Cambridge University Press
0521844622 - Ecological Census Techniques - a handbook - by William J. Sutherland
Index

Index

Note: page numbers in italics refer to figures, tables and boxes.


Abney level 377

abundance

   absolute 311

   amphibian data 283

   bird surveys 174–5, 311, 312

     timed species counts 313–14

   change monitoring in invertebrates 214–15

   electrofishing 256

   plants 186–7

     relative 188

   quadrats 191

   random distribution 172

   relative 311, 312

     plants 188

   standardisation of time for observations 174

   underwater observation of fish 254

abundance indices 174

   bird surveys 76, 325

   fish 250

   mammals

     footprint tracking 365

     herbivore-feeding signs 364

     line transects 357

     runways 365

   species frequency 178

accuracy 14

acoustic sampling of amphibian calls 290–1

   scan searching 287

activity

   codes for bird-mapping censuses 317

   mammal

     footprint tracking 365

     runways 365

adaptive management 67–70

adaptive sampling 51–4

   analysis 54

aerial counts

   line transects from air 322–4

   mammals 351–2, 358–9, 366

   seals 366

   tree-nesting bird colonies 334–5

   vegetation mapping 198–200

air, mammal counts 352

Akaike’s information criterion 76–7, 119

   POPAN software 182

alcohol solution 219

   malaise traps 230

alert programmes 78

   alternative hypothesis tests 80

   filters 78–9

   red/amber/green 79–80

   significant 79

alert systems 77–80

algae, benthic 209–10

alligators 300

   tail-scute removal 305

ammonium ions 389

   measurement 391, 394

   water-testing kits 399

ammonium probes 390–1

Amphibian Research and Monitoring Initiative (ARMI) 290

amphibians

   abundance data 283

   aggregations 278

     netting 287

     scan searching 286–7

     trapping 288–9

   artificial cover 288, 289

   breeding activity 278–9

   breeding sites 278

     encircling 285–6

   calling 284, 287

     surveys 290–1

   data collection 293

   decline 279–80, 293

   detection probability 281–4

   drift fencing 285, 285–6

   eggs 278–9, 287, 291

   enclosure sampling 289

   extinction 279–80

   habits 278

   individual-recognition methods 280–1, 282

   infectious diseases 293

   larvae 278–9

   mark–recapture methods 280–1, 291

   multiple-method use 291, 292

   netting 287, 291

     removal studies 290

   patch sampling 289–90

   PIT tags 281, 282

   pitfall traps 285, 285–6, 288

   quadrats 289

   recognition, individual 281

   removal studies 290

   scan searching 286–7

   skin-pattern recognition 280, 282

   spawn strings 287

   toe-clipping 280, 282

   transects 289–90

   trapping 288–9, 291

     removal studies 290

   visual recognition 281

Analysis Browser utility 145

analysis of covariance 161

analysis of variance 62

   multiple, randomised observations 158

   two-way 159–60

anemometers, cup 372

angling see hook and lining, fish

ANOVA 4

aquatic systems, sediment characteristics 399–405

aquatic vegetation mapping 200–1

artificial substrates, invertebrate censusing 220

aspirators, invertebrate capture 220–1

assemblages, change monitoring in invertebrate species 215

assumptions, testing 15–16

augers 399

autoanalysers, continuous-flow 390, 391

   phosphorus-compound measurement 396

auto-titration machines 386

average number estimates, precision 25

Baermann funnel 240

bait traps

   aquatic invertebrates 243

   crocodiles 303–4

   fish 269

baits

   bias 237

   footprint tracking 365

   invertebrate censusing 236–7

   mammal traps 361

   reptiles 303

     crocodiles 303–4

     small lizards 301

bands see ringing

bankside counts for fish 251–3

basking sites, turtles 303

bat detectors 355–6, 360

bats

   call counting 360

   roosts/nurseries 354–6

beam trawl 261

beating, invertebrate censusing 228

Beaufort scale 372, 373

beetles, nocturnal 215

behaviour impact of census methods

   marking 95, 136

   trapping 136

belt transects 197

   plants 196

benthic cores, invertebrate censusing 244–5

Berlese funnel 240

bias

   behavioural impact of marking/trapping 136

   frequency of occurrence 174–5

   handling 16

   mark–recapture studies 125–6

   sampling 20

     unavoidable 23

   sources 15–16

   Wileyto et al. mark–recapture method 132

biomass, plants 187

   harvesting 193–4

   quadrats 190–2, 193–4

biomass estimation of fish 263

   hydroacoustics methods 272

   spawning stock 274–5

bird surveys

   abundance 175, 174–5

     indices 76, 325

   abundance measurement 311

     relative 312

   activity codes for mapping censuses 317

   burrow-nesting 332–3

   capture techniques 328–31

   census method choice 309–11

   cliff-nesting 332

   colony-nesting 331–5

   complete census 309

   design 308–9

   detection probability difference correction 326–8

   distance estimation 319, 320, 321

   distance sampling 319–20, 321, 323

   dropping counts 339–40

   flock counts 336–7

   flocking birds 313

   flush counting 334

   footprints 340

   frequency of occurrence 171–2

   ground-nesting species 333–4

   high bird densities 325

   indirect methods 339–40

   line transects 323, 319–24

   listing methods 311–13

     time-periods 312

   mapping censuses 317

   marking methods 344

   migrant counts 337–8

   mist nets 329, 342

   monitoring 308

   nest counting in colonies 331–5

   number of counts 325–6

   point counts 319, 323, 324–6

     playback of songs/calls 341–2

   population index 308

   population size 308

   radio tracking 344

   reporting rate 311

   response to playback 333, 341–2

     point counts 341

   ringing 329, 330

   roost counts 335–6

   sample 309

   seabirds 322

   synchronous breeding 332

   territory mapping 314–19

     playback of songs/calls 341

     singing 314, 318–19

   timed species counts 313–14

   tracking strips 340

   transects 319–26

     playback of songs/calls 341

   tree-nesting 334–5

   UK indicators 81

   vocal individuality 342–4

   waterfowl 322

   see also calls, bird; songs, bird

