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1.
Abstract

Bacterial numbers and production were measured in the upper water column in the winter and spring of 1993 in five water masses surrounding the South Island of New Zealand. Average bacterial numbers and production were found to be higher in spring (8.5 × 105 cells ml?1 and 0.20 mg m3 h?1, respectively) than winter (5.5 × 105 cells ml?1 and 0.05 mg C m3 h?1 respectively). Bacterial production was strongly correlated with chlorophyll a and primary production (P < 0.001) in spring but not in winter. Spring bacterial production and at 10 m depth averaged across 28 stations was 23% of primary production, and with a growth efficency of 40%, may have consumed up to 57% of primary production. Bacterial biomass was greater than phytoplankton biomass for 75% of the 10 m depth comparisons during winter sampling and 44% during the spring sampling. The bacterial biomass was found to represent 24.6–33.5% of the nitrogen in particulate organic matter (<200 μm) supporting the concept that in New Zealand oceanic water masses bacteria are of significant biogeochemical importance.  相似文献   

2.
Distribution of shipworms (Bivalvia: Teredinidae) in the New Zealand region   总被引:1,自引:1,他引:0  
Bankia neztalia was found in temperate waters around New Zealand, mainly south of New Plymouth and Tauranga. Bankia australis was found in warm‐temperate waters north of Nelson; it requires water temperatures above 19–20°c for successful breeding and is euryhaline. Lyrodus pedicellatus also occurred in warm‐temperate waters north of Nelson and had a lower water temperature limit for survival of about 10 °c. Lyrodus medilobatus occurred in warm‐temperate waters on the north‐east coast of the North Island north of Tauranga. Nototeredo edax is uncommon and occurred over the same range as B. australis.

The presence of shipworms in wood collected from depths of greater than 50 m around New Zealand is reported. Teredora princesae is recorded from driftwood around New Zealand.  相似文献   

3.
ABSTRACT

National-scale analyses of land cover effects on water quality can aid in directing environmental policy. We compiled a coastal water quality database for New Zealand comprising 320 estuarine and coastal sites with records between 2013 and 2018. Previous literature had shown strong effects of agricultural and urban land cover on the quality of New Zealand’s rivers, so we examined their effects on estuaries, while controlling for marine dilution and freshwater flushing. Sites with greater freshwater influence had higher nutrient and faecal indicator bacteria concentrations, and turbidity, indicating that open coast and estuarine water quality is reduced predominantly via flows from the land. Nitrate, ammonium, total and dissolved reactive phosphorus, and water column chlorophyll-a concentrations were greater in estuaries with higher urban land cover and total phosphorus concentrations were greater with higher agricultural land cover. There was a marginally significant increase in turbidity as agricultural land cover increased. This is the first national-scale compilation and analysis of New Zealand coastal water quality data, and the first national analysis of land cover effects on water quality in New Zealand estuaries.  相似文献   

4.
Abstract

Substrate and infauna samples were taken at four tidal levels (mean high water springs, high mid beach, low mid beach, and mean low water neaps) with a 0.0625 m2 quadrat at 14 North Island beaches in New Zealand. The distributions of Peracarida (Crustacea) were correlated with sediment type, tidal height, and degree of exposure; sampling began in March 1972 and was completed in November 1973.

Substrate samples were sieved and median diameter of the particles ranged from very coarse sand of — 0.60? to very fine sand of + 3.259?. Substrates were variously sorted: ? quartile deviation ranged from 0.14? to 0.66?, skewness from 0.08? to + 0.07?.

Peracarid fauna was moderately abundant; the maximum value was 720 animals per square metre on a fully exposed beach. Highest average abundance (303 per square metre) for the 14 beaches was recorded from the mean low water neap station. Amphipoda was the dominant group (54% of all Peracarida recorded), followed by Isopoda (33%) and Cumacea (13%). Frequency of occurrence at the 56 stations was headed by Amphipoda (64%), followed by Isopoda (46%), and Cumacea (20%).

The results are compared with data from Stewart Island beaches, and the biogeographical distributions of recorded Peracarida are discussed. An unexpectedly high degree of endemism exists for a warm‐temperate region, caused by the isolation of New Zealand, which has no direct shallow water contact with tropical or cold temperate regions.  相似文献   

5.
ABSTRACT

The grounding of the MV Rena in 2011 necessitated urgent entry of salvage vessels into New Zealand. Two, a cargo barge and tug, had been idle in Australia before mobilisation and had well-developed biofouling assemblages that included non-indigenous species new to New Zealand. Surveillance for the species was initiated in Tauranga harbour, Astrolabe Reef and Mōtītī Island, where the vessels had operated. Response personnel were trained to recognise and report the organisms and active surveys were implemented, including reinspection of the vessels after treatment of the biofouling, dive and shoreline searches, and trapping. Although none of the risk species was detected, the biosecurity risk from the vessels changed during the response, from initially acting as a vector for species new to New Zealand to later transporting non-indigenous species from coastal ports to the arena of operations. The study highlights a need for better integration of biosecurity risk management into forward planning for maritime incidents.  相似文献   

