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1.
The distribution and movements of sperm whales, Physeter catodon Linn., in the western South Pacific (latitudes 30–70° S, longitudes 150E‐150°W) are examined. An undetermined number of catches by nineteenth century American whaleships, 9,720 catches by pelagic fleets in 1961–70, and 427 sightings in 1967 are analysed and correlated with oceanographic data from Australian and New Zealand surveys.

The proportion of females decreases southwards, abruptly at about latitude 44° S in the Tasman Sea, and at about 46–47° S east of New Zealand. Virtually no females occur south of 50° S. The male population density also decreases southwards: the density between 50–70° S appears to be less than 25% of that between 30–50° S. Sperm whales also appear to be less abundant in the eastern part of the region away from the New Zealand plateau, but more data are required.

The pattern of distribution and its seasonal changes probably correlate with vertical temperature gradients of about 5°c in the upper 100 m of water, i.e., optimal conditions for squid schooling. Catch per unit effort in autumn is lower than in spring. A northward population shift in autumn is inferred, based on reduction of available food species and probable temperature tolerances of calves, most of which are born in February and March, towards the end of the southern summer. Some males overwinter in areas where suitable gradients persist, e.g., around the Chatham Islands.

Possibly the summer surface temperature maxima south of the South Island are low enough to inhibit the passage of breeding schools with calves from one side of the New Zealand archipelago to the other. Sperm whales do not pass through Cook Strait normally. Thus, unless considerable mixing of stocks occurs north of New Zealand in winter, there may be two “unit stocks”, one oscillating seasonally between the central Tasman Sea and the Fiji‐Tonga region, and another (probably smaller) between the east coast of the South Island and the region just north of the Chatham Islands.  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.
Eight species of Pycnogonida collected by University of Canterbury Expeditions and the New Zealand Oceanographic Institute are recorded from the Snares Islands, which lie at 48° 05’ S, 166° 20’ E, 60 miles SW of South Cape, Stewart Island. The following species are recorded: Pallenopsis obliqua (Thomson, 1884), Cheilopallene trappa n.sp., Ammothea magniceps Thomson, 1884, Achelia dohrni (Thomson, 1884), Tanystylum cavidorsum Stock, 1957, Ascorhynchus insularum n.sp., Austrodecus minutum n.sp. and Austrodecus enzoi n.sp.  相似文献   

4.
The spiny lobster Jasus edwardsii (Hutton) supports a thriving new fishery at the Chatham Islands, about 770 km east of New Zealand. Commercial fishing for J. edwardsii started in November 1965, and within 2 years the area became a major centre of New Zealand's large spiny lobster fishery, which earned >NZ$5,000,000 in 1967. Over 12 months (September 1966 to August 1967) landings at the Chatham Islands made up 39.8% of the total New Zealand spiny lobster catch of 16,600,0001b.

In the first year of fishing 2,177,923 lb of spiny lobsters were caught, and in the second 7,129,658lb—a 227% increase. Fishing effort also increased substantially: average number of boats fishing each month rose by 174% in the second year, and the total number of boat‐fishing days by 152%. Most specimens of J. edwardsii caught are large and mature, typical of a virgin stock.  相似文献   

5.
6.
Direct measurements of coastal currents around southern New Zealand   总被引:2,自引:2,他引:0  
Results are presented from direct measurements of subsurface currents at ten coastal positions around the southern half of New Zealand, and from geomagnetic electrokinetograph measurements of surface currents between these positions. Currents on the continental shelf were predominantly tidal. Strongest mean flows were found on the continental slope adjacent to areas where the continental shelf is narrowest. The flow on the west coast of the South Island was southwards south of 44° S, with a maximum mean speed at a depth of 100 m of 0.64 m.s‐1. On the east coast of the South Island the flow was generally towards the north, with a maximum speed at a depth of 100 m of 0.21 m.s‐1 near latitude 42° 30’ S.  相似文献   

7.
In January 1970, 309 pups of the New Zealand fur seal, Arctocephalus forsteri (Lesson, 1828), were tagged on Taumaka Island, one of the Open Bay Islands, Westland, New Zealand (43°52’ S, 168°53’ E). At about 6 weeks old, male pups have longer flippers and are longer and heavier than female pups.

