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131.
The diets of eight demersal fish species from the upper continental slope (c. 24CM‐50 m) were determined from samples taken during late January and early February 2004, off the Wairarapa coast, North Island, New Zealand. Diets were from a combination of benthopelagic and benthic sources, with most species exhibiting ontogenetic shifts in diet, in that larger‐bodied food (fish and/or natant decapod prawns) was more important in the diets of larger fish. Javelinfish (Lepidorhynchus denticulatus), silver roughy (Hoplostethus mediterraneus), and capro dory (Capromimus abbreviatus) had predominantly benthopelagic diets, whereas the diets of sea perch (Helicolenus percoides), Bollons’ rattail (Caelorinchus bollonsi), two‐banded rattail (C. biclinozonalis), and silverside (Argentina elongata) were predominantly benthic, with the crab Carcinoplax victoriensis an important food item. The diet of Oliver's rattail (C. oliverianus) was a mix of benthopelagic and benthic organisms. Generally, levels of dietary overlap between the eight species were low. Overall, the diets of these fish probably reflect regional and seasonal levels of food availability. Notes on food observed in the stomachs of a further 18 species, for which there were fewer than 10 stomach samples per species are also provided.  相似文献   
132.
Fishing activities have the potential to alter the behaviour of cetaceans and pose a threat through bycatch. We present observations concerning the influence of inshore trawling on group size and behaviour of Hector's dolphins (Cephalorhynchus hectori) at Banks Peninsula, New Zealand, made during photo‐ID surveys from 2003 to 2007. Aggregations of dolphins, typically involved in what we assumed to be foraging behaviour, were observed following small inshore trawlers year‐round. Group size was larger for aggregations of dolphins following trawlers (mean ± SE = 22.9 ± 1.3, n = 83) than for non‐trawler groups (3.7 ± 0.2, n = 439), and dolphins were typically in a more “excited” state, frequently exhibiting aerial and sexual behaviours. We suggest that trawlers increase the availability of prey for Hector's dolphins and hence foraging behind trawlers is an energetically favourable activity. However, following trawlers probably also increases the risk of being caught in trawl nets, compounding the threats faced by this endangered species.  相似文献   
133.
To establish a base line against which future pollution may be measured, eight common commercial species of New Zealand sea fish were analysed for cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc. One sample of edible muscle tissue was analysed for each of 70 samples of each species. The internal organs of up to five specimens of each species were also analysed. The fish studied were: kahawai, Arripis trutta, trevally, Caranx lutescens, tarakihi, Cheilodactylis macropterus, snapper, Chrysophrys auratus, moki, Latridopsis ciliaris, hapuku, Polyprion oxygeneios, kingfish, Seriola grandis and gurnard, Trigla kumu.

Although, none of the edible parts of the fish appeared to have trace element levels likely to be a public health problem (cadmium 0.002–0.02 ppm, chromium 0.01–0.04 ppm, copper 0.04–0.95 ppm, iron 0.9–13.5 ppm, lead ‘ 0.14–0.95 ppm, manganese 0.04–2.00 ppm, nickel 0.01–0.08 ppm, zinc 2.0–36.0 ppm), some of the organs (particularly the liver) had relatively high concentrations of elements such as cadmium (up to 54 ppm). Only if some industry were to seek to exploit internal organs of fish for human consumption would such levels become important. There was some evidence for a relationship between trace element concentrations and fish size for copper in kingfish and snapper, iron in hapuku, manganese in gurnard, and for zinc in kingfish and tarakihi. Some element pairs such as copper and zinc, iron and manganese, appeared to have concentrations which were mutually related. It was assumed that the elemental concentrations reported represent natural levels and are not the result of significant man‐made pollution because there are no major industries or large urban centres adjacent to the fishing grounds.  相似文献   
134.
Grab samples were taken from a population of Pectinaria australis Ehlers in Tasman Bay, New Zealand, at intervals over a 2‐year period, March 1971 to March 1973. Settlement occurred in summer with the new recruits showing rapid growth and heavy mortality, giving an apparent life cycle time of 1 y. The population density varied greatly over short distances at one time, presumably due to random settlement of aggregations of larvae from the plankton.  相似文献   
135.
From a trawling at 448–512 m in Palliser Bay, Cook Strait, New Zealand, molluscs associated with. Tertiary siltstone concretions and with a large colony of Goniocorella dumosa (Alcock) are listed. A juvenile Acesta, extremely tall and extremely broad forms of Emarginula striatula Quoy & Gaimard, and the animals of Stilifer neozelanica Dell and of Waipaoa marwicki Dell are described. Sculptifer, a new genus provisionally included in the Fossaridae, is proposed for Stilifer neozelanica. New species of Danilia and Pholadidea are described and their relationships discussed. Emarginula lophelia Beu, 1967 is synonymized with E. striatula Quoy & Gaimard, 1834, and the recent New Zealand forms of Emarginula are reviewed.  相似文献   
136.
Growth of the red gurnard, Chelidonichthys kumu (Lesson and Garnot), from Pegasus Bay, Canterbury, was measured during 1966–67. Otoliths were used as an indicator of fish growth; mean length‐at‐age data were obtained from back‐calculated fish lengths at the time of formation of successive annual rings in the otoliths. Growth in length was found to be adequately expressed by the von Bertalanffy growth equation :

lt = 52.0 [1 ‐ e0.406 (t‐o.291)]

