Ecology and conservation of fishes

Tyus Written as a stand-alone textbook for students and a useful reference for professionals in government and private agencies, academic institutions, and consultants, Ecology and Cons

Ecology and Conservation of Fishes

Harold M Tyus

Written as a stand-alone textbook for students and a useful reference for professionals

in government and private agencies, academic institutions, and consultants, Ecology

and Conservation of Fishes provides broad, comprehensive, and systematic coverage of

all aquatic systems from the mountains to the oceans The book begins with overview

discussions on the ecology, evolution, and diversity of fishes It moves on to address

freshwater, estuarine, and marine ecosystems and identifies factors that affect the

distribution and abundance of fishes It then examines the adaptations of fishes as a

response to constraints posed in ecosystems The book concludes with four chapters on

applied ecology that discuss the critical issues of management, conservation, biodiversity

crises, and climate change

Features:

• Considers the role of fishes in the structure and function of freshwater, estuarine,

and marine ecosystems

• Discusses major changes in aquatic systems due to human impacts

• Provides in-depth coverage of the causes of the increasing number of endangered

species in freshwater systems and declines of commercial fisheries in marine systems

• Presents case studies from all major aquatic systems to reinforce concepts

• Includes a 16-page, full-color insert consisting of 141 figures

• Offers an “Ecological Concepts” section in appropriate chapters to encourage students

to apply theoretical concepts to real-world situations

• Contains a Glossary, a Lexicon of Greek and Latin Word Roots, and an Appendix on

Fish Identification to help students master the text material

Major marine fisheries have collapsed, and there are worldwide declines in freshwater fish

populations Fishery scientists and managers must become more effective at understanding

and dealing with resource issues If not, fish species, communities, and entire ecosystems

will continue to decline as habitats change and species are lost Ecology and Conservation

of Fishes has taken a historical and functional approach to explain how we got where we

are, providing old and new with a better foundation as ecologists and conservationists, and

most importantly, it awakens senses of purpose and need Past management practices are

reviewed, present programs are considered, and the need for incorporating principles of

applied ecology in future practices is emphasized.

www.ebook777.com

Ecology and Conservation of Fishes

HAROLD M TYUS

Ecology and Conservation of Fishes

Cover: Center photo of two biologists and an endangered pallid sturgeon is given courtesy of Steven Krentz, U.S Fish

and Wildlife Service The remaining eight images are from various sources that are acknowledged elsewhere in this book.

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This book is dedicated to W L Minckley, William M. Lewis Jr., and Ptychocheilus lucius, who gave me the insight, fortitude, and means to accomplish this work.

Contents

Preface xix

Acknowledgments xxi

Use.and.Features.of.the.Book xxiii

Author.Biography xxv

A.Lexicon.of.Greek.and.Latin.Word.Roots.Used.in.this.Text xxvii

Part I Introduction Chapter.1 Ecology.of.Fishes:.Content.and.Scope 3

History.of.Ecology 3

Fish.Ecology.Explored 4

What.Is.a.Fish? 5

Fish:.The.First.Vertebrate 7

Summary 7

Part II Evolutionary Ecology of Fishes Chapter.2 Aquatic.Evolution,.Origins,.and.Affinities 11

