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Gardening For Wildlife #47 Irruptive birds
December 17, 2007

A blessed week to you.

Winter has gripped much of America.

Ice storms in the Mid-West, Some much needed rain in parts of the South and a snow storm.

Though my part of Southwest Michigan has missed most of the back to back ice storms, we managed to get a good blast from this past weekend's snow storm.

Our prayers go out to families still without power and other misfortunes from the weather.

Who know's, we might have a White Christmas yet.

The birds were very busy before the storm.

I keep saying this.............................

Birds know when a storm is on the way.

My little Red-breasted-nuthatch has given me some great joy this past week.

A few times he flew right up to me as soon as I walked out the door onto the deck.

He would snatch, fly to a nearby Spruce, stash his peanut piece and come right back for more.

What a treat that was for me.

Karen got in on the action too.

Yolanda chuckles over the sight. I told her I will bundle her up one day and let her feed the bird.

His lady friend still is a bit shy, but I managed to get another male to take from my hand near the peanut feeder.

Birds are everywhere, including a fly through from a Cooper's hawk now and then.

The turkeys have become almost regulars right now.

I don't know if that is good or bad, as they can tear up a scatter mulch and tear up a flower bed right before your eyes.

This past week I noticed for the first time in a few years some Common redpolls at my thistle sock.

Curious as I am, I decided to do a bit of research and discovered that this is an irruptive year not just for Red-breasted nuthatches, but many species of Boreal forest birds.

Especially the finch family.

Just what is irruption and why does it occur?

Irruption is when a mass migration occurs from a typically non migratory bird.

Usually harsh weather or a lack of food will cause an irruptive year.

For some birds, there is no rhyme or reason for irruptive periods or years.

It just happens.

Pine siskins for example irrupt every other year, yet irruptions are on opposite years from Western Siskins and Eastern birds of the species.


It just happens.

Author and naturalist Henry David Thoreau paused one cold December day in 1855 to ponder in a bleak Massachusetts swamp.

"The incredible phenomenon of small birds in winter - that ere long, amid the cold powdery snow, as if it were a fruit of the season, will come twittering a flock of delicate crimson-tinged birds, redpolls, to sport and feed on the seeds and buds now just ripe for them on the sunny side of a wood."

Thoreau also knew that some winters the redpolls did not come, and their irregular appearances puzzled him.

After he watched a flock foraging in white birches along the Concord River, picking seeds out of catkins while hanging head-first from treetop twigs, he wrote,

"Common as they are now, and were winter before last, I saw none last winter."

Redpolls are no less erratic now than they were then.

It can be several years between irruption for these birds of Northern Canada's Boreal forests.

Irruption, the phenomenon typically involves one or more of North America's "big eight" boreal seed-eaters: the common redpoll, pine siskin, purple finch, evening grosbeak, pine grosbeak, red crossbill, white-winged crossbill and red-breasted nuthatch.

To that list add the black-capped chickadee, whose large flights out of the North Country are often overlooked because everybody sees chickadees every day.

This may explain why I have more chickadees this year. I have seen 10 and 12 at a time.

There is no set pattern for irruptive birds.

Migrants have predictable patterns, with irruptive species, there is no predictable time table or for most irruptions, what year it will occur.

To some extent, Red-breasted nuthatches have a predictable cycle, