Part 7: A Bit of Knowledge About the Eurasian Jay

Eurasian Jays – The Secretive Forest Collectors

The Eurasian jay (Garrulus glandarius) is a shy but colorful member of the crow family, easily recognized by its pinkish-brown body, black moustache stripe, and striking blue wing patches. Although often hidden within the forest canopy, jays play a crucial ecological role — they help oak trees spread by burying acorns, many of which later grow into new trees.

These clever birds are most common in woodlands and forest edges but also visit parks and gardens, especially in autumn and winter when food becomes scarce.

Diet

Insects:
Feed on caterpillars, beetles, and spiders, especially during spring and summer.

Seeds and nuts:
Use their powerful beaks to crack open acorns, hazelnuts, and other hard-shelled foods.

Fruits:
Eat berries and wild fruits from forest plants, and sometimes take fallen fruit from the ground.

Special Adaptations

Eurasian jays are expert foragers with a remarkable memory.
They are famous for caching — hiding acorns, nuts, and seeds in the ground to retrieve later during winter.
Not all of these hidden treasures are found again, allowing new oak trees to sprout naturally.
This makes the jay an important species for forest growth and regeneration.

Jays also use a variety of vocal calls to warn other birds of predators and can mimic the sounds of other species, including hawks.

General Feeding Guidelines for Corvids

Avoid:
Salt, spicy food, chocolate, coffee, alcohol, bread with additives, and raw or untreated meat (risk of illness).
If meat is offered, it should be cooked, unsalted, and given only in small amounts.

Limit:
Sugary foods or those high in fat, which can cause health issues.

Unlimited (with care):
Fresh fruits and vegetables such as apples, bananas, corn, carrots, and berries.
Cooked rice and plain cooked pasta can also be offered.

Limited amounts:
Small portions of high-quality cat or dog food, boiled eggs, cheese, cooked boneless fish, and grains.

Feeding Guide for Eurasian Jays

Note:
These are general recommendations. For precise advice about local bird species, consult wildlife experts or rehabilitators familiar with corvids in your area.

Biology and Behavior

Tool use and feeding: Uses its beak skillfully to break open nuts or dig up cached food — behavior that shows planning and intelligence rarely seen in birds.

Appearance: Pinkish-brown plumage with blue and black wing markings; strong, curved beak.

Habitat: Forests, woodland edges, and large parks.

Family life: Lives in small family groups; pairs often stay together for life.

Breeding: Lays 4–6 eggs; chicks fledge after around three weeks.

Distribution in Denmark: Widespread and common in deciduous forests throughout the country.

Seasonal behavior: Breeds in spring; caches food in autumn; may visit towns and gardens in winter.

Communication: Loud, rasping “kraak” or “kraa” calls used for alarm or contact; can imitate other birds.

Lifespan: Typically 10–12 years in the wild.

Diseases: Susceptible to parasites, bacterial infections, and respiratory illnesses.