Aquatic.Evolution 11

Evolutionary.Ecology 11

Origins.and.Affinities.of.Fishes 12

Paleoecology.of.Fishes 15

Summary 16

Chapter.3 Aquatic.Environment 17

Aquatic.Ecosystems 17

Properties.of.Water 17

Seawater 21

Fish.in.Water:.Where.Is.the.Gravity? 21

Summary 22

Part III Fish Diversity Chapter.4 Diversity.1:.Chordates.to.Sharks 27

Introduction 27

From.Chordate.to.Vertebrate 27

Agnathans:.Hagfishes.and.Lampreys 28

viii Contents

Conodonts.and.Ostracoderms 31

Early.Gnathostomes 32

Chondrichthyes 34

Summary 37

Chapter 5

Diversity.2:.Teleostomes.to.Bony.Fishes 39

Radiation.of.Teleostomes 39

Acanthodians:.Spiny.Ones 40

Sarcopterygians:.Lobe-Fin.Fishes 40

Coelacanths 41

Lungfishes 42

Actinopterygians:.Ray-Fins 43

Relict.Bony.Fishes 45

Summary 46

Chapter.6 Diversity.3:.Teleosts 49

Diversity.and.Adaptation 49

Lower.Teleosts 50

Bonytongues 50

Eels 51

Herrings,.Sardines,.Menhaden,.and.Anchovies 52

Minnows,.Suckers,.Characins,.and.Catfishes 53

Whitefish,.Arctic.Grayling,.Trout,.Salmon,.and.Pike 54

Cods.and.Anglerfishes 55

Higher.Teleosts 56

Perciformes 56

Flatfishes.and.Tetraodonts 57

Summary 59

Chapter.7 Radiations,.Extinctions,.and.Biodiversity 61

Life.on.Earth.Has.Not.Been.Easy 61

Fish.Extinctions.and.a.Few.Questions 63

Abiotic.Change 63

Biotic.Factors 64

Pseudoextinction 64

Persistence.of.Survivors 65

Enhanced.Radiations 65

Lessons.from.Long-Term.Survivors 65

Ecological.Concepts 66

Case.Study:.Fishes.of.Fossil.Lake 66

Summary 68

ix Contents

Part IV

Freshwater Ecosystems

Chapter.8

Zoogeography.of.Fishes 71

Patterns.and.Species.Diversity 71

Factors.Affecting.Distribution 71

Adaptation 72

Continental.Movement 73

Fishes.of.Zoogeographic.Regions 75

Vicariance.Biogeography 77

Pleistocene.Glaciation 78

The.Future 79

Ecological.Concepts 79

Summary 80

Chapter.9 Lotic.Systems:.Flowing.Water.and.the.Terrestrial.Environment 83

A.Drop.of.Rain 83

Flowing.Water 83

Characteristics.of.Streams 85

Water.Is.(Almost).Always.Moving 85

Channel.Complexity 86

Riparian.and.Floodplain.Features 86

Hydrology 87

Trophic.Status.and.Energy.Transport 88

Ecological.Concepts 89

Summary 91

Chapter.10 Coldwater.Streams 93

Structure.and.Function 93

Coldwater.Fishes 95

Constraints.on.Trout 97

Case.Study:.Greenback.Cutthroat.Trout 100

Summary 102

Chapter.11 Fishes.of.Warmwater.Streams.and.Rivers 103

A.Warmwater.Fish.Viewpoint 103

The.Stream.Connected 103

Stream.Fishes 106

Large.River.Fish.Faunas 108

Case.Study:.The.North.American.Paddlefish 109

Summary 112

x Contents

Chapter.12

Lentic.Systems:.Standing.Water 115

The.Drop.Is.Stored.(Temporarily) 115

Standing.Water.Ecosystems 116

Characteristics.of.Lakes 117

Structure 120

Function 120

Fish.in.Lakes 120

Ecological.Concepts 122

Case.Study:.Lake.Baikal 123

Summary 124

Chapter.13 Fishes.of.Temperate.and.Tropical.Great.Lakes 125

General 125

Fishes.of.Temperate.Lakes 125

The.Laurentian.Great.Lakes:.A.History.of.Change 126

Fishes.of.Tropical.Lakes 133

Case.Study:.Cichlids.of.East.African.Great.Lakes 134

The.Lakes 134

Cichlids 135

The.Nile.Perch.Arrives 136

Summary 139

Chapter.14 Artificial.Lakes.and.Groundwater.Reservoirs 141

Artificial.Lakes:.Reservoirs 141

Structure.and.Function 142

Ecological.Concepts 145

Cumulative.Effects 146

Fish.and.Reservoirs 147

Impoundments 147

Large.Reservoirs 148

Groundwater 149

Case.Study:.Death.Valley.and.Devils.Hole 150

Devils.Hole.Pupfish 151

The.Fight.to.Save.the.Fish 152

Summary 153

Part V Estuarine and Marine Ecosystems Chapter.15 Estuaries.and.Coastal.Zone 157

Coastal.Zone 157

What.Are.Estuaries? 157

xi Contents

Drowned.River.Estuaries 159

Structure 159

Function 160

Estuarine.Fishes 163

Plankton-Based.Systems 166

Oyster.Reefs 166

Ecological.Concepts 167

Case.Study:.Alewives.as.Migrating.Subsystems 168

Background 168

Significance 168

Alewife.Run.at.Mattamuskeet 169

A.Study.of.Alewives 170

Tragedy.Strikes.and.a.Lesson.Learned 172

Summary 173

Chapter.16 Marine.Environments,.Intertidal.Fishes,.and.Sharks 175

Oceanography.and.Marine.Ecology 175

Intertidal.Zone:.Structure.and.Function 179

Beaches 179

Rocky.Shorelines 180

Marine.Fishes 181

Perspectives 181

Diversity.Scrutinized 181

Declining.Abundance 182

Ecological.Concepts 183

Case.Study:.The.Ultimate.Marine.Predator 183

How.Do.Ecologists.View.Sharks? 183

Sharks.as.Human.Predators 184

Humans.as.Shark.Predators 184

Shark.Swimming.as.Multitasking 185

Summary 186

Chapter.17 Neritic.Province.and.Fisheries 189

Inshore.Ocean.in.Perspective 189

Structure 189

Function 190

Pelagic.Systems 190

Benthic.Systems 190

Soft.Substrates 191

Seagrass.Flats 191

Rocky.Substrates 192

Kelp.Forests 192

Coral.Reefs 192

Neritic.Fishes.and.the.Temperate.Zone 194

Marine.Commercial.Fisheries 196

Case.Study:.Cod.and.Northwest.Atlantic.Groundfishery 196

America.or.Codland? 196

xii Contents

New.Technology:.Dragging,.Bycatch.and.Bykill 198

Fisheries.of.the.Grand.Banks 199

Why.Did.the.Fishery.Collapse? 200

Summary 202

Chapter.18 Oceanic.Province.and.Epipelagic.Fishes 203

Province 203

Structure 203

