Date: Tue, 1 May 2001 23:50:01 EDT Reply-To: Maryland Birds & Birding Sender: Maryland Birds & Birding From: Kurt Gaskill Subject: Re: Huntley Meadows (what's happened?) Comments: To: VA-BIRD@list.audubon.org, huntleymeadows@erols.com MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Gail and all, I recently reviewed Bent's Life History for most of the No. America rails and have come to the conclusion that King Rail breeding habitat requires the presence of marsh bushes/shrubs as an important element in the breeding of this species; this element is probably valuable to provide shelter from predators (and at Huntley, that is Barred Owls, as approx. 5 pairs breed in the park). There is also other data (from Huntley staff) that King Rail nests in the past have been found in shrubby areas. Finally, let me note that the habitat at Huntley has clearly changed in the last 2-3 years with the marsh shrub component being greatly decreased. In the last 2-3 years there has been a significant increase in the beaver population at Huntley. I have observed large areas of the marsh that were mainly shrubby disappear in a matter of weeks just 2 years ago. I have observed beaver eating these plants. These areas, on the east side of boardwalk in the main pond area and the area south of the tower, often were locations where King Rails were frequently observed. There is also a lack of shrubs - often isolated - in other areas of the marsh. It is possible that Canada Goose population pressure has played a role in reducing marsh ground cover, but this species is unlikely to greatly affect shrub cover in the marsh. I have recently proposed that beaver damage is the primary cause of reduction of marsh shrub density. Let me also note that there are other areas at Huntley where rail habitat may be found, but these locations are seldom censused. With regard to wintering of King Rails, the CBC data shows no reports once or twice each decade since the 80's. There are two locations for King Rails in the Fort Belvoir CBC database - Huntley and the Occaquan Refuge in Woodbridge. If you will allow me to ignore the effect of reduced shrub cover, then extensive freezes may be the likely reason for no overwintering birds in those years. This past winter certainly fell into that catagory. But I should note that for the Jan 2000 CBC, only one King Rail at the Occaquan Refuge was recorded. Also, tonight Edna Aaron reported to me that she heard a King Rail at the Jackson Abbott Refuge Sunday (Fairfax Co, near Ft Belvoir). This area is contiguous with Huntley (forest and watershed) and is a reasonable place to find a migrant. It does have an extensive shrub base. As many of us know, nature often moves in cycles, sometimes for reasons we understand and sometime not. It may take time for the reasons of King Rail population fluctuation at Huntley to be fully understood. (Not to mention the other migrant rails.) So any information reported will be useful. Kurt Gaskill ======================================================================= To leave the MDOsprey list, send e-mail to listserv@home.ease.lsoft.com with the following message in line 1: signoff mdosprey ======================================================================= =========================================================================