Scallops: Biology, Ecology and Aquaculture (eBook)

Cover 1
Title page 4
Copyright 5
Dedication 6
Preface 8
Preface from First Edition 10
List of contributors 12
Table of Contents 16
1 New Phytogenies of the Pectinidae (Mollusca: Bivalvia): Reconciling Morphological and Molecular Approaches 42
Introduction 42
Molecular genetic studies 42
Methods and materials 48
New observations 51
Subfamily Camptonectinae Habe, 1977 51
Subfamily Palliolinae Korobkov in Eberzin, 1960 51
Tribe Pseudentoliini, new tribe 53
Tribe Adamussiini Habe, 1977 54
Tribe Eburneopectinini, new tribe 55
Tribe Serripectinini, new tribe 56
Tribe Palliolini Korobkov in Eberzin, 1960 58
Tribe Mesopeplini, new tribe 61
Origins of the Decatopecten and Pecten Groups 63
Eastern Atlantic Pecten 69
Conclusions 71
Acknowledgments 73
References 73
Appendix 84
2 Development, Physiology, Behaviour and Ecology of Scallop Larvae 86
Introduction 86
Scallop life history characteristics 86
Larval development 96
Embryogenesis 96
Development of the larval shell 97
Organogenesis 100
Development of ciliation, the prototroch and the velum 100
Larval mantle 105
Musculature 105
Digestive tract 109
Sense organs 109
Apical organ 109
Statocysts 114
Eye spots 114
Mantle ciliation 115
Foot 118
Nervous system 119
Other organs 120
Metamorphosis 120
Comparative anatomy 122
Functional morphology 125
Locomotion 125
Feeding 126
Respiration 126
Sensory reception 127
Physiology and effects of environmental variables 128
Energy reserves and feeding 128
Respiration 129
Growth 130
Biochemical events during metamorphosis 131
Behaviour and larval distribution 131
Characteristics of locomotion during larval development 131
Responses to stimuli 132
Distribution of larvae 135
Development and the larval environment 139
Tolerance of environmental variables. 140
Rearing methods 142
Spawning and manipulation of zygotes 142
Feeding 143
Control of disease in cultures 144
Collection of spat from wild stocks 145
References 146
3 Structure and Function in Scallops 164
Introduction 164
An overview of the scallop body 164
The mantle and its derivatives 167
Gross functional anatomy 168
Microanatomy and functions 171
Pallial organs and particle processing 173
Gills 173
Gill axis and arch 176
Principal filaments and dorsal expansion 17
Ordinary filaments 178
Haemolymph circulation in the gill 182
Particle processing on the gill 182
Particle selection at the gill 182
Particle retention lower size limit 184
Ingestion volume regulation on the gill 184
Labial palps and lips 185
Labial palps 185
Particle processing on the labial palps 185
Lips 188
Digestive system and digestion 191
Mouth and oesophagus 191
Stomach, crystalline style and gastric shield 191
The digestive gland 195
Intestine, rectum and anus 198
Digestive sites and postingestive selection 200
Cardio-Vascular system 200
General circulation 201
The arterial system 201
Anterior aorta 201
Posterior aorta 201
The venous system 203
The heart 203
The ventricle 203
The auricles and their excretory structures 204
Structure and ultrastructure of heart cells 204
Contraction 206
Refilling 206
Coordination of alternate AV beat 207
Pacemaker mechanism 207
Regulation of pacemaker 208
Haemolymph 208
Plasma 209
Haemocytes 209
Haemocyte types 210
Functions of haemocytes 210
Excretory system 211
Pericardial (auricular) glands 211
Kidney 213
Functions of the kidney and pericardial glands 214
Reproductive system 217
Sexuality: Gonochory, hermaphroditism and their variants 217
Origin and formation of the gonad 217
Anatomy, histology and ultrastructure of the adult gonad 218
Outer epithelium 218
Perigonadal connective tissue 220
Inter-acinal connective tissue 220
Haemolymph sinuses 220
Acini 221
Evacuating ducts. 221
Gametogenesis 221
Oogenesis 221
Premeiotic stage 221
