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I have noticed there are no nuts and acorns this autumn. How will this affect our animals over the winter and could bird feed help to sustain them?

Sent in by Shirley Roberts, Carmarthenshire

A wild bird irruption (a large irregular migration) often indicates an issue with a food source. Jays migrating into the UK is a sign that their favourite food, acorns, is in short supply on the continent as well as in Britain. The jay isn't fond of crossing open water so to cross the North Sea suggests a poor acorn crop. The arrival of bramblings in significant numbers may also reflect a problem with the beech mast crop in Scandinavia.

Bees and bad weather

Whilst some trees like oaks produce good crops followed by bad crops in irregular cycles, some trees’ production of fruit, nuts and seeds are influenced by climatic factors. Pear trees for example that rely on insect pollinators, bees in particular, were left without pollinators during the main flowering season as a result of an extended wet and cool period that limited insect activity.

In years where oaks don't produce acorns, the oak tree has played a smart move. By not producing acorns one year the population of the creatures that have come to rely on acorns decreases, that oak tree may then produce a super-abundance of food the following season that the smaller numbers of acorn eating creatures cannot eat their way through.

Alternative diets

Winters are hard for wildlife, it will take it’s toll on all creatures this is part of the natural cycle. Those wild animals that are able to take advantage of other food sources will fare much better. Despite the lack of acorns, sweet chestnuts and hawthorns are both heavy in nut and berry and provide a tempting alternative. We are already seeing jays working hard to cache the chestnuts.

Providing supplementary food in your gardens is definitely a positive step for wildlife. Many birds rely on gardens for food and shelter, especially over the really cold winter spells, so providing a range of foods such as seed mixes, suet based foods and soft fruit is a top tip.