Tasmanian Waters Research Articles

Molecular provenance analysis for shy and white-capped albatrosses killed by fisheries interactions in Australia, New Zealand, and South Africa

Shy and white-capped albatrosses, Thalassarche cauta and T. steadi, respectively, are phenotypically similar and are known to suffer fisheries-related bycatch mortality across their foraging range. Assessments of the extent or scale of impact of bycatch mortality on these species have previously been precluded by difficulties identifying bycatch carcasses to species level. In this study, a fast and simple molecular test based on a single nucleotide polymorphism in mtDNA of shy and white-capped albatrosses was used to determine the species composition of fisheries bycatch carcasses recovered from Australian, New Zealand, and South African waters. The only area where bycatch mortality of both species co-occurred was in Tasmanian waters; in all other zones the bycatch was exclusively comprised of white-capped albatrosses. Genotypic provenance assignment tests of shy albatrosses, a species with significant genetic structure between island colonies, correctly assigned 72% to their island of origin. These data are the first to provide insight into the relative vulnerability of shy and white-capped albatrosses to bycatch mortality across their foraging range, and to establish the vast differences in the at-sea distributions of these two species.

A revision of the Iblidae and the stalked barnacles (Crustacea: Cirripedia: Thoracica), including new ordinal, familial and generic taxa, and two new species from New Zealand and Tasmanian waters

The discovery of two diminutive and very distinct ibliform barnacles from shallow waters off northern New Zealand and northeastern Tasmania provides an opportunity to re-evaluate the Iblidae, the most primitive of the living thoracicans. These are retained within the Superorder Thoracica, but are distinguished at ordinal level from the remainder of the Pedunculata s.l. The resultant new order, the Ibliformes nov., comprises barnacles with predominantly chitinous rather than calcareous capitular plates; two families are recognized, the Iblidae s.s., comprising two subfamilies, the Iblinae (Ibla s.s.) and the Neoiblinae nov. (Neoibla gen. nov.), and the Idioiblidae nov. comprising the Idioiblinae nov. (Idioibla gen. nov.) and the Chaetolepadinae nov. (Chaetolepas Studer, 1889 and Chitinolepas gen. nov.). The monotypic Chitinolepas further highlights the high endemism and relict nature of the New Zealand marine fauna in particular and the southern hemisphere in general. On the basis of morphology and, where possible, genetic and larval work, it is recommended that the remainder of the stalked thoracicans be divided between three new orders, the †Cyprilepadiformes, Ibliformes, Lepadiformes and Scalpelliformes.

Scale-bearing nanoflagellates from southern Tasmanian coastal waters, Australia. II. Species of Chrysophyceae (Chrysophyta), Prymnesiophyceae (Haptophyta, excluding Chrysochromulina) and Prasinophyceae (Chlorophyta)

Twenty-eight species of scale-bearing nanoflagellates from southern Tasmanian waters are illustrated and discussed (excluding the haptophyte Chrysochromulina, previously reported (LeRoi and Hallegraeff 2004), and coccolithophorids). Scale morphologies of both field samples and enrichment cultures were examined using transmission electron microscopy. Predominant species included the chrysophyte Paraphysomonas imperforata, the prasinophyte Pyramimonas grossii, and haptophytes Phaeocystis globosa and Imantonia rotunda. There were nine new records for Australian waters: the chrysophytes Chrysolepidomonas marina, Paraphysomomas antarctica, P. bandaiensis, P. foraminifera, P. cf. takahashii, Petasaria heterolepis, Thaumatomastix cf. thomsenii, and the prasinophytes Dolichomastix cf. tenuilepis and Mamiella gilva. Two potentially harmful haptophyte species, Phaeocystis globosa and Prymnesium parvum f. patelliferum, responsible for bloom events and fish mortalities, particularly in the northern hemisphere, were also found. The present survey adds further evidence for the apparent cosmopolitanism of many scale-bearing nanoflagellate species. © 2006 by Walter de Gruyter.