black plastic sheets, reptile capture 298

boats, electrofishing 255–6

Bob James Pointy Stick (BJPS) method 400, 401

bootstrapping 32

   adaptive sampling 54

   stratified sampling 51

Bouyoucos method 402, 403

bowl colour, water traps 233

box traps, reptiles 303

branding, reptiles 305

Braun–Blanquet scale 191

   plant quadrats 190

breeding, synchronous in birds 332

Breeding Bird Survey index 84

breeding season

   bird-nest counting in colonies 331–2

   territory mapping 314–15

Buchner funnel, Hartley form 381, 381

buffers, pH measurement 376

bulb types, light traps 234–5

Burnham and Overton method 114–18, 128

burrows

   colonial-bird-nest counting 332–3

   mammal counts 354

     line transects 357

butterfly cone trap 237

calculations 16–18

   precision 17

   terminology 17

calendars 5–6

   with divisions 6–7

calibration

   double sampling 168

   frequency of occurrence 172–3

   indices 165, 163–6, 167

     biologically based 167

calls

   amphibians 284

     scan searching 287

     surveys 290–1

     temperature effects 162

   bat 355–6

   bird

     burrow-nesting species 333

     nocturnal-songbird migrant counts 338

     response to playback 341–2

     singing in territory mapping 314, 318–19

     vocal individuality 342–4

cameras, miniature

   burrow-nesting species 333

   tree-nesting-bird colonies 334

capture

   bird-survey techniques 328–31

   invertebrate censusing 220–1

   probability constant 114–15

   and recapture, continuous 132–3, 134–5

   stress 361

CAPTURE program 103, 108, 115, 118, 129, 140

   closed populations 181–2

   mammal trapping 362

   trapping webs 151–2

capture–mark–recapture methods

   bird surveys 328, 330–1

     burrow-nesting birds 333

     vocal individuality 343

   see also mark–recapture methods

capture–recapture software packages 181–2

   closed populations 181–2

   open populations 182

   see also CAPTURE program; MARK program

carapace, notch cutting in reptiles 305

carding, Lepidoptera preserving 219–20

catchability, mark–recapture studies 100, 103, 108–10

catching without release 91

catch per unit effort (CPUE) 110, 112, 250

   bird surveys 328–30

   fish 263

     electrofishing 256

     gill-net catches 268

     hook-and-line capture 266

     trapping 269

CCA/CANOCO ordination technique 215

chaining method 74

change-in-ratio method 130, 131

chemical abbreviations 385

chemical analysis 390–1

   phosphorus-compound measurement 396

chemocline 405

chlorinity measurement 382

cliffs, colonial-bird-nest counting 332

climate, plant phenological differences 188

clumped distribution 168

cluster sampling 35, 33–5, 36–7

   adaptive 52–4

   costs 34

   designs 39

   population-size estimation 54–7

   precision 34

clustering

   territory mapping 317–18

   variance 30

collecting, invertebrate censusing 216

colonies, bird-nest counting 331–5

colour variation in mammals 359

Common Bird Census index 84

community, science in 68

conductivity measurement 381–2

   conversion to salinity 382

   dissolved-oxygen meters 389

conductivity meter 382

confidence intervals 25–7

confidence limits 14, 32

   calculation 26–7

   cluster sampling 55–7

   random sampling 46–7

   stratified sampling 51

   two-level sampling 44–5

Constant Effort Sites (CES) scheme 328

continuous-flow autoanalysers 390, 391

   phosphorus-compound measurement 396

corers

   benthic invertebrates 244–5

   cylindrical samplers 399–400

correction factors, indices 161

correlation analysis 4

correlation coefficient, Spearman’s rank 96–7

costs

   cluster sampling 34

   multi-level sampling 38

   precision balance 14

   stratification 48

counts

   annual 73

   attempted complete enumeration 91

   catching without release 91

   change-in-ratio method 130

   complete 90–2

     general 90–1

     plotless sampling 91–2

   density estimates 157

   habitat sampling 90–1

   incomplete 90

   mammals, total 351–2

   marking methods 91

   observed 155

   part of population 156–7

   plant 188–9

   removal method 129–30

   repeated at same site 58–62

   sample 94–129

   sampling whole area 136

   see also bird surveys; mark–recapture methods

covariance

   analysis of 161

   spatial-variation-of-numbers modelling 66–7

   spreadsheets 16–17

cover

   artificial for amphibians 288, 289

   plants 186–7

     quadrats 190, 193

     transects 197

     visual estimates 190, 191

Craig and du Feu continuous capture-and-recapture method 132–3, 134–5

crocodiles 300

   tail-scute removal 305

   trapping 303–4

cue counting 157

cylinder samples, invertebrate censusing 242–3

DAFOR (dominant, abundant, frequent, occasional or rare) 189, 196

   aquatic-vegetation mapping 200

damselflies 221

data

   analysis 16–18

   back-transformation 32

   calculations 16–18

   collection 10

   presentation 3–4

   protocol design 4–5

   required detail 8

   requirement 4

   security 8–9

   storage 8–9

   time for collection 5–7

   transformation 30–2

Data Explorer utility 145

data logger 375

data sheets

   creation 8–10, 10

   types 9

DCA/DECORANA ordination technique 215

Declining Amphibian Populations Task Force (DAPTF) 279–80

   Fieldwork Code of Practice 293

density estimation

   counts 157

   distance sampling 141–2, 148

     bird surveys 327

   hydroacoustics methods for fish 272

   line transects 146, 147, 321, 323

     comparison with point transects 148

   phytoplankton 208–9

   plants 186, 187

     quadrats 190, 192

     visual 193

   plotless sampling 92

   point counts 148, 150, 326

   territory mapping 318

   trapping grid 361

   trapping webs 149–50

   T-square sampling 92, 92, 93

   underwater observation of fish 254

   variance 148

   visual 193

density index, timed species counts 178

depth gauges, aquatic vegetation 200

dessication funnels

   bias 240

   invertebrate censusing 239–40

detectability

   bird surveys 327

   estimation 148

   function 73

     gradient 148–9

detection of animals, distance sampling 142

detection probability

