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Pueruli and post‐pueruli, early juveniles and sub‐adults of the spiny lobster, Panulirus homarus and juveniles of P. ornatus were grown in different floating sea cages along the southeast coast of India from May 2003 to May 2007. The first type of cage had a galvanised iron pipe frame (2.0 m × 2.0 m × 1.2 m) with steel woven mesh and four inner detachable compartments (0.75 m × 0.75 m × 1.10 m). Fibre‐reinforced plastic was used subsequently to fabricate cages (1 m × 1 m × 1 m). Pueruli and post‐pueruli of P. homarus (1.58 ± 0.62 g SD), stocked at 60 individuals/m2, grew to an average weight of 123.10 ± 26.22 g in 266 days with a survival rate of 70%. Sub‐adults of P. homarus with an average weight (± SD) of 123.61 ± 29.26 g reached 341.25 ± 46.22 g in 225 days at a stocking density of 21 individuals/m2 with a survival of 73 ± 6%. The post‐pueruli grew by 0.46 ± 0.10 g per day with a specific growth rate (SGR) of 1.64, whereas sub‐adults had a growth rate of 0.97 ± 0.20 g per day with a SGR of 0.43. At a higher stocking density of 80 individuals/m2, juveniles (51.83 ± 10.32 g and 58.20 ± 28.22 g) of P. homarus recorded growth rates of 0.86 ± 0.25 (SGR 0.82) and 0.97 ± 0.34 g (SGR 0.96) per day. This study indicates that post‐pueruli of P. homarus can be grown to over 200 g in 12 months and up to 350 g in 16 to 17 months in sea cages. Juveniles (average weight 76.35 ± 34.50 g) of P. ornatus, reared with P. homarus at a stocking density of 80 individuals/m2, recorded a weight gain of 139 g in 155 days at arate of 0.89 ± 0.32 g per day with an SGR of 0.67. Marine live clam, Donax spp., was the main feed supplemented with the gastropod, Xancus pyrum, the green mussel, Perna viridis, marine crab (Charibdis sp.), squid (Loligo sp.), and fish such as clupeids and Leognathus sp. Pueruli and post‐pueruli settled in large numbers (up to 35 individuals/month in one cage) both inside and outside the cages.  相似文献   
2.
Analysis of 326 stomachs of the kahawai, Arripis trutta (Bloch and Schneider), from Wellington Harbour showed that the fish is a voracious carnivore which feeds mainly on fishes and to a lesser extent on planktonic crustaceans. The kahawai is principally a pelagic feeder, but occasionally takes food from the sea bottom; it appears to feed on those fishes which are locally most abundant, and follows shoals of small fish on which it preys. Small kahawai below 100 mm in length eat mainly copepods.  相似文献   
3.
Settlement of puerulus‐stage New Zealand red rock lobsters (Jasus edwardsii) and abundance of the first three juvenile cohorts were measured from 1981 to 1989 near Halfmoon Bay, Stewart Island. Puerulus settlement on subtidal collectors shows great annual variation. Juvenile abundance, estimated from the number caught in annual diver collections, shows less variation. One‐year‐olds appear less vulnerable to diver sampling than older juveniles. Abundance of 2‐ and 3‐year‐olds is highly correlated with puerulus settlement 2 and 3 years previously. Survival between puerulus and 1+ stages appears to be density‐dependent, but survival of older juveniles does not. Size is inversely related to abundance in 3+ females but not in the other cohorts, suggesting density‐dependent growth between ages 2 and 3. Puerulus settlement rates and processes on shallow inshore reefs appear to be important in determining recruitment strength in this species.  相似文献   
4.
Phyllosoma larvae collected to date in Japanese and Taiwanese waters have been classified into two genera (Linuparus, Panulirus) of the Palinuridae, four genera (Ibacus, Parribacus, Scyllarides, Scyllarus) of the Scyllaridae, and one genus (Palinurellus) of the Synaxidae. However, phyllosoma larvae of three Scyllarus species (S. bicuspidatus, S. cultrifer, S. kitanoviriosus) are absolutely dominant among the larvae collected in the waters. Scyllarus larvae are abundant in coastal waters while those of Panulirus are often collected in offshore/oceanic waters. Based on previous and ongoing studies dealing with spatial distributions of phyllosoma larvae in Japanese and Taiwanese waters, it appears that phyllosoma and nisto larvae of the Scyllarus are retained within coastal waters north of the Kuroshio Current. On the other hand, the life history of the Panulirus (particularly P. japonicus) may be completed within the Kuroshio Subgyre: their phyllosoma larvae may be flushed out from coastal waters into the Kuroshio, then transported through the Counter Current south of the Kuroshio into the water east of Ryukyu Archipelago and Taiwan where they attain the subfinal/final phyllosoma or puerulus stages, once again entering the Kuroshio and dispersing into coastal waters. This revised version was published online in July 2006 with corrections to the Cover Date. An erratum to this article is available at .  相似文献   
5.
The physical and chemical features of Pupu Springs (40 51’ S, 172° 46’ E), near Takaka, the largest cold springs in New Zealand and one of the largest in the world, were investigated by scuba diving. The springs have a maximum depth of 6.9 m and a mosaic of substrate types (bedrock, boulders, and gravel). The temperature of the springs water is constant at 11.7°C, water velocities are generally moderate to very strong (25–100 cm.s‐1), and average water discharge is about 9.6 m3.s‐1. Mean holding time for water in the springs is 4.4 min. The water is extremely clear, with a vertical extinction coefficient (log10) of 0.09. The springs water flows from an artesian basin in Arthur Marble and is low in dissolved oxygen. The water is rich in calcium (64 g.m‐3), with a high specific conductivity (65 mS.m‐1). Information on water temperature, discharge, and chemistry is provided for five other cold springs in New Zealand: Hamurana Springs, Rotorua; Otangaroa Springs, near Putaruru; Three Springs, near Fairlie; Western Springs, Auckland; and a spring at Lake Hayes, Queenstown.  相似文献   
6.
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   
7.
Trends in the abundance, size and growth of newly settled pueruli and early juveniles of the rock lobster Jasus lalandii were determined from samples obtained from mesh bags used for oyster mariculture in Saldanha Bay, South Africa. Totals of 3 842 lobster pueruli and 10 158 juveniles were captured between August 2005 and June 2006, and distinct puerulus settlement events were identified in November and January. Juveniles also peaked during these months as well as in March. The size of newly settled pueruli increased significantly between October and March. The carapace length (CL) of pueruli and juveniles overlapped between 8.5 mm (smallest juvenile) and 10.4 mm (largest puerulus), and 50% of pueruli moulted into juveniles by 9.5–9.6 mm CL. There was a size progression in juveniles, with larger individuals in February and March reflecting an accumulation of juveniles from the earlier settlement events. The estimated growth increment from puerulus to first juvenile instar was 0.5–1.5 mm (4.9–16.1%), increasing to 1.4–2.5 mm (14.4–23.3%) for the second instar. Recruitment of J. lalandii pueruli occurred during periods when strong southerly winds prevailed, which results in a general offshore movement of surface waters along the West Coast and upwelling of cold nutrient-rich bottom waters. However, specific settlement events appeared to coincide with a change in wind direction, reduction in upwelling strength and increase in surface water temperatures, implying that larvae may take advantage of landward movements of surface waters during downwelling, or reversal of upwelling, to return them to shallow coastal waters.  相似文献   
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