The year, as I reported in the last issue, has continued to have mixed fortunes in the local wildlife with some interesting records some of which that were perhaps weather related and some significant absences. Perhaps most surprising is that the Water Rail that was featured in the winter issue last year has remained with us and can if one is lucky be seen from the board walk across the lake in Dulwich park, and was included in Dave Clark’s biennial park bird count. As far as one can tell it is a solitary bird so there is no likelihood of its having bred, but who knows, there is always next year if it can attract a mate.
We have had other unusual records. A migrating Arctic Tern was spotted flying over the park lake on October 11th. This is of course a coastal bird which breeds farther north in this country with large colonies in the northern isles and Iceland. It undertakes the massive migration to the Antarctic, farther than any other of our migrants. It is hard to distinguish from the Common Tern which does breed in inland waters including the London Wetland Centre, but this bird was identified by its call and its date which was judged too late for a remaining Common Tern.
On the same date two Bullfinches were seen on the lake island. In the 1970’s Bullfinches were one of our local residents but with the national diminution of finch populations they are less usually seen. Greenfinches and Chaffinches are now reduced in numbers and the flocks, traditionally known as Charms of Goldfinches seem smaller in number here. The Dulwich Park count this Autumn failed to reveal any Song Thrushes or Mistle Thrushes although Blackbirds and Robins are maintaining their numbers as are Tits and Wrens. Firecrests continue to thrive in Sydenham Hill woods and a total of four birds have recently been seen which may be the result of the breeding report reported in the last issue. Global warming is thought to be responsible for bringing more Firecrests into southern England which can be most easily distinguished by walkers in the woods from the much more common Goldcrests by their prominent eyestripe. Both species favour coniferous trees as food source.
Peter Frost, a regular reader, reported that he heard a Chiffchaff in full song in October. During October migrating Chiffchaffs will regularly join the Tit feeding flocks. The trigger for song as is the urge to migrate is the length of day, which in the autumn crosses over with the spring equinox. It is particularly Chiffchaffs that are still around at this time and this appears to stir the hormones into a mini breeding mode and they are frequently heard to sing.
Egyptian Geese are clearly colonizing us in greater numbers with a flock of eight being the largest group seen. They are of course not native and come from ornamental collections as many years ago were Canada Geese but are more decorative and so far less intrusive. That other non- native, the Ring Necked Parakeet is still growing its population and Daniel Greenwood reports his bad sight of the Autumn being a Parakeet removing Grey Squirrel kits from a Woodpecker hole. Species competition for holes may well become a wildlife issue.
Butterflies this year have also had a mixed record. Most evident in our gardens, particularly those with Buddleias have been Red Admirals, but these are largely migrants from the continent. Conspicuously absent have been Peacocks and Tortoiseshells and there have been very few Commas. These are our native breeders and it appears that they have once more had a bad year. Readers may also have noticed that there have been fewer of the usually abundant Holly Blue Butterflies in their gardens. This I am told is a cyclical phenomenon due to parasitism by a small wasp that itself then diminishes in number when it has exhausted its supply of host butterflies which then recover. We can therefore expect to see Holly Blues again in a year or two.
I see that my suggestion in previous issues that reduction in our small bird populations may be due to reduction in numbers of flying insects on which they feed is now being backed by some hard evidence. A lack of flying insects also means a lack of larvae on which our small birds need to feed. Whereas for example we have seen a few Daddy Long Legs (Crane flies) it is some time since I remember the well known Autumn plague of these insects. Of course their larvae are the Leather Jackets in our lawns much beloved by Starlings. And where are the Starling flocks that would descend in numbers for a leather jacket feast?
At the time of writing the season has suddenly switched to Autumn and the first flocks of Redwing have already arrived from Scandinavia. Perhaps with the variously named hurricanes that are regularly forecast there will be some wind- blown extra records. Having written this, a last minute record has come in, not strictly a Dulwich bird , but an Osprey was seen on 19th October flying over Forest Hill being mobbed by a Peregrine Falcon. Having become established as a breeding bird in the northern half of the country, migrating Ospreys are regularly reported in southern Britain in the Autumn. Here they will always be overflying so it helps to look upwards when opportunity permits.
Wildlife Recorder Peter Roseveare (020 7274 4567)