Catchment characteristics and chemical limnology of small lakes, tarns and mire pools in New Zealand (South Island) and Tasmania

Small alpine water bodies can play a large role in defining patterns of biological and landscape diversity, and may be particularly sensitive to climate change. A large limnological dataset, consisting of 65 and 6 water bodies, respectively, on South Island and Stewart Island (New Zealand) and 76 and 12 water bodies, respectively, in the Tasmanian highlands and coastal areas (Australia), was constructed to assess patterns of variation in alpine and subalpine lakes in the Australasian region. With the exception of the coastal systems, most lakes were very dilute. In general, lake water chemistry resembled world average seawater cationic ratios (WASW). In addition, some New Zealand lakes fell close to the world average freshwater cationic ratios (WAFW), due to relatively high calcium concentrations, and some were dominated by magnesium due to the presence of serpentine bedrock in the catchment area. Multivariate analyses of the joint dataset revealed that the variation in chemical limnological variables was dominated by gradients in conductivity, pH and gilvin. The concurrent relationships between pH, calcium and gilvin, which enabled the differentiation of Tasmanian water bodies into limnological provinces, were absent in New Zealand. In the latter, pH and gilvin contents were not coincident, as clear-water acidic systems occurred in New Zealand. The higher diversity of freshwater bodies in New Zealand will enable independent assessment of the effects of pH and gilvin on the distribution and diversity of biota.

Predation of trap-caught southern rock lobsters, Jasus edwardsii (Hutton, 1875), in Tasmanian waters by the Maori octopus, Octopus maorum (Hutton, 1880): Spatial and temporal trends

A long-term fisheries-independent data set was used to determine differences in the catch rates of the Maori octopus, Octopus maorum, and octopus-induced mortalities of southern rock lobsters, Jasus edwardsii, in lobster traps over a range of spatial and temporal (annual, seasonal and lunar cycle) scales in Tasmania, Australia. The impact of lobster catch rates on lobster mortality and octopus catch rates was also examined. Results indicated spatial variation in octopus catch rates, but no spatial variation in lobster mortality rates. No consistent annual or lunar cycle trends were evident for octopus catch rates or lobster mortality rates within the four lobster fishery assessment areas examined. An increase in octopus catch rates during summer and spring was found within all four areas, with areas 1 and 8 having a corresponding increase in lobster mortalities during these seasons. Lobster catch rates were found to have no influence on the catch rates of octopus or lobster mortalities. These results suggest that changing fishing practices over the various scales examined in this study would not be practical for minimising the impact of octopus predation on trap-caught lobsters within Tasmania. However, these results provide a fishery-independent estimate of octopus-induced within-trap mortality that will assist in future analysis of management strategies for the southern rock lobster fishery in Tasmania.

Kin recognition and adoption in mysids (Crustacea: Mysidacea)

The phenomenon of adoption, i.e. replacement of larvae prematurely liberated from the brood pouch of conspecifics, and kin recognition was examined in three mysid species found commonly in Tasmanian waters: Anisomysis mixta australis, Paramesopodopsis rufa and Tenagomysis tasmaniae. A new method for testing the incidence of adoption using fluoroscein dye, which enables the determination of ‘same stage’ adoptions, is described. Under field and laboratory conditions, all species practised intraspecific adoption into their own brood pouches. Under laboratory conditions the incidence of adoption was higher in T. tasmaniae than it was in the other two species. Tenagomysis tasmaniae also adopted its own young in preference to those of a conspecific. Differences in the incidence of adoption between the three species suggests a higher degree of maternal care in T. tasmaniae than in either A. mixta australis or P. rufa and may be explained by differences in anatomy, habitat conditions and predation pressure.

Using stable isotopes to study resource acquisition and allocation in procellariiform seabirds