Function 204

Epipelagic.Zone 204

Conditions 204

Fishes 205

Upwellings 208

Case.Study:.Peruvian.Anchoveta 209

Summary 211

Chapter.19 Deep.Sea:.Twilight.to.the.Abyss 213

Features.of.the.Deep.Sea.and.Its.Fishes 213

Structure 214

Function 215

Mesopelagic.Zone 215

Conditions 215

Fishes 216

Abyss 218

Deep.Benthic.and.Benthopelagic 220

Seamounts 221

Fish.Adaptations.in.the.Deep.Sea 222

In.General 222

Bioluminescence 222

Buoyancy 223

Sensory 223

Deepwater.Fisheries 224

Case.Study:.Deep-Sea.Anglerfish 224

Ecological.Concepts 227

Summary 228

Part VI Fish Adaptation Chapter.20 Fitness,.Morphology,.and.Ecophysiology 231

Adaptation.and.Fitness 231

Fish.Morphology.and.Ecophysiology 232

Integrated.Fish.Response 232

Locomotion,.Shape,.and.Function 233

xiii Contents

Physicochemical.Adaptation.with.Organs 235

Dealing.with.Temperature:.Warm.Muscle 235

Obtaining.Oxygen.from.Water.and.Air 237

Buoyancy.and.the.Swim.Bladder 238

Osmoregulation 239

Morphology.and.Sensory.Systems 240

Feeding.Morphology 240

Body.Shape 241

Mouth 241

Teeth 242

Gill.Rakers 242

Gut 242

Sensory.Systems 242

Vision 243

Hearing 243

Chemosensory 243

Mechanoreception 244

Electricity 244

Magnetism 244

Summary 244

Chapter.21 Energy,.Metabolism,.and.Growth 247

Energy.Budgets 247

Fish.Energetics 251

Metabolism 252

In.Perspective 252

Energy.Source.and.Quality 252

Metabolic.Output.and.Rate 253

Growth.and.Aging 254

Metabolic.Stress 257

Stress.in.Fishes 258

Case.Study:.Measuring.Growth.and.Age.in.Hard.Tissues 258

Summary 260

Chapter.22 Adaptation,.Niche,.and.Species.Interactions 263

Adaptation 263

The.Niche 265

Niche.Overlap.and.Response 268

Species.Interactions 269

Intraspecific.Competition 269

Interspecific.Interactions 270

Summary 273

Chapter.23 Populations,.Growth,.and.Regulation 275

Fish.Populations.in.General 275

Present.Status.of.Fish.Populations 275

xiv Contents

Population.Characteristics 276

Population.Growth 278

Population.Regulation 280

Equilibrium/Nonequilibrium 283

Nonequilibrium.(Density.Independence) 283

Equilibrium.(Density.Dependence) 283

Complexity.of.Regulation 284

Carrying.Capacity.Problem 284

Commercial.Exploitation 285

Overfishing 285

Fallacy.of.Maximum.Sustained.Yield 286

Fishery-Induced.Depensation 287

A.Look.at.Fisheries.Yield.Models 287

Summary 288

Chapter.24 Instinct,.Learning,.and.Social.Behavior 289

Why.the.Interest.in.Behavior? 289

Instinctive.Behavior.and.Innate.Mechanisms 289

Orientation 290

Kineses,.Reflexes,.and.Taxes 290

Biological.Clock.(Biorhythms) 291

Cognition.and.Learning 292

Nonreproductive.Social.Behavior 293

Communication 293

Spacing.Behavior 294

Multispecies.Groups 295

Cooperation 296

Machiavellian.Intelligence 296

How.to.Study.Behavior 297

Case.Study:.Behavioral.Interactions 298

Summary 301

Chapter.25 Trophic.Concept.and.Feeding 303

Trophic.Concept 303

Trophic.Cascade 304

Effect:.Bottom-Up.and.Top-Down 304

Fishery-Induced.Trophic.Cascades 305

Feeding.Adaptations 306

Trophic.Categories 306

Detritivores 306

Scavengers 307

Herbivores 307

Omnivores 308

Carnivores 309

Resource.Sharing.and.Trophic.Adaptability 311

Food.and.Selectivity 312

xv Contents

Foraging.Behavior.and.Theory 313

Optimal.Foraging 313

Predatory.Behavior.and.Prey.Response 314

Prey.Defense 315

Basic.Prey.Model 316

Patch.Model 316

Case.Study:.Prey.Response—A.Matter.of.Humps? 318

Summary 321

Chapter.26 Reproductive.Ecology.and.Life.History.Patterns 323

Reproductive.Process 323

Life.History.Patterns 324

Timing.of.Reproduction.and.Environmental.Cues 324

Sex.and.Mating 325

Sexual.Selection 326

Alternative.Breeding.Tactics 326

Spawning.Site.Selection 327

Parental.Care.of.Eggs.and.Young 327

Reproductive.Effort.and.Energy.Allocation 327

To.the.Young 327

To.the.Reproductive.Adults 329

Two.Life.History.Strategies 330

Semelparity 330

Iteroparity 330

Reproductive.Tradeoffs:.r.and.K.Selection.and.a.3-D.Continuum 331

Case.Study:.Timing.of.Spawning 332

Summary 334

Chapter.27 Migration 335

Fish.Move,.Disperse,.and.Migrate 335

Finding.the.Way.Back—Homing 336

Home.Stream.Concept 336

A.Few.Terms 337

Orientation.Mechanisms 338

Spawning.Migrations 340

Oceanodromy 340

Diadromy 340

Potamodromy 341

Examples.and.Descriptions 341

Anadromous.Migrations.and.Homing.of.Pacific.Salmon 341

Catadromous.Migrations.of.Anguillid.Eels 343

Oceanadromous.Migrations.of.Atlantic.Herring 344

Potamodromous.Migrations 346

Case.Study:.Migration.of.Colorado.Pikeminnow 346

Summary 350

xvi Contents

Chapter.28

Larval.Fish 353

Introduction.and.Importance 353

Reproduction.and.Early.Life 355

Description.and.Taxonomy 356

Larval.Ontogeny 357

Larval.Fish.Ecology 359

Ecological.Interactions 359

Habitat.Selection 359

Feeding 360

Predation 361

Why.Larvae? 363

The.Niche.Revisited 365

Fisheries.Ecology.and.Recruitment.Concepts 366

Historic.Concepts 366

Recent.Concepts 367

Marine.versus.Freshwater.Environments 370

Case.Study—Larval.Fish.Movement 370

Summary 373

Part VII Applied Ecology: The Human Factor Chapter.29 Exploitation.and.Fisheries.Management 377