   amphibians 281–4

   difference correction in bird surveys 326–8

diet, mammalian herbivore feeding signs 364

digging in invertebrate censusing 238–9

   benthic 244–5

dip nets, aquatic turtle capture 300

discriminant functions 119

displacement sampler 388

disposal procedures, water chemistry 384–5

dissolved-oxygen measurement 386, 385–9

   percentage concentration 389

   water-testing kits 399

distance bands

   line transects 321–2

   point counts 325

distance estimation

   bird surveys 319, 320, 321, 325

   line transects 319, 321

   point counts 325

DISTANCE program 15

   line transects 146

   point transects 148

   trapping webs 151–2

distance sampling 141–52

   analysis 143–5

   ancillary information 145

   bird surveys 319–20, 321, 323

     detectability 327–8

   density estimates 141–2, 148

   detection of animals 142

   field methods 141–3

   line transects 145–6, 319–20, 321, 323

   measurement accuracy 142–3

   mobile animals/stationary observer 146

   passive 148–52

   point transects 148

   principles 141–3

DISTANCE software 144–5

distribution

   normal 30

   not normal 30–2

   two-dimensional 21

   zero counts 32

DNA recovery 136

   amphibian toe-clipping 280

   mammals

     dung 363

     hair 366

   recognition 137

Domin scale 191

   plant quadrats 190

double-observer method 137, 138–9

   detectability in bird surveys 327

   mammal counts 351

   scan searching for amphibians 287

double sampling 168, 169–71

   detectability in bird surveys 327

double-survey method 140

dragonflies, counting along transects 221

drift fencing

   amphibians 285, 285–6

   pitfall traps 285, 285–6, 302–3

   reptiles 302–3

dropping counts

   bird 339–40

   mammals 363–4

     line transects 357

drum nets, reptiles 303

dung piles

   mammal counts 363–4

   mammal line transects 357

D-vac samplers 226

echosounding

   aquatic vegetation 200

   hydroacoustics for fish catching 271–2

edge clusters, territory mapping 318

edge effect

   point transects 148, 149

   sample-unit size 25

   territory mapping 315, 318

eggs

   amphibians 278–9, 291

     scan searching 287

   fish 252

     density 274–5

     emergence traps 275

     plankton nets 274–5

     preservation 274

     visual estimates 273

     volumetric estimates 273–4

Ekman grabs 245

electrodes

   oxygen 386, 389, 406

   pH measurement 376–7

   redox-potential measurement 405

electrofishing 254–7

   advantages 257

   bias 257

   disadvantages 257

   environmental factors 256

   water conductivity 256

emergence traps 238

   fish eggs 275

   invertebrate censusing 237–8

     aquatic 243–4

enclosure sampling, amphibians 289

endoscopes, burrow-nesting species 333

energy-flux measurement 379

enumeration, attempted complete 91

environmental-variable measurement 370–1

   selection 370–1

   technique 371

estimates, reliability 14–16

ethics, reptile studies 306

ethyl acetate fumes 219

ethylene glycol 223

   Malaise traps 230

   water traps 233–4

euphotic zone 380

   estimation 380

eutrophication, nitrogenous compounds 389

evaluation surveys of invertebrates 214

extent of scale 371

extinction, amphibians 279–80

extraction of animals from habitat sample 90–1

extractors, mechanical 91

exuviae counting 221–2

feeding signs, mammalian herbivores 364

field survey monitoring of bats 355

figures 1

   drawing 4

   number required 2

filters 78–9

fish

   abundance indices 250

   bankside counts 251–3

   biomass estimation 263

   capture methods 250–1

   catch removal from nets 258

   catch per unit effort 250, 256, 263

   commercial catch data 250

   eggs 252

     density 274–5

     emergence traps 275

     plankton nets 274–5

     visual estimates 273

     volumetric estimates 273–4

   electric fishing 254–7

     water conductivity 256

   frightening 256

   gill netting 266–9

   habitats 251

   hook and lining 265–6

   hydroacoustics 271–2

   lift netting 263–5

   number estimation 263

   observation methods

     bankside counts 251–3

     bias 254

     underwater 253

   push netting 263–5

   sampling methods 250–1

   seine netting 257–60

   swimbladders 272

   throw netting 263–5

   trapping 269–71

   trawling 260–3

   underwater observation 253

fishing

   hook and lining 265–6

   small lizards 301

fixation, invertebrates 219

flight-interception traps 232

flipper tags, turtles 305

floats 372

flock counts, bird surveys 336–7

   estimation bias 337

flotation, soil cores 239

flow meters 372–4

flush counting of birds 334

fogging, invertebrate censusing 228–9

footprints

   bird surveys 340

   mammal counts 364–5

formaldehyde, fish-egg preservation 274

frequency of occurrence 33, 173, 168–73, 179–80, 181

   bias 174–5

   calibration 172–3

   correction 176

   estimate of true frequency 180–1

   habitats 175

   methodology 174–6

   plants 186, 187

     quadrats 190, 192

   random distribution 172

   samples

     location distribution 177

     size 176–7

     subdivision 177–81

   sampling strategy 176–7

   standardisation 174–5, 176

   statistical manipulation 177

   subsamples 177–8

   timed species counts 178

   transects 143–4

   unstandardised observations 174

freshwater

   ammonium-ion measurement 391

   nitrate-ion measurement 391

   nitrogenous compounds 391

   phosphorus-compound measurement 398

   phytoplankton 207–8

   Winkler titration 386

funnel traps 288

   reptiles 303

funnel-box traps, reptiles 298

fur clips, seals 366

fyke nets 270, 269–70, 271

gamebirds, dropping counts 339

Gantt charts 7

gaps between samples 23

generalised models

   additive 76–7

   linear 75, 74–6

Geographical Information System (GIS)

   functionality of system 15

   vegetation mapping 198, 199

GEOMEAN program 82

germination tests, seedbank sampling 205

gill netting 267, 266–7, 269

   advantages 268

   bias 268–9

   disadvantages 268

   selectivity 268

glassware for water chemistry 385

Global Amphibian Assessment (IUCN) 279

Global Positioning System (GPS)

