Isle of Anglesey — county
- Group
- True flies
- Peak month
- July
- Records since 2000
- 651
- Group
- True flies
- Peak month
- August
- Records since 2000
- 636
- Group
- Seaweeds and algae
- Peak month
- September
- Records since 2000
- 626
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 613
- Group
- Worms (annelids)
- Peak month
- September
- Records since 2000
- 606
- Group
- Beetles
- Peak month
- July
- Records since 2000
- 604
- Group
- True flies
- Peak month
- August
- Records since 2000
- 591
- Group
- True flies
- Peak month
- July
- Records since 2000
- 585
- Group
- Flowering plants
- Peak month
- June
- Records since 2000
- 585
- Group
- Bees, wasps and ants
- Peak month
- April
- Records since 2000
- 582
- Group
- True flies
- Peak month
- June
- Records since 2000
- 566
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 561
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 561
- Group
- True flies
- Peak month
- August
- Records since 2000
- 551
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 526
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 515
- Group
- True flies
- Peak month
- July
- Records since 2000
- 494
- Group
- Seaweeds and algae
- Peak month
- September
- Records since 2000
- 473
- Group
- True flies
- Peak month
- June
- Records since 2000
- 466
- Group
- True flies
- Peak month
- June
- Records since 2000
- 446
- Group
- Seaweeds and algae
- Peak month
- June
- Records since 2000
- 442
- Group
- True bugs
- Peak month
- September
- Records since 2000
- 437
- Group
- True flies
- Peak month
- July
- Records since 2000
- 413
- Group
- Mayflies
- Peak month
- April
- Records since 2000
- 409
- Group
- True bugs
- Peak month
- July
- Records since 2000
- 381
- Group
- True flies
- Peak month
- July
- Records since 2000
- 374
- Group
- Bees, wasps and ants
- Peak month
- June
- Records since 2000
- 353
- Group
- True bugs
- Peak month
- June
- Records since 2000
- 338
- Group
- True flies
- Peak month
- July
- Records since 2000
- 331
- Group
- True flies
- Peak month
- July
- Records since 2000
- 330
- Group
- Beetles
- Peak month
- May
- Records since 2000
- 306
- Group
- Spiders
- Peak month
- June
- Records since 2000
- 277
- Group
- Bees, wasps and ants
- Peak month
- July
- Records since 2000
- 274
- Group
- Seaweeds and algae
- Peak month
- May
- Records since 2000
- 266
- Group
- Seaweeds and algae
- Peak month
- April
- Records since 2000
- 262
- Group
- True flies
- Peak month
- July
- Records since 2000
- 262
- Group
- Liverworts
- Peak month
- October
- Records since 2000
- 259
- Group
- Butterflies and moths
- Peak month
- August
- Records since 2000
- 259
- Group
- Molluscs
- Peak month
- September
- Records since 2000
- 258
- Group
- True flies
- Peak month
- July
- Records since 2000
- 256
- Group
- Birds
- Peak month
- July
- Records since 2000
- 255
- Group
- True flies
- Peak month
- July
- Records since 2000
- 252
- Group
- Beetles
- Peak month
- June
- Records since 2000
- 250
- Group
- Seaweeds and algae
- Peak month
- August
- Records since 2000
- 241
- Group
- Spiders
- Peak month
- May
- Records since 2000
- 228
- Group
- True flies
- Peak month
- June
- Records since 2000
- 213
- Group
- True flies
- Peak month
- August
- Records since 2000
- 212
- Group
- True flies
- Peak month
- July
- Records since 2000
- 211