Unusual feeding patterns among birds at a Sussex wildlife centre shows we could be in for a cold winter, according to experts.

Staff at Arundel Wetland Centre noticed their birds were eating exceptionally large amounts of feed two weeks ago when the weather was still unseasonably mild.

They believe the birds realised a cold snap was on its way and were attempting to gain weight and put on an extra layer of fat to stave off the chilly weather.

Grounds manager Paul Stevens said: "It is remarkable the way some of the ducks are eating through their feed like it is going out of fashion.

"We feed them special food pellets and check the feed hoppers every day but we were staggered that they were emptying them very rapidly."

James Sharpe, the centre manager, said it is not clear whether the unusual feeding pattern means the current cold spell will last throughout the winter, but said: "Birds are tuned into weather systems and can anticipate changes in the weather.

"They have a sense of what's happening with the weather that we couldn't begin to grasp.

"It may be we are in for a cold winter or it may just be a shorter cold snap."

The centre, which is owned by the Wildfowl and Wetlands Trust (WWT), has a collection of captive wildfowl but also plays host to migratory swans, ducks and geese who fly in for the winter.

Colleagues at the WWT's headquarters in Gloucestershire have also noted some unusual behavioural patterns among wild Bewick's swans arriving at the centre.

The birds breed in Arctic Russia over the summer before flying south for the winter.

There are currently 45 swans at the centre, yet at the same time last year there were 33 and in 2005 just 17.

It is not known whether they migrated early because they sensed favourable weather systems on their route ahead or because the weather was getting colder in Russia.

Meanwhile human forecasters at The Met Office say the cold weather will continue into the next week. They are predicting sunny spells tomorrow and Friday, as well as overnight frost and fog patches.

Over the next week temperatures are expected to remain below normal with a strong, chilly north-easterly wind.

Longer-term weather predictions are still experimental, and are based primarily on the influence of ocean temperatures on the European winter climate.

Currently data suggests that this winter is likely to be colder than last winter, when exceptionally mild conditions were widespread across Europe.

However, temperatures are not expected to drop below average.

Meanwhile country dwellers have reported heavy crops of berries in the hedgerows, which is traditionally an indicator of a hard winter coming.

Have you noticed any fat birds in your garden? Tell us below.