability of a fish species establishing within the Australian environment was prepared by Mary Bomford in 2006 Using the provisions in “Risk assessment for the establishment of exotic vertebrates in Australia: recalibration and refinement of models” A report produced for the Department of the Environment and Heritage, Commonwealth of Australia 2006 Using the copy of Climex for PC provided to the Author by Mary Bomfpord the following calculations were done to provide a score against the provisions in the assessment process.
The score of 8 according to the assessment model gives the fish a moderate chance of establishment. Establishment Risk Rank Establishment Risk Score Extreme 13 Very High 11–12 High 9–10 Moderate 6–8 Low 4–5
Very Low ≤ 3 11. Provide a comprehensive assessment of the potential impact of the species should it establish feral population/s in Australia. Include, but do not restrict your assessment to the impact of this species on: • similar niche species (ie. competition with other species for food, shelter etc.) • probable prey/food sources • habitat and local environmental conditions. 11.1 Likelihood of Establishment following “escape” If this species were to escape from effective control into a natural location where climate would enable it to survive it will most likely be limited to North Queensland, North of Western Australia and Northern Territory. There is very little of Australia’s climate that matches that of the natural origin in Irian Jaya. (See Climex calculations attached to Reference section Appendix A.) Glossolepis leggetti has a small distribution in North Western Irian Jaya restricted to the Wapogo River system and its tributaries. The natural spread of this species would occur similar to other rainbowfishes. Some of the spread mechanisms for rainbowfishes are upstream and downstream migrations especially in times of greater flow during wet season floods. Barriers such as waterfalls will prevent upstream migrations of rainbowfishes and the marine environment is devoid of rainbowfishes so the estuaries of rivers prevent rainbowfishes from moving to new rivers via the sea (Allen 1995). The most likely areas where the fish would establish are where the suitable climate is adjacent areas of more dense population ,where the likelihood of accidental or intentional release is greater. Possible areas may include areas such as Townsville to Cairns, Queensland and the areas adjacent Darwin in the Northern Territory. The likely hood of escaping effective human control in the Kimberley region of WA is reduced because of the low population density. Since the most likely scenario for release into the wild will be by aquarium escape into the disturbed habitats surrounding major centres of population the survival of this species is extremely unlikely. Even if somebody was prepared to transport expensive broodstock (plastic bags, oxygen, styrofoam boxes etc) to one of the possible suitable natural habitats (e.g. Lake Argyle in W.A. or Lawn Hill Gorge National Park in Queensland) and these conspicuous pink and grey fish were to avoid the formidable spectrum of natural predators ( an array of waterbirds, an even larger array of predatory fish such as barramundi, grunters etc, file snakes, and so on) and the species became established it is most likely that it would peacefully co-exist with the other small forage species there just as several species of native rainbowfishes, glassfishes, hardyheads and small gudgeons peacefully co-exist in many other habitats in Northern Australia. The naturally restricted habitat of G. leggetti tends to suggest its behaviour is that of low invasiveness because it is not already widespread despite suitable habitat surrounding its natural distribution. It is also possible that locally predators in that area are efficient in controlling its numbers and reducing its spread into adjacent habitats. Glossolepis have no demonstrated salt tolerance therefore no tendency to invade other drainages via estuary migration (Allen and Cross 1982, Allen 1989, Allen 1991, Allen 1995, Allen et al 2002, Herbert and Peeters 1995, Lake 1978, Larson and Martin 1990, Leggett and Merrick 1987, Lever 1996, Merrick and Schmida 1984).
