From south-bay-birds-bounces+south-bay-birds-archive=[[email protected]] Fri Nov 19 20:31:55 2004 Received: from www.plaidworks.com (localhost [127.0.0.1]) by plaidworks.com (8.12.9/8.12.9) with ESMTP id iAK4TFjn010132 for <[[email protected]]>; Fri, 19 Nov 2004 20:29:16 -0800 (PST) Received: from imo-d23.mx.aol.com (imo-d23.mx.aol.com [205.188.139.137]) by plaidworks.com (8.12.9/8.12.9) with ESMTP id iAK4RhVC010084 for <[[email protected]]>; Fri, 19 Nov 2004 20:27:43 -0800 (PST) Received: from [[email protected]] by imo-d23.mx.aol.com (mail_out_v37_r3.8.) id t.1a5.2af81c32 (4246) for <[[email protected]]>; Fri, 19 Nov 2004 23:27:34 -0500 (EST) From: [[email protected]] Message-ID: <[[email protected]]> Date: Fri, 19 Nov 2004 23:27:34 EST Subject: Re: [SBB] Coe Birds To: [[email protected]] MIME-Version: 1.0 X-Mailer: 8.0 for Windows sub 6811 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Content-Filtered-By: Mailman/MimeDel 2.1.5b1 X-BeenThere: [[email protected]] X-Mailman-Version: 2.1.5b1 Precedence: list List-Id: South Bay Birding List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: south-bay-birds-bounces+south-bay-birds-archive=[[email protected]] Errors-To: south-bay-birds-bounces+south-bay-birds-archive=[[email protected]] In a message dated 11/19/04 4:22:53 PM Pacific Standard Time, [[email protected]] writes: > I have been compiling records from the park since 1984 and this current > irruption of montain species is unprecedented. I have a few records for small > numbers of crossbills. Red-breasted Nuthatch numbers currently at the > Monument exceed the total number of individuals I have prior records for. Pygmy > Nuthatch is a new species for the park. > > Where are all these birds coming from? If I had to guess, I would suggest > the Santa Cruz Mountains as a possible source. All three species are resident > there; the distances are close and no additional vagrant species suggestive > of the Sierra Nevada as a source have been found at Coe during this invasion. > One can never know where these guys are coming from, but I'd suggest that the Santa Cruz Mountains are unlikely to be the source for the Red Crossbills or Red-breasted Nuthatches at Coe. The concept of resident crossbills in the Santa Cruz Mountains is somewhat a matter of how one defines residency. While some have been present rather locally in the S. C. mountains year-round over recent years, they are not (IMHO) truly resident (always present) in any one area, and they are often pretty sparse. There are patterns of increases and decreases that are hard to predict, often local, and increases are often short-lived. Perhaps some small number are truly resident, as much as a crossbill can be, but there is clearly turnover and the whole issue is hard to suss out. There was a pattern of an influx into these mountains in late summer. I believe those were birds coming from away from the local area. I believe our local breeding Red-breasted Nuthatches are largely resident and do not seem to wander much, except fairly close to nesting areas. Unlike the populations in the Sierra Nevada, the overall local breeding population is not particularly large, and does not seem to me to be sufficient to create a notable invasion elsewhere were they to emigrate, assuming they would disperse over a sizable area. Plus, at least where I have looked, the areas of local occupancy are still presently occupied by the usual numbers, and local seed sources seem to be fairly plentiful. The coastal slope of the Santa Cruz Mountains also had an influx of RBNUs this season, with the timing typical of occasional fall influxes of birds from afar. My impression from reports elsewhere in the state was that both Red Crossbill and Red-breasted Nuthatch were on the move to some degree on a broad scale. While other montane species may be lacking at Coe, there have been a few Townsend's Solitaires in the Santa Cruz Mountains. My read of the local data for irruptive montane species has suggested that years with a whole suite of montane irruptives in our local area are rare, but having one or a few irruptives in a given year is the normal pattern. David Suddjian Capitola, CA [[email protected]] _______________________________________________ Do not post admin requests to the list. They will be ignored. south-bay-birds mailing list ([[email protected]]) Help/Unsubscribe/Update your Subscription: http://www.plaidworks.com/mailman/options/south-bay-birds/south-bay-birds-archive%40plaidworks.com This email sent to [[email protected]]