Some procellariiform seabirds use a dual strategy for provisioning their chicks by alternating short (ST) and long (LT) foraging trips. Parent birds gain mass during LT but they lose mass while increasing the chick feeding frequency during ST. Self-feeding during LT is crucial for the success of ST because firstly most of the energy used during ST is likely to be derived from the energy stored during LT and secondly self-feeding during ST is presumed to be negligible. Self-feeding by adult procellariiforms is thus a key issue to understand allocation processes but it is still poorly known. We tested these predictions by using the stable isotope (delta(15)N and delta(13)C) technique on birds' plasma and prey with the short-tailed shearwater Puffinus tenuirostris breeding at Tasmania as a model. Parent shearwaters returning to the colony after a LT have an Antarctic/subantarctic delta(13)C signature in their plasma (-23.8 per thousand), thus indicating that they fed in cold waters, far away from their breeding colony, for their own maintenance. Parent birds returning to the colony after a ST also have a distant Antarctic/subantarctic delta(13)C signature in their plasma (-24.3 per thousand), thus verifying that self-feeding is negligible during ST and that birds fast at that time, using energy stores built up in cold waters. Plasma delta(15)N values of adults (8.8 per thousand) indicates they mainly prey upon zooplankton-eating organisms, probably mesopelagic myctophid fishes. A simple isotopic mixing model estimates that they consume by mass 87% myctophids and 13% subantarctic krill when self-feeding. Finally and as expected, the carbon isotopic signature of chick plasma (-22.2 per thousand) was intermediate between those of high- and low-latitude marine organisms and is thus in agreement with chicks being fed with a large diversity of prey species caught by adult birds from Antarctic to Tasmanian waters. One main consequence of this system is that reproduction of a Tasmanian species is controlled by resources available at great distances from the breeding colony that drive allocation decisions of parent birds.

Sanguinicola maritimus n. sp. (Digenea: Sanguinicolidae) from Labridae (Teleostei: Perciformes) of southern Australian waters

A new species of Sanguinicola Plehn, 1905 is described from the marine teleosts Notolabrus parilus (Richardson) and N. tetricus (Richardson) (Perciformes: Labridae) from Western Australian and Tasmanian waters. This host distribution is strikingly anomalous; however, the present material fulfils the morphological criteria of Sanguinicola. S. maritimus n. sp. differs from previously described species in having the combination of a body 1,432--1,701 mum long, the oesophagus 18.3--21.7% of the body length, the testis occupying 42.8--52.3% of the body length, an oviducal seminal receptacle and Mehlis' gland present, ovoid eggs, and vitelline follicles that extend anteriorly past the nerve commissure, laterally past the lateral nerve chords and posteriorly to the anterior margin of the cirrus-sac. S. maritimus also lacks a protrusible anterior proboscis. It also differs in the combination of host and geographical location, being the first Sanguinicola species from a marine teleost and the first from Australian waters.

New and little-known species of Didemnidae (Ascidiacea, Tunicata) from Australia (part 2)

Eighteen new species of Didemnidae are included in the 71 species discussed. Two hundred and forty-one species of this family now are known from around the Australian continent. Newly recorded material is from the Western Australian Museum (principally from north-western Australia), the South Australian Museum (from Kangaroo I. and Tasmanian waters) and the Queensland Museum (from Darwin and the Northern Territory). Many of the species recorded from north-western, north-eastern and the north of Australia have a range that extends into the western Pacific and sometimes the western Indian Ocean. Tropical didemnid species seldom extend into temperate Australian waters, where the species are largely indigenous. The genus Didemnum dominates the fauna in both tropical and temperate waters. Of the new species, half are in the genus Polysyncraton (five tropical and four temperate species), four are Lissoclinum spp., two are described in each of the genera Didemnum and Leptoclinides, and one in the genus Diplosoma. Spicules are confirmed as reliable, genetically controlled characters showing little intraspecific variation. Amongst the known species, the unusual colonial organization reported for Leptoclinides glauerti Michaelsen, 1930, with its atrial apertures opening directly on the under surface of the colony, is confirmed. Originally described from a single mutilated part of a colony, the species has been redescribed, and its status in the genus Atriolum validated. Trididemnum pseudodiplosoma (Kott, 1962), formerly known only from South Australia, is found to extend into tropical waters of the Northern Territory and the Coral Sea; and Didemnum incanum (Herdman, 1899) appears to be one of the few known species with a trans-Tasman range.

The Caprellidea (Crustacea: Amphipoda) from Tasmania

The taxonomy of the Caprellidea from the Tasmanian coast is reviewed with data on species composition and biogeographical characteristics. Four new species, Caprella edgari n. sp., Hircella inermis n. sp., Orthoprotella tuberculata n. sp. and Paraproto tasmaniensis n. sp. are described, and detailed descriptions of Caprella acanthogaster Mayer, 1890, Orthoprotella tasmaniensis Guiler, 1954 and Paraproto spinosa (Haswell, 1885) are provided. Lateral view figures of the 18 species found in Tasmanian waters until now, with a key to species level, are also given. The species diversity of littoral caprellids from Tasmania is considerably high when compared with other regions of similar latitude in the southern hemisphere, probably due to the warm effect of the East Australian current passing down towards the east coast of Tasmania. This fact, with previous studies on the low concentrations of dissolved nutrients in rivers and dark tannin-stained waters on the west coast, could result in species richness and abundance being clearly higher on the east coast of Tasmania.

