Ecology of New Zealand abalones,Haliotis species (Mollusca: Gastropoda)

The spawning season of Haliotis iris Martyn, as indicated by a gonad index and examination of ovaries, was late summer to autumn at Kaikoura, New Zealand, in 1967–68. In contrast, H. australis Gmelin spawned twice, once in the spring and again in the late summer to autumn. Both patterns are typical of haliotids. But in the 1968–69 year neither species spawned; full gonads with apparently ripe eggs were maintained through the winter of 1969. No reason for this inconsistency can be offered. Haliotis iris at Taylors Mistake, 154 km south, followed essentially the same pattern as Kaikoura H. iris through 1968, but spawned slightly in autumn 1969.

Haliotis iris first produces mature eggs when it is about 60 mm long and probably spawns substantially for the first time when it is 4 years old. Although fecundities of larger animals reached about 11 million eggs, not all of these were necessarily spawned. Haliotis australis also first produces mature eggs when it is about 60 mm long, but the age at which first spawning takes place could not be determined; maximum fecundity is about 3 million eggs. The sex ratios did not differ significantly from 1: 1 for either species.     

Ecology of New Zealand abalones,Hahotis species (Mollusca: Gastropoda)

Tagging of Haliotis iris Martyn at colonies near low water, and subsequent regular observations over 18 months, showed that significant movement tended to occur only in autumn and winter when rough seas disturbed the habitat. These movements may vary from year to year depending on sea conditions. Tn contrast, subtidal colonies dispersed more gradually, seemingly disturbed by the tagging operation and subsequent rehandling. Other colonies which were not tagged remained apparently unchanged for up to 2 years. Individuals in subtidal H. australis Gmelin colonies also did not move to any great extent over this period: this species inhabits narrow crevices and appears to be a much more active animal than H. iris, both in the field and in the laboratory. Drift and attached algae were virtually absent from the crevices inhabited by H. australis and it seems likely that the species must forage to feed. A homing mechanism may be present because many older H. australis are found in deep scars on the rocks or have characteristically worn shell edges fitting the rock of their particular site.

A 24‐hour watch on a tagged, subtidal colony of Haliotis iris at Kaikoura showed that there was very little movement diurnally, and it seems likely that feeding is passive; drift algae are available at most times. No evidence of homing behaviour was detected.     

Spatial variation and commercial fishing of New Zealand abalone (Haliotis iris and H. australis)

The New Zealand abalone fishery produces about 1200 t annually, mostly from southern New Zealand. The fishery, based on Haliotis iris, is managed over broad management areas within which fishing intensity is spatially dispersed. The size composition of the commercial catch depends on location within a management area but is similar for divers fishing individual populations of H. iris and reflects the size composition of natural populations. For most populations, length‐frequency distributions of abalone were normally distributed: the mean shell length of H. iris was found to vary within populations over small spatial scales (100s m). The relative abundance of juvenile H. iris was low in relation to adults suggesting, at least for exposed populations, that rates of recruitment to populations of H. iris may be low. The relative abundance and mean shell length of juveniles and adults of H. australis was much less than that of H. iris. The scarcity of H. australis and the lack of separate catch quotas for the two species are factors which explain the low to zero catch of H. australis. The spatial variation in the size composition of H. iris suggests that management would be more appropriate over spatial scales which reflect local populations rather than the large spatial areas which are used to manage the New Zealand abalone fishery.     

