Santa's reindeer will enjoy a mix of porridge, bird seed and cranberries. Photo: Lorne Gill/SNH

Families helping Rudolph and his friends on Christmas Day are being advised he doesn’t need a glittering trail to find his way.

Scottish Natural Heritage, the government outdoors adviser north of the border, said Santa’s reindeer friends prefer a mixture of porridge, cranberries and bird seed.

Adding plastic sparkle to a trail can harm wildlife, which may eat the remains of any trail not consumed by Father Christmas’s reindeer.

An SNH spokesperson said: “A carrot is traditionally a great option for Rudolph, but it is now becoming more common to sprinkle trails outside to guide the reindeer and to help them fly.

“However these trails are likely to be eaten by birds and other animals, making it even more important to keep any sparkles such as glitter or confetti out as they contain plastic and shouldn’t be consumed by any animal.”

The agency has come up with a perfect recipe to help Rudolph find his way to children’s homes and help him fly to the next one. It recommends mixing a small cup of porridge oats; one of bird seed, and a similar amount of dried cranberries to lay as a trail.

Des Thompson, SNH’s flying reindeer nutritional expert, knows all about what helps these magical animals fly. He said: “This hearty mix of porridge oats, bird feed and cranberries is just what the reindeer love to nibble on.

“The porridge keeps them going all through the night, the bird feed helps them fly and the red cranberries are not only one of their five a day but also the red colour keeps Rudolph’s nose shining bright.

“Oh, and don’t forget Santa, and his love of a sweet treat!”

The organisation said even ‘edible’ cake sprinkles intended for human consumption can give animals sore stomachs and other dried fruit such as raisins can be poisonous to dogs, so advises sticking to the advised mix.