   aquatic-vegetation mapping 200

   gradsects 196

   lake-vegetation mapping 201

   pitfall-trap randomisation 224

   vegetation mapping 198, 199

glue, lizard catching 301–2, 304

Go Flow Flask 381

goodness-of-fit tests, mark–recapture studies 103–7

gouge auger 399–400

grabs, invertebrate censusing 244–5

gradsects 197

   plants 196, 197

grain of scale 371

graphs 1

   drawing 4

   required 2–3

grass tussocks 220

   vacuum sampling 226–7

grids, points on 22–3

ground-nesting species, bird surveys 333–4

groundwater, nitrate-ion measurement 391

habitats

   disturbance in reptile capture 298–9

   fish 251

   frequency of occurrence 175

   sampling for complete counts 90–1

hair catchers, mammal 365–6

hair tubes, mammal 365–6

hand nets 287

hand-capture of reptiles 297–301

   advantages/disadvantages 300

   bias 300–1

hazards, water chemistry 383–5

Heath traps 234–5

hibernation-site monitoring of bats 355

hides, tower 334

histograms 3, 4

home range of mammals 365

hook and lining, fish 265–6

humidity measurement 375–6

hydroacoustics, fish catching 271–2

hydrographs 375

hydrometers 383

hygrometers 375–6

identification

   accuracy 137

   invertebrates 215

immigration, trapping webs 149–50

index of numbers 13, 155–67

   abundance 174

   calibration 165, 163–6, 167

     biologically based 167

   correction factors 161

   counts

     density estimates 157

     part of population 156–7

   cue counting 157

   double sampling 168, 169–71

   extrapolation 167

   ideal 155–6

   minimum known to be alive 157

   multiple, randomised observations 158

   non-linear relationships 164, 167

   ratio 155–6

     estimators 167

     population density 161–3

     variation 158–61, 167

   regression techniques 161

   standardisation of methods 158

   timed species counts 179

   two-way analysis of variance 159–60

   value comparison 158

   variation 158–67

     allowing for 159–61

   see also population indices

indicator paper, pH measurement 376

indicators 80–3

   multi-species population 83

indigocarmine staining 206

infectious diseases

   amphibians 293

   bat colonies 356

   mammal handling 362

information criterion of Akaike 76–7, 119

   POPAN software 182

Integrated Population Monitoring programme 70

interception methods for sample counts 152–4

interception traps, invertebrate censusing 231–2, 237

inter-observer variability

   bankside counts for fish 252

   cover estimates 197

invertebrates

   abundance-change monitoring 214–15

   aquatic

     bait traps 243

     direct searching/observation 240–1

     emergence traps 243–4

     kick sampling 245

   beating of foliage 228

   benthic cores 244–5

   capture 220–1

   censusing techniques 216–20

   cylinder samples 242–3

   dessication funnels 239–40

   digging 238–9

     for benthic 244–5

   direct searching/collecting 216

   direct searching/observation 220–2

   emergence traps 237–8

   evaluation surveys 214

   extraction from substrate 216–19

   exuviae counting 221–2

   fixation 219

   fogging 228–9

   grabs 244–5

   identification 215

   interception traps 231–2, 237

   kick sampling 245

   killing 219–20

   light traps 234–6

   litter samples 239–40

   preserving 219–20

   as prey 215

   prey abundance 215

   sampling 215

   soil cores 238–9

   sorting 215

   storing 219–20

   survey commissioning 215–16

   sweep netting 225–6

   trapping 216

   vacuum sampling 226–8

   water traps 232–4

   wet sieving 244–5

   window traps 231–2

   see also Malaise traps; pitfall traps

IUCN Global Amphibian Assessment (GAA) 279

jack-knife methods 32

Jolly–Seber mark–recapture method 89, 120–2, 128

   bird surveys 330–1

   capture histories for batch-specific marks 122

   goodness-of-fit test 126–7

   main calculations 123–5

   preliminary calculation 120–1

   software packages 182

kick sampling, invertebrate censusing 245

killing, invertebrates 219–20

killing bottles 219

Kipp solarimeters 379

knowledge of species 13

kriging 67

labelling, invertebrate specimens 220

lag of scale 371

lakes, vegetation mapping 201

larvae, amphibian 278–9

Lepidoptera

   counting along transects 221

   preserving 219–20

lift netting 264

   fish 263–5

light measurement 378–80

   aquatic 380

   percentile absorption 380

light meters, underwater 380

light traps

   bias 236

   invertebrate censusing 234–6

likelihood ratios 119

Lincoln index 330–1

line intercepts

   animals associated with definite tracks 154

   counts 153–4

   cover 153

   differences from line transects 146

   plants 196

   tracks 153

line transects 145–6, 147

   advantages 323–4

   from the air 322–4

   bird surveys 323, 319–24

     ground-nesting 333–4

   counting instructions 319

   density estimates 321, 323

   detection function 356–7

   disadvantages 323–4

   distance bands 321–2

   distance between 321

   distance estimation 319, 321

   distance sampling 319–20, 321

   frequency distribution 143

   length 321

   mammal counts 354, 357, 356–7, 358

     aerial surveys 358

   methods 320–2

   perpendicular distance 145, 356, 357, 358

   point counts 324

     comparison with 148, 326

   recording 321–2

   routes 320–1

   at sea 322, 324

   trapping 152

   triangular 321

   visit numbers 321

   walking speed 319

lines, fishing 265–6

litter samples, invertebrate censusing 239–40

lizard grabber 301–2

lizards

   arboreal 304

   glue traps 301–2, 304

   hand-capture 297–301

   noosing 301–2

Longworth traps 360–1

Lugol’s iodine solution 208

Lund counting chamber 209

lures, small lizards 301

McKinnon lists 178, 312

macrophytes, aquatic 200

Malaise traps 230

   bias 231

   invertebrate trapping 216, 229–31

   window–trap combination 231

mammals 351

   aerial surveys 358–9

   aquatic 157, 351, 359, 360

     colony counts 366–7

   bat roosts/nurseries 354–6

   call counting 360

   colour variation 359

   decision tree for census techniques 352

   DNA recovery

     dung 363

     hair 366

   dung counting 363–4

   footprint counts 364–5

   hair tubes/catchers 365–6

   herbivore feeding signs 364

   home range 365

   individual recognition 359–60

   infectious-disease risk 362

   line transects 354, 357, 356–7, 358

     aerial surveys 358

   nesting structures 354

   photography 351–2, 358

   quadrats 354

     dung 363

   resting structures 354

   runway counts 364–5

   strip transects in aerial surveys 358

   territoriality 365

   total counts 351–2

   trap types 360–1

   trapping 360–2

     dung-count calibration 363

   undercounting 352, 358–9

management change monitoring 72

Mann–Witney tests 4

mapped variables, spatial variation of numbers modelling 66

mapping censuses

   bird surveys 317

   individual plants 210–12

maps 3

MAPS (Monitoring Avian Productivity and Survival) programme 328–9

marine coastal systems, water-flow measurement 374

MARK program 127, 182

   mammal trapping 362

   ring-recovery models 182

marking methods

   batch-specific 120–2

   behaviour effects 136

   bird surveys 344

   counts 91

   at each capture 114–15

   individual 114–15, 122

     plants 210–12

   loss of marks 94–5

   mark–recapture techniques 94–5

   not needed 98

   reptile 305–6

   resighting 95–8

   seals 366

   without capture 136

mark–recapture methods 94–129

   amphibians 280–1, 291

   ancillary-information use 127

   availability for trapping 99

   bias 125–6

   Burnham and Overton method 114–18, 128

   burrow-nesting birds 333

   capture

     histories for batch-specific marks 122

     occasions 98

   catchability 100, 103, 108–10

     differences 99–100

   choosing between methods 118–19

   closed populations 98

   Craig and du Feu continuous capture-and-recapture method 132–3, 134–5

   goodness-of-fit tests 103–7

   hook-and-line fish capture 266

   individual recognition of mammals 359

   mammals

     individual recognition 359–60

     trapping 362

   models

     modified 127

     robust 128

   multiple recaptures in closed populations 102–19

   open populations 98

   population estimates 100, 101, 102–3

   primary periods 128

   proportion captured 99, 100–1

   radiotelemetry 127

   reptiles 306

   resightings 127

   robust model 73

   Schnabel method 112–14

   seals 366

   secondary periods 128

   simulation models 119

   simultaneous 132

   trap responses 99–100

   trappability

     differences 99–100

     heterogeneity 115

   trapping effort 107–8

   trapping-grid area 128–9

   trapping webs 151–2

   two-sample methods 100–2, 101

   Wileyto et al. method 132, 133

   without capture 98, 136–40

   see also capture–mark–recapture methods; Jolly–Seber mark–recapture method; pseudo-removal method; removal method