Small‐scale spatial variation in growth,size at maturity,and yield‐ and egg‐per‐recruit relations in the New Zealand abalone Haliotis iris

Tag‐recapture studies revealed differences in the growth rate of Haliotis iris between headlands and bays separated by as little as 200 m. Individuals off headlands had a significantly higher incremental growth and reached a higher maximum size than those in bays. These results were consistent with observations of the size composition of H. iris which showed that few individuals of harvestable size (> 125 mm shell length) were found in bays. Differences in the growth rate of H. iris may account for the apparent differences in the size at onset of maturity: individuals off headlands, and from a fast‐growing population off Wellington, reached reproductive maturity at a smaller size compared with those in bays. Yield‐per‐recruit modelling showed greater yields from headlands than bays, but egg‐per‐recruit modelling revealed more egg production was conserved in bays than off headlands. Yields could be increased from bays by decreasing the minimum size to 110 mm. Egg‐ and yield‐per‐recruit models were sensitive to the natural mortality rate (M = 0.03, 0.05 and 0.10 compared). The results show that parameters important in the management of commercial fisheries for abalone can vary over small distances: such variation should be incorporated in management strategies for abalone fisheries.     

Population dynamics and fishery management of the paua,Haliotis iris

A population model is developed and used in conjunction with the results of a study of an unexploited population of paua (Haliotis iris Martyn) to examine the historical pattern of recruitment and yield per recruit. As H. iris cannot yet be aged, the population model uses size rather than age classes, but is structurally similar to the Leslie matrix model. Simulations suggest that the observed population size structure resulted from a short (about 5 year) period of high recruitment, preceded and followed by longer periods of low recruitment. Yield per recruit analysis shows that the present minimum legal size for the fishery (127 mm) provides close to the maximum yield per recruit for most stocks, although yield per recruit could be increased in some areas by a reduction in minimum legal size.     

Larval development of Boccardia knoxi,a shell‐infesting spionid polychaete

Larvae of Boccardia knoxi (Rainer) were reared in the laboratory after dissection from brood capsules extracted from the outer shell and perio‐stracum of Cookia sulcata and Haliotis iris collected from Tasman Bay, New Zealand. All the eggs within each brood capsule developed into embryos. The dissected larvae had provisional setae and fed on phytoplankton. Larval development is described through to metamorphosis.     

Thermal constraints on glycolytic metabolism in the New Zealand abalone,Haliotis iris: the role of tauropine dehydrogenase

Black‐foot abalone, Haliotis iris, were sampled from two populations in warm northern waters, and from two in colder southern waters. Abalone muscle is characterised by high activity of the glycolytic pyruvate reductase enzyme, tauropine dehydrogenase (TDH). Adductor muscle TDH was profiled for thermostability and activity to test the hypothesis that the enzyme may show adaptation in titre or kinetic characteristics reflecting thermal habitat. Temperature dependency of the apparent Michaelis‐Menten constant of TDH for pyruvate (_appKm_pyr) suggested eurythermal enzyme behaviour below 20°C, and compromised function at the higher temperatures of northern populations occurring in the summer months. Thermostability profiles and enzyme activities suggest TDH expression does not differ significantly among populations (P > 0.05), indicating that this locus shows no compensation for temperature. The optimal temperature for efficient TDH function, estimated from V_max./_appKm_pyr, is close to 20°C. The possible thermal constraints on glycolytic metabolism in H. iris are discussed.     

Hydrolytic enzymes of the paua Haliotis iris,a marine gastropod (note).

Extracts of the viscera of Haliotis iris (Martyn, 1784) were shown to hydrolyse 2‐hydroxy‐5‐nitrophenyl sulphate at pH 5.5, and the p‐nitrophenyl derivatives of α‐ and β‐D‐galactose, α‐ and β‐D‐mannose, α‐L‐lucose, β‐D‐glucuronic acid, β‐N‐acetyl glucosamine and phosphate at pH 4.0 and 5.5: p‐nitrophenyl‐β‐L‐fucose was not hydrolysed.     