Previtellogenic stage 222
Vitellogenesis and metabolite transport to the oocyte 222
Oocyte atresia 226
Spermatogenesis, spermatozoon ultrastructure and taxonomy 229
Fertilisation 231
Nervous and sensory systems 232
General organisation of the nervous system and functional anatomy of principal ganglia 232
Cerebral and pedal ganglia 232
The parietovisceral ganglion and its nerves 232
Histology and neurosecretions of the ganglia 237
The circumpallial nerve 239
Sensory structures 239
Visual system 239
Epithelial sensory cells and tentacles 239
Abdominal sense organ 240
Osphradia 242
Statoreceptors 245
Neurotransmitters and neurohormones 245
Foot-byssal complex 247
External morphology and development of the foot-byssal complex 248
Anatomy and histology of the foot-byssal gland complex 249
The protein gland 249
The enzyme gland 249
The byssus 251
Functioning of the foot-byssal complex 251
Acknowledgments 251
References 252
4 Scallop Adductor Muscles: Structure and Function 270
Introduction 270
Structure of the striated adductor muscle 272
Fibre microanatomy 272
Actin and thin filament structure 274
Thick filament structure 281
Structure of the smooth adductor muscle 284
Fibre microanatomy 284
Thin filament structure 286
The structure of paramyosin-rich thick filaments 288
Myosin 294
Function of the striated adductor 312
Mechanics 312
The interaction of myosin with actin 313
The crossbridge cycle 318
Myosin-linked regulation 323
Function of the smooth adductor 330
Physiology 330
Catch mechanism 333
Achievements and goals 337
Acknowledgments 339
References 339
5 Neurobiology and Behaviour of the Scallop 358
Introduction 358
The visual system. 358
Functional anatomy of the eyes 358
Retinal physiology 363
Receptor potential biophysics 365
Anatomy and physiology of vision in the central nervous system 369
Visual behaviours 373
The locomotory system 376
Escape responses and swimming 376
Sensory and motor functions of the mantle 382
Innervation and neuromuscular physiology of the adductor muscle 386
Coordination of locomotory behaviour by the central nervous system 389
Acknowledgments 393
References 393
6 Reproductive Physiology 398
Introduction 398
Gametogenic cycles 399
Definition 399
Means of assessment 399
Visual observation 401
Gonad mass and index 401
Histology 408
Abundance of larvae and spat 410
Variations in gametogenic cycles 411
Intra-specific variations 411
Inter-specific variations 416
Regulation of gametogenic cycles 416
Gametogenesis and fecundity 417
Exogenous regulation 417
Endogenous regulation 422
Spawning and spawning synchrony 426
Exogenous regulation 426
Endogenous regulation 430
Energy metabolism 431
Tissue weights and indices 432
Tissue biochemical composition 433
Physiological indices 436
Radiotracer experiments 439
Ultrastructure and histochemistry 439
Mechanisms 441
Applications to aquaculture 442
Broodstock conditioning 442
Spawning 444
Larval growth and survival 444
Summary 445
Gametogenic cycles 445
Regulation of gametogenesis 445
Energy metabolism 446
Applications to aquaculture 447
References 447
7 Physiology: Energy Acquisition and Utilisation 458
Introduction 458
Energy acquisition 458
Food sources 458
Feeding currents and mechanisms of particle capture 461
Particle retention efficiency 462
Feeding rates 465
Clearance rate in relation to food concentration 468
Influence of temperature on feeding rates 471
Pseudofeces production, pre- and post-ingestive particle selection 473
Absorption efficiency 477
Effects of suspended sediments on feeding and growth 480
Effects of flow on feeding and growth 486
Effects of harmful and toxic algae 488
Energy utilisation: Metabolic expenditure 494
Metabolic rate and oxygen availability 496
Metabolic cost of reproduction 499
Metabolic rate in relation to temperature and latitude 501