maternity colony monitoring of bats 355

maximum-likelihood estimates

   N-mixture models 141

   POPAN software 182

mean (statistical) 26, 25–7

   calculation of geometric 82

   cluster sampling 55–7

   random sampling 46–7

   sample-size estimation 29

   stratified sampling 48

   two-level sampling 44–5

metal sheets, reptile capture 298

migration

   bird counts 337–8

     diurnal species 337–8

     nocturnal songbirds 338

   continuous 154–5

   funnels/bottlenecks 337–8

   sample counts 154–5

   stop-over sites 155

minimum known to be alive (MNA) 157

mirrors, tree-nesting-bird colonies 334

mist nets 329, 342

monitoring 67–85

   adaptive management 67–70

   birds 308

   filters 78–9

   indicators 80–3

   indices 158

   management changes 72

   multiple sample sites 74

   population

     estimates 158

     long-term trends 72

     short-term variation 72

   programme

     consistency 84–5

     method changes 84

     planning 83

     review 83–4

   single sample sites 73–4

   statistical significance 79–80

   surveillance 68–70

   target setting 68

moon-watching, nocturnal-songbird migrant counts 338

mortality, marking potential impact 95

mouse glue, lizard catching 301–2, 304

mudflats

   penetrability 400

   redox potential 405

multi-level sampling 43

   costs 38

   optimal distribution 38

   precision 38

   two-level 43

multiple-catch traps 361

multi-state models 183

National Vegetation Classification (UK) 198

negative binomial distribution 30

   zero-inflated 32

nest counting

   bird colonies 331–5

   failure rate in bird surveys 332

   mammals 354

net bags, vacuum sampling 227

net traps, tortoises 303

nets

   cast 263

   drum 303

   electrofishing 255

   fyke 270, 269–70, 271

   hand for amphibian netting 287

   invertebrate capture 220–1, 225–6

   lift 263, 264

   mesh size 268, 271

     fish-egg collection 274

   mist 329, 342

   monofilament 268–9, 274

   multifilament 268–9

   plankton 208, 208, 274–5

   purse seine 258–60

   push 263–5

   selectivity 268

   trammel 267, 268

   turtle capture 300

   twine 268–9

   water-transported seeds 202

   see also gill netting; seine netting; trawling

netting

   amphibians 287, 291

     removal studies 290

   pond 241–2

New Jersey trap 236

Niskin Flask 381

nitrate ions 389

   measurement 391, 392

nitrate probes 390–1

nitrogen, soluble 389

nitrogenous-compound measurement 389

   water-testing kits 399

N-mixture models 140–1

noosing, reptiles 301–2

noosing gun 301

null hypothesis 79–80

numbers

   changes with repeated counts at same site 60

   spatial-variation modelling 65–7

   tests of equality 103–4

   tests of trends 104–5

observation-based methods 183

   amphibian individual-recognition methods 280–1, 282

   fish

     bankside counts 251–3

     egg visual estimates 273

     underwater 253

   invertebrate censusing 220–2

     aquatic 240–1

occurrence see frequency of occurrence

orthophosphate 396

otter trawl 261, 262

Owen emergence traps 237, 238

oxidation–reduction potential 405

oxygen

   dissolved 386, 385–9

     percentage concentration 389

     water-testing kits 399

   soils/sediments 405–6

   solubility in water 390

   water sampling 388

oxygen electrode 386, 389

paint marks

   reptiles 305

   seals 366

passive-integrated-transponder (PIT) tags

   amphibians 281, 282

   reptiles 305

patch sampling, amphibians 289–90

patchiness, plants 187–8

penetrometers 400, 401

percentage relative precision (PRP) 14, 15

   population trapped 108

   pseudo-removal method 111

   removal method 111

   sample size 27

     random sampling 28–9

   two-level sampling 42–3

percentile absorption 380

Petersen method 330–1

pH measurement 376–7

   dissolved-oxygen meters 389

   soil 404–5

pH meters

   ammonium/nitrate probes 390–1

   redox-potential measurement 405

phosphorus

   dissolved 396

   particulate 396

   soluble reactive 396, 396, 398

phosphorus-compound measurement 396–8

   water-testing kits 399

photography

   aerial vegetation mapping 198–200

   amphibian skin-pattern recognition 280

   birds

     migrant 337–8

     nest counting of colonial 332

   mammal counts 351–2, 358, 366

     individual recognition 359

   plant mapping 212

   seals 366

   see also cameras, miniature

photometers 379–80

photon flux density 378–9

   energy-flux conversion 379

   equipment 379

   underwater light meters 380

photon irradiance 378–9

photosynthesis, limitation by turbidity 380

photosynthetically active radiation (PAR) 379

phytoplankton 207–9

   density estimates 208–9

   preservation 208

pie charts 3–4

pilot study 13

pinning, Lepidoptera preserving 219–20

PIT tags see passive-integrated-transponder (PIT) tags

pitfall traps 223

   advantages 224

   amphibians 285, 285–6, 288

   baited 224

   bias 224–5

   disadvantages 224

   drift fencing 285, 285–6, 302–3

   emptying 224

   invertebrate trapping 216, 222–5

   mammals 361

   methods 222–4

   nocturnal beetles 215

   positioning 224

   preservatives 223

   randomisation 224

   reptiles 302–3

   tortoises 303

plankton nets 208, 208

   for fish eggs 274–5

planning

   reverse 1, 2, 10

   revision 10

   time availability 7–8

plant pots, mesh-based 202, 202

plant-available water 403–4

plants 186–8

   abundance 186–7

   belt transects 196, 197

   classification 188

   counts 188–9

   cover 197

   gradsects 196, 197

   line intercepts 196

   mapping/marking of individual 210–12

   phenological differences 188

   photosynthetically active radiation (PAR) 379

   quadrats 189–94

     gradsects 196

     point 194–5

   rare species 195

   seed traps 201–3

   sessile 187–8

   taxonomic groupings 188

   transects 196–7

   see also algae, benthic; phytoplankton; seedbanks; seeds; vegetation, mapping

playback, response to in bird surveys 341–2

   burrow-nesting species 333

point counts 150

   bird surveys 319, 323, 324–6

     playback of songs/calls 341

   density estimation 148

   distance bands 325

   distance estimation 325

   distance sampling 148

   edge effect 148, 149

   frequency distribution 144

   subdivided 140

   underwater observation of fish 253

point frame 195

point quadrats 152, 194–5

point sampling, electrofishing 255–6

Poisson distribution 30, 75, 105

   continuous capture and recapture 133

   goodness-of-fit test 105–7

   N-mixture models 141

   zero-inflated 32

   zero-truncated 105, 107

Poisson equation 168

poles, fishing 265

pollutants

   nitrogenous compounds 389

   phosphorus compounds 396, 398

pond netting

   aquatic invertebrates 241–2

   bias 242

pooters 221

   invertebrate capture 220–1

POPAN program 182

population

   absolute size 272

   closed

     continuous capture and recapture 132

     continuous mark–recapture method 132

     mark–recapture 128

     mark–recapture studies 98, 125–6

     multiple recaptures in mark–recapture studies 102–19

     testing for 96–7

   comparing two or more areas 62–5

   counts of part 156–7

   long-term trends 72

   loss from 120

   mean and repeated counts at same site 60–2

   monitoring process 69

   multi-species indicators 83

   open

     mark–recapture studies 98, 125–6, 128

     multiple recapture 119–27

     testing for 96–7

   peak and repeated counts at same site 60–2

   recruitment to 120

   short-term variation 72

   size estimation

     cluster sampling 54–7

     territory mapping 318

   unified analysis across sites/times 73

population density

   index ratio 161–3

   mammal trapping 362

population estimates

   invertebrates 221

   mammal trapping 362

   mark–recapture studies 100, 101, 102–3

   monitoring 158

   precision 19

   software packages 181–3

   total size 27

population indices 155–67

   birds 308

     playback of songs/calls 341–2

   capture techniques in bird surveys 328

population size

   bird surveys 308

     capture techniques 328, 329, 331

     playback of songs/calls 342

   mammal trapping 362

   total 27

pot gear 270, 269–70, 271

precision 14

   average-number estimates 25

   cluster sampling 34

   cost balance 14

   measurement 14

   multi-level sampling 38

   population estimates 19

   repeated counts at same site 58

   sampling 20, 27

   stratified sampling 49–50

preservatives, pitfall traps 223

preserving, invertebrates 219–20

prey abundance, invertebrate censuses 215

probability (statistical)