6.
ABSTRACT

The grounding of the MV Rena has highlighted the lack of information concerning the effects of oil-related compounds on New Zealand marine life. Yellowtail kingfish (YTK), Seriola lalandi, embryos were exposed in static incubations to the water-accommodated fraction (WAF) of Rena heavy fuel oil as well as a similar preparation treated with the commercial dispersant Corexit 9500. Mortality in WAF treatments generally increased in association with total polycyclic aromatic hydrocarbon (tPAH) concentration over a 24-h period. Physical abnormalities were observed in some of the larvae exposed to WAF for 48 h. There was no survival in dispersed oil treatments after 24 h of exposure. These treatments had greater tPAH concentrations (2–53?µgL?1) than equivalent WAF dilutions (0.2–1.5?µgL?1?tPAH). Indications are that significant morbidity is induced in YTK at ecologically relevant tPAH concentrations. This highlights the need for further research into oil and dispersant toxicity in New Zealand marine species.  相似文献   

7.
ABSTRACT

The sinking of the MV Rena on Astrolabe Reef (Otaiti) in the Bay of Plenty, New Zealand, resulted in the release of oil and ship debris, including dangerous goods carried as cargo. Two key questions of concern to the public and environmental managers were posed immediately: what was the impact of the Rena oil spill and how long would it take for the marine environment to recover? The research that began immediately after the ship grounded provided answers, as documented in this special issue.  相似文献   

8.
ABSTRACT

In contrast to previous reports that leopard seals (Hydrurga leptonyx) are rare vagrants to New Zealand, we show that this species is a regular member of the marine fauna of this region. We present a first analysis from the New Zealand Leopard Seal Database – an extensive collation of 2,711 records of leopard seals within New Zealand between 1200 and 2018. Of these records, 51.2% (n?=?1,408) were photographic. Leopard seal sightings have increased over time and been reported in all seasons and regions of New Zealand. Sightings are predominantly of adult individuals of good or excellent body condition, which differs to previous hypotheses suggesting that leopard seals visiting New Zealand shores are primarily juvenile animals in poor health condition. A total of 176 unique individuals have been identified in the New Zealand Leopard Seal Catalogue between 2014 and 2018 and preliminary results indicate that numbers per annum have continued to increase over time. Three leopard seal births and a number of juvenile animals (34% of the NZ records) have been documented. Considering the information presented here and the current definitions in the New Zealand Threat Classification System, the threat status of leopard seals within New Zealand waters should be reclassified from Vagrant to Resident.  相似文献   

9.
The poeciliid fish, Phalloceros caudimaculatus (commonly referred to as the “caudo"), is recorded from the wild for the first time, occurring in stock‐water troughs on a farm near Kamo in Northland, New Zealand. The populations in the stock troughs reputedly came from a nearby stream c. 10 years ago, although a preliminary search has failed to reveal them to be there now. Presence of an additional exotic fish in New Zealand fresh waters is a matter for concern, and requires management. To facilitate recognition off. caudimaculatus, and its distinction from other poeciliids present here, a diagnosis is provided to enable identification, together with notes on natural history, and a key for the identification of the five species of Poeciliidae now known from natural waters in New Zealand.  相似文献   

10.
A colonial ascidian was first reported by marine farmers in Houhora Harbour, Northland, New Zealand in early 2005 and subsequently found on oyster racks in Parengarenga Harbour and the Bay of Islands. The Northland ascidian was identified with a combination of morphological characters and DNA cytochrome c oxidase I (COI) sequence data, as Eudistoma elongatum, a species native to Australia, where it is found from northern New South Wales to Northern Queensland, and distinguished from Eudistoma circumvallatum, the only reported species in this genus from New Zealand. Ascidian larvae are weak dispersers and long distance dispersal of E. elongatum is likely to be enhanced by vectors such as oyster barges and/or movement of cultured oysters. In its native range, E. elongatum is restricted to areas with a minimum winter sea temperature of 16°C. Assuming similar biological limitations apply in New Zealand, the spread of E. elongatum might be restricted to northern New Zealand (north of latitude 37°S).  相似文献   

