What about them crows!

[half-dutch]

There must be tens of thousands of crows that winter in the Twin Cities! All winter long I have watched the almost endless streamers and pods moving east to night time roost as I came home from work in Hopkins to Minneapolis. Always all in the same direction; I am guessing to night roost along the Mississippi, although I have never tracked that down. Wherever it is it must be huge.

About a week ago that changed. There were break away pods heading back and NW and then circling back around, all along Lake Street as I came through the Uptown and east. Crows are always noisy, but the noise level picked up dramatically. Pods would break away and others would seem to go after them to bring them back in line. I will say what I saw what looked to be intimidating behavior but never any actual birds attacking other birds. It looked for all the world like screaming matches.

The last few days there has been a huge group stopping in the trees just a block south of my house instead of the former constant stream east, and the racket they made yesterday was audible inside my house a block away. It must have been deafening in the houses under those trees. There must have been how many hundreds, I couldn't begin to guess. An occasional group of dozens would break away, and then pull up a block or two out when the mass didn't follow. Another group would trail out once they pulled up and seem to bring them back. I did not see how that all turned out but I doubt that the group roosted there. It seemed more than anything like they couldn't come to a group decision on where to roost with every bird trying to shout every other one down.

Is this how the huge winter crow roosts break up as winter turns to spring and they start to sort out family groups for nesting? I am aware that very often last year's nestlings will help their parents raise a current years hatch rather than nest out on their own. For as aggressive as they are they are also remarkably social birds. This winter crow thing though looks more like a chaos than how organized it must normally be, especially at this time of the year, if this is how the big winter roosts actually break up. Everything crow at this time of the year seems to be happening at maximum volume, too.

These are very interesting birds to watch.

[PurpleFloyd]

I know the population in SC Minn is booming. As I drive to Mankato every day the numbers are several birds per mile along Hwy 15 and 60.

I know Mankato had a band of hundreds of them that would be in the air over the Minnesota river every morning when I went through and on a recent drive from Mankato to Forest City Iowa I saw 3 deer 0 Pheasants and probably 150 crows if that tells you anything about their population density.

[trolloni]

Send em down here our season ends the 28th,i would love to help ya thin the herd!

[smnduck]

Between 5,000 and 10,000 roost in the Mankato river bottom area.

[bobbymalone]

I saw a carp ton (thousands) of them roosting in the trees just on the other side of the noise blocker wall for a half mile stretch on 35W in south mpls. this was right around dark a couple days ago.

If that was happening in my yard, I would be hailed as the neighborhood hero as the minneapolis police confiscated thousands of illegal bottle rockets and issued the citation.

[half-dutch]

I live in that section of south Mpls. The roosting pattern has changed in the past couple of weeks, now some thousands are staging every evening for something within a few blocks of my house. My best guess is that the big winter nighttime roosts are starting to break up ahead of moving out back to nesting areas. I find it amazing that such large and aggressive birds seem to be working out relatively complex social arrangements in such numbers and I have yet to see an actual fight, although I have seen some chases.

From what I understand these are probably not the crows that will nest locally, but mainly are those who winter here from nesting areas outside the Metro primarily to the north, although I do not know whether our summer crows actually winter here or not. Generally there is a shift of all parts of a population to the south for wintering, but we have resident ducks and geese that used to move out but no longer do; so crows may also be sticking around all year, now that absolute winter lows have moderated a bit, which is the dramatic effect of global warming in our area.

The harshest limiting factors have warmed some 5 degrees in the past few decades from what used to be very stable harsher conditions. That is not apparent from snowfall amounts or the number of days below freezing, although those have also decreased. It is the kill point that has moderated at the extreme that is most dramatic.

There certainly has been a dramatic increase in the numbers of formerly more southerly migrating birds that overwinter here over the past few decades.