Scale-bearing nanoflagellates from southern Tasmanian coastal waters, Australia. I. Species of the genus Chrysochromulina (Haptophyta)

A comprehensive taxonomic survey of Chrysochromulina was undertaken in 52 samples from southern Tasmanian coastal waters. Scale morphology of both field samples and enrichment cultures was examined using transmission electron microscopy. Twenty-eight known species of Chrysochromulina were recorded. These included C. adriatica, C. alifera, C. apheles, C. brevifilum, C. chiton, C. cyathophora, C. ephippium, C. ericina, C. hirta, C. leadbeateri, C. mantoniae, C. minor, C. novae-zelandiae, C. pachycylindra, C. parkeae, C. polylepis, C. pringsheimii, C. pyramidosa, C. simplex, C. spinifera, and Chrysochromulina sp. (eyelash). There were seven new records for Australian waters: C. acantha, C. aff. brachycylindra, C. aff. camella, C. fragaria, C. mactra, C. scutellum and C. aff vexillifera. All species, except C. novae-zelandiae, had been previously reported from the northern hemisphere. A further nine undescribed species are documented. However, lack of complete cells prevented new species descriptions. Two known toxic species, Chysochromulina polylepis and C. leadbeateri, responsible for massive fish kills in Scandinavia, were found in this survey. Toxicity testing of six Chrysochromulina species isolated from Tasmanian waters (C. acantha, C. apheles, C. hirta, C. scutellum, C. simplex, Chrysochromulina sp. [eyelash]) was undertaken, using larval brine shrimp (Artemia) bioassays. None of the strains tested was found to be toxic.

Australian fur seals (Arctocephalus pusillus doriferus) breeding in Tasmania: population size and status

This study confirms the persistence of five major breeding colonies of Australian fur seals (Arctocephalus pusillus doriferus) in Tasmanian Bass Strait waters. Incidental births also occasionally occur in very low numbers at other sites. Data collected between 1989 and 1999 shows that estimates of the minimum number of pups born at the major colonies varies considerably between sites and years. No colony has shown a consistent trend in pup production over the last 11 seasons. The most recent count for all Tasmanian colonies for the 1999 breeding season provided a minimum estimate of 3254 pups produced, similar to the estimate of 3373 in 1989. The highest estimate was recorded in 1995 when at least 6024 pups were born. Combining the most recent counts with the numbers estimated for the four Victorian colonies (13 872) gives a minimum pup production of 17 126 for the species, with only one-fifth of all pups being born on Tasmanian islands. Application of population estimators to translate pup numbers to population size for the species results in a conservative estimate of 68 500 individuals with upper and lower bounds of 60 000 and 77 000 Australian fur seals. Numbers of Australian fur seals remain low relative to other fur seal populations, with Australian fur seals being less numerous by an order of magnitude compared with their South African counterpart (A. p. pusillus). The current estimate of the total population of Australian fur seals is approximately half that of pre-sealing levels. The current number of breeding colonies in Tasmania indicates that the population of Australian fur seals breeding in Tasmanian waters has stabilised at well below their historic pre-sealing levels, with at least four sites remaining vacant. The species remains vulnerable due to its small population size, with Tasmanian breeding colonies being particularly vulnerable because of low numbers and due to the profound influence of weather events on pup survival.

Biffarius pacificus, a new species of the Callianassidae (Crustacea: Decapoda: Thalassinidea) from northern Chile

Nine specimens of Biffarius pacificus sp. nov. were collected with a van Veen grab at two sublittoral stations off the northern coast of Chile (Iquique, 22o12'S; Patache, 22o45'S) at depths ranging from 17 to 30 m. This is the first record of the genus Biffarius from the southeastern Pacific Ocean off South America. Biffarius pacificus sp. nov. is closely allied to B. poorei from Tasmanian waters. A detailed differentiation of both species is provided.

