I saw up the thread somewhere a reference to open water and global warming. Also consider the increased use of heated birdbaths to provide water for birds. I have two myself and find it makes a huge difference in the numbers I see. Sue on Melody Lake, Edina
On Fri, Dec 7, 2018 at 2:22 PM <jeffbi...@charter.net> wrote: > I have seen many references to the idea that buckthorn causes diarrhea in > birds. Not this note but other articles. So here is a link to an article > that refutes that belief. I also have copied a relevant passage from the > article. > > > http://net-results.blogspot.com/2011/11/myth-busting-birds-buckthorn-and.html > > Quote from article below. > "Wherever it occurs, buckthorn tends to be distributed by birds. There are > two commonly held and frequently repeated notions about buckthorn fruit: > that it causes diarrhea in birds, and that birds in North America don't > "know" not to eat unripe fruit and can become very sick or even die from > eating it. (Actually, there is a third notion, that buckthorn fruit is > "junk > food." That isn't entirely true either, but it a subject of a future post.) > > > > > > Jeff Stephenson > 1323 28th ST SW > Rochester, MN 55902 > Cell: 507 254 8194 > Home: 507 289 7635 > -----Original Message----- > From: Wayne > Sent: Friday, December 7, 2018 9:41 AM > To: MOU-NET@LISTS.UMN.EDU > Subject: Re: [mou-net] Winter Robins > > Before I removed the buckthorn on my property, I had periodic flocks of > waxwings feeding on berries in January. I did some research and found the > following: While birds do eat buckthorn berries, it's often because it's > the > only available seed source. But buckthorn berries are not a good food > source. They're low in protein and high in carbohydrates and produce a > severe laxative effect in some animals. > Wayne Swanson Minnetonka > > On Thursday, December 6, 2018, 10:40:50 PM CST, Terence Brashear > <tpbrash...@gmail.com> wrote: > > I know when I ran the CBC for the Audubon Chapter of Minneapolis we found a > huge flock feeding on Buckthorn berries in Island's of Peace Park in > Fridley, MN in 2001. It was a flock of over 1000 birds. I think their > winter numbers are tied to food, and temperature. > > On Thu, Dec 6, 2018 at 6:18 PM JULIAN SELLERS <juliansell...@msn.com> > wrote: > > > I think hackberries play a role. I don't know when the cities began > > planting hackberry trees on boulevards, but I think it was not many > > decades > > ago. Most of the trees do not look very old. Did large crops of > > hackberries begin to appear within the last 10 or 15 years? > > > > On the 2008 St. Paul (North) CBC, my team had the area west of Cleveland > > Avenue and south of Marshall Avenue/Lake Street, extending south to the > > Ford Dam and west past the Hiawatha grain elevators in Minneapolis. We > > counted 808 American Robins. As I recall, about 650 of them were feeding > > on Hackberries on the Summit Avenue median in the two blocks between > > Cretin > > and Cleveland Avenues. > > > > It seems to me that robins become scarcer in late December, as the > > hackberry supply is depleted. > > > > Julian > > ________________________________ > > From: Minnesota Birds <MOU-NET@LISTS.UMN.EDU> on behalf of Rebecca > Field < > > rebeccafiel...@gmail.com> > > Sent: Thursday, December 6, 2018 6:21 PM > > To: MOU-NET@LISTS.UMN.EDU > > Subject: Re: [mou-net] Northern Raven/Number Winter Robins > > > > I just heard this evening that Robins eat Buckthorn berries. Of course, > we > > are trying to eradicate that invasive. I hope that isn’t causing less > food > > for the robins. > > > > Becky Field > > > > Sent from my iPhone > > > > > On Dec 6, 2018, at 5:36 PM, Jason Frank <jmfran...@gmail.com> wrote: > > > > > > It would be interesting to compare the data of outstate CBCs as well. > > > I haven't lived in Minneapolis during winter since 1997, and it seemed > > > noteworthy to me to see large numbers of robins in the winter. A few > > > years ago I visited Minnehaha Falls around Christmas and couldn't > > > believe how many there were, though I just figured they were local > > > birds who stayed for the open water along the creek and had reliable > > > food sources nearby. Those numbers from Val show a pretty stark > > > increase, which to my eyes fits the trend of climate change. > > > > > > But... having lived in the Lac qui Parle area since 09, I can't say > > > I've seen many impressive winter flocks except during the mildest > > > winters of the last decade, and those birds were usually seen in town > > > or at parks, and not out in the countryside for the most part. > > > > > > Since the Twin Cities urban heat island effect means the temperature > > > averages there would be trending warmer than elsewhere in the state, I > > > wonder if outstate robins have gotten into the habit of migrating into > > > cities and towns, rather than further south? Collating banding data > > > with rural CBCs might shed some more light on the case. > > > > > >> On 12/6/18, GREG ELIZABETH CLOSMORE <closmor...