Cyanocitta cristata
Plate — illustration to come
Year-round residentNative · New Jersey

Blue Jay

Cyanocitta cristata

Corvidae

The loud, brilliantly blue crested jay that most people either love or resent. Blue Jays are arguably the most ecologically important yard bird in New Jersey — they are single-handedly responsible for the northward spread of oak forests. They cache acorns for winter, forget many, and inadvertently plant thousands of trees per bird over a lifetime.

Identify by

How to spot one.

  • 9–12 inches — larger than a robin, smaller than a crow

  • Brilliant blue back, wings, and tail with black barring and white patches

  • Prominent black necklace across the throat

  • White face and belly, blue crest

  • Very loud harsh 'jay! jay!' calls; also mimics hawks

Voice

What it sounds like.

Best known for the harsh 'jay! jay!' scream; also imitates Red-shouldered and Red-tailed Hawks. Actual song is a soft, sweet, whisper-quiet warble only heard at close range.

Life & behavior

How it lives.

Highly intelligent — corvid family. Caches acorns and seeds in the ground; recovers many but forgets enough to plant oak groves. Alarm-calls at hawks and cats, alerting other yard birds. Migrate erratically — some go south each fall, some don't, and the pattern varies year to year.

At a glance

The spec sheet.

Status
Year-round resident
Size
9–12 inches
Present in NJ
Year-round
Native to NJ
Yes
Conservation status
stable
Family
Corvidae
Diet

What it eats.

Diet often shifts dramatically between breeding season and the rest of the year — especially for insectivorous birds that pivot to native berries in fall and winter.

Summer / breeding season

  • Acorns, beechnuts, other nuts

  • Insects (beetles, caterpillars, grasshoppers)

  • Berries

  • Occasionally eggs or nestlings of other birds

Fall / winter

  • Cached acorns and beechnuts

  • Sunflower seeds and peanuts at feeders

  • Persistent berries

Plants it uses

What it needs.

Native plants that feed this bird or provide shelter. Names in hydrangea link to the plant’s Field Guide entry.

  • Native oaks (Quercus)

    Fruit / berry source

  • American beech, hickory

    Fruit / berry source

  • Serviceberry

    Fruit / berry source

Sources

All About Birds (Cornell) · Duke Farms Fall & Winter Visitors