Validation of age and growth estimates using thin otolith sections from the purple wrasse, Notolabrus fucicola

The age of Notolabrus fucicola from the east and southeast coasts of Tasmania was estimated from counts of opaque (transmitted light) growth zones in thin transverse sections of sagittal otoliths. The position of the first annulus was validated through the otolith radii of known-age juveniles. Marginal increment analysis was performed by examining the growing edge of otoliths over 2 years. This showed that opaque zones were formed annually and were consistently deposited from late September to early December (spring season), which is coincident with annual increases in somatic growth and water temperature during this season. A criterion was developed to ensure accurate age estimation for individuals sampled during the time of year when deposition of opaque material was incomplete or not apparent. The maximum age estimated was 20 years and the relationship between fork length and age was described by the von Bertalanffy growth function (L∞ = 368 mm, K = 0.116 and t0 = –1.87 for males and L∞ = 385.7 mm, K = 0.109 and t0 = –1.96 for females). The clarity of increment structure and rigorous validation protocol that was adopted minimised the risks associated with using marginal increment analysis to validate the periodicity of increment formation and it provided robust age and growth estimates for N. fucicola in Tasmanian waters.

THREE MASS STRANDINGS OF SPERM WHALES (PHYSETER MACROCEPHALUS) IN SOUTHERN AUSTRALIAN WATERS

AbstractOne hundred and fifteen sperm whales (97 female, 15 male, 3 unknown sex) were involved in three mass stranding events during the month of February 1998 along the west and northwest coastlines of Tasmania, Australia. Sixty‐six of these whales stranded at Ocean Beach, Strahan; 35 at Greens Beach, Marrawah; and 11 at Black River Beach, Stanley. The remaining whales stranded singly along the coastline. Three mass strandings of this species in such close temporal proximity have not been reported in this area before, and this is the first time that data have been comprehensively collected from complete or near‐complete groups of sperm whales from Tasmanian waters. Adult females dominated the three stranding groups. Total lengths ranged from 417 to 1,200 cm and ages ranged from 0.75 to 64 yr. Four females were lactating and four fetuses were found amongst the groups. Stomach contents were dominated by pelagic cephalopods.

Flexible reproductive strategies in tropical and temperate Sepioteuthis squids

A major difficulty confronting the determination of cephalopod reproductive life history is assessing over what portion of the life span an individual is reproductively mature and actively depositing eggs. This paper assesses the potential of the tropical Sepioteuthis lessoniana and two genetic types of the temperate Sepioteuthis australis, to spawn multiple batches of eggs at discrete times throughout the adult life span. This is achieved by histological examination of the ovarian gametogenic cycle and detailed morphological assessments of the reproductive system, in conjunction with other biological information. The genetic type of S. australis found at the northern limits of its Australian distribution showed evidence of a high correlation between body size and quantity of mature eggs, suggesting that eggs may be accumulating to be laid in a single batch. Although maturation was also a size-related process in S. lessoniana and Tasmanian S. australis, oviduct size was not correlated with body weight in mature females, which is indicative of multiple spawning. Further supporting evidence includes relatively low gonadosomatic indices, the heavier weight of the ovary relative to the oviduct, and the feeding activity of mature animals. Mature S. lessoniana and S. australis individuals were present at each location over very wide age and size ranges. In Tasmanian waters, there were distinct seasonal differences in the reproductive biology of S. australis. Summer-caught individuals had much higher gonadosomatic indices and may have been laying larger batches of eggs compared with winter-caught individuals. Summer-caught females also showed a negative correlation between egg size and egg number within the oviduct, suggesting that some individuals were producing fewer, larger eggs and others many smaller eggs. Evidence suggests that considerable flexibility is inherent in the reproductive strategy of both S. lessoniana and S. australis.

Lipids and nutrition of the southern rock lobster, Jasus edwardsii, from hatch to puerulus