Complete nuclear ribosomal DNA sequence analyses of the black-footed abalone Haliotis iris

The black-footed abalone Haliotis iris is an economically important shellfish species in New Zealand. We successfully amplified, sequenced and analysed the complete nuclear ribosomal DNA (nrDNA) of H. iris. The length of the nrDNA was determined to be around 9.6?kb and included, in order, small subunit ribosomal RNA (nrSSU, 1858bp), internal transcribed spacer (ITS, 749?bp), large subunit ribosomal RNA (nrLSU, 3412bp) and an intergenic spacer (IGS, 3560–3662?bp). The nrLSU genes were identical in two individuals, whereas the nrSSU and ITS regions existed at three and four base differences, respectively. The IGS was more variable than the other nrDNA regions. A phylogenetic tree was constructed based on the ITS sequence datasets, which revealed that Haliotidae has two major subclades, mainly distributed in the North Pacific, Europe and Australia. The complete nrDNA sequence will be useful for the classification, phylogeny and breeding of this shellfish.     

Use of probiotic bacteria to improve growth and survivability of farmed New Zealand abalone (Haliotis iris)

The effects of two probiotic feeds containing two and three bacterial isolates were evaluated on the growth performance of New Zealand abalone (Haliotis iris). Probiotic bacteria were isolated from the guts of healthy adult abalone. The isolates were screened qualitatively and quantitatively according to their ability to hydrolyse nutrients (i.e. proteins, starch and alginate), produce acid and resist bile salts. Based on the screening results, we developed a multi-strain conglomerate of 2- and 3- probiotic bacterial strains that were supplemented into a commercial abalone feed to use in our experiments. The 2-probiotic conglomerate consisted of Exiguobacterium JHEb1 and Vibrio JH1, and the 3-probiotic conglomerate consisted of Exiguobacterium JHEb1, Vibrio JH1 and Enterococcus JHLDc. The probiotic feeding trial involved abalone juveniles (20–30 mm in maximum shell length). Both probiotic feeds significantly improved abalone growth compared to that of the unsupplemented feed. The 3-probiotic supplemented feed produced a significant shell length increase of 20.9%, a wet weight gain of 19.8% and a five-fold reduction in mortality compared to the controls. The 2-probiotic supplemented feed resulted in significant increases in shell length (15.4%) and reduced mortality (five-fold), but not in weight gain, compared to controls.     

Shell use by sympatric hermit crab species in a seasonally open coastal lagoon in Northeastern Brazil

There are gaps in what is known about the patterns of gastropod shell use by hermit crabs in Brazilian lagoon areas, especially in Northeastern Brazil. However, this is important because the understanding of selection patterns provides information on life history and eco‐evolutionary conceptions of paguroids. The present study investigated the use of gastropod shells occupied by Pagurus criniticornis and Clibanarius sclopetarius in a coastal lagoon seasonally connected to an estuary and to the sea, correlating eco‐evolutionary aspects and hydrodynamic characters. The study was carried out between February 2013 and January 2014. Hermit crabs and their shells were identified and measured (hermit crabs’ cephalothorax shield length and width, major propodus length and height, weight, shell total length and width, shell aperture length and width). Partial least squares regression was used to analyse the morphometric data. Additionally, a multinomial proportions test was performed to infer patterns (inter‐/intra‐specific) of shells’ occupation. Hermit crab species occupied a total of 13 types of shells, predominantly those of Neritina virginea (67.83%). The shell weight was the most important determinant of shell occupancy in the morphometric model (variable importance in projection >1). The proportions of N. virginea shells used were similar in both species of hermit crabs, except between the sexes of P. criniticornis. Presumably, the high utilization rate of N. virginea shells is related to its abundance and dispersal, and to the shells’ suitability for hermit crabs, which is reflected by the morphometric model, as well as by the hydrodynamics of the lagoon‐estuarine environment. The relative occupation of different types of shells for each species of hermit crabs studied appears to be associated with regulation by inter‐/intra‐specific competition, which fosters the co‐occurrence of those populations. These results endorse coastal lagoons as a refuge and recruitment area for aquatic fauna. In addition, it highlights a challenge in the management and conservation of paguroid species whose population dynamics depend on the resources coming from the Gastropoda community.     