Metabolic rate in relation to activity levels 502
Anaerobic metabolism 504
Energy utilisation 508
Excretion and byssus secretion 508
Growth 509
References 515
8 Physiological Integrations and Energy Partitioning 534
Introduction 534
Energy balance, physiological integrations and the partitioning of energy between growth and reproduction 534
Energy budgets 534
Scope for growth 535
Growth efficiency and turnover ratio 535
Growth of shell and somatic tissue 536
Reproductive effort 537
Changes related to age of individuals 539
Scope for growth 539
Growth efficiency and turnover ratio 539
Somatic growth and maximum size 540
Somatic production and reproductive output 541
Reproductive effort 543
Environmental influence on production 545
Scope for growth and growth efficiency 545
Growth of shell and somatic tissue 547
Reproductive effort 550
Reproductive value and cost 552
Residual reproductive value 552
Reproductive cost 553
Population production 555
Acknowledgments 557
References 557
9 Nutrition in Pectinids 562
Introduction 562
Pectinid feeding 562
Nutritional requirements during reproductive conditioning 569
Nutritional requirements of the larvae 570
Post-metamorphic nutritional requirements 574
Summary 577
References 577
10 Genetics 584
Introduction 584
Chromosomal genetics and ploidy manipulation 585
Chromosome numbers and karyotypes 585
Ploidy manipulation 589
Genetic markers and population genetics 591
Genetic markers 591
Allozymes 592
DNA methods 592
DNA based markers 593
Restriction fragment length polymorphism (RFLP) 593
Random amplified polymorhic DNA (RAPDs) 593
Microsatellites 594
Amplified fragment length polymorphism (AFLP) 594
Mitochondrial DNA in scallops 595
Types of data produced by different markers 596
Analysis of data 596
Overall genetic variation 598
Genetic differentiation of populations 600
Placopecten magellanicus 600
Patinopecten (= Mizuhopecten) yessoensis 602
Pecten maximus 603
Aequipecten opercularis 604
Chlamys islandica 605
Chlamysfaneri 606
Mimachlamys varia 606
Euvola (Pecten) ziczac 606
Argopecten gibbus 606
The Argopecten irradians species complex 607
Genetic differences at species level and above 608
Heterozygote deficiency 609
Heterozygosity and growth 612
Quantitative genetics 616
Heritability and artificial selection 616
Inbreeding and hybridisation 618
Genome mapping and gene sequences 620
Conclusion 621
Acknowledgments 622
References 622
11 Diseases and Parasites of Scallops 636
Introduction 636
Microbial diseases 636
Viruses 636
Prokaryota 646
Vibrionaceae 646
Intracellular prokaryotes (Rickettsiales Chlamydiales and Mycoplasma)
Other bacterial pathogens of scallops 651
Bacterial management under hatchery conditions 652
Mycota 653
Protista 655
Sarcomastigpphorea (Amoebae and Flagellates) 655
Labyrinthomorpha (Thraustochytrids and Labythinuloids) 656
Apicomplexa 656
Perkinsorida 656
Eucoccidiia 658
Eugregarinida 659
Microspora 660
Ascetospora 661
Marteiliida 661
Balanosporida 661
Ciliates 662
Platyhelminths 664
Trematodes 664
Cestodes 667
Turbellaria 667
Nematodes 669
Polychaetes 670
Crustacea 673
Pinnotheriidae 673
Copepodidae 673
Gastropods 674
Algae 676
Foraminiferans 677
Porifera 677
Cnidaria 678
Non-Infectious diseases 679
Summary 679
Acknowledgments 680
References 680
12 Scallop Ecology: Distributions and Behaviour 692
Introduction 692
Geographical distribution 694
Geographical distribution of commercially important species 694
North Atlantic species 694
Pecten maximus and P. jacobaeus 694
Aequipecten opereularis 696
Mimachlamys varia 696
Placopecten magellanicus 696
Argopeeten irradians 698
Argopecten gibhvs 700
Sub-arctic species 700
Chlamys islandica 700
North Pacific species 702
Patinopecten caurinus 702
Mizuhopecten yessoensis 702
Pecten albicans, Mimachlamys nobilis and Chlamys farreri 703