11.
ABSTRACT

Water is an important component of many recreational opportunities and New Zealand invests significant resources in recreational water quality (RWQ) monitoring to assess risks to public health. However, monitoring primarily focuses on microbiological hazards and RWQ is considerably broader than this. The goal of this study was to take a comprehensive approach to evaluating RWQ while exploring the potential for greater public involvement in monitoring. A popular river swimming site was co-monitored weekly by volunteers and a council field officer. The attributes monitored–water temperature, visual clarity, benthic cyanobacteria and filamentous periphyton cover, E. coli and rubbish–were identified from a volunteer workshop. There was good concordance between volunteer and council data suggesting that volunteer measurements can be considered reliable. This highlights the potential for volunteers, with professional support, including training and quality assurance, to extend council RWQ surveillance to additional monitoring sites while improving public engagement on water management.  相似文献   

12.
Xenophyophores are a group of giant, but extremely fragile, rhizopod protozoans generally found at lower bathyal or abyssal depths. Recent dredge samples and photographs suggest that there is a largely endemic fauna of xenophyophores with anastomosing branches living at upper bathyal depths around New Zealand. Their distribution may be related to the layer of Antarctic Intermediate water that bathes the upper slope of the New Zealand Plateau.

Photographs of the seafloor at depths of 800–1300 m on the Lord Howe Rise show hemispherical masses, 5 cm across, of which the majority appear to be Syringammina tasmanensis Lewis, 1966 and at least one specimen may be Reticulammina lamellata Tendal, 1972. The photographs indicate that these species live on the seabed, not beneath it, that they are probably filter feeders and that they can reach a density of about one specimen per square metre.

A new species, Reticulammina maini, is described from the continental slope east of Auckland. A key to the New Zealand species of xenophyophore is presented.  相似文献   

13.
ABSTRACT

Determining the genetic structure and population dynamics of harvested species are key aspects of effective fisheries management. New Zealand scampi (Metanephrops challengeri) is a species of nethropid lobster that supports a commercial fishery on the continental shelf and slope around New Zealand. To determine the genetic structure and historical population demography of New Zealand scampi, we sequenced a 623 base-pair fragment of the mitochondrial gene cytochrome c oxidase subunit one (CO1) from 321 individuals across six widely separated sites off the coast of mainland New Zealand and the subantarctic Auckland Islands, representing much of the species’ distribution. The Auckland Islands population was found to be genetically distinct from all other sampled populations, potentially resulting from an absence of continuous suitable habitat between the central-eastern South Island and the Auckland Islands. An isolation-by-distance pattern of genetic structure was also detected. With the exception of the Mercury Islands, all sampled populations showed signs of recent population expansion, potentially linked to changes in habitat availability during the glacial-interglacial cycles of the Pleistocene. We recommend that the current NZ scampi management areas and harvesting rates for each remain unchanged.  相似文献   

14.
Abstract

The milk composition of New Zealand sea lion, Phocarctos hookeri, was determined using standard analytical methods, a MilkoScan? FT 120 and an accelerated solvent extractor (ASE) for fat concentration. The results for fat, protein and total solid concentrations between the different analytical methods were assessed using different measures of statistical fitness including coefficient of determination, concordance correlation coefficient, mean prediction error, and intraclass correlation coefficient. The repeatability and reliability of the results obtained with the calibrated MilkoScan? FT 120 were comparable with those obtained using standard methods, the Roese‐Gottlieb method for fat, Kjeldahl method for protein and gravimetric method for total solids. The MilkoScan? FT 120s are fast and cost‐effective and are widely used in dairy laboratories around the world, which should make them readily accessible to ecologists/biologists studying the milk composition of non‐domestic animals.  相似文献   

15.
ABSTRACT

The genus Xenostrobus consists of small, marine and estuarine mussels that all appear similar externally. One of its estuarine species, Xenostrobus securis, with a native range in New Zealand and Australia, has become invasive in the Northern Hemisphere. No genetic data are available to determine if X. securis populations from the two countries are conspecific. Additionally, marine Xenostrobus from New Zealand have often been regarded as a species, X. neozelanicus, distinct fromthe marine Australian species X. pulex. We combined new DNA sequences with published data to assess the taxonomic status of New Zealand Xenostrobus. The data comprised 658 aligned bases of mitochondrial cytochrome c oxidase subunit I (COI) gene and 331 bases of nuclear histone H3. There was no evidence that X. securis populations from Australia and New Zealand are specifically distinct. Northern Hemisphere specimens of X. securis belonged to Australian, not New Zealand, clades in phylogenetic analyses of COI data, suggesting the former country as their more likely original source. The results confirm that X. neozelanicus and X. pulex are distinct species and for nomenclatural completeness for this taxonomic decision a lectotype is designated for Mytilus ater Zelebor in Dunker and Zelebor, 1866 DunkerW, ZeleborJ. 1866. Bericht über die von der Novara-expedition mitgebrachten Mollusken. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wien. 16:909916. [Google Scholar] [?=?Modiolus neozelanicus Iredale, 1915 IredaleT. 1915. A commentary on Suter’s ‘Manual of New Zealand Mollusca’. Transactions of the New Zealand Institute. 47:417497. [Google Scholar]].  相似文献   

16.
Shells of commercially valued bivalves in New Zealand, Crassostrea gigas, Perna canaliculus and Pecten novaezelandiae, are damaged by blister-causing Polydora polychaete species known to be close in morphology to the widely recorded oyster pest Polydora websteri Hartman. Recent New Zealand occurrences are here confirmed to relate to two species, P. websteri, and a second similar species, Polydora haswelli Blake & Kudenov, a new record for New Zealand, previously known only from Australia; the two species are described and compared. The worms have limited distributions, with P. websteri confirmed only for Pacific oysters (C. gigas) in northern New Zealand, although prior reports indicate it may also occur on scallops and have reached the northern South Island. Polydora haswelli has been found only in northern New Zealand, occurring on subtidal mussels and scallops and native oysters (Perna canaliculus, Pecten novaezelandiae, Ostrea chilensis), as well as co-existing with intertidal P. websteri on Pacific oysters. The worms are not present in Foveaux Strait O. chilensis beds, a major source of past oyster exports to Australia. The history of mud-blister worm outbreaks in Australasia is examined. While trans-Tasman exports of live oysters from New Zealand were commonplace during the nineteenth century, there is no evidence that mud-blister worms were present in New Zealand then. The earliest reports only date from the early 1970s and only from northern New Zealand, whereas a century earlier in the 1870s at least one of these pest worms had become widespread along eastern Australian coasts.  相似文献   

17.
Abstract

Polychaetes were collected from eight sites across the Chatham Rise (New Zealand) in the region of the Subtropical Front from water depths of c. 2300 m to 350 m. A total of 169 putative species representing 36 families was identified. Spionidae, Paraonidae, Cirratulidae, Syllidae, and Orbiniidae accounted for 50% of all polychaete individuals. Multivariate analysis revealed that three sites at c. 350–453 m water depth on muddy sand (6–7% clay) shared similar faunal and environmental characteristics. Numerical dominants included Lumbrineris sp., P seudeurythoe minuta, Dipolydora cf. socialis, Aglaophamus verrilli, Prionospio lehlersi, Syllinae sp., Monticellina sp., and Cossura sp. Replicates from a single site at c. 750 m depth on the southern flank of the Rise produced a distinct assemblage dominated by Paradoneis, Naineris, Notomastus, Harmothoinae, Prionospio lehlersi, Levinsenia, Aricidea, Kebuita, Paraonella, and ?Leiochrus species. Replicates from greater depths north and south of the Rise presented a greater range of assemblage characteristics and environmental parameters including temperature, dissolved oxygen, median grain size, calcium carbonate (CaCO3), and total organic matter content. Twenty‐eight taxa were found exclusively below 750 m depths including species of Ampharetinae, Chloeia, Pseudeurythoe, Capitellidae, and Cirratulidae. There was a significant difference in faunal composition between northern and southern flanks of the Rise within depth classes and also between sites at the same depth classes. Faunal density and species diversity appeared highest from the crest to 750 m depth on the southern side. Low species diversity at the deepest sites may be confounded by reduced density.  相似文献   

18.
Twelve species of barnacles were identified from the fouling community on the parts of the ‘Maui’ oil platform that were submerged during its tow from Japan in 1975 and after its arrival in New Zealand. The stalked barnacles Lepas anatifera L. var. (a) Darwin, L. anserifera L., Conchoderma auritum (L.), and C. virgatum (Spengler) probably settled during the tow across the tropical Pacific, and have been recorded in New Zealand waters before from ships (the Lepas spp.) and vertebrates (the Conchoderma spp.). The acorn barnacles were small, and probably settled in Japanese waters; Balanus variegatus Darwin and B. amphitrite Darwin already occur in northern New Zealand waters. The other six species—B. improvisus Darwin, B. albicostatus Pilsbry, B. reticulatus Utinomi, Megabalanus volcano (Pilsbry), M. rosa (Pilsbry), and Tetraclita squamosa japonica Pilsbry—have not been recorded from New Zealand before.  相似文献   

19.
20.
The tonnacean genus Thalassocyon Barnard, 1960 contains only two species, T. bonus Barnard, 1960 from deep water off South Africa and T. mi Dell, 1967 from deep water off northern New Zealand. The genus is removed from the Cymatiidae and placed in the Ficidae on the basis of shell morphology, the reduced periostracum and the details of the radula.  相似文献   

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