A population estimate of seals on Taumaka Island is based on a count of pups of the year, to which data from related species of fur seals were applied (incidence of pregnancy and age at first pupping from Arctocephalus pusillus, immature mortality from Callorhinus ursinus), and on the assumptions that the sex ratio and sexual mortalities are equal. There were at that time 2,000–3,000 seals, including pups, on the island.  相似文献   

8.
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   

9.
Since 1967, New Zealand fur seals (Arctocephalus forsteri) have been seen in winter on Three Kings Islands (34°10'S, 172°08'E) in increasing numbers, up to 80 in 1969. Approximately 130 were also seen on Motupia Island (34°37'S, 172°48'E) in 1969.  相似文献   

10.
Pycnogonida collected at the Antipodes Islands (49° 45’ S, 178° 45’ E) by the University of Canterbury Antipodes Islands Expedition 1969 and during New Zealand Oceanographic Institute cruises are reported on here, and constitute all material known for this group of animals from these islands. To date eight species are known; two are endemic, (Pallenopsis antipoda n.sp. and Ammothea antipodensis n.sp.); two constitute a circum‐polar element (Tanystylum cayi‐dorsum Stock and Austrodecus breviceps Gordon); the remaining four species are known also from New Zealand mainland waters (Pallenopsis obliqua (Thomson), P. kupei n.sp., Achelia dohrni (Thomson) and Ammothea magniceps Thomson), as is T. cavidorsum. An attempt is made to indicate the range of variation in Achelia dohrni, and Pallenopsis mauii Clark, 1958 is redescribed although not a part of the Antipodes Islands fauna.  相似文献   

11.
Lepidocybium flavobrunneum (Smith, 1849) is widespread in warmer oceanic waters and has recently been recorded in the catches of tuna longline vessels in the New Zealand region. Twenty‐five specimens were caught at 31°46′‐32°03′S, 170°49′‐171°11′ E on 23–27 June 1979, thus extending the known range of the species to northern New Zealand.  相似文献   

12.
Abstract

New Zealand sea lions, Phocarctos hookeri (Gray, 1844), on Main Island of the Snares Islands (48° S) are restricted to the eastern coastal region between Molly Bay and Punui Bay. In the 1970–71 summer, a maximum of 47 sea lions (36 ?, 11 ?) was counted in one day, 5 January 1971.

A female and pup were seen several times in January and February 1969, and a second mother‐pup pair in January 1971. These sightings, with a similar record in 1907, show that small numbers of sea lions may breed on the Snares Islands, north of the main breeding area at the Auckland Islands (51° S).  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.
Hoki (Macruronus novaezelandiae Hector) year class strength (YCS) varies substantially from year to year. We examined associations between YCS and climate variables including the Southern Oscillation Index (SOI), satellite sea surface temperatures (SSTs), synoptic weather patterns, wind speeds, and the depth of the west coast, South Island, New Zealand, mixed layer. We evaluated the predictions of a model developed 2 years ago to predict YCS of the western and eastern New Zealand hoki stocks from similar climate variables. New predictive models were developed using updated data. Strong year classes of the western hoki stock were associated with cooler SSTs, a negative SOI, and westerly or south‐westerly flow along the west coast of the South Island. We accordingly predict a moderately strong 1997 year class and weak 1998 and 1999 year classes for the western stock of hoki. The current model cannot predict eastern stock year class strengths with confidence.  相似文献   

15.
Polychaete assemblages are described from replicate box‐core samples collected in summer 1983 at 18 stations on the continental shelf and upper slope (28–943 m) off the west coast of the South Island, New Zealand, south‐eastern Tasman Sea (c. 41–43°S, 169–172°E). Three main station groupings were identified by multivariate analysis: (1) inner shelf sandy stations characterised by Prionospio australiensis, Aricidea (Acesta) sp., Magelona cf. dakini, Paraprionospio aff. pinnata, Aglaophamus sp., Heteromastus filiformis, and Magelona sp.; (2) middle to outer shelf muddy stations characterised by Levinsenia cf. gracilis, Prionospio australiensis, Paraprionospio coora, Aglaophamus verrilli, and Auchenoplax mesos; and (3) upper slope sandy mud or mud stations characterised by Prionospio ehlersi. A combination of water depth and sediment clay content provided the best correlation with the biotic pattern. Spionidae was the most abundant family (49% of polychaete individuals), which may reflect the scope for opportunistic species in a shelf environment characterised by a high input of terrigenous sediment and episodic upwelling.  相似文献   