Southern hemisphere species 703
Pecten fumatus 703
Mimachlamys asperrima and Equichlamys bifrans 704
Amusium balloti and A. pleuronectes 705
Pecten novaezelandiae 705
Argopecten purpuratus and A. ventricosus 706
Aequipecten tehuelchus 706
Zygochlamys patagonica 706
Factors affecting geographical distribution 707
Local distribution 710
Spatial distribution 710
Year-class separation 717
Factors affecting local distribution 718
Depth 719
Substrate type 719
Currents 720
Turbidity 721
Salinity 722
Competitors and predators 725
Scallop behaviour - aspects affecting distribution 730
Byssus attachment 730
Recessing 733
Orientation 736
Swimming 739
Reactions to predators 748
Dispersal and migrations 750
Further study 753
Acknowledgments 754
References 754
13 Scallops and Marine Contaminants 786
Introduction 786
Trace metals 787
Trace organics 789
Offshore oil and gas operations 791
Scallops as sentinel organisms 795
Acknowledgments 800
References 800
14 Dynamics, Assessment and Management of Exploited Natural Populations 806
Introduction 806
Spatial scales 806
Population structure and dynamics 810
Aggregate stocks 810
Patterns of fluctuation 810
Climatic forcing 812
Correlation between consecutive life-history stages 814
The relation between aggregate stock and settlement/recruitment 815
Macroscale 818
Patterns of connectivity: metapopulation structure 818
Metapopulation structure and geographic genetic differentiation 821
Larval retention/dispersal: mechanisms and oceanographic scenarios 823
Metapopulation models 825
Mesoscale 826
Persistence, extinction and resurgence of subpopulations 826
Relation between abundance and area occupied by a subpopulation 826
Microscale 827
Density, neighbourhoods and concentration 827
Concentration profiles 829
Density- vs. concentration-dependence compensation vs. depensation
The fishing process 836
Types of fishing gear used in scallop fisheries 837
Effort and fishing mortality 838
Effort data 838
Effort units 838
Components of fishing mortality under homogeneity assumptions 839
Relative fishing power and standardisation of effort 840
Spatial patterns of effort allocation 840
The depletion process 844
Vulnerability and selectivity 846
Gear performance 847
Incidental fishing mortality and sub-lethal damage 849
Assessment 852
Macroscale 852
Mesoscale 853
Estimation of aggregated abundance: methods based on sampling 853
Mapping 856
Methods based on modelling the depletion process 857
Microscale 860
Small-scale spatial data 860
Spatial pattern 861
Scaling problems 862
Management 864
Types of scallop fisheries 864
Overfishing 865
Growth overfishing: yield-per-recruit (Y/R) analysis 865
Recruitment overfishing 867
A special case: recruitment fisheries 870
Sustainability 871
The precautionary approach to fisheries management (PAFM) and risk assessment (RA) 871
Marine protected areas (MPAs) 873
Ecosystem management concerns 875
Strategic structures: use and property rights 876
Diversification of the resource-base 878
Tactics 879
Size limits 879
Quote regulations 881
Escapement regulations 881
Direct effort regulations 881
Rotation 882
Direct interventions to enhance productivity 883
Experimental management 885
Acknowledgments 885
References 885
Endnotes 908
15 Fisheries Sea Scallop, Placopecten magellanicus 910
Introduction 910
Distribution 912
History of fishery 915
Population biology 919
Growth and yield per recruit 921
Gear and boats 924
Exploitation and resource management 927
Outlook 936
References 938
16 Sea Scallop Aquaculture in the Northwest Atlantic 948
Introduction 948
History of sea scallop culture 949
Hatchery spat production 950
Broodstock conditioning 950
Spawning methods 951
Egg and larval development 951
Settlement and metamorphosis 952
Spat husbandry 952
Wild spat collection 953