   critical 79

   N-mixture models 141

process models 77

productivity, post-fledging 329

propylene glycol 223

   Malaise traps 230

   water traps 233–4

protocols 1

   design 4–5

pseudo-removal method 108, 107–10, 111

   goodness-of-fit test 110–12

   percentage relative precision 111

push netting, fish 263–5

quadrat boxes

   aquatic habitats 289

   invertebrate censusing 221

quadrats

   abundance measures 191

   advantages 192–4

   amphibians 289

   bias 194

   disadvantages 192–4

   ground-nesting-bird surveys 333–4

   mammal counts 354

     dung 363

   multiple 190

   nested 192–3

   permanent 211

   plants 189–94

     gradsects 196

     individual mapping 211

   point 152, 194–5

quantum radiometers 379

questions, research 1

   results required 2–4

   specific 2

radar, bird counts 338

radio tracking, bird surveys 344

radiometers 379

   quantum 379

radiotelemetry 127

rain gauges 374

rainfall measurement 374

random distribution

   abundance 172

   occurrence 172

   T-square sampling 93

random sampling 36–7, 53

   plotless sampling for complete counts 91–2

   sample size 28–9

random strips 24

randomisation

   comparing two or more study areas 65

   computer-intensive 32

randomised blocks 66

   complete 65

randomness 20

   deviations from 20–3

raptors, migrant counts 337–8

ratio estimators 167

reagents for water chemistry 385

recapture

   multiple in open populations 119–27

   software packages 181–2

recognition, individual

   amphibians 281, 280–1, 282

   mammals 359–60

     DNA in dung 363

   vocal in bird surveys 342–4

   without capture 136–7

recruitment, multiple-recapture methods 120

redox potential 405

regression analysis 4

   data from single site 73–4

   generalized linear models 74–6

   route 77

regression techniques, indices of numbers 161

RELEASE program 182

remote sensing

   gradsects 196

   vegetation mapping 198–200

removal method 108–10, 130, 129–30

   amphibians 290

   detectability in bird surveys 327

   goodness-of-fit test 110–12, 112

   percentage relative precision 111

representativeness in sampling 19–20

reptiles

   activity periods 299

   aquatic species 300

   autotomous 299

   bags for holding 300

   baits 303

   black plastic sheets 298

   box traps 303

   branding 305

   capture 297

   drift fencing 302–3

   drum nets 303

   ectothermy 297

   ethics of studies 306

   funnel traps 303

   habitat disturbance 298–9

   hand capture 297–301

   individual marking 305–6

   mark–recapture methods 306

   nocturnal 299

   noosing 301–2

   paint marks 305

   pipes in capture 299

   PIT tags 305

   pitfall traps 302–3

   scale clipping 305

   searching techniques 298

   sticky traps 304

   surveys 297

   tattooing 305

   tin sheets 298

   toe-clipping 305

   trapping 302–4

     advantages 304

     bias 304

     disadvantages 304

research

   to action 70

   design 1

   questions 1, 2–4

   surveillance 68–70

resightings 127

   bird surveys 330–1

   marked-animal mixing 95–6

resting structures, mammal counts 354

results, required 2–4

reverse planning 1, 2

   revision 10

ring-recovery models 182

ringing

   capture–mark–recapture methods 330

   constant effort in bird surveys 329, 330

     response to playback use 342

river banks, invertebrate censusing 220

rivers

   kick sampling 245

   vegetation mapping 200

Robinson traps 235, 234–5

rocky shores, zonation patterns of taxa 374

rods, fishing 265

roost counts

   bats 354–6

   bird surveys 335–6

rotational sampling 72

route regression 77

runway counts, mammals 364–5

safety, water chemistry 383–5

salinity measurement 382–3, 384

   conductivity conversion 382

salinity meters 383

   hand-held 383

sample(s) 13–14

   cluster numbers 38

   gaps between 23

   layout 33–67

sample counts 94–129

   distance sampling 141–52

   double-observer method 137

   double-survey method 140

   interception methods 152–4

   migrating animals 154–5

   N-mixture models 140–1

   subdivided point counts 140

   trapping methods 129–36

   whole area 136

   see also mark–recapture methods

sample sites

   area differences 63–4, 65

     randomised blocks 66

   management-change monitoring 72

   multiple 74

   multiple visits 58–60

   single 73–4

   unequal area 31

   unplanned loss 71–2

sample size

   estimation 27–9

   random sampling 28–9

sample units 18, 20

   clustering 34

   distance travelled 24

   size 24–5

   two-dimensional distribution 21

   unequal 29–30

   units to sample 27–9

sampling

   adaptive 51–4

   bias 20

     sources 15–16

     unavoidable 23

   cluster 36–7

     population-size estimation 54–7

   definitions 18

   design 14–15

     for surveillance 71–2

   distribution

     normal 30

     not normal 30–2

   effort-optimal allocation 49–50

   frame 18, 19

   inaccessible areas 22

   intensiveness 22

   invertebrates 215

   location distribution 177

   multi-level 43

   objectives 13

   plotless 91–2

   points on grids 22–3

   precision 20, 27

   random 20, 36–7

     deviations from 20–3

     statistics 46–7

   regular 21–2

   replication need 18–19

   representative 19–20

   rotational 72

   strategy for frequency of occurrence 176–7

