Date: Tue, 22 Feb 2000 09:02:30 EST Reply-To: Maryland Birds & Birding Sender: Maryland Birds & Birding From: Gail Mackiernan Subject: Re: What a difference on the other side of the pond In-Reply-To: Message of Mon, 21 Feb 2000 22:24:23 -0500 from THis is a subject which probably is worth discussing on Mdosprey, since we too are seeing ominous declines in many bird species. Sometimes the reasons for the declines appear mysterious. It is probably very tempting to identify a simple cause to which we can apply a simple solution... Actually, BTO considers changes in farming practises to be the major cause of decline of field-oriented birds such as Corn Bunting and Skylark. Many of these changes are the result of EC agreements on crops, etc. Other species such as Red-backed Shrike, which my husband Barry recalls as a frequent breeder within an hour of his home in south London in the late 50s & early 60s, which has declined as dramatically as our Loggerheads, the reasons are equally uncertain. Although persecution by egg-collections, a particularly strange British pasttime, has not helped! Neither do the British cats which take an estimated 25 to 40 million songbirds a year. I wonder how many of the Songbird Survival group own cats which they allow to run at large? Climate change has also had an impact, according to many British ornithologists -- species associated with warmer temperatures, which are at the northern edge of their breeding range, are increasing (e.g. Dartford Warbler) while species such as Lesser Redpoll are declining. Afforestation in Scotland, as well as changes in landuse, possible inbreeding and even disease have been all implicated in declines in Balck Grouse and Capercaillie. Anyone who visits the UK will note how rare raptors are compared to the USA, although numbers are increasing after years of persecution and pesticide- induced declines. However, I don't think any ornithologist considers them a serious impact. There is some concern over potential impacts of increases of corvids, esp. Magpies, but again a lot of folks think these birds are getting a bum rap, too. Bird populations decline for a number of reasons -- it is usually a combination of factors -- and only rarely can "a" cause be identified. While it is true that predators can have serious impacts on populations which are already "at the brink" -- (e.g. impacts of Hawaiian Hawk on Alala, as presented at the last MC/MOS meeting) -- it isn't very likely to be the major factor in British songbird declines. There are a lot of things happening all at once in the British landscape, and it is probable that the major problem lies there. Gail Mackiernan ======================================================================= To leave the MDOsprey list, send e-mail to listserv@home.ease.lsoft.com with the following message in line 1: signoff mdosprey ======================================================================= =========================================================================