Introduction 377

Historic.Perspective 378

Exploitation 378

Natural.Resource.Conservation 381

Management.Practices 382

In.General 382

Fisheries 383

Regulation 383

Habitat.Management 384

Manipulation.of.Organisms 384

Fisheries:.Practices.and.Problems 384

A.Scientific.Approach 384

Freshwater.Fisheries 385

Estuarine.Fisheries 388

Marine.Coastal.Fisheries 388

Offshore.Marine.Fisheries 389

Concepts.of.Sustainability 391

Ecosystem.Approach 392

Case.Study:.Fish.Salvage.at.Tracy 394

Operation.and.Change 394

Demands.on.Operation 398

Endangered.Species.Acts 398

Invasion.of.Nonnative.Species 398

Smart.Predaceous.Fish 398

xvii Contents

Increasing.Demand.for.Pumping.Water 398

Entrainment.of.Early.Life.Stages 399

Predation.at.Release.Sites 399

Stress 399

Future.of.the.Facility 399

Summary 399

Chapter.30 Conservation.of.Fishes.I:.Crisis.and.a.Response 401

Introduction 401

Biodiversity 401

Biodiversity.Crisis 402

Why.and.How.Are.Species.Going.Extinct? 406

How.Many.Fish.Do.We.Need? 409

Species.Problem 410

A.Response:.The.New.Conservation 411

Endangered.Fish.Recovery? 412

Case.Study:.Can.Science.Save.the.Salmon? 413

Declining.Pacific.Salmon 413

Four.“H”s 415

Harvest 415

Hatcheries 416

Habitat 417

Hydropower 419

Breaching.the.Lower.Snake.River.Dams 419

Can.Science.Save.the.Salmon? 421

Summary 421

Chapter.31 Conservation.of.Fishes.II:.Understanding.the.Decline 423

Five.Causes 423

Physical.Habitat.Alteration 424

Effects 424

Lakes 424

Streams 425

Estuaries 425

Marine.Systems 426

Issues 426

Introduced.Species 429

Effects 429

Lakes 429

Streams 429

Estuaries 430

Marine.Systems 430

Issues 431

Overfishing 434

Effects 434

Lakes,.Ponds,.and.Springs 434

Rivers.and.Streams 435

xviii Contents

Estuaries 435

Marine.Systems 435

Issues 435

Hybridization 436

Effects 436

Lakes 436

Rivers.and.Streams 436

Estuarine.and.Marine.Systems 437

Issues 437

Water.Pollution 438

Effects 438

Lakes 438

Rivers.and.Streams 438

Estuaries 439

Marine.Systems 439

Issues 439

Are.All.Suspects.Guilty? 441

Case.Study:.Chesapeake.Bay—An.Ecological.Disaster 441

Background 441

Oyster.Reefs 442

Loss.of.Planktivores 444

Ecological.Disaster 444

Summary 446

Chapter.32 Changes.and.the.Future 447

Introduction 447

Interesting.Times 447

Global.Climate 449

Changes.in.Progress 449

Warming/Cooling:.Evidence.and.Tipping.Points 452

GCC:.Effects.on.Fish.and.Habitat 454

Direct.and.Indirect.Effects 454

Ecology.and.Fish.Production 454

Invasive.Species 456

Fish.and.Fisheries.in.the.Future:.Bad.News.and.Good.Prospects 457

Welcome.to.the.Twenty-First.Century 459

Summary 460

Appendix 463

Introduction 463

Instructions 464

Agnathans 465

Gnathostomes.(Jaws.in.the.Mouth) 466

Lower.Teleosts 468

Higher.Teleosts 471

Glossary 475

Literature.Cited 483

Preface

ply.adequate.food.for.an.increasing.human.population.(e.g.,.Daniel.and.Minot.1954) But.this.was.not.to.be.true Instead,.major.marine.fisheries.have.collapsed,.and.there.are.worldwide.declines.in.freshwater.fish.populations Where.impacts.have.been.due.to.overfishing.without.major.physical.habitat.destruction,.recovery.has.been.possible Where.habitat.destruction.also.has.occurred,.short-term.recovery.has.been.lacking

My.ichthyology.and.fishery.science.professors.assured.their.classes.that.ocean.fisheries.would.sup-The.cause.of.freshwater.fish.declines.and.losses.is.no.mystery It.is.primarily.due.to.the.effects.of.an.ever-increasing.human.population.on.fragile.and.isolated.systems These.effects.have.reduced.the.distribution.and.abundance.of.fish.populations.by.widespread.changes.that.happen.too.rapidly.for.natural.selection.to.respond

How.pervasive.are.continuing.anthropogenic.effects.on.the.environment?.Some,.if.not.most,.climatologists.believe.that.human.interference.has.so.altered.planetary.function.that.the.relatively.stable.period.that.began.after.the.last.ice.age.(i.e.,.Holocene).has.ended A.new.era.of.climate.change.is.in.progress,.and.it.has.been.named.the.Anthropocene,.a.term.attributed.to.Dutch.scientist.Paul.Cruzen.(Pearce.2007) Disturbed.by.the.lack.of.success.of.endangered.fish.recovery.programs,.I.wondered.how.we.could.better.prepare.for.additional.perturbation I.decided.that.better.education.across.disciplines.was.needed

The concept of this book took shape after I joined the research faculty at the University of.Colorado,.where.I.developed.and.taught.an.ecology.of.fishes.course.for.the.Department.of.Ecology.and Evolutionary Biology The class also was heavily supported by environmental sciences stu-dents This.book.is.based.on.that.course.and.on.student.input It.has.a.functional.approach.with.an.applied.orientation.to.promote.better.understanding.and.use.of.ecological.concepts Case.studies.are.used.as.lessons.in.reality Also,.by.student.request,.I.have.worked.to.make.the.book.more.interest-ing by.including.personal.anecdotes.and.experiences

There.is.a.need.for.more.applied.ecologists.in.fishery.management.and.conservation,.and.better.training.is.needed.to.infuse.management.with.practical.application.of.ecological.theory The.mes-sage:.There.are.few.(perhaps.no).“natural”.ecosystems.remaining,.nongame.fishes.are.in.decline,.invasive.species.are.rampant,.endangered.fishes.are.not.being.recovered,.human.impacts.continue,.and.solutions.are.difficult The.prognosis:.Not.good Fishery.scientists.and.managers.must.become.more.effective.at.understanding.and.dealing.with.resource.issues If.not,.fish.species,.communities,.and.entire.ecosystems.will.continue.to.decline.as.habitats.change.and.species.are.lost I.hope.this.book.will.help

Acknowledgments

This.book.is.a.product.of.15.years.of.experience.in.teaching.the.Ecology.of.Fishes.class.(EBIO.4460/5460).at.the.University.of.Colorado.at.Boulder,.and.I.thank.the.faculty.at.the.Department.of.Ecology.and.Evolutionary.Biology.for.giving.me.the.opportunity I.also.acknowledge.the.aid.provided.by.the.Center.for.Limnology,.Cooperative.Institute.for.Environmental.Sciences.(CIRES),.which provided me with assistance, encouragement, and additional resources My efforts were.greatly.aided.by.the.many.excellent.texts.cited.herein.and.by.undergraduate.and.graduate.research.activities.at.the.University.of.Colorado.and.the.University.of.Denver I.use.the.American.Fisheries.Society’s.Committee.on.Names.of.Fishes.(Nelson.et.al 2004).as.the.authority.for.names.of.fishes.and.Nelson.(2006).as.the.authority.for.phylogenetic.systematics I.am.grateful.for.the.use.of.images.provided.by.Jon.Miller.and.J H McCutchan,.Jr.,.illustrations.provided.in.U.S Government.publica-tions,.and.permission.to.use.copyrighted.material.from.the.American.Fisheries.Society.and.other.publishers In.addition,.J H McCutchan,.Jr assisted.with.photography.and.computer.applications Many.of.the.examples.and.case.studies.I.use.in.this.book.were.obtained.during.my.association.with.North.Carolina.State.University,.the.Army.Corps.of.Engineers,.the.U.S Fish.and.Wildlife.Service,.and.the.University.of.Colorado I.am.indebted.to.reviewers.who.provided.their.encouragement.and.suggestions for improving various portions of the draft manuscript: W R Courtenay, Jr., E.  A Frimpong,.L A Hawkins,.J F Kitchell,.W M Lewis.Jr.,.J H McCutchan.Jr.,.J Miller,.N J Nikirk,.D E Portz,.W. M Robinson,.C L Roehm,.J F Saunders.III,.D E Snyder,.and.the.Ecology.of.Fishes.class.of.2009