It can be assumed that because Glossolepis leggetti is similar to and is most closely related to Glossolepis multisquamatus and other members of the Glossolepis genus the behaviour will be similar. No aquarium observations of Glososlepis leggettii have been recorded but other closely related fish from this genera are mid to surface dwellers, exhibiting little aggression toward other fish except from breeding males and this aggression is stylized display that is harmless and generally ignored by fishes of other species and mostly ignored by their own species except other males trying to attract available females (D Wilson pers obs). 11.3 Probable Prey/Food sources Generally rainbowfishes are omnivorous eating mainly algae which they scrape from harder surfaces with their villiform teeth that extend to the outside of the jaws. They will also take advantage of small crustaceans, aquatic and terrestrial insects when available Leggett’s Rainbowfish Glossolepis leggettii is a small omnivore, a second order consumer that itself would form part of the diet of larger predatory fishes. It is a relatively small species with a maximum recorded length of 92 mm (Allan & Renyaan 1998). The predators in the Wapago River System recorded by Allen an Renyaan (1998) are fishes from the genus Anguilla, Arius, Neosilurus, Hephaestus, Mesopristes, Glossamia, Lutjanus, Toxetes, Glossogobius, Belanobranchus, Butis, Eleotris, Mogurnda, Opheleotris, and Prionobutis are similar but less in number than the predators in the undisturbed habitats in the North of Australia. 11.4 Impact on Habitat and Local Environmental Conditions Glossolepis leggetti are mid water swimmer and thus cause no disturbance to the substrate or cause water turbidity. Their dietary components (algae and aquatic organisms) are essentially unlimited in any healthy ecosystem. This species breeds by laying eggs on aquatic vegetation or debris and does not damage the habitat doing so. They exhibit no parental care so have no extra biological advantage over other rainbowfish or other egg laying species. The introduction of disease from the introduction of a Glossolepis sp. into the natural environment is unlikely to pose any further risk than other endemic freshwater fish species as there are no known fish diseases or strains specific to Melanotaeniids. Any diseases that are carried into native waters by escaped G. leggetti (Fishbase records diseases in other Glossolepis species such as fin rot, flukes and general bacterial infections) are unlikely to be more lethal to Australian rainbowfishes than would diseases they may already by carrying. In particular, with Mycobacteriosis, a common captive disease of rainbowfish worldwide, there is no Mycobacterium species specific to melanotaeniids (ANGFA, 2002). Kahn et al. (1999) stated that mycobacteriosis equally affects a wide range of freshwater and marine aquarium fish in Australia. There is no firm evidence, from all of the areas where other Glossolepis, e.g. G. incisus, are raised, that it has formed or will form feral populations. In the unlikely event that it would in northern Australia, those populations would be more likely to be under pressure from native Australian aquatic predators than would populations of other small exotic fishes (such as those of guppies and swordtails which are a permitted import to Australia and have formed feral populations) because their habits would be more 'familiar' to predators. 12. What conditions or restrictions, if any, could be applied to the import of the species to reduce any potential for negative environmental impacts (e.g. single sex imports). Arthington et al. (1999) considered that there is a low or residual probability that New Guinea rainbowfishes would establish feral populations in Australia. Indeed, G. incisus has been here, and popular, for more than 25 years (and other New Guinea rainbowfishes are cultivated here also). Permitting G. leggetti into Australia would not create undue pressure on the populations in the Wapagoa River system as all stocks would come initially from German breeders and then from commercial facilities to which these captive bred stocks are distributed. Further demand from the Wapagoa River system would be unnecessary once captive stocks are established as ease of supply would be greater from these sources (as it would be very difficult to form an aquarium fish exporting business in West Papua). G. leggetti poses no greater threat to Australian aquatic biodiversity than does the other Glossolepis sp. (G. incisus) currently permitted for import. The distinctive colouration of this species, likely popularity of this species among hobbyists, and expectant relatively high price should together mitigate against any likelihood of accidental establishment of feral populations. It is unknown wether this species has any distinctive features that would make it readily identifiable at a small size, rainbowfish fry at 10 millimeters are relatively difficult to differentiate to a species level. It is therefore recommended that any importation of these fish should be a minimum length of 4 centimeters for ease of identification. As it is planned that species is to be imported via a commercial facility in Europe and then distributed via a commercial facility in Australia it may be difficult to control the distribution and abundance of the species once established in Australia. The establishment of a permit system would not be feasible on an individual fish basis as it would require coordination of permits from the wholesaler, to the individual retailer and then on to the individual purchaser, certainly crossing state boundaries in the process. It may be possible to affect a permit type system on specified individual wholesalers allowing them alone to import and distribute the fish species, thus controlling the number of sources of this species once they enter Australia. Retailers/traders should be encouraged to engage in "best practice" and to provide relevant information brochures to buyers of this species. Once initial stocks of this fish species have been established in the hands of private aquarists (for example over a 5 year period), the permit system may then be scaled down or deleted. At present, there are numerous Melanotaeniid species being kept in Australia that have been derived from very small numbers of fish, imported pre-1986 (when ideal breeding techniques were still being developed) and surviving despite very narrow genetic variability. The genetic basis of this species will be considerably wider and thus the need for “fresh” wild stock imports at a later date will be unlikely. Importation of single sex or reproductively altered individuals would not be of any value to the recipient aquarist and would be counterproductive to the goals of ANGFA and its members. It is considered that Glossolepis leggetti should be approved for importation into Australia via the proposed channels outlined in this document. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||