When we first moved to Durham, nearly 40 years ago, nuthatches were not very common birds here. I can still remember the first one that I spotted, hammering away at a yew seed wedged into the fissures in the tree near Prebends bridge in Durham city.
Since then they have become very common birds throughout the county and it would be an exceptional day out if we didn't see or hear at least one. I saw these two within ten minutes of each other in Auckland Park, Bishop Auckland, last week - and heard two more there.
They are now frequent bird table visitors in winter too, and in spring their noisy courtship is a conspicuous feature of woodlands. Their numbers seem to have increased most noticeably in the last decade - although I'd have to concede that maybe I'm also becoming more aware of them.
Which begs the question "why have their numbers increased?". It can't be food supply because their staple food - tree seeds - can't have changed much. Climate change - the favourite driver for everything these days - seems unlikely too as these are hardy little birds. I can't imagine that there has been any decline in any particular predator either. Maybe bird table feeding has had some effect, but that can't be the only reason as I see them as often in remote places as I do around habitation.
It's all a bit of a mystery, but it's a delight to watch them feeding at this time of year, when there's a massive abundance of food for them to choose from.