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align=3D"left"><span class=3D"087022117-19122007"><font face This is a multi-part message in MIME format. --Boundary_(ID_4K3Ic2XQN5IXYSIGETkNFg) Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Hi Chris, The methodologies used by the Breeding Bird Surveys (BBS) and the first Maritime Breeding Bird Atlas to estimate populations are much different. The first atlas had nothing comparable to the point counts of the current atlas so had to rely on people taking educated guesses about the abundance of a species in their square(s). It's been a long time since I took part in the first atlas but I seem to recall that there were 5 or 6 fixed levels and the estimate was optional. The BBS provides a count of all birds seen or heard over a fixed duration along a route composed of 50 points. Given the completely different methods used its not surprising that numbers differ so radically. It will be very interesting to see the results of this atlas's point count information as it is much closer in methodology to that of the BBS. I'm not sure how the atlas indicates that the populations of both Belted Kingfishers and American Robins is stable or how you can definitively state that the BBS estimates are too high. The BBS trends are based on annual measurements of the same data collection points over 40 years. The first atlas was one snapshot in time. What are the estimates of the first atlas being compared to, the preliminary estimates of the current atlas? All the best, Lance ________________________________ From: naturens-owner@chebucto.ns.ca [mailto:naturens-owner@chebucto.ns.ca] On Behalf Of Christopher Majka Sent: Wednesday, December 19, 2007 4:38 PM To: naturens@chebucto.ns.ca Subject: Re: [NatureNS] Too many kingfishers in Nova Scotia?? Hi Lance, On Dec 19, 2007, at 1:35 PM, Laviolette, Lance (EXP) wrote: Hi Elizabeth and others, The 'estimated' population for whatever region is being asked about is based on the results of Breeding Bird Surveys (BBS). There are about 30 in Nova Scotia I believe. 16,000 (individuals not pairs) is not all that large an estimate for Belted Kingfishers really, when you consider a species such as American Robin will get you an estimated population of 3,000,000 for Nova Scotia. Also, it looks to me as though the estimated number is +/- %20. The Atlas of Breeding Birds of the Maritimes Provinces gives a Nova Scotia population of Belted Kingfishers of 4,100 +/- 1,600 pairs and a Nova Scotia population of American Robins of 370,000 +/- 130,000 pairs. If the above estimates you are referring to derive from BBS data then they are approximately 60% to high for kingfishers and 340% too high for robins. As far as the long term trend goes, you can go directly to the BBS trend analysis page and have a look at the data. It is found at: http://www.mbr-pwrc.usgs.gov/bbs/trend/tf06.html Since we're talking about Belted Kingfishers, the trend in Nova Scotia over the last 40 years is -4.67% (p=0.01) The Atlas indicates that populations of both species seem to be stable. Cheers, Chris --Boundary_(ID_4K3Ic2XQN5IXYSIGETkNFg) Content-type: text/html; charset=US-ASCII Content-transfer-encoding: 7BIT <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=us-ascii"> <META content="MSHTML 6.00.2900.3243" name=GENERATOR></HEAD> <BODY style="WORD-WRAP: break-word; webkit-nbsp-mode: space; webkit-line-break: after-white-space"> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2>Hi Chris,</FONT></SPAN></DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2></FONT></SPAN> </DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2>The methodologies used by the Breeding Bird Surveys (BBS) and the first Maritime Breeding Bird Atlas to estimate populations are much different. The first atlas had nothing comparable to the point counts of the current atlas so had to rely on people taking educated guesses about the abundance of a species in their square(s). It's been a long time since I took part in the first atlas but I seem to recall that there were 5 or 6 fixed levels and the estimate was optional. The BBS provides a count of all birds seen or heard over a fixed duration along a route composed of 50 points. Given the completely different methods used its not surprising that numbers differ so radically. It will be very interesting to see the results of this atlas's point count information as it is much closer in methodology to that of the BBS. </FONT></SPAN></DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2></FONT></SPAN> </DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2>I'm not sure how the atlas indicates that the populations of both Belted Kingfishers and American Robins is stable or how you can definitively state that the BBS estimates are too high. The BBS trends are based on annual measurements of the same data collection points over 40 years. The first atlas was one snapshot in time. What are the estimates of the first atlas being compared to, the preliminary estimates of the current atlas? </FONT></SPAN></DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2></FONT></SPAN> </DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2>All the best,</FONT></SPAN></DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2></FONT></SPAN> </DIV> <DIV dir=ltr align=left><SPAN class=256532423-19122007><FONT face=Arial color=#0000ff size=2>Lance</FONT></SPAN></DIV> <BLOCKQUOTE dir=ltr style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px"> <DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left> <HR tabIndex=-1> <FONT face=Tahoma size=2><B>From:</B> naturens-owner@chebucto.ns.ca [mailto:naturens-owner@chebucto.ns.ca] <B>On Behalf Of </B>Christopher Majka<BR><B>Sent:</B> Wednesday, December 19, 2007 4:38 PM<BR><