Spat collection techniques 953
Settlement intensity 954
Maximising spat collection 955
Spat growth 957
Spat sorting 957
Intermediate culture 957
Growth 958
Stocking density 958
Depth 960
Season 960
Location 960
Survival 961
Gear selection 961
Strategies for intermediate culture 962
Final grow-out 963
Suspension culture 963
Bottom culture 963
Growth 964
Scheduling and strategies 965
Site selection 965
Environmental criteria 966
Temperature and salinity 966
Ice coverage 966
Wind 966
Bottom type 966
Turbidity 967
Biological constraints 967
Predators 967
Fouling organisms 967
Phycotoxins 967
Diseases and parasites 968
Products and marketing 969
Economics 969
Social issues 970
Future prospects 971
Acknowledgments 971
References 971
17 Bay Scallop and Calico Scallop Fisheries, Culture and Enhancement in Eastern North America 986
Introduction 986
Fisheries 986
Bay scallop, Argopecten irradians 986
Distribution 986
Biology 989
Fishery 991
Calico scallop, Argopecten gibbus 993
Distribution 993
Biology 994
Fishery 996
Aquaculture and enhancement 999
Future 1002
References 1002
18 Scallops of the West Coast of North America 1006
Introduction 1006
Fisheries 1008
Weathervane scallop 1008
Biology 1008
Fishery 1012
Gear 1014
Management 1014
Rock scallop 1014
Biology 1015
Fishery 1016
Pink and spiny scallops 1016
Biology 1016
Fisheries 1018
Management 1020
Aquaculture 1020
Pink and spiny scallops 1021
Weathervane scallop 1021
Rock scallops 1022
Japanese weathervane scallop 1023
Pacific calico scallop 1024
Future 1024
Acknowledgments 1025
References 1025
19 The European Scallop Fisheries for Pecten maximus, Aequipecten opercularis and Mimachlamys varia 1032
Introduction 1032
Biology and ecology 1034
The great scallop, Pecten maximus (L.) 1034
The queen scallop, Aequipecten opercularis (L.) 1047
The black or variegated scallop, Mimachlamys varia (L.) 1052
Fisheries 1055
Isle of Man 1058
Scotland 1064
England and Wales 1066
Northern Ireland 1068
Republic of Ireland 1068
France 1070
Spain 1072
The future 1072
Acknowledgments 1076
References 1076
20 European Aquaculture 1100
Introduction 1100
Pecten maximus 1101
Aequipecten opercularis 1103
Chlamys varia 1104
Summary 1104
References 1104
21 Scandinavia 1108
Introduction 1108
Chlamys islandica 1108
Biology 1108
Fishery 1114
Aquaculture 1117
Pecten maximus 1118
Biology 1118
Fishery 1119
Aquaculture 1120
Aequipecten opercularis 1126
Acknowledgments 1127
References 1127
22 Japan 1134
Introduction 1134
Patinopecten (Mizuhopecten) yessoensis 1140
Biology 1140
Fishery 1145
Culture 1152
Seed production 1152
Spat collection 1152
Intermediate culture 1157
Hanging culture 1157
Fouling 1159
Sowing culture 1161
Enemy clearance 1161
Seed sowing 1161
Care 1162
Recapture 1162
Value 1165
Processing 1168
Occurrence of shellfish poisoning 1171
Future. 1171
Technology 1171
Control of culture 1174
Cost-reduction 1174
Concept 1174
Pecten albicans 1175
Biology 1175
Fishery 1175
Culture 1176
Chlamys (Mimachlamys) nobilis 1176
Biology 1176
Culture 1176
Acknowledgments 1177
References 1177
23 Scallop Culture in China 1184
Introduction 1184
Zhikong scallop 1187
Shell morphology 1187
Distribution 1187
Growth 1188
Reproduction 1190
Other scallop species 1192
Huagui scallop 1192
Non-native species 1193
Fishery 1194
Aquaculture 1195
Species and history 1195
Collection of natural seed for Zhikong scallop 1196
Hatchery production of bay scallop 1196
Grow-out 1199
Harvest, processing and marketing 1201
Acknowledgments 1201
References 1202
24 Scallops Fisheries and Aquaculture of Northwestern Pacific, Russian Federation 1204
Introduction 1204
Taxonomic status 1204
Biology and ecology 1205
Chlamys albida (Common names: white scallop and commercial scallop) 1205
Chlamys asiatica (Common name: Asiatic scallop) 1207