线粒体COI、COII和CYTB基因在鲍属物种鉴定中的适用性分析

为寻找最适于进行鲍属物种鉴定的线粒体基因, 测定了中国及日本沿海5 个皱纹盘鲍（Haliotisdiscus hannai）群体共16 个个体的线粒体基因COI、COII 以及CYTB 的完整序列, 并结合杂色鲍（H.diversicolor）、疣鲍（H. tuberculata）和黑唇鲍（H. rubra）的线粒体基...     

Notes on laboratory rearing of juvenile spiny lobsters,jasus edwardsii (hutton) (crustacea: Decapoda: Palinuridae)

Post‐puerulus specimens of Jasus edwardsii (Hutton) have been successfully reared in the laboratory from the puerulus stage for periods of up to 12 months. The spiny lobsters were reared in concrete‐asbestos tanks measuring 2.4m × 37cm × 23cm. The tanks were supplied with a continuous flow of sea water and provided with constant aeration. Empty shells of paua (Haliotis iris Martyn) and rocks from the intertidal zone provided cover within the tanks.

Fresh mussel (Mytilus sp.) was preferred to all other foods tried in feeding experiments. The animals were fed every second day on opened mussels, and occasionally on fresh fish. The juveniles “grazed” actively on the calcareous algae (Corallina officinalis L.) present on the rocks.

The animals were extremely sensitive to pollution. To reduce pollution risks all sediments were removed from each tank, as the interstices between them were found to harbour uneaten food particles. Any uneaten foods were siphoned out every second day and each tank was thoroughly cleaned every six to eight weeks.

From a total of over 3,300 animals collected since November 1965, over 800 are presently being reared in the laboratory and various aspects of their ecology studied. The first step in raising larger adult sizes from juvenile stages in the laboratory is clearly possible.     

Migrating eels in a Canterbury river,New Zealand

A fish trap in the upper reaches of the South Branch stream, Canterbury, New Zealand, caught eels from December 1957 to October 1964. The downstream migrations of immature and adult eels of both New Zealand freshwater species (short‐finned Anguilla australis and long‐finned A. dieffenbachii) were recorded. These migrations showed a seasonal and a lunar periodicity, and the larger runs were also influenced by rainfall, water volume, or the passage of a depression. Seasonal peaks were marked for mature eels of both species, and for immature A. australis, but not for immature A. dieffenbachii.     

Patterns in abundance,population structure and biology of knife prawn Haliporoides triarthrus on deep-water trawl grounds off eastern South Africa

The deep-water trawl fishery along the KwaZulu-Natal coast of South Africa targets several crustacean species, with the knife (or pink) prawn Haliporoides triarthrus contributing most of the catch. Logbook data of fishing effort and catch between 1988 and 2010 were used to assess the distribution and abundance of H. triarthrus on fishing grounds. Generalised linear models were used to quantify the effects of year, month and depth on catch rates. Standardised trends indicated a general decline in abundance between 1990 and 1998, followed by an increase between 2001 and 2008. Catch rates peaked in March, and they were highest between 200 and 499 m depth. Biological samples collected during commercial fishing were used to assess size and sex composition, growth rates and reproductive activity of H. triarthrus. Females became larger than males and mean carapace length (CL) varied by month. The youngest female cohort appeared in November (modal CL of 25 mm), and dissipated after two years (39 mm). Sex ratios were equal for all data combined, but fluctuated by month and CL. Few reproductively active females were recorded. Length-based methods and the standard von Bertalanffy growth function were used to estimate growth parameters (L_∞ and K) of females (40.6 mm CL and 1.06 y^–1) and males (35.2 mm and 1.27 y^–1) respectively. Our findings were compared with information on H. triarthrus from Mozambican waters.     