   stratified 49, 43–50, 51

     precision 49–50

   two-level 41–3, 43, 101–2, 177

     percentage relative precision 42–3

     statistical calculations 44–5

   unified analysis across sites/times 73

   using same location for surveillance 71

   see also cluster sampling

sampling-unit shape 23–4

sand tracking 364–5

satellite imaging, vegetation mapping 198–200

scale, ecological 371

scale clipping, reptiles 305

scan searching, amphibians 286–7

scattergrams 3, 4, 29–30

scents, footprint tracking 365

Schnabel method 113, 112–14, 115

   goodness-of-fit test 116

science, community relevance 68

SCUBA diving 253, 254

   aquatic vegetation 200

   fish-egg collection 274

   roving transects 253–4

sea/seawater

   conductivity measurement 381–2

   line transects 322, 324

   nitrate-ion measurement 391

   nitrogenous compounds 391

   phosphorus-compound measurement 398

   phytoplankton 207–8

   salinity measurement 382–3

   Winkler titration 386

seabirds

   line transects 322, 324

     from the air 322

   radar migrant counts 338

seals/sea lions

   call counting 360

   colony counts 366–7

searching in invertebrate censusing 216, 220–2

   aquatic 240–1

   standardised 221

Seatest Specific Gravity Meter 383

Secchi disc 380

sediments

   benthic algae 209–10

   characteristics 399–405

   marine 405

   oxygen content 405–6

   particle-size measurement 402–3

   redox potential 405

   seedbank sampling 204

   shear strength 400–2

   water-transported seeds 202

seed rain 203

seed traps 202, 201–3

seed trays 202

   germination tests 205

seedbanks

   germination tests 205, 206–7

   sampling 204–7

   seed counting 206

   soil samples 204–5

seeds

   chilling 205, 206–7

   counting 206

   distribution in soil 207

   dormancy 205, 206–7

   germination 202–3

     tests 205, 206–7

   identification 202–3

   predation 203

   viability 203, 206

seine netting 259, 257–9, 260

   advantages 260

   amphibians 287

   bias 260

   disadvantages 260

   purse nets 258–60

shear vane 400–2

Sherman traps 361

shore

   height above 378, 377–8

   zonation patterns of taxa on rocky shores 374

simulation models, computer-based 16

simulations 17

skin-pattern recognition, amphibians 280, 282

Skinner traps 234–5

slope angles 377–8

smoothing techniques 74

snake tongs 299

snakes

   hand-capture 297–301

   venomous 299–300

snorkelling 253, 254

snow

   mammal tracking 364–5

   measurement 374

soil

   Bouyoucos method 402, 403

   characteristics 399–405

   classification of types 399–400

   clay fraction 403

   moisture 403–4

   organic content 404–5

   oxygen content 405–6

   particle size 402, 402

   penetrability 400, 401

   pH measurement 377, 404–5

   profiles 399–400

   silt fraction 403

   surface hardness 400

   textures 402, 404

soil cores 204

   bias 239

   invertebrate censusing 238–9

soil pits 399

soil samples, seedbanks 204–5

solarimeters 379

sonar, hydroacoustics for fish catching 271–2

songbirds, nocturnal migrant 338

songs, bird

   response to playback 341–2

   vocal individuality 342–4

sonograms 342–4

sorting, invertebrates 215

sound spectrograms 342–4

spatial patterns, kriging 67

spawn, amphibians 287

Spearman’s rank correlation coefficient 96–7

   critical values 97

species

   assemblage-change monitoring 215

   indicator 82–3

   knowledge of 13

species detection, McKinnon lists 178

species distribution 168

   clumped 168, 171

species diversity, underwater observation of fish 254

specific gravity 383, 384

spectroradiometers 379

spreadsheets 16–17

   simulations 17

standard deviation, sample-size estimation 29

standard error, calculation 26, 25–7

standardisation of methods, index-ratio variation 158

statistical significance 79–80

statistics 4

   frequency of occurrence 177

   normality assumption 30

   not normal distribution 30–2

   random sampling 46–7

   spreadsheets 16

   two-level sampling 44–5

Stevenson screen 375

sticky traps

   reptiles 301–2, 304

   seeds 201–2, 203

stop-over sites, migration 155

storage of invertebrates 219–20

stratification 43–51

   spatial-variation-of-numbers modelling 65–6

   technique 47–8

stratified sampling 45, 43–5, 51

   bootstrapping 51

   confidence limits 51

   costs 48

   effort allocation 48

   intensity 48

   post-stratification 48–51

   stratum size 51

   stratum weight 48

   strip transects 51

streams, kick sampling 245

stress of capture 361

strip transects 52–3

   differences from line transects 146

   mammal counts with aerial surveys 358

   stratified sampling 51

strips

   sampling units 23–4

   size 25

study-area comparisons 62–5

subsampling

   frequency of occurrence 177–8

   mechanical extraction 91

   timed species counts 178

substrate, invertebrate extraction 216–19

sugar bait for moths 236

sulphides 405

sunshine duration 377

Surber sampler 246

SURGE program 182

   multi-state model 183

surveillance 67–70, 85

   alert systems 77–80

   filters 78–9

   generalized models

     additive 76–7

     linear 74–6

   indicators 80–3

   process models 77

   route regression 77

   sampling design 71–2

   statistical significance 79–80

   targets 78

   time scales 78

