© Baker, J.L. (2009) Marine Species of Conservation Concern in South Australia Full citation Baker, J.L. (2009) Marine Species of Conservation Concern in South Australia: Volume 1 - Bony and Cartilaginous Fishes. Report for the South Australian Working Group for Marine Species of Conservation Concern. J. Baker (consultant); Science and Conservation Division, and Coast and Marine Conservation branches of S.A. Department for Environment and Heritage (DEH); Marine and Coastal Community Network of S.A. (MCCN), and Threatened Species Network (TSN). Web version published by Reef Watch, South Australia.

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White-barred Boxfish / Humpty Dumpty

Family Name:	Aracanidae (or Ostraciidae, sub-family Aracaninae)
Scientific Name:	Anoplocapros lenticularis (Richardson, 1841)
Recommended Status in S.A:	Data Deficient
Rationale:  The White-barred Boxfish is included here because the species is not commonly recorded in South Australia, other than in bycatch from the Great Australian Bight, and occasional sightings by divers in more central parts of S.A.; (ii) generally, temperate boxfishes are strongly site-associated / territorial and haremic, characteristics that can increase the vulnerability of populations to localised impacts; (iii) the species is part of the bycatch in a number of trawl fisheries, and trawl-caught specimens are unlikely to survive; (iv) there is a growing, specialist aquarium trade for Australian boxfishes, including this species, and potential impacts on populations apparently have not been investigated;  and (v) there is little existing information about the biology, population dynamics, or relative abundance of this species across its range.

Page Contents

Current Conservation Status

No listings known

Distribution

Southern Australia

The species occurs across southern Australia, reportedly from Victoria (west of Lorne), through to W.A. (with Dongara as the western limit) (Hutchins and Swainston, 1986; Kuiter, in Gomon et al., 1994).
The species is rarely recorded in various bays and around islands in southwestern W.A., with examples including King George Sound and Princess Royal Harbour, and various islands in the Recherche Archipelago (e.g. Hutchins, 2005; WA Museum data, 2006).

South Australia

Examples of records of White-barred Boxfish in South Australia include: deep waters at the edge of the continental shelf in the central Great Australian Bight; the Nuyts Archipelago islands, and shallow bays of the far west coast / eastern Great Australian Bight; the Investigator Group islands, Flinders I., and the Anxious Bay region (all in the south-eastern Great Australian Bight); deep waters off the southern tip of Eyre Peninsula; southern Yorke Peninsula (including locations around the “heel”, such as Troubridge Point and Edithburgh Jetty, and also the “toe”, such as Innes National Park coastal area); northern Kangaroo Island (e.g. Stokes Bay and Western River Cove); north-eastern Kangaroo Island; southern Kangaroo Island (including a beachwash record); southern Fleurieu Peninsula (e.g. Normanville, Rapid Bay and other areas); Encounter Bay (e.g. The Bluff, and Wright I.); north-east Kangaroo Island (e.g. Kingscote, and Hog Bay area), and deep waters east of the Dudley Peninsula / south of Encounter Bay (Kuiter, 1983; Branden et al., 1986; Hutchins and Swainston, 1986; University of British Columbia Fish Museum records, cited in Anon., 1996; Australian Museum, 2004i; photograph by D. Harasti, undated; D. Muirhead, MLSSA, pers. comm., 2005, 2006; K. Smith, Reef Watch, unpubl. data 2002-2004; Edgar et al., 2006; Australian Museum and SA Museum records, cited in OZCAM database, 2007).

