[CT Birds] I'm covering my eyes and ears as I send this
Mntncougar at aol.com
Mntncougar at aol.com
Thu Mar 29 20:51:41 EDT 2012
But I'm peeking!
It's relevant to the discussions of early arrivals.
Here's the link that all the data referred to below can be accessed
---------- Forwarded message ----------
From: Allen Chartier <amazilia3 at gmail.com>
Date: Thu, Mar 29, 2012 at 2:02 PM
Subject: [birders] RE: Michigan hummingbird arrivals - detailed reply
To: birders at umich.edu
I apologize for waiting 10 days to reply to your detailed questions
about Michigan hummingbird arrivals, but I'm in day 20 of a
respiratory infection and have also been trying to get all my bird
surveys done despite feeling bad (I don't get paid if I don't survey).
I've also been distracted with comments by a Massachussetts blogger
who discounted all the March hummingbird reports in the Midwest and
New England, heavily criticizing the www.hummingbirds.net website
which, oddly, he appears never to have encountered before despite it
being in operation since 1996. It appears that he didn't want to be
confused by the facts about this website, its data sources, record
vetting procedures, and photos supporting some records. Or, perhaps he
purposely avoided sending an email query to the owner of that site
because his own fact free version posted to his blog helps promote his
personal agenda better.
Anyway, on to the Michigan data. As you might know, I've been posting
Ruby-throated Hummingbird arrival maps since 2001, and added detailed
data tables in 2003. More than half of my reports comes from
www.hummingbirds.net, which consists of about 99% non-birders, but are
thousands of people who are very devout about feeding their
hummingbirds. I have posted the annual arrival maps and data tables to
my website here: http://www.amazilia.net/MIHummerNet/ObsData.htm.
If you go through each year's data, you will see that over the years
(2003-2011) there have been a total of 11 March reports in Michigan. I
have not been able to confirm a Ruby-throat from any of those 11, but
a couple were confirmed by the homeowners as unidentified hummingbirds
(I follow up on EVERY report before April 15 even though
hummingbirds.net does this too) and a couple were claimed to be
Ruby-throats but no photos were taken. So the difference this year is
that there are 18 reports in March instead of a maximum of 2. And this
year I feel confident in confirming 6 of those reports as Ruby-throats
(the earliest on March 18) and six others as unidentified hummingbirds
(see the 2012 data for these reports).
It was my intent to tally spring arrivals after 10 years of data,
which will be completed in 2012. But your inquiry about "bell curves"
spurred me to tally the data now :-) I have produced bar charts for
each year (2003-2011), and a composite of all these years combined. It
is interesting to look at the year-to-year variations, and you can
look at these graphs by clicking on the "Annual Spring Arrival Graphs"
on the data site above. You can see that almost every year sees birds
in mid-April but with the real peak occurring around May 5-10 except
for one year (2009) there was a large peak the last week of April.
P.S. I must take exception to your comments about population centers
and implying there aren't any in places like Tennessee. Maybe you
haven't been to Nashville, Knoxville, or Gatlinburg in summer
(yikes!)? And, actually there seem to be very few people in Detroit
who put out hummingbird feeders while there are quite a few in Oxford!
Allen T. Chartier
Email: amazilia3 at gmail.com
On Mon, Mar 19, 2012 at 6:56 PM, KALUZA, FRED <fk2751 at att.com> wrote:
> Allen, when Hummers move through a region, what is the nature of their “
curve”? Is it bell-shaped? What’s the standard deviation? Plus or minus
five days or five weeks?
> I might venture a guess that like other bird species, there are some
that are driven so hard to find choice nest sites, they move up north at their
own peril often finding nothing but snowflakes where others will find food
in a month. Then there may be others that are old and never even attempt
another northward trek and stay south until they die.
> I can believe that first arrivals could have been missed by people in
more sparsely populated climes only to be detected by people in more densely
populated places like Detroit.
> What would be harder to believe would be the reverse as in if they were
missed by everyone in Detroit only to be seen by someone in Oxford for
> I’m thinking that the people in Tennessee (being less densely populated
by observers) may actually be seeing something more like the rise to the
peak and not really the single outliers on the leading edge. For best
detection of first incoming you’d want your densest sensor placement at the
outermost perimeter right? Just a thought.
> Fred Kaluza
> AT&T Mobility Regulatory Compliance E911
> IWOS NP&E RAN E911-MW, IN & Detroit
> 16025 Northland Dr.
> Southfield, MI 48075
> Office 248.395.2992
> Fax 248.395.0176 or 248.395.0342
> Mobile 313.980.3002
> From: Allen Chartier [mailto:amazilia3 at gmail.com]
> Sent: Monday, March 19, 2012 5:38 PM
> To: birders at umich.edu
> Subject: [birders] Michigan hummingbird arrivals
> Hummingbird enthusiasts,
> As I have for perhaps the past 10 years, I intend to map and list in a
table the spring arrivals of Ruby-throated Hummingbirds in Michigan on my
website (page is not ready yet!). The earliest confirmed Ruby-throated
Hummingbird record is April 1, 2010. In some years I get reports of "glimpsed"
hummingbirds in late March. This year, I have already received three such
reports of unconfirmed species from March 17! In order to confirm a
hummingbird in March in Michigan, I'd really like to see a photo, for a couple of
reasons. First, the leading edge of Ruby-throated Hummingbird migration seems
to currently be in southern Tennessee, based on my favorite source for
this: www.hummingbirds.net/map.html. Second, it has been the best season in
several years for overwintering western hummingbird species, especially Rufous
but also including good numbers of Calliope and small numbers of at least
four other species, from New England south to Florida and west to
Louisiana. Any one of these could possibly pass through Michigan on its way back to
the breeding grounds, though we only have one confirmed spring record for
Rufous so far.
> So, what I'm recommending this year is for those in southern Michigan to
put your feeders out NOW, and keep your camera handy by the window sill.
My typical advice when asked (which is quite a lot) is April 15 but it
appears the weather pattern is set for warming not cooling. In northern
Michigan, you might want to consider putting your feeders out in mid-April this
year. We might not have a better chance to confirm a March hummingbird for
some time. And, I am following my own advice, and put out two hummingbird
feeders just this afternoon. But I'm not putting my snow shovel into the
basement yet either. This is Michigan, after all :-)
> Allen T. Chartier
> Inkster, Michigan
> Email: amazilia3 at gmail.com
> Website: www.amazilia.net
> Blog: http://mihummingbirdguy.blogspot.com/
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