Chlamys behringiana (Common name: Bering Sea's scallop) 1208
Chlamys chosenica (Common names: Pink scallop and White-pink scallop) 1209
Chlamys farreri (Common names: Japanese scallop, Chinese scallop, Farrer's scallop, Akazara scallop) 1211
Chlamys swifti (Common name: Swift's scallop) 1213
Delectopecten randolphi (Common name: Randolph's scallop) 1215
Mizuhopecten yessoensis (Common Names: Yesso scallop, Ezo scallop, Giant scallop, Japanese scallop, Russian scallop, Primorsky scallop and Common scallop) 1215
Total populations and biomass 1216
Distribution in Primorye 1217
Distribution over depths 1217
Age structure of scallop settlements 1217
Scallop growth 1218
Sex structure of settlements 1219
Replenishment 1222
Spawning 1222
Larvae morphology 1223
Development in plankton 1223
Migration behaviour 1225
Risk factors 1225
Abiotic factors 1225
Storms 1225
Predators 1226
Parasites 1228
Bacterial contamination 1230
Epibionts 1230
Fishing and aquaculture 1230
Fishing 1230
History 1230
Fishing gear 1232
Yesso scallop landings 1232
Primorsky territory 1232
Sakhalin-Kurile region 1233
Yesso scallop commercial stock 1233
Primorsky territory 1233
Sakhalin-Kurile region 1233
AnivaBay 1235
Terpenie Bay 1235
Kuriles 1235
Commercial Chlamys scallops 1235
Primorye 1235
Kurile Islands 1236
In Bering Sea 1237
Other Chlamys species 1237
Chlamys farreri 1237
Chlamys swifti 1237
Aquaculture 1237
History 1237
Present situation 1238
Marketing 1239
The culture methods 1239
Spat collection 1239
Intermediate culture 1240
Transport of scallop seed 1240
Sowing or on-bottom culture 1241
Hanging or off-bottom culture 1241
Obstacles to mariculture development 1242
Ecological constraints associated with cultivation 1243
Predation 1243
Epibionts 1243
Biofouling of cultivation structures 1244
Effect of scallop mariculture on coastal ecosystems 1245
Future prospects 1252
Acknowledgments 1254
References 1254
25 Scallop Aquaculture and Fisheries in Brazil 1266
Introduction 1266
Nodipecten nodosus - biology, aquaculture and fisheries 1268
Taxonomy and distribution 1268
Ecology 1269
Reproduction 1272
Aquaculture 1273
Status 1273
Culture technology 1274
Wild seed collection 1274
Hatchery production 1275
Growout 1277
Constraints 1280
Fisheries and marketing 1280
Future prospects 1281
Euvola (Pecteri) ziczac - biology, aquaculture and fisheries 1281
Taxonomy and distribution 1281
Ecology 1282
Reproduction 1282
Aquaculture 1283
Status 1283
Culture technology 1283
Wild seed collection 1283
Hatchery production 1283
Growout 1284
Constraints 1284
Fisheries 1284
Future prospects 1285
Acknowledgments 1285
References 1286
26 Argentina 1292
Introduction 1292
The Tehuelche scallop, Aequipecten tehuelchus 1292
Biology 1292
Population dynamics 1298
Fisheries 1299
The inshore dredge fishery of San Matias Gulf (Rio Negro Province) 1299
The commercial diving fishery of San José Gulf (Chubut Province) 1302
Aquaculture 1304
Spat collection 1304
Vertical distribution of settlement 1304
Temporal variation in settlement 1304
Type of collector 1304
Location 1306
Influence of depth, type of collector and location on the average size of the 'seed' 1306
Growth in suspended structures of spat obtained from collectors 1307
Larval culture in the laboratory 1309
Prospects and problems 1309
The Patagonian scallop, Zygochlamys patagonica 1310
Biology and ecology 1310
Population dynamics and stock assessment 1314
The fishery 1316
Exploratory surveys and experimental fishing programs 1316
Management 1317
Development of the fishery 1318
Observers program 1321
Ecological effects of fishing 1322
Marketing 1324
Acknowledgments 1324
References 1324
27 Scallop Fishery and Aquaculture in Chile 1334
Introduction 1334
Species description 1334
Argopecten purpuratus (Lamarck 1819) the northern scallop 1336