Use and Features of the Book

riculum, as an aquatic option in an environmental science program, or as an ecology text in a.fisheries school It.is.intended.for.an.upper.division.undergraduate.course,.but.it.also.can.be.used

This.book.can.be.used.as.a.“stand-alone”.first.course.in.fishes,.as.enrichment.to.an.ecology.cur-at the graduate level, especially with additional assignments The book will supply more than.enough.material.for.an.entire.semester Outside.the.classroom,.I.hope.that.the.book.will.be.useful.as.a.refresher.for.professionals.in.government.and.private.agencies,.consulting.firms,.and.academic.institutions I.also.hope.that.environmental.lawyers,.politicians,.and.inquisitive.hobbyists.will.find.helpful.information.in.it

As.a.class,.Ecology.and.Conservation.of.Fishes.has.attracted.a.mix.of.undergraduate,.graduate,.and.extension.students.whose.interests.and.concerns.are.diverse.(ranging.from.journalism,.econom-ics,.psychology,.and.law.to.diving,.fishing,.aquaria,.environmental.and.fisheries.sciences,.biology,.ecology,.and.ichthyology) If.used.as.a.first.course.in.fishes,.course.prerequisites.should.be.general,.and.the.approach.must.be.broad In.this.case,.the.three.chapters.on.fish.diversity.will.be.needed On.the.other.hand,.if.used.in.a.fisheries.science.program,.the.book.can.be.used.as.a.companion.course.with.ichthyology,.and.the.fish.diversity.chapters.can.be.assigned.only.as.a.review

It is a daunting task to consider the factors that influence the distribution and abundance of.fishes.in.this.rapidly.changing.world In.making.the.effort.to.do.precisely.this,.I.have.provided.real.case.studies.of.fishes.in.all.of.the.major.aquatic.systems These.can.be.updated.as.new.information.is.obtained Some.of.these.case.studies.are.“ecological.disasters.of.varying.types.”.However,.I.believe.the.examples.chosen.are.truly.representative.of.the.current.state.of.such.systems,.and.all.of.them.can.provide.valuable.lessons At.the.end.of.each.chapter,.there.is.a.short.summary.of.the.major.conclu-sions The.summary.and.case.studies.are.provided.to.reinforce.major.concepts

Three chapters are provided to acquaint students with the names and adaptations of major.fish groups.and.some.high-profile.fishes However,.some.students.may.not.have.a.good.grasp.of.the.morphology.of.the.fishes.or.characteristics.of.fish.groups To.overcome.these.difficulties,.a.fish.identification supplement is included in the appendix The supplement can be assigned, covered.in.a.lecture.with.demonstration.specimens,.or.used.as.a.special.laboratory.exercise Identification.of.fishes.and.fish.assemblages.is.aided.by.black.and.white.pictures.in.the.text.and.a.16-page.insert.that.contains.full.color.plates Teaching.videos.such.as.“Eyewitness:.Fish”.and.trips.to.an.aquarium.are.very.useful.teaching.aids,.as.are.online.assignments Videos.referenced.at.the.end.of.selected.chapters.are.enjoyable.and.extremely.helpful.in.understanding.the.systems.and.fishes.concerned.Most.students.are.unfamiliar.with.Greek.and.Latin.terms Thus,.there.is.a.lexicon.of.Greek.and.Latin.words.provided.to.help.them Also,.a.glossary.will.aid.students.with.troublesome.terms.and.concepts

The.student.also.will.benefit.from.applying.theoretical.concepts.to.real-world.situations An

sized References.to.pertinent.reviews.and.specific.papers.should.help.students.who.wish.to.pursue.topics.more.deeply

Author Biography

Harold.M Tyus.is.Emeritus.Research.Scientist.at.the.Center.for.Limnology,.Cooperative.Institute.for.Research.in.Environmental.Sciences,.University.of.Colorado.at.Boulder,.where.he.taught.Ecology.of.Fishes.in.the.Department.of.Ecology.and.Evolutionary.Biology He.is.also.adjunct.professor.of.envi-ronmental.policy.and.management.at.the.University.of.Denver,.where.he.teaches.and.serves.as.a.faculty.advisor Dr Tyus.received.his.academic.training.in.the.Department.of.Zoology.at.North.Carolina.State.University,.with the aid of a National Science Foundation fellowship and a scholar-ship.from.the.National.Wildlife.Federation He.was.also.affiliated.with.the.North Carolina Cooperative Fishery Unit, earning an MS studying sun-fish phylogenetics and a PhD studying population dynamics and migra-tions.of.river.herring His.minor.concentration.was.in.water.resources.management Dr Tyus.is.a.retired.researcher.and.manager.for.the.U.S Government,.serving.23.years.with.the.Army.Corps.of.Engineers.and.Fish.and.Wildlife.Service During.that.time,.he.was.involved.with.environmen-tal.impact.assessment.and.studied.a.wide.variety.of.aquatic.habitats,.fishes,.and.human-induced.changes.in.waters.of.the.United.States,.from.east.coast.oceans,.estuaries,.and.wetlands.to.southwest-ern.desert.rivers He.has.written.and.edited.numerous.scientific.papers.on.fishes.and.government.documents.on.fish.ecology.and.conservation,.including.listing.and.recovery.plans.for.endangered.species He.was.a.member.of.the.Colorado.River.Fishes.Recovery.Team.for.12.years,.and.he.has.been.a.consultant.and.science.advisor.for.industry.and.government His.professional.affiliations.include.the.Desert.Fishes.Council,.the.American.Society.of.Ichthyologists.and.Herpetologists,.and.the.Society.for.Conservation.Biology He.is.a.Fellow.of.the.American.Institute.of.Fishery.Research.Biologists and a Life Member of the American Fisheries Society, which has certified him as a.Fishery.Scientist.and.Fisheries.Professional

sclera.=.hardsom.=.bodyspatula.=.spoonsquam.=.scalesten.=.narrowstom.=.mouthsuper.=.abovesym.=.togethertele.=.perfect,.entiretetr.=.four

tri.=.threetrich.=.a.hairtroph.=.foodura.=.tailvass.=.a.vesselvelum.=.a.coverventr.=.bellyviv.=.livexiph.=.swordzoo.=.animal

A Lexicon of Greek and Latin Word Roots Used in this Text

(Terms.are.abridged.from.Borror.1960.and.Moore.and.Moore.1997)

