In this month’s wildlife column, Jono Leadley of the Yorkshire Wildlife Trust sees early signs of spring.

AN unusually mild spell of weather in early January certainly had an impact on Yorkshire’s wildlife.

At Yorkshire Wildlife Trust’s Askham Bog nature reserve, near Copmanthorpe, hazel catkins were bursting forth, while great tits and song thrushes sang their hearts out. Snowdrops and other early spring flowers were reported from across the county and cherry blossoms were being visited by brave bumblebees.

The mild winter weather may not be good for rhubarb growers, but it will help some bird populations recover following two severe winters. Stonechats and other small, insect-feeding birds have suffered tremendously. It seems that 2011 was a good breeding season and if the weather does not take a major turn for the worse, wrens, treecreepers, stonechats and others should soon bounce back.

Cold weather in February and northerly winds could still hamper the recovery of these species, but for the wildlife watcher they could also mean further arrivals of birds from higher latitudes.

Keen birders will be scrutinising the sizeable roost of gulls that gathers each afternoon on the floods at Wheldrake Ings to try and pick out a rarity. For the sharp-eyed this can be very rewarding, with several rare species possible, including Iceland, glaucous, Mediterranean and yellow-legged gulls.

These birds take advantage of society’s wasteful nature, feeding at local landfill sites. Each morning and afternoon, big gangs of gulls can be seen sedately travelling between feeding and roosting sites, bringing a touch of the Scarborough seafront to inland York.

In January, an adult Iceland gull was seen occasionally at Harewood Whin landfill site near Rufforth and resting in fields at Poppleton. This species looks like a small herring gull – the familiar seagull of the coast – but with pure white wingtips.

Another speciality of late February and early March will be the exhilarating sight of boxing hares. Boxing occurs among brown hares in order to establish mating rites.

Look out for small gatherings of hares and watch patiently. They will often sit around quite calmly, before a male, or ‘jack’ takes the initiative and approaches a female, ‘jill’. This can erupt into bouts of boxing and hectic chases as the jill rebuffs the jack. These can be spectacular in fields and meadows along the Ouse, Wharfe and Derwent, where hares sprint through floodwater, creating a dazzling spray.

On mild, sunny days watch out for butterflies emerging from hibernation. Butterflies have various strategies for surviving the winter. Some spend the winter as eggs, others find sheltered areas in which to pupate, the adults then emerging from the protective cocoons as temperatures rise.

Other species, like red admiral and small tortoiseshell, sit out the cold months among ivy or in outbuildings, as adult butterflies. It is these species that appear in the early spring sunshine, bringing a touch of colour to the sombre hues of winter.

Another splash of colour was provided by a firecrest, which appeared briefly in a York street early in the month.

This exquisite cousin of the much commoner goldcrest is a real jewel; vivid lime-green on the back, with a bronze shoulder patch, white belly, bold black and white eyestripes, which set off a dazzling yellow and orange crown.

Firecrests breed in the south of England, but small numbers pass through Yorkshire on migration and occasionally stay to winter.

There have been a number of sightings of short-eared owls, with a pair regularly hunting the grasslands at the south end of Wheldrake Ings late in the afternoon.

This stunning owl, which breeds in a few remote upland areas of Yorkshire, spends the winter in lowland areas with lots of rough grassland full of voles. There have also been a small number of ‘shorties’ seen regularly around Scagglethorpe Moor.

To find out more, check out ywt.org.uk, find them on Facebook or follow @YorksWildlife on Twitter.