Zygochlamys patagonica (King and Broderip 1831) the southern scallop 1336
Chlamys vitrea (King & Broderip, 1831) the southern scallop
Fisheries 1337
Argopecten purpuratus, the northern scallop 1337
Chlamys vitrea and Zygochlamys patagonica, the southern scallop 1339
How scallop aquaculture started in Chile 1340
Aquaculture production 1342
Production stages 1344
Hatchery broodstock conditioning and spawning 1344
Larval stage 1344
Settlement, metamorphosis and postlarval stage 1345
Seed supply 1346
Ongrowing stage 1346
Constraints and opportunities for northern scallop hatcheries 1347
Interaction between natural beds and aquaculture 1348
Recovery of a natural bed of Argopecten purpuratus 1349
Final overview and projections of Chilean scallop farming 1349
Acknowledgments 1352
References 1352
28 Venezuela 1356
Introduction 1356
Distribution, habitat and reproduction 1356
Evvola (Pecten) ziczae 1356
Argopecten nucleus 1360
Nodipecten (Lyropecteri) nodosus 1360
Amusium papyraceum and Amusium laurenti 1361
Fisheries 1361
Aquaculture 1363
Euvola ziczac 1363
Gonad maturation and spawning 1363
Spat production 1363
Grow-out 1364
Nodipecten nodosus 1367
Gonad maturation and spawning 1367
Spat production 1367
Grow-out 1367
Argopecten nucleus 1370
Perspectives for culture 1371
References 1373
29 Mexico 1378
Fishery 1378
Introduction 1378
Species and distribution of scallops 1379
History of the fishery 1380
Status of the resource 1381
Reproductive biology 1381
Size at maturity 1381
Fecundity 1382
Maturity and spawning 1382
Population biology 1385
Abundance and density 1386
Exploitation of the resource 1388
Fishing areas 1388
Fishing seasons 1389
Fishing operations and results 1390
The market value-landings data from 1970 to 2000 1390
Constraints 1391
Pollution 1391
Biological constraints 1393
Predation 1394
Resource management constraints 1395
Harvesting and transporting 1395
Methods 1395
Marketing 1396
Expected future 1397
Aquaculture 1398
Introduction 1398
Species 1399
History 1399
Hatchery techniques 1400
Conditioning 1400
Induction of spawning and fertilisation 1401
Larval culture and metamorphosis 1402
Genetic enhancement 1407
Selection 1407
Crossbreeding 1407
Triploidy 1408
Antibiotics 1409
Natural spat 1409
Methods employed 1409
Spat collection 1410
Growth 1413
Suspended cultures 1413
Bottom cultures 1416
Factors influencing growth 1417
Mortality 1418
Suspended culture 1418
Bottom culture 1419
Constraints 1420
Future prospects 1420
References 1421
30 Scallop Fisheries, Mariculture and Enhancement in Australia 1432
Introduction 1432
History of the fisheries 1433
Biology of target species 1436
Pecten fumatus 1436
Distribution and life cycle 1436
Mortality 1437
Monitoring, abundance and population dynamics 1438
Amusium balloti 1439
Distribution and life cycle 1439
Mortality 1439
Monitoring, abundance and population dynamics 1440
Fisheries and their management 1441
Pecten fumatus 1441
Regulation 1441
Environmental management and sustainability issues 1443
Amusium balloti 1444
Regulation 1444
Environmental management and sustainability issues 1445
Culture of scallops in Australia 1446
Pecten fumatus 1446
Tasmania 1446
Spat production 1446
Culture operations 1446
Victoria 1447
New South Wales 1447
South Australia 1448
Amusium balloti 1448
Summary 1448
Acknowledgments 1449
References 1449
31 New Zealand 1454
Introduction 1454
Biology 1454
Morphology 1454
Distribution 1454
Life cycle 1455
Growth rates 1456
Mortality 1456
Commercial fishing 1459
Development of the scallop fishery 1459
Capture methods 1459
Management 1461
The Challenger fishery 1461
The Northland and Coromandel scallop fisheries 1462
Recreational fishing 1463
Aquaculture and enhancement 1463
Future developments 1464
Acknowledgments 1465
References 1465
Species index 1468
General index 1480