PART I Introduction

a.home.or.a.place.to.live Assuming.that.some.organism(s).live.in.this.place,.a.literal.translation.of

life.in.all.of.its.places.would.be.an.enormous.field.of.study,.so.ecology.is.a.broad.field.with.many.subdivisions For.example,.“life”.can.include.one.organism.or.various.taxa,.including.species.or.populations The.“home”.or.“place”.can.be.terrestrial.or.aquatic,.or.even.finer.divisions.such.as.ecosystems.and.habitats Also,.we.might.study.the.adaptations.of.organisms.to.their.environment,.as.reflected.in.physiology,.behavior,.feeding,.reproduction,.and.so.on Another.subdivision.might.consider.the.role.of.environmental.conditions.in.shaping.adaptation.as.reflected.in.the.fossil.record Finally,.a.branch.of.ecology.is.devoted.to.sorting.out.the.role.of.humans.on.the.physical.(nonliving.or.abiotic).and.living.(biotic).components.of.the.environment

tion.of.nature”.(Odum.1971),.but.most.biologists.would.probably.define.ecology.as.the.study.of.“the.interrelationships.between.organisms.and.their.environment.and.each.other”.(Lawrence.1989) But.there.are.many.subdivisions.of.ecology,.and.other.definitions.have.been.provided.to.more.closely.represent.them Krebs.(1972).identified.the.basic.ecological.problem.as.the.determination.of.“the.causes.of.the.distribution.and.abundance.of.organisms.”.Obviously,.the.causes.include.abiotic.and.biotic.environmental.factors.and.the.capacity.or.adaptations.of.the.organism.to.respond.to.those.factors

In.a.general.or.fundamental.sense,.ecology.may.be.defined.as.“the.study.of.structure.and.func-Ecology can have a descriptive or a functional approach A descriptive approach seeks to.describe.an.ecosystem.from.producers.through.decomposers,.investigating.the.interrelationships.between.its.components A.functional.approach.is.more.focused,.addressing.specific.relationships.and.general.problems Ecology.also.can.be.taught.from.a.theoretical.and.an.applied.standpoint Hypotheses, theories, and models have been developed to explain various phenomena observed.in.the.science.of.ecology Some.theoretical.concepts.have.never.been.fully.accepted.in.a.working.sense,.but.almost.all.can.serve.in.providing.a.basis.for.understanding Such.concepts.also.are.useful.in.the.field.of.applied.ecology.as.a.basis.for.resource.management,.conservation,.and.preservation.As.human.populations.increased,.their.effects.on.natural.systems.have.had.far-reaching.impacts.on.ecosystems,.and.new.fields.have.emerged.in.ecology.to.address.these.impacts Classified.collec-

tively.as.applied ecology,.these.fields.include.environmental.science,.conservation.biology,.landscape.

ecology,.restoration.ecology,.and.ecosystem.management Thus,.applied.ecology.considers.the.affect.of.humans.on.every.aspect.of.the.natural.world.(e.g.,.Hinckley.1976) Recent.developments.in.rapidly

4 eCoLoGY AnD ConseRVAtIon oF FIsHes

emerging areas of applied ecology were effectively encapsulated by Smith and Smith (2001) and.Krebs.(2008)

FISh eCOLOGY eXPLOReD

What.then.is.the.scope.of.ecology.of.fishes?.I.prefer.to.define.it.as.the.study.of.those.factors.that.influence.the.distribution.and.abundance.of.fishes In.this.sense,.factors.are.abiotic.and.biotic.components.of.the.environment,.those.conditions.that.Darwin.and.Horan.(1979).associated.with.the.struggle.for.existence Clearly,.ecology.of.fishes.is.a.study.of.aquatic.ecosystems,.fish.adaptation,.natural.selection,.and.fitness

Many.papers.dealing.with.various.aspects.of.fish.ecology.in.the.United.States.were.published.after the turn of the twentieth century, but more complete treatments of the subject have been.published only recently Early on, regional, state, and local guides to fishes, fishing, and fisher-ies.included.much.descriptive.information.on.fish.ecology,.but.texts.more.concerned.with.general.aspects.of.fish.ecology.were.marketed.in.natural.history.or.fishery.management.fields Descriptive.and.functional.information.on.fish.ecology.also.appeared.in.fish.biology.(Kyle.1926;.Lagler.1952;.Bond.1979).and.ichthyology.texts.(e.g.,.Lagler.et.al 1962;.Moyle.and.Cech.1982) However,.it.was.not.until.the.latter.part.of.the.century.that.texts.providing.more.experimental.approaches.appeared.(e.g.,.Bone.and.Marshall.1982;.Wootton.1990;.Jobling.1995;.Diana.1995)

Ecology texts are written with different purposes, goals, and perspectives The Ecology of

focus.of.that.book.was.to.explore.concepts.of.ecology,.with.the.goal.of.developing.“the.biological.basis.of.a.rational.fishery.”.Its.purpose.was.to.aid.human.exploitation,.ostensibly.according.to.eco-logical.principles Other.authors.also.have.focused.on.the.ecology.of.exploited.fish.populations.(e.g.,.Pitcher.and.Hart.1982),.but.developing.“rational”.fisheries.(i.e.,.sustainable.fisheries.constructed.on.a.scientific.basis).has.been.elusive,.and.recent.texts.have.been.oriented.more.toward.understanding.fundamental.ecological.problems.(Jennings.et.al 2001)

In simple terms, the basic scope of fish ecology considers use of space (i.e., habitat) by the.fish.and.how.the.fish.obtains.and.uses.energy.to.maximize.fitness There.are.two.components.to.this:.what.constraints.are.imposed.on.the.fish.by.the.environment.and.how.the.fish.responds.with.adaptation

There.are.at.least.two.overlapping.areas.of.study.reflected.in.this.text:.ichthyology.and.ecology The.study.of.fish,.ichthyology,.is.an.academic.approach.that.includes.fish.systematics,.anatomy,.physiology,.evolution,.and.ecology As.taught.in.most.institutions.today,.its.focus.is.fish.taxonomy.and.phylogenetic.systematics An.old.science,.by.the.time.Linnaeus.began.his.taxonomic.work,.a.fish.classification.system.had.already.been.developed

