Investigating the relationship between goldcrests, conifers and arborists

I LOVE reading about the goldcrest (Regulus regulus) and watching Britain’s smallest native bird darting in and out of the foliage to secure its daily diet of insects. The UK countryside and wildlife alliance waxes about the goldcrest, but wanes when it comes to conifers. Recently, I was treated to a stimulating account of the goldcrest and the usual dark, satanic diatribe about conifers all on the same day. 

There’s a clear contradiction here, because goldcrests are heavily reliant on conifers. The dense outer branches of spruces, firs and cypresses, including the much-maligned Leyland cypress, are almost exclusively the nesting sites for the ‘petit’ passerine. In addition, evergreen conifers provide cover against predators such as the sparrowhawk, while offering some thermal protection against periodic hard winters. According to the British Trust for Ornithology (BTO), the exceptionally harsh winter of 2009/2010 caused goldcrest populations to fall by as much as 60 per cent as far afield as Scotland and south-west England. Fortunately, goldcrests are able to recover and rebound just as quickly after a succession of mild winters, with their capacity for two broods of ten nestlings each per year.

Here in Hertfordshire, conifer forest plantations are few and far between. Clear-felled areas are generally not restocked, while the Forestry Commission hasn’t exactly gone out of its way to encourage conifer planting in southern England as a whole. Indeed, a dearth of restocking and new planting coupled with a continuing policy of converting existing conifer woodland into open habit, in areas like East Anglia, almost certainly means the total area of conifer woodland in England is actually decreasing.

Despite a clear statement from Sir Harry Studholm (FC chair 2014–20) that “non-native species must be part of the mix if the UK is to meet its tree-planting targets”, the ‘cull the conifer’ cabal carries increasing sway. The miserly amount of conifer planting in Hertfordshire is hardly surprising. Recent FC figures show just 200 ha of new conifer planting across the whole of England in 2020 – try dividing that up between 48 ceremonial English counties.

I do see goldcrests from time to time in parks and cemeteries, but only because these places have conifers not otherwise available in commercial plantations. And for that I can thank far-sighted Victorian estate owners who planted the trees. Many estates have subsequently been sold or bequeathed to local councils so that our public parks still have some of the same conifers – Scots and Corsican pine, Atlantic and Deodar cedars and Norway spruce – at least 150 years old. 

Broadleaved deciduous woodland is only used by goldcrests when conifers like spruce, fir and pine are also present. So think before you cull every single conifer from broadleaved deciduous woodland, even ancient woodland, lest you consign the goldcrest to oblivion in your neck of the woods.

Some years back I had goldcrests in my suburban back garden and almost certainly thanks to the half dozen big Leyland cypress trees and an equally large Lawson’s cypress which adorned the space. The Leyland cypress trees eventually had to come down one by one, but always well after bird-nesting season had ended.

Reliance of suburban goldcrests on the much maligned but still widely planted and worked on Leyland cypress in parks, on golf courses and in gardens is something which should be borne in mind. Ian Chedgy, a consultant arborist based in Wells, Somerset, told me how he frequently comes across goldcrests’ nests in cypress hedges.

“The nests are very small, far out on the foliage and therefore easily dislodged by summer hedge trimming,” said Ian. “Hence the requirement to prune Leyland cypress hedges outside of the accepted period for bird nesting.” He wonders whether this nesting behaviour is a defensive strategy against nest raiders like magpies and squirrels, which are perhaps too heavy to get out onto the thinner branches. 

These Leyland cypress trees came down one by one, but only after the ‘close season’ ended, this one on a fine mid-October day. Work was carried out by climbing arborist Patrick Osborne, owner of Height & Light of Hertford in Hertfordshire.

Under the European Habitats 1992 Nesting Birds Directive there is a 1 March to 31 August ‘close season’ on hedge cutting and trimming. Whether or not that still pertains in post-Brexit UK is anyone’s guess. However, given that resident birds like robins are starting to breed in February under the influence of climate warming, and three to four brood species like blackbird breeding up to the end of July and beyond, the existing close season should be adhered to, whether or not it is still the law. 

One of my last three goldcrest sightings was in a local cemetery during a particularly warm April. The goldcrest was darting in and out of a rapidly re-foliating hawthorn tree and eating insects, but with the safety of tall Austrian pines and dense Lawson’s cypress nearby. The goldcrest’s natural diet is almost exclusively comprised of insects. In autumn and winter they may range in flocks with other very small passerines like the long-tailed tit and even be tempted at the bird table, especially by mealworms mixed with suet.

Another sighting was during March in the local public park, originally laid out as the garden of a country estate in the late 18th century, now featuring a range of conifers, some of which are well over a century old. I was sweeping the top of a veteran Norway spruce with my binoculars to see if it was bearing cones, when I came across a pair of goldcrests feeding on whatever insects the tree had to offer. 

The location of the last sighting is as intriguing as the birds themselves. It was on common land at Monken Hadley on the very edge of north London, with a long and a distinguished history. It was the site of the last battle in the Wars of the Roses and the village church (St Mary the Virgin) still has a fire beacon on its tower. This was reputedly lit as one of a chain on 19 July, 1588, to warn of the approaching Spanish Armada. 

The common is wet, acid grassland but well-endowed with trees including many Scots pine (Pinus sylvestris) which regenerate freely from seed. There is little danger of these pine trees being removed, but elsewhere, on common land outside of London, conifers are being felled in significant numbers. First and foremost this is because of the continuing focus on creating and re-creating open habitat, supported by a contention that Scots pine is not native to southern England, due to the belief that sometime in our not too distant history Pinus sylvestris  was wiped out by man’s activities. Even though the species was one of the first to come across the land bridge after the last ice age and clearly colonised southern England first. 

Leyland cypress hedges are popular as living screens on golf courses and are almost certainly popular with the local goldcrest population.

Dr Roderick Robinson, who lives on the edge of the North Yorkshire Wolds, says goldcrests regularly frequent his garden, which is well-endowed with evergreen conifers.

“There are mature specimens of Scots and Corsican pine, Norway spruce and a variety of cypresses, all frequented by goldcrests,” he said. He believes the densest conifer canopies afford the best protection for them. 

“They are never still for a moment and are constantly on the move, darting about the foliage. They are curious birds and, if one is patient and quiet, they will always come out to investigate the intruder. 

“They are most easily detected by their song, which carries readily at a very high pitch. It reminds me of someone trying to start the engine of a miniature toy car, always failing to do so, time and time again – but in this case, the battery never runs down. In spring they seem to range more widely and can spend hours distracted by their own reflection in the window panes of the house, especially where there is a dense shrub close by to hide in.”

Message to the eco-warriors: if you value the goldcrest you need to encourage conifers because you can’t have the bird without the tree. This includes the much misjudged Leyland cypress, which has secretly been kept in reserve as a timber tree should something nasty like Phytophthora ramorum happen to Sitka spruce, and threaten by far the largest part of commercial softwood timber production in the UK. 

Leyland cypress trees are the most commonly worked on garden tree, but also a preferred nesting site for goldcrests in suburban areas. Climbing arborist Patrick Osborne seen at work here.

One of many admiring quotes I have seen about its the timber and wood is: “Leyland cypress wood turns nicely, has interesting grain patterns and polishes to a soft lustre.

Leyland cypress has apparently been approved as structural timber in Australasia, which makes sense since the wood is light, strong and rot-resistant.”

And I can testify to its rot-resistance. I keep all my logs as deadwood and for decoration around the garden. The Leyland cypress logs are still going strong today, whereas wild cherry, silver birch, horse chestnut and sycamore – felled at the same time – are now well on their way to humus.