We examined the lipid class and fatty-acid composition of the southern rock lobster, Jasus edwardsii, phyllosoma larvae and puerulus stage to improve understanding of their nutrition in relation to aquaculture. Lipid is critical in the nutrition of larval crustaceans, including lobsters. Specimens were from Tasmanian waters, Australia, and North Island, New Zealand, waters. Analyses were by TLC-FID and capillary GC and GC-MS. Phyllosoma larvae and nektonic pueruli were low in storage lipid (triacylglycerol), and phospholipid was the major lipid class. Sterol, mainly cholesterol, was the next most abundant class. The ratio of the essential omega-3 fatty acid eicosapentaenoic acid (EPA) to the omega-6 fatty acid arachidonic acid (AA) was lower in newly hatched phyllosomas (1.2–1.3) than in other phyllosomas (stages III–XI; 2.8–6.7) and pueruli (3.8). Ratios of the omega-3 fatty acid DHA (docosahexaenoic acid) to EPA were also lower in newly hatched phyllosomas (0.5) than in laterstage phyllosomas (1.5–2.1) and pueruli (1.2). We have followed up these compositional data by successfully enriching the live diet (Artemia) of early phyllosomas with AA, EPA and DHA. This dietary manipulation has achieved ratios of these key polyunsaturated fatty acids similar to those of wild phyllosomas. These findings will be of significance to the future of rock-lobster aquaculture.

The Catophragmidae: members of the basal balanomorph radiation.

The Catophragmidae are divided into the subfamilies Catophragminae, in the northern hemisphere, and Catomerinae n. subfam., in the southern hemisphere. The former includes Catophragmus and Catolasmus n. gen., and the latter, Catomerus. All of the genera are considered monotypic, but our preliminary studies suggest there may be two species of Catomerus in Australian and Tasmanian waters and two, if not three, species of Catophragmus in the Caribbean and Western-Atlantic regions. A computer-based phylogenetic analysis of relationships among basal balanomorphs and certain other barnacles that exhibit apparently more plesiomorphic grades of organization results in a fully resolved branching tree with the chionelasmatids occupying the most basal position among the balanomorphs. Waikalasma is placed in Waikalasmatidae, n. fam., and assigned to the Superorder Chionelasmatoidea

Currents of the continental shelf and upper slope of Tasmania

Satellite-tracked drifters, satellite imagery, a research vessel and moorings in the waters of Tasmania, excluding Bass Strait, revealed a southward Current, sometimes called the Zeehan Current, on the outer continental shelf of western Tasmania. The current has a peak speed in winter, when it reaches around southern Tasmania as far north as Schouten Island before veering southeastward under the influence of the East Australian Current. In summer, the Zeehan Current is weaker, while the East Australian Current is stronger and overshoots southward past Tasmania by about 200 km, entraining the Zeehan Current in the process. Off western Tasmania, well seaward of the Zeehan Current, the residence time for satellite-tracked drifters was as much as one year. More than 200 km south of Tasmania in summer there was weak flow to the west. Eleven of 13 satellite drifters released in Tasmanian waters eventually meandered eastward towards New Zealand, with a travel time of over 18 months from the time of release.

Egg and larval development of laboratory‐reared striped trumpeter latris lineata (forster in bloch and schneider 1801) (percoidei: Latridiidae) from Tasmanian waters

Description of striped trumpeter (Latris lineata (Forster in Bloch and Schneider 1801)) eggs and larvae, previously described in summary only, is provided and illustrated from laboratory‐reared material. Laboratory fertilised eggs are round, 1.26–1.44 mm diameter, with a single, pigmented oil globule 0.27–0.29 mm diameter in an unsegmented yolk. Early‐stage embryos are pigmented on trunk and tail dorso‐laterally, forming a dorsal and ventral pigment band in late‐stage embryos. Hatching occurs 7–8 days post‐fertilisation in 12°C. Larvae are 2.8–3.5 mm body length (BL) at hatching with a voluminous finfold, large yolk sac with centrally‐placed oil globule, distinct pigmentation pattern, and no head spines. Flexion occurs from 5.6 to 8.7 mm BL. Fin formation commences from 6.6 mm BL in the sequence caudal, dorsal and anal (simultaneously), pectorals and pelvics. Myomeres number 33–39. Larvae are pigmented predominantly on the head, dorsal and ventral surfaces of trunk and tail, and gut ventrally, with melanophores also on upper and lower jaws. Larvae survived to 45 days post‐fertilisation, 11.9 mm BL, with complete fin‐formation of the caudal fin only. Similarities are noted between L. lineata larvae and aplodactylid, bovichtid, cheilo‐dactylid, chironemid, sillaginid, and tetragonurid larvae. A small number of L. lineata larvae were also caught inshore and at shelf edge on the Tasmanian west coast in late winter/early spring (September/ October).