Habitat

The species is found on “clear, coastal rocky reefs with algae”, or “low vegetated reefs” (Kuiter, 1996a), on the continental shelf. White-barred Boxfish is reported to be moderately common near coastal reefs and jetty pylons in some parts of the range (Edgar, 2000). Juveniles have been observed below overhanging ledges, with sponges (Kuiter, 1996a), and have rarely been observed in waters less than 10m (B. Hutchins, W.A. museum, pers. comm., 2007). In some areas, adults, especially large males, swim about more openly, in similar reef habitat to the young, and are often found deep inside large caves (Kuiter, 1996a). Recreational divers in W.A. have also recorded the species in caves (e.g. at Rottnest Island). The species has also been recorded in mixed reef / sand habitat (SA Museum record).
Hutchins (in Hutchins and Swainston, 1986) reported that the species is occasionally seen on offshore reefs of southern Western Australia. In southwestern W.A., the species has been recorded on reefs, and also in other habitats (e.g. surveyed by bottom trawl / dredge) (Hutchins, 2005). During a recent survey of fish habitats in the shallow subtidal in south-western W.A., the species was recorded on reefs covered with macroalgae of medium density (Harvey et al., 2004).
The White-barred Boxfish is taken as bycatch in trawls (Hutchins and Swainston, 1986; Kuiter, in Gomon et al., 1994; Edgar, 2000), particularly in the Great Australian Bight (GAB), where it is considered to be more numerous than on coastal reefs (Hutchins and Swainston, 1986). The regularity of records in trawl bycatch may indicate that a substantial number of individuals occur in open water habitat away from the home reefs (i.e. given that trawlers in the GAB area do not normally operate over shallow reef).
The depth distribution of published records for this species range from shallow bays to deep offshore waters in the Commonwealth jurisdiction.  The species’ depth range is between about 10m and 250m (B. Hutchins, W.A. Museum, pers. comm., 2007), with the lower depth limit based on trawl records from deeper waters of the GAB. There are various records in Australian museums of specimens from the edge of the continental shelf, and upper continental slope waters. May and Maxwell (1986, cited in Froese and Pauly, 2007) reported the lower depth limit as 220m.

Notes on the Biology and Behaviour

Growth

The species grows to about 33cm (May and Maxwell, 1986, cited in Froese and Pauly, 2007; B. Hutchins, W.A. Museum, pers. comm., 2007).
Maximum sizes recorded include 0.68kg (New South Wales Fishing Clubs Association; Australian Anglers Association Records Authority, 2003); and 0.54kg, for a specimen taken in W.A. (Hutchins and Swainston, 1986; Australian Anglers Association, W.A. Division, 2002a).

Diet

In general, boxfishes are benthic feeders (Kuiter, 1996a) that eat small sessile invertebrates (such as small crustaceans), and algae (Nelson, 1994, cited in Froese and Pauly, 2007). Juveniles have been recorded picking at fishers’ baits.

Reproduction

According to Kuiter (2000), temperate boxfishes are protogynous hermaphrodites, and when in captivity, females of some species in the Aracanidae have been observed transforming into males.

Behaviour

In general, boxfishes are territorial and haremic (Nelson, 1994, cited in Froese and Pauly, 2007); however specific information on the family structure and population dynamics of A. lenticularis is not available.

Other Notes on the Biology

The males and females differ in colour, body shape, and markings. Males are more rounded; darker orange/red to red/brown colour, with several broad white or grey-white stripes. Juveniles and females have a straighter dorsal profile, and are lighter orange than males, with several irregular black lines amongst the white body stripes (Hutchins and Swainston, 1986; Kuiter, in Gomon et al., 1994; Kuiter, 1996a).
White-barred Boxfish is considered poisonous (Hutchins and Swainston, 1986), due to the presence of the mucous toxin ostracitoxin, which is secreted from boxfishes when they are under stress (Kuiter, in Gomon et al., 1994).

