Date: 1/9/18 5:44 pm
From: <susan...>
Subject: RE: hummingbird mortality
Dear John and All,

I have been away from the computer today-- among other things, visiting
with hummingbird hosts in Greensboro. I banded their adult female
Rufous-- on the heels of recapturing a female Rufous in Apex yesterday
(who is back for her 4th winter). Both were very healthy adults. I will
post photos to the CBC Gallery as well as some details on the NC
Hummingbird FB page shortly...

So, this response is made ahead of reading all of the other posts sent
today (in addition to a couple private inquiries made to me in the last
couple days). This is because I deal with the debate about winter hummer
feeding each year-- regardless of the conditions.

Here in the Carolinas, the situation is, not surprisingly, different
inland than it is along the coast. Inland, cold hardy species such as
Rufous (our most likely winter guests-- dozens every season) and
Calliope (one or two a year) show up in Fall/early Winter each year.
These are birds that are extremely cold adapted, breeding when there is
snow on the ground at high elevation and/or latitude. Our winters, even
with the kind of cold we are experiencing, are not problematic as long
as the birds are healthy-- especially if they are experienced adults.
There are Rufous that even survive winter weather well to the
north/northwest of us with feeders but without any trouble.

It is important to note that Rufous (and other wintering species as
well) may well head south right after bad weather (when insect
populations are affected) in search of warmer conditions. (Banded)
hummingbirds assumed as being lost over the years have been
re-encountered on multiple occasions-- further north. Anyone following
Humnet (list for hummer gardeners as well as hummer lovers in the
southeastern US) should remember Rufous in the northeast that were
assumed dead but turned up again in other locations over the years....

And we have documented hummers (again Rufous and Calliopes) existing
away from feeders before, during and after very cold weather in the
Carolinas. Since we know that hummers, regardless of species, are
insectivorous, we cannot assume that feeders are going to keep them
here. Unless cover and the associated insect fauna are eliminated, the
birds will linger or stay in our area. Maintaining feeders is hardly
affecting their behavior.

Even Ruby-throateds, who are no where near as hardy, can and do endure
colder weather along the Coast each winter. We know they have been here
during the cooler moths in the Carolinabirds for decades now. Inland, I
suspect that having access to a feeder is more beneficial than it is for
coastal birds. Extreme cold and frozen precipitation is unusual along
the coastline-- and, as has been illustrated, it is bad news for even
larger species. In winters with significant cold, individuals have
disappeared (few if any have been confirmed dead)and we know that that
they may move southeast (remember my re-encounter with a Hyde Co.
Ruby-throated later in Carteret Co.).

No one can assume the demise of any of these birds-- unless a body is
found. Although this has happened in a few cases during the last week,
others have simply made assumptions. Please keep in mind that some male
Rufous are now in migratory mode so are moving on regardless of the
weather.

Lengthy cold weather events such as the one we just experienced are, of
course, quite unusual. So, even if some individuals may succumb to
conditions should they not find enough protein, I would not expect mass
mortality. Especially with access to sugar water--- not a bad thing...

Susan Campbell
Research Affiliate, NCMNS
Southern Pines, NC
 
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