As.previously.indicated,.ecology.is.a.broad.field,.combining.many.disciplines.and.approached.with.different.perspectives I.have.organized.this.text.into.an.introduction.and.six.additional.parts.that cover the ecology of fishes: evolutionary ecology, fish diversity, freshwater, estuarine and.marine.ecosystems,.adaptation,.and.applied.ecology

Anthropogenic change has resulted in a loss of fish habitat and diversity across the planet;

and.a.new.synthetic.field.of.study,.conservation biology,.has.emerged.in.response Conservation.

biology.represents.a.specific.discipline.in.the.conservation.movement.that.stresses.scientific.rigor,.multidisciplinary.approaches,.and.innovative.measures.to.address.the.biodiversity.crisis Meffe.et.al (1997).provided.three.guiding.principles.of.conservation.biology.that.are.paraphrased.here:.(1).evolutionary.change:.evolution.is.the.basic.axiom.that.unites.all.of.biology;.(2).dynamic.ecology:.the.ecological.world.is.dynamic.and.characterized.by.nonequilibrium;.and.(3).the.human.presence:.humans.must.be.included.in.conservation.planning Adherence.to.these.principles.was.a.priority.in

writing.Ecology and Conservation of Fishes.

5 eCoLoGY oF FIsHes: Content AnD sCope

WhAT IS A FISh?

The.worldwide.fish.fauna.includes.a.broad.diversity.of.organisms.with.various.combinations.of.shared.and.new.characters Popular.notions.of.the.fish.have.been.conveniently.summed.up.by.a

• Alive without breath—This.refers.to.breathing.air.directly.for.respiration The.belief.is.that.fish.take in.oxygen.from.the.water.and.not.from.air However,.some.fishes.have.perfectly.good.lungs,.and many.fishes.have.an.open.swim.bladder.that.can.be.used.to.extract.oxygen.from.air Other.fishes have.dispensed.with.lungs.entirely.and.have.more.recently.derived.organs.that.allow.oxygen.to.be taken.directly.from.the.atmosphere.

• As cold as death—It.is.true.that.most.fishes.are.about.the.same.temperature.as.the.water.in.which they.live,.and.their.temperature.would.approximate.that.of.a.corpse However,.some.fishes.(such.as sharks.and.tunas).regulate.their.internal.body.temperature.by.taking.advantage.of.heat.produced by.sustained.swimming:.incoming.blood.from.the.gills.is.warmed.by.passive.heat.transfer.from outgoing.blood.

• Never thirsty, ever drinking—Marine.fishes.live.in.seawater,.which.is.a.medium.of.high.salt.content compared.with.their.blood They.have.to.drink.seawater.to.replace.water.that.is.passively.lost.to.the salty.medium,.and.then.excrete.concentrated.salt.back.again.using.special.organs However,.fresh- water.fish.have.just.the.opposite.problem The.do.not.“drink”.regularly.

• All in mail, never clinking—This.one.is.easy Mail.is.a.type.or.armor.made.by.interlocking.small chains.together.like.fish.scales The.analogy.would.apply.to.fishes.that.have.bony.ridge.scales Sorry, but.many.fishes.(e.g.,.catfish).do.not.have.scales.

Let.us.not.be.too.harsh.on.Tolkien His.intentions.were.to.be.entertaining,.not.scientific,.but.truly,

what.is.a.fish?

As.pointed.out.by.Nelson.(2006),.some.authorities.would.restrict.fish.to.only.include.jawed.bony.fishes,.some.authorities.have.added.sharks.and.their.close.relatives,.and.some.would.also.include.jawless.hagfishes.and.lampreys However,.if.the.term.is.restricted.to.a.monophyletic.group,.then.only.the.recent.ray-finned.fishes.would.be.acceptable.as.fish

In.a.general.sense.and.in.recognition.of.the.great.diversity.of.fishes,.I.endorse.Nelson’s.(2006).simplified,.if.artificial,.definition.of.fishes.as.“aquatic.vertebrates.that.have.gills.throughout.life.and.limbs,.if.any,.shaped.like.fins.”.This.is.a.simple.but.workable.concept The.definition.is.artificial

How.do.we.recognize.a.fish?.Draw.two.curved.lines.(one.curved.down.and.the.other.curved.up).allow.them.to.meet.at.one.end.but.overlap.on.the.other.and.then.ask.anyone,.“What.is.it?” They.will recognize a fish instantly Almost all extant fishes are streamlined, with a torpedo-shaped

6 eCoLoGY AnD ConseRVAtIon oF FIsHes

appearance because of the need for locomotion in water, which is an extremely dense medium.compared.to.air Of.course,.we.add.a.few.fins.and.scales.and.then.we.have.something.like.a.recently.evolved.fish However,.there.are.subtle.differences.that.we.will.learn.to.appreciate,.such.as.those.shown in Figure 1.1, which displays prominent features of fish morphology in a minnow and a.largemouth.bass

Having.made.the.point.about.streamlining,.it.must.be.immediately.followed.by.the.knowledge.that.many.fish.are.not.streamlined.for.fast.swimming.because.they.have.no.need.for.it Benthic.fishes.that.hide.on.the.bottom.and.ambush.their.prey.are.dorsoventrally.flattened.like.a.pancake Fishes.that.hunt.and.have.need.of.escape.in.weedy.ponds.are.likely.to.be.short.and.laterally.flattened.for.quick.turns Fishes.that.hunt.in.water.with.structures,.such.as.kelp.forest.or.sargassam.weed,.are.likely.to.be.camouflaged.as.part.of.the.surroundings.for.protection.and.ambush

Where.do.fish.occur?.An.almost.satisfactory.answer.is.wherever.there.is.liquid.water.and.there.is.access Fishes.occur.from.the.Arctic.Circle.to.the.equator,.and.from.high.mountains.to.the.ocean.abyss They.occur.in.freshwater,.in.salt.water,.in.surface.water,.in.ground.water,.and.sometimes.in.no.water.at.all!

Finally,.there.are.the.inevitable.questions:.What.is.the.largest.or.the.smallest.fish?.The.largest

fish.is.the.whale.shark.(Rhincodon typus;.Figure.1.2),.with.a.length.of.at.least.18.3.m.(60.ft).(Robins.

and.Ray.1986),.with.the.basking.shark.(13.7.m).in.second.place Choosing.the.smallest.fish.is.a.little.more.difficult.because.smaller.fishes.seem.to.be.popping.up.in.different.taxa I.give.the.smallest

Figure 1.1 Largemouth bass Micropterus salmoides (a), a higher teleost, and golden shiner Notemi­

gonus  crysoleucas (b), a lower teleost (Courtesy of Raver, D and the U.s Fish and Wildlife

service (UsFWs), national Conservation training Center (nCtC).)