Fisheries Information

Commercial Fishing and Trade Information

White-barred Boxfish form a part of the bycatch in the Commonwealth-managed Southern and Eastern Scalefish and Shark Fisheries (SESSF) (AFMA, 2002a). According to Bromhead and Bolton (2005), the species is part of the discarded bycatch in the South East Trawl Fishery.
The White-barred Boxfish is part of the trawl bycatch in the Great Australian Bight (Hutchins and Swainston, 1986; Kuiter, in Gomon et al., 1994). In the GAB Trawl Fishery, bycatch sampling in 2000 and 2001 (Brown and Knuckey, 2002) showed that Anoplocapros lenticularis was observed in 43 of the 209 trawl shots; the average quantity discarded was 1.9kg per trawl shot (Brown and Knuckey, 2002).
The species has also been recorded in the bycatch of prawn trawlers operating on the west coast of S.A., seaward of Venus Bay and Anxious Bay (South Australian Museum records, cited in OZCAM database, 2004).
Boxfish species are caught in small numbers and discarded, as part of the bycatch in the W.A. temperate demersal gillnet and demersal long-line fisheries (McAuley and Simpfendorfer, 2003).
White-barred Boxfish is used in the aquarium fish trade; however the extent to which the species is collected in South Australia for this purpose, is not known for this report. The White-barred Boxfish is amongst the top 40 of about 250 fish species taken commercially in W.A. for the aquarium trade. Since 1976, around 4,302 Humpback Boxfish (= White-barred Boxfish) have been taken by this fishery (W.A. Department of Fisheries, 2004b). Between the years 2000 and 2003, a reported 465 specimens of A. lenticularis per year were collected in W.A. for the aquarium trade (W.A. Department of Fisheries, 2004b).
Specimens of A. lenticularis are exported to the U.S., where the species is called the Barred Cowfish, Australian Cow-Chow Boxfish, Flame Trunkfish / Flame Boxfish, White-barred Trunkfish / Red-White Barred Trunkfish by some aquarists. The species also appears in aquariums in Japan and other countries. The costs of exporting and importing Australian boxfishes are high, hence few are readily available on the international market, and such fish are sold for high prices. The export price from Australia in 2005 ranged from $US100 – 125 for males, and $US35 – 75 for females; and $US250 for a pair (Ryan and Clarke, 2005). In 2004 - 2006, one American distributor was selling small specimens for US$900 - US$945, with slightly higher prices for larger specimens. Various supply companies in the US were selling A. lenticularis for around $1000 per fish in 2004, and $US550 per fish in 2006-2008. The species was included in the list of “rare and unusual fish” for aquariums, and the species was one for which there was a waiting list for available specimens. During the early 2000s, a company in Florida that was selling this species as part of their “advanced aquarist” supply, considered A. lenticularis to be a “poor shipper” that does not travel well during the export / import process, and does not meet the “95% shipping survival criteria”, hence no guarantees are supplied regarding the fish being alive on arrival at the U.S. destination.

Recreational Fishing

Although White-barred Boxfish is not usually targeted, there are records of the species being taken by anglers, and some clubs record the maximum sizes caught (e.g. New South Wales Fishing Clubs Association, 2003; Australian Anglers Association W.A. Division, 2002a; Australian Anglers Association Records Authority, 2003).

Vulnerable Characteristics of the Species and Threatening Processes

Based on published observations, it appears that at least some life stages of the species (e.g. juveniles) are strongly site-associated with reefs and caves, which could make some populations vulnerable to localised and site-specific impacts.
In general, boxfishes are strongly site-associated, territorial, haremic species, characteristics that can increase their vulnerability to site-specific impacts.
Threatening processes are not well known for this species; however its bycatch during trawling would appear to be a main source of mortality. The White-barred Boxfish A. lenticularis is recorded as bycatch in fish trawls (e.g. GAB) and prawn trawls (west coast) in South Australia. In New South Wales the closely related species A. inermis (Eastern Smooth Boxfish) is a very commonly caught bycatch species in the fish and prawn trawl fisheries in estuaries and in deeper waters on the continental shelf (Gray and Kennelly, 2001; N.S.W. Department of Primary Industries, 2004; Wayte et al., 2004). Studies have shown that the Eastern Smooth Boxfish suffers barotrauma when hauled in trawls, and A. inermis was classified overall as a “high risk” species in terms of population impacts from trawl fishing (see N.S.W. Department of Primary Industries, 2004).
Removal from the wild for the international aquarium trade is an additional source of mortality. A number of aquarium supply companies overseas obtain A. lenticularis specimens from Western Australia; however information is lacking on the extent of this practice in South Australia. There has been no assessment of the sustainability of the catch for the aquarium industry.

Research Requirements

More information is required on the distribution (particularly in South Australia) and abundance of this species, and its habitat in deeper waters. The full depth range is not well known, and there is considerable discrepancy in published sources. The life history is also not well known, and information on the habits, possible spatial segregation of sexes and/or life stages, and reproductive cycle (including the possible existence of haremic groups) may also assist in managing potential impacts on this species.
There has been no assessment of the population impacts / sustainability of the capture of A. lenticularis (as trawl bycatch, and as a target species taken by divers, for the aquarium industry).

Management Requirements

Pending the results of population and fisheries assessments, methods may need to be devised to limit the bycatch of this species.
All reef fish species taken for the aquarium trade should be documented over space and time, and sustainability assessments should be undertaken. The potential for illegal collecting of this species should also be monitored and prevented.

Other Information

The White-barred Boxfish is a popular fish for divers and marine photographers, and is also promoted internationally as a species observable during dive tours in Western Australia.