Size‐Frequency Distributions of Miocene Micromorphic Brachiopods: Interpretation Tool for Population Dynamics

Abstract. The population dynamics of the fossil micromorphic brachiopods from shallow‐water Miocene deposits (calcareous clays to hard bottom of reef cavities) of the Roztocze Hills, south‐eastern Poland were studied by means of size‐frequency distributions. The following four species, which all also occur in the Recent Mediterranean, were used for the study: Megathiris detruncata (Gmelin), Argyrotheca cuneata (Risso), A. cordata (Risso) and Megerlia truncata (Linnaeus).
The size‐frequency distributions for 28 assemblages studied here vary widely, even within a single species, from right‐skewed, through bell‐shaped to polymodal; no left‐skewed distribution was noted.
The size‐frequency distributions with a large peak in the smaller size classes represent mostly assemblages collected from marly deposits. Those assemblages may be interpreted as inhabiting soft bottoms where small brachiopods are more vulnerable to burial by sediment and/or clogging effects on the lophophore apparatus.
The assemblages collected from the reef cavities produced bell‐shaped size‐frequency distributions or distributions with a relatively high percent of larger individuals. This is because the protected hard bottom cryptic habitats are characterised by lower juvenile mortality and enable the brachiopods to reach a larger size.
These results suggest that environmental factors play a crucial role in shaping brachiopod population structures, and that empty shells can be used to study population dynamics as well in Recent environments.     

Downstream migration of Geotria australis juveniles in the lower Waikato River (note)

Juvenile migrants of Geotria australis were caught from July to early August 1986 in plankton nets set in the lower Waikato River. Migration occurred only at night and mainly mid‐river at the surface. The mean lengths and weights (± 95%c.i.) were 107.75 ± 3.98 mm and 0.94 ± 0.08 g respectively.     

Parasitic barnacles (Cirripedia: Rhizocephala) from New Zealand off‐shore waters

Nine genera and species of rhizocephalans were recorded from the off‐shore waters around New Zealand. Mitochondrial and nuclear gene sequences were used to examine base differences between the European and New Zealand species of Parthenopea. Serial sections to study the internal structures of the reproductive organs were made for the genera Thylacoplethus and Thompsonia. Two species, Parthenopea australis n. sp. and Thylacoplethus novaezealandiae n. sp. are new to science and described in detail. Parthenopea australis n. sp. is the first rhizocephalan species recorded from the vicinity of active cold seeps. Three rhizocephalans could not be identified as they were parasitised by hyperparasitic cryptoniscine isopods. The decapodhost species comprised the taxa Paguridae, Lithodidae, Galatheidae, Chirostylidae, and Callianassidae.     

皱纹盘鲍血细胞吞噬发光的研究

于１９９８年７月从大连碧龙海珍品有限公司购得人工养殖的皱纹盘鲍,运用化学发光法研究在体外条件下利用６种活性氧清除剂ＳＯＤ（超氧化物歧化酶）、ＣＡＴ（过氧化氢酶）、苯甲酸钢和ＤＭＦ（二甲基呋喃）、ＮＢＴ（硝基四唑蓝）及金属螯合济ＥＤＴＡ（乙二胺四乙酸）等试齐对皱纹盘鲍血细胸吞噬活动中化学发光的产生和影响。结果表明,活性氧清除剂对皱纹盘鲍血细胞的吞噬发光都有掏作用,说明皱纹盘鲍血细胞在吞噬活动中能够释     

Growth of the European abalone (Haliotis tuberculata L.) in situ: Seasonality and ageing using stable oxygen isotopes

The ormer, Haliotis tuberculata is the only European abalone species commercially exploited. The determination of growth and age in the wild is an important tool for fisheries and aquaculture management. However, the ageing technique used in the past in the field is unreliable. The stable oxygen isotope composition (¹⁸O/¹⁶O) of the shell depends on the temperature and oxygen isotope composition of the ambient sea water. The stable oxygen isotope technique, developed to study paleoclimatological changes in shellfish, was applied to three H. tuberculata specimens collected in north-west Brittany. For the specimens collected, the oxygen isotope ratios of the shell reflected the seasonal cycle in the temperature. From winter-to-winter cycles, estimates of the age and the annual growth increment, ranging from 13 to 55 mm per year were obtained. This study shows that stable oxygen isotopes can be a reliable tool for ageing and growth studies of this abalone species in the wild, and for validating other estimates.