@msn.com> wrote: > > >> Buckthorn! > > >> > > >>> On Dec 6, 2018, at 4:32 PM, Val Landwehr > > >>> <0000012f44857088-dmarc-requ...@lists.umn.edu> wrote: > > >>> > > >>> I was intrigued by the discussion of whether in recent years > > >>> more robins are being seen during winter in the Twin Cities(Charles > > Neil, > > >>> Mary White and J. Baumann). I think that I > > >>> have seen more robins, particularly in large flocks, in > > >>> recent years. To put this hypothesis to the test I looked at the > > >>> results from four Christmas Bird Counts over the years that are > > >>> online at the Minnesota Ornithologists' Union website. The > > >>> Christmas Bird Counts I checked were Bloomington CBC, St. Paul > > >>> (North) CBC, Excelsior CBC and the Minneapolis (North) CBC. > > >>> I found a distinct trend of more robins being counted during > > >>> the counts since the winter of 1996 than were in prior years. > > >>> The numbers vary widely each year, but there is a distinct > > >>> inflection point around 1996 for a larger number of robinssince that > > date > > >>> than prior to it. Since 1996, the number ofrobins counted varies > > greatly > > >>> from year to year, but I don't > > >>> see any clear evidence that the numbers are continuing to > > >>> increase. > > >>> Average number of robins counted at Twin Cities CBCs: > > >>> Bloomington St. Paul (North) Minneapolis (North) Excelsior > > >>> Pre 21.2 17.1 2.5 > > >>> 5.3 > > >>> 1996 > > >>> 1996- 367.4 420.5 114.6 > > >>> 181.2 > > >>> 2017 > > >>> > > >>> Median number of robins counted at Twin Cities CBCs: > > >>> Bloomington St. Paul (North) Minneapolis (North) Excelsior > > >>> Pre 5 6 0 > > >>> 1 > > >>> 1996 > > >>> 1996- 278 255 26 > > >>> 132 > > >>> 2017 > > >>> I considered that the increased number of robins might reflect > > >>> more birders participating in these Christmas counts as well > > >>> as an increase in birding skills. If there are more skillful > > >>> birders involved in these counts I would expect a similar > > >>> increase in the counts of other species. So I looked at the > > >>> counts reported by the Bloomington CBC for the black-capped > > >>> chickadee, blue jay and dark-eyed junco. I didn't find any > > >>> trends or long term changes in the number of these species. > > >>> Therefore, I'm convinced that the increased number of winter > > >>> robins is real. > > >>> I didn't attempt to see if there is a link between the increasein the > > >>> number of robins counted and weather/climate. > > >>> That leaves a question in my mind. Are the larger counts just > > >>> a reflection that the Twin Cities population of robins has > > >>> increased but the same proportion of that population is > > >>> overwintering as in the past or have the overwintering habits > > >>> of the robins changed? > > >>> The CBC data speaks only to the presence of robins in December. > > >>> Maybe the only change is when the robins migrate to warmer > > >>> regions. Maybe if we had many years of counts for January and > > >>> early February we would find that the number of robins in > > >>> those months hasn't changed much over the years. As Manley > > >>> Olson pointed out, once the robins exhaust the availability of > > >>> crab apples, perhaps they head south and are now just as > > >>> uncommon in January and February as they were back in the > > >>> 1950s through 1980s. > > >>> Val Landwehr > > >>> Minneapolis > > >>> > > >>> ---- > > >>> Join or Leave mou-net: > http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > > >>> Archives: http://lists.umn.edu/archives/mou-net.html > > >> > > >> ---- > > >> Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > > >> Archives: http://lists.umn.edu/archives/mou-net.html > > >> > > > > > > > > > -- > > > Jason M. Frank > > > Ortonville Public Library > > > Founder & Vice President > > > Luddite Ornithologists League (LOL) > > > Big Stone County, Minnesota > > > > > > ---- > > > Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > > > Archives: http://lists.umn.edu/archives/mou-net.html > > > > ---- > > Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > > Archives: http://lists.umn.edu/archives/mou-net.html > > > > ---- > > Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > > Archives: http://lists.umn.edu/archives/mou-net.html > > > > ---- > Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > Archives: http://lists.umn.edu/archives/mou-net.html > > ---- > Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > Archives: http://lists.umn.edu/archives/mou-net.html > > ---- > Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > Archives: http://lists.umn.edu/archives/mou-net.html > ---- Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net Archives: http://lists.umn.edu/archives/mou-net.html
