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Hi all, I skimmed through the Chronicle Herald article, and since I have received a few questions about loons and the Canadian Lakes Loon Survey lately I thought I'd share BSC's Latest News blurb with links to the 30-year report and related documents (which I assume the article was based on). You can also contact the CLLS Coordinator, Kathy Jones, directly (I've pasted her contact info below). "New Canadian Lakes Loon Survey Report 9 July 2013 - Bird Studies Canada recently published a report analyzing results from our Canadian Lakes Loon Survey. The document summarizes patterns in Common Loon reproductive success across Canada between 1992 and 2010. Select this link (http://www.birdscanada.org/about/media/RlsCLLS9July2013.pdf) for a media release we issued this week, summarizing the troubling trends revealed in our new report. Measured as the annual number of young produced per pair, reproductive success was higher in western Canada than in the east; decreased over time; was higher on larger lakes than on smaller lakes; and increased as acidity decreased. These patterns were likely linked to mercury pollution and acid precipitation. Our findings support further action to reduce emissions of mercury and the harmful components of acid precipitation. The report also demonstrates the importance of using citizen science programs to monitor wildlife as indicators of environmental stress. Visit our website to read the full report (http://www.birdscanada.org/volunteer/clls/resources/CLLSsummary.pdf) by Dr. Doug Tozer, Myles Falconer, and Debbie Badzinski, and for information about Bird Studies Canada's Canadian Lakes Loon Survey (http://www.birdscanada.org/volunteer/clls) . To volunteer, you can also email Kathy Jones at volunteer@birdscanada.org. We thank all our past and current members for making this research and analysis possible." Kathy Jones Ontario Volunteer Coordinator (Canadian Lakes Loon Survey) Bird Studies Canada P.O. Box 160 Port Rowan, ON N0E 1M0 volunteer@birdscanada.org www.birdscanada.org Toll Free 1-888-448-2473 ext. 124 -----Original Message----- From: naturens-owner@chebucto.ns.ca [mailto:naturens-owner@chebucto.ns.ca] On Behalf Of Stephen R. Shaw Sent: Tuesday, July 23, 2013 2:14 AM To: naturens@chebucto.ns.ca Subject: Re: [NatureNS] Loon Flotilla + peril unexplained Hi Dave, others I too read this front page headlined piece 'Loon population in peril' but had a deeper problem with it -- it didn't seem to make sense as written. If the breeding success rate for a stable population (neither expanding nor shrinking) has been correctly estimated at 0.48 chick per pair per year, and yet the current success rate is higher, ~0.59 (from memory, can't find the paper to check), that means that the population actually is expanding modestly, so what's the problem (not explained)? If anyone here is familiar with the actual study perhaps they could comment and expand upon the C-H article to clarify the story. Presumably this was a reporter from a journalism background who can't do numbers, and failed to understand an important part of the original survey and so did not report it. Is it that the breeding success rate used to be (say) 2.0 (meaning an aggressively expanding population) and that this rate has been steadily declining, such that extrapolation from data over several recent years suggests that in (say) 3 years from now the rate will drop below 0.48? That would be worth reporting, though extrapolation is always dangerous. For instance, a real decline in the rate might reflect the downward slope of a cyclical process which has yet to turn back up again, though I'm not suggesting grounds for optimism, given stories about lead sinker poisoning and effects of mercury. Steve (Halifax) Quoting David & Alison Webster <dwebster@glinx.com>: > Hi Rick & All, July 22, 2013 > For birds that potentially have about 22 breeding years, 0.48 > chicks per year.pair for steady state made me wonder if this reflects > attrition or failed pairing due to a shortage of nesting sites > (Lakes). If so then 0.48 is a meaningless statistic. > > Some years ago, early morning antics at Sunken Lake suggested that > the residents were declaring ownership of the lake in no uncertain > terms (sequence pasted below). > Yt, Dave Webster, Kentville > > START OF PASTE\\\\\\\\\\\\\\\\\\\ > Hi Dusan & All, Aug 19, 2003 > We saw similar strange antics in 2001, at about this time of year, > and I described them in a post of Aug 6, 2001 (pasted below with also > strange typos intact). A week or so later we saw a similar display. > Failing other ideas I thought it might be the loon equivalent > "This is my lake, buzz off". > DW > > \\\\\\\\\\\\\\\\\\\START OF PASTE > > Dear All, Aug 6, 2001 > On Saturday at Sunken Lake, Kings Co., we were surprised to see > two sets of young loons (1 small loon and 2 slightly larger imm. > loons) and at least three matures, having understood that there is > normally only one loon nest per small lake. > On Sunday morning, at about 8:00 a.m., we saw the repercussions > (perhaps) in the form of a showdown between two adult loons, most of > it obligingly staged within 200 yards of our cottage. One loon (L1) > flailed into view at the head of a cloud of spray, that was raised by > both wings hitting the water vigorously, and within seconds a second > loon (L2) followed. When > L2 got to within ~5 body lengths of L1, the chase began in the form of > a zig-zag, i.e. when L2 narrowed the gap too rapidly and was almost > withing striking distance, L1 would turn abruptly on one wing, L2 > would shoot harmlessly past and be ~8 body behind by the time it got > turned around again. At least once, L1 did a 180 and started chasing > L2. A third adult loon was nearby while this was going on, and make > low un-loon-like worried 'whoo' sounds at intervals. There was only > one strike and there was so much water flying I could not be sure that > there was contact. > The chase lasted at least ten minutes (watch not nearby) and ended > when the lead loon dived. Several minutes later the tail loon dived > and within the next 1/2 hour a loon took off, circled the lake and > then crossed it to fly to the NW. Several minutes later a second adult > loon did the same. > Are immature loons able to fly by now ? > Yours truly, Dave Webster, Kentville > > \\\\\\\\\\\\\\\\\\\ first END OF PASTE > > Dusan Soudek wrote: > >> Hi, >> a friend reports the following loon behaviours from Keji last weekend. >> Can anyone explain what went on her