surveying sins 408–10

SURVIV program 137, 182

   multi-state model 183

   ring-recovery models 182

survival rate

   adult birds 329

   stop-over sites 155

suspended solids monitor 381

sweep netting, invertebrates 225–6

swimbladders 272

swimming speed, underwater observation of fish 253

t tests 4

tables 2–3

   number required 2

tags, reptiles 305

tail-scute removal, crocodiles 305

tape loops 341

target setting 68

targets 78

tattooing of reptiles 305

temperature

   call-rate effects 162

   conversion 375

   difference measurement 379

   measurement 374–5

territoriality, mammals 365

territory mapping 166

   advantages 318

   bias 318–19

   bird surveys 314–19

     playback of songs/calls 341

     singing 318–19

   breeding season 314–15

   disadvantages 318

   map analysis 315–18

   scale 314, 315

   study-plot mapping 314

tetrazolium staining 206

thermographs 375

thermometers 374–5

   wet/dry bulb 375–6

thermopiles 379

three-point moving average 74

throw netting of fish 263–5

time

   allocation 7–8

   availability 5–7

   scales 78

timed species counts (TSC) 178, 179

   bird surveys 313–14

tin sheets, reptile capture 298

toe-clipping

   amphibians 280, 282

   reptiles 305

tortoises

   hand-capture 297–301, 303

   pitfall traps 303

tower hides 334

tracking

   line intercepts 153

   sand 364–5

   snow 364–5

tracking strips in bird surveys 340

trammel nets 267, 268

transects

   amphibians 289–90

   bird surveys 319–26

     playback of songs/calls 341

   electrofishing 255–6

   fixed for underwater observation of fish 253

   invertebrate censusing 221

   permanent 211

   plants 196–7

   roving for underwater observation of fish 253

   see also line intercepts; line transects; point counts; strip transects

trap responses, mark–recapture studies 99–100

trappability

   continuous capture and recapture 133

   differences 99–100

   heterogeneity 115

trapping

   amphibians 288–9, 291

     removal studies 290

   barriers 269–71

   behaviour effects 136

   crocodiles 303–4

   designs 361–2

   effort 107–8

   fish 269–71

   invertebrate censusing 216

   line transects 152

   mammals 360–2

     dung-count calibration 363

   multiple sessions 362

   reptiles 302–4

   sample counts 129–36

   selectivity 271

   see also mark–recapture methods

trapping grid 361, 362

   area 128–9, 361, 362

   square 129–30

trapping line transects 152

trapping webs 151, 148–51, 152

traps

   bait

     aquatic invertebrates 243

     crocodiles 303–4

     fish 269

   funnel 288, 303

   funnel-box 298

   mammal 360–1

   see also baits; named types of traps

trawling 260–3

   advantages 263

   bias 263

   depth 261

   disadvantages 263

   nets 262

   speed 261

tree-canopy fogging 228–9

tree-nesting-bird colonies 334–5

TRIM program 75

T-square sampling 92, 92, 93

turbidity measurement 380–1

turbidity meters 381

turtles 300

   basking sites 303

   flipper tags 305

tussocks

   invertebrate censusing 220

   vacuum sampling 226–7

two-level sampling 43

two-sample method 40

   mark–recapture methods 100–12, 112

UK indicators for birds 81

ultraviolet (UV) light 379

vacuum sampling 226

   advantages 227

   biases 227–8

   disadvantages 227

   invertebrates 226–8

   method 226–7

variables, mapped 66

variance

   calculation 25, 26–7

   cluster sampling 55–7

   clustering 30

   homogeneity 37

   spreadsheets 16–17

   stratified sampling 48

variation

   numbers over time 61–2

   quantification in field 8

vegetation

   beating 228

   groundtruthing 199

   invertebrate censusing 220

   mapping

     aquatic 200–1

     ground 198

     terrestrial 197–200

   types 198

     point quadrats 195

     quadrats 190

     transects 197

   vacuum sampling 226–7

vocal individuality, bird surveys 342–4

volunteers, bird monitoring 308

water

   conductivity measurement 381–2

   filtering 381, 381

   free-draining 403–4

   light measurement 380

   oxygen

     sampling 388

     solubility 390

   pH measurement 376–7

   phosphorus compounds 396

   plant-available 403–4

   plant-unavailable 403–4

   reagents for water chemistry 385

   sampling 208

   seed transport 202

   seedbank sampling in sediments 204

   total nitrogen 389

   turbidity measurement 380–1

   see also freshwater; sea/seawater

water chemistry 383–5

   safety 383–5

water flow 371–2

   measurement 372–4

water-testing kits 390, 399

   phosphorus-compound measurement 396

water traps 233

   bias 234

   invertebrate censusing 232–4

waterfowl, line transects from the air 322

wave action 374

websites, software packages 181

weirs 269–71

wet sieving, invertebrates 244–5

whales

   call counting 360

   counts 155, 351

   cue counting 157

   individual recognition 359

wildfowl, dropping counts 339–40

Wileyto et al. mark–recapture method 132, 133

wind

   direction and wave fetch 374

   flow 371–2

wind gauges, hand-held 372

wind vanes 372

wind-velocity measurement 372

window traps

   bias 232

   invertebrate censusing 231–2

Winkler titration 386, 386

wire-mesh traps 361

zero counts 32

zooplankton, cylinder samples 242–3

Zurich–Montpellier vegetation classification 198




© Cambridge University Press