Figure 1.2 Largest extant fish, the whale shark R typus, shown with diver for size comparison (Courtesy of

Cada, R n., fishbase.org, www.fishbase.org Image from Wikimedia Commons at http://commons wikimedia.org/wiki/File:Rhtyp_u0_white_bg.gif.)

7 eCoLoGY oF FIsHes: Content AnD sCope

FISh: The FIRST VeRTeBRATe

Humans.inherited.most.of.their.morphology.from.fishes,.including.almost.all.of.their.internal.organs The.first.fishes.were.chordates.and.shared.some.very.important.features.of.chordate.ances-tors But.the.first.fish,.our.first.recognizable.ancestor,.was.different It.was.remarkable.and.it.has.been.considered.a.radical,.even.a.reckless.experiment.of.nature.(Curtis.1949) What.made.this.organism.so.different?.In.a.layman's.sense,.compared.with.the.arthropods.(the.main.thrust.of.animal.evolution.if.we.consider.the.number.of.species.prevalent.today),.it.was.outside.in,.downside.up,.and.backward!.Nonscientists.in.general.are.apparently.so.unaware.of.differences.between.vertebrates.and.arthro-pods,.that.the.gut.of.the.shrimp.exposed.on.the.back.of.the.tail.when.shell.is.removed.is.named.its

course.is.on.the.outside,.and.apparently.no-one.seems.to.miss.the.backbone.when.using.the.tool.Vertebrates.first.appeared.with.the.origin.of.fishes Thus,.an.understanding.of.fish.evolution.is.fundamental.for.understanding.origins.of.tetrapods,.that.is,.amphibians,.reptiles,.birds,.and.mam-mals However,.the.evolution.of.tetrapods.was.arguably.a.very.small.step.for.fishes.at.the.time,.con-sidering.the.number.of.extant.fish.species.(three.of.all.five.vertebrates).and.enormous.fish.diversity.represented.by.more.than.400.million.years.of.evolution After.all,.only.one.species.of.tetrapod.poses.a.significant.threat.to.them Also,.it.is.important.to.note.that.extant.fishes.are.just.as.modern.as.the.most.recently.derived.vertebrate.although.they.represent.an.ancient.lineage

SUMMARY

standing.and.exploiting.natural.resources Ecology.is.a.broad.field,.with.many.subdivisions.of.study.that.focus.on.organisms,.environments,.adaptations,.behavior,.evolution,.and.anthropogenic.effects.(applied.ecology) In.this.text,.we.study.the.ecology.of.fishes:.the.study.of.those.factors.that.influ-ence the distribution and abundance of fishes By fish, we mean “aquatic vertebrates that have.gills throughout life and limbs, if any, shaped like fins” (Nelson 2006) Fish are adapted for a.life.in.water,.and.most.are.streamlined;.however,.they.can.vary.greatly.according.to.adaptations.mainly.for.feeding.and.reproduction Fish.occur.widely.on.the.planet,.from.high.mountains.to.ocean.abysses Fish.were.the.first.vertebrates,.which.appears.to.be.a.remarkable.experiment.of.nature An.understanding.of.the.evolution.of.fish.is.an.aid.in.understanding.the.rise.of.tetrapods.and.the.great

Ecology.had.its.beginnings.in.natural.history.as.humans.sought.information.to.use.in.under-Figure 1.3 preserved specimen of female ceratid anglerfish P spiniceps, with attached parasitic male

(Courtesy of pietsch, t W.)

8 eCoLoGY AnD ConseRVAtIon oF FIsHes

diversity.supporting.the.evolution.of.fish The.effects.of.humans.on.fish,.fish.populations,.and.their.habitats.have.been.so.pervasive.that.anthropogenic.changes.are.a.main.focus.of.this.book

Recommended teaching aid:.Eyewitness.video:.Fish!.BBC.Lionheart.(1994).

Further reading:.Moyle.1993.

PART II evolutionary ecology of Fishes

Water.is.the.biological.medium It.is.present.in.all.living.organisms.on.Earth Some.organisms.live.in.it,.and.the.rest.of.us.carry.it.around.with.us.in.tissues.or.bottles It.is.a.modifier.of.temperature.and.a.major.determiner.of.climate Only.the.presence.of.water,.the.universal.solvent,.facilitated.the.chemical.reactions.that.were.necessary.for.life.to.develop.and.evolve It.is.the.reason.that.Earth.is.habitable.by.life.as.we.know.it We.will.learn.more.in.the.next.chapter.about.this.amazing.fluid.that.we.generally.take.for.granted For.now.it.is.important.to.point.out.that.evolution.of.the.vertebrates.was.waterborne.for.a.very.long.time

eVOLUTIONARY eCOLOGY

ences.over.time;.in.Darwin's.terms,.“descent.with.modification.”.Ecology.is.the.study.of.interrelation-ships.between.organisms.and.their.environment.(or.as.used.here,.the.study.of.factors.that.influence.the.distribution.and.abundance.of.fishes) By.combining.the.two.disciplines,.evolutionary.ecology.is.the.study.of.interrelationships.(e.g.,.what.and.how.various.factors.have.influenced.the.distribution.and.abundance.of.fishes).over.time To.understand.the.evolution.of.fishes,.it.is.necessary.to.identify.taxa.and.be.able.to.follow.them.through.time,.determine.adaptations.(principally.through.morphology.and.analysis.of.deposits.in.which.they.occurred),.understand.how.environmental.conditions.would.have.affected.the.organism,.and.appreciate.geological.time.scales Central.to.the.issue.is.adaptation.for survival,.for.if.fishes.do.not.survive.they.cannot.reproduce.and.there.would.be.no.evolution.Survival.of.organisms.over.time.is.affected.by.both.intrinsic.and.extrinsic.factors Intrinsic.fac-

Evolution.is.the.development.of.new.types.of.organisms.from.old.ones.by.accumulating.differ-tors.are.within.the.organism;.they.are.predictable.and.therefore.deterministic—a.term.that.means regulative within limits The term homeostasis refers to physiological stability due to negative.

and.positive.feedback This.regulation.also.has.been.likened.to.steady-state.or.fluctuation.within