(where lt is the fork length in cm at age t). The length: weight relationship was:

w = 78.56 × 10‐4 l 3.072

(where w is the weight in grams). From this relationship, growth in weight was described by the equation:

wt = 1469 [1 ‐ e‐0.406 (t‐0.291)]3.  相似文献   
137.
全球气候变化影响着海洋生态系统的多个方面,而鱼类群落结构对气候变化的响应机制是探索海洋生态系统演变规律的关键点之一。本文结合国内外相关研究成果,概述了气候变化引起的温度、盐度、CO2浓度、海平面高度、溶解氧以及海流等的改变对鱼类群落结构的影响,并以太平洋十年涛动(Pacific Decadal Oscillation,PDO)和厄尔尼诺−南方涛动(El Niño Southern Oscillation,ENSO)等典型气候现象为例,探讨了鱼类群落对典型气候现象的响应,讨论了需要解决的重点问题,以期为科学应对气候变化和制定海洋生物多样性保护策略提供依据。  相似文献   
138.
We investigated the effect of the replacement of dietary fish oil with vegetable oils on the growth and flesh quality of large yellow croaker(Larmichthys crocea). The basal diet(FO) was formulated to contain 66.5% fish meal and 6.4% menhaden fish oil; whereas the other 3 experimental diets were formulated by replacing the fish oil with 50% soybean oil(SO50), 100% soybean oil(SO100) and 100% palm oil(PO100), respectively. The 4 diets were randomly assigned to 4 floating sea cages(3.0 m × 3.0 m × 3.0 m), and each was stocked with 250 fish individuals with an initial average weight of 245.29 g ± 7.45 g. The fish were fed to apparent satiation twice a day at 5:00 and 17:00, respectively, for 12 weeks. Experimental analysis showed that the specific growth rate of fish fed SO50 or PO100 were significantly higher than that of fish fed FO or SO100(P0.05), and crude lipid contents of ventral muscle and viscera were significantly lower in fish fed FO than in those fed the other 3 diets(P0.05). No significant differences in condition factor, viscerosomatic index, hepatosomatic index, gutted yield and colorimetric values of fish among the dietary treatments were observed(P0.05). Compared to FO diet, SO50, SO100 and PO100 diets led to substantial decreases in the liquid loss and water loss from fresh fillets(1 d, 4℃)(P0.05). Similarly, thiobarbituric acid reactive substance(TBARS) values of fillets under different storage conditions(1 d, 4℃; 7 d, 4℃; 4 weeks,-20℃; 8 weeks,-20℃) decreased significantly after partial or complete replacement of fish oil with vegetable oils. These findings indicated that the growth performance and selected flesh quality properties(liquid holding capacity and TBARS value) of large yellow croaker were substantially improved by replacing dietary fish oil with vegetable oils.  相似文献   
139.
The U.S. National Oceanic and Atmospheric Administration implemented market-based fishery management in the New England groundfishery as catch shares, controlling aggregate harvests through tradable annual catch quotas allocated to fishing groups called sectors. Policy supporters assert that resulting markets raise conservation incentives. In compliance with the Magnuson–Stevens Fishery Conservation and Management Act, species assessments permit catch shares to replace more spatially and temporally specific constraints on fishing gear, time, areas, and daily harvest limits. Qualitative evidence from field interviews and participant observation questions the efficacy of catch shares. Fishing industry members observe that increased presence of large trawl vessels in previously protected areas damages fish subpopulations and benthic habitat. Regulatory bioeconomic models fail to consider these lay observations. The consequent inability of quota markets to recognize the materiality of human–environment relationships at the spatiotemporal scales of fishing activity, and to internalize associated externalities, may have devastating consequences for the fishery.  相似文献   
140.
Abstract Zinc (Zn) and copper (Cu) concentrations were determined in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five commercial fish species (mullet Liza haematocheilus, flathead Platycephalus indicus, mackerel Scomberomorus niphonius, silver pomfret Pampus argenteus, and sea bass Lateolabrax japonicus) from Laizhou Bay in the Bohai Sea. Metal bioaccumulation was highest in the metabolically active tissues of the gonads and liver. Bioconcentration factors for Zn were higher in all tissues (gonads 44.35, stomach 7.73, gills 7.72, liver 5.61, skin 4.88, and muscle 1.63) than the corresponding values for Cu (gonads 3.50, stomach 3.00, gills 1.60, liver 5.43, skin 1.50, and muscle 0.93). Mackerel tissues accumulated metal to higher concentrations than did other fish species, but bioaccumulation levels were not significantly correlated with the trophic levels of the fish. Zn and Cu concentrations in the tissues were generally negatively correlated with fish length, except for a few tissues of sea bass. Risk assessment based on national and international permissible limits and provisional tolerances for weekly intake of Zn and Cu revealed that the concentrations of these two metals in muscle were relatively low and would not pose hazards to human health.  相似文献   
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