Species Diversity

I did briefly mention this topic to one or two people at the Xmas bash, but would appreciate comments from others.

Around 15 years ago I fed birds regularly in my garden with the usual seed, nuts and fats. At that time I noted many species of birds who visited the garden to feed on a regular basis. We had large numbers of Great, Blue and Coal tits, with a few Long Tailed tits and Goldcrests occasionally using the food. It was not unusual to have four or five Blackbirds and Song Thrushes at anytime feeding. We also had Tree Sparrow, House Sparrow, Dunnock, Robin, Wren, Chaffinch, Greenfinch and Starling. Both Lesser & Greater peckers were on the feeders daily. There are probably species I have missed out of the list but the general idea is that there were a broad range of birds at the feeders most of every day in winter.

Since I started feeding in the garden again a couple of weeks back I have noticed a massive drop on numbers and species compared to 15 years ago. The only regular feeders in any numbers are Great, Blue & Coal tits. Nuthatch appear daily and I did have two sightings of Lesser Pecker as reported on the blog. But I have only had the odd finch visitor (Chaffinch & Greenfinch), no other finches have been seen. I do get Robin and Blackbird, but no thrushes.

The point of all this is an apparent species crash in Park Wood in the last 15 years or so of woodland songbirds. I don't regularly walk the wood anymore as you can be run down by off road motorbikes or mountain bikes at any time of day or night. Its also a haunt of idiots with air rifles who like to think they are great white hunters cos the bagged a couple of Squirrels. Now I realise that all the things mentioned above have probably contributed to some degree in a decline of birds in the wood. It could also be some sort of change due to a lack of understory growth in the wood making nesting sites scarce. But I suspect that one major factor in the huge surge in numbers of Grey Squirrels which are now numbered in their hundreds in the woods despite the attentions of the aforementioned great white hunters. Now I didn't want to get into the murky waters of controlling the numbers of squirrels in the wood, but surely if the picture in Park Wood is mirrored nationally we have had a truly catastrophic drop in song birds of woodlands nationally ?

Not being a regular birder and thus not being abreast of the latest reports on song bird decline in woodlands (I have seen a read reports of farmland bird decline) is this species diversity decline a common feature in Calderdale woodlands ? I would assume (and again only being a learner am happy to be shot down if wrong) that hole nesting birds such as tits, peckers and nuthatches are less prone to nest robbing by Squirrels than other birds and this is the reason they have not declined ?

I should also day that the national decline in bird numbers and diversity is reflected in the world of moths. I have taken part in many discussions as to why our moth populations have declined so dramatically in the last 30/40 years. This decline is also possible a reason why some birds have declined also due to the massive lost biomass of food potentially available to birds from moths.

I know I have rambled on a bit here but as no one is posting much on sightings at the moment it is a quiet time to slip in my beginners questions