16.
Three new species of calanoid copepod in the family Aetideidae are described, two in Aetideopsis Sars, 1903 and the third in Bradyidius Giesbrecht, 1897. One Aetideopsis species is from off South West Africa (south‐east Atlantic), the remaining species are from the east coast of New Zealand (south‐west Pacific). The genus Pseudaetideus Wolfenden, 1904 is merged with Aetideopsis.  相似文献   

17.
Settlement of the puerulus stage of Jasus edwardsii (Decapoda: Palinuridae) near the shore takes place over a wide depth range. It occurs intertidally, and, as determined by crevice collectors, also takes place down to depths of at least 50 m. At sites along the east coast of the North Island of New Zealand, depth of greatest settlement found on collectors varied with locality and time, but was within the upper 11.5 m. Surface‐buoyed collectors caught fewer animals than did collectors at greater depths. Settlement levels generally increased with depth to about 10–12 m, then decreased with increasing depth and distance from shore. The ability of/, edwardsii to settle over a wide depth range may improve its chances of recruitment. A device (closing crevice collector) for measuring puerulus settlement of J. edwardsii at depth is described.  相似文献   

18.
Records of four species of Delphinidae, Delphinus delphis, Lissodelphis peroni, Lagenorhynchus obscurus, and Lagenorhynchus cruciger in waters to the east and south‐east of New Zealand are discussed in relation to surface temperatures.

In this region D. delphis appears to be largely confined north of the Subtropical Convergence and a minimum surface temperature of about 14°c, and near New Zealand from Hawke Bay southward in the warm water of the East Cape Current; L. peroni to the Subtropical Convergence and the subantarctic water to the south of it, between surface temperatures of 9°c and 16°c; L. obscurus to the immediate vicinity of the Subtropical Convergence and surface temperatures in summer of about 14° to 15°c, and L. cruciger across the Antarctic Convergence region, in a surface temperature range of 2° to 9°c.  相似文献   

19.
Nursery grounds of the tarakihi Cheilodactylus macropterus (Bloch & Schneider) were discovered in 1963–72 mainly off the south‐western coast of the North Island, in Tasman Bay, along the entire eastern coast of the South Island, and around the Chatham Islands. They occurred at depths of 20–100 m, and mostly between 10 km and 30 km from shore. The tarakihi nurseries had a dense and varied invertebrate bemthic epifauna dominated by sponges and small corals. Few signs of nurseries were found in. other New Zealand waters, in spite of the existence of major spawning grounds there. It is not known with which spawning grounds the various nursery grounds are linked.

The Tasman Bay nursery ground is 18–33 km wide and about 75 km long, with a surface area of about 2000 km2. There is a rich demersal fish fauna (37 species were recorded) dominated by tarakihi, red gurnard Chelidonichthys kumu (Lesson & Garnot), snapper Chrysophrys auratus (Bloch & Schneider), and leathei'iacket Novodon convexirostris (Guenther). The young tarakihi occur at depths of 20–45 m and concentrate during winter in the warmer deeper water. They first appear in trawl catches in summer, towards the end of their first year (assumed birthdate is 1 March), and stay on the nursery until the age of 3 y. They occur in the deeper water off the nursery during their fourth and fifth year and depart during their sixth year, possibly for the spawning grounds off the west coast of the South Island. The mean lengths at the ages of 15, 27, and 39 months were 12.6, 18.0, and 24.0 cm respectively in 1970. There was some variation in growth rate within the nursery ground, but the age groups could nevertheless be recognised easily from, length frequency modes. Monthly modal lengths showed that growth slows down in winter. Evidence for fluctuations in year class strength was found; year classes 1966 and 1969 were weak and year class 1968 was strong.

The vulnerability of tarakihi less than 4y old to commercial New Zealand trawl gear is low, and the local fishing fleets do no serious damage to the habitat on the nursery grounds. However, a large part of the tarakihi nursery grounds off the east coast of the South Island lies outside the territorial fishing zone. Intensive fishing on these grounds by large foreign vessels using heavy trawl gear could have an adverse effect on the habitat of the young tarakihi in this region.  相似文献   

20.
Absorbance at 360 nm and dissolved organic carbon (DOC) concentration were measured on 47 filtered water samples collected from streams and rivers of the west coast of South Island, New Zealand. The regression equation (DOC (g m‐3) = 59.6 Abs1 cm + 1.9) calculated from the data, reliably predicted DOC concentration within the range 1.6–43.2 gm‐3. This relationship is similar to that found fsr some Venezuelan and south‐eastern United Stales waters indicating that it may have widespread utility for estimating DOC concentrations in soft waters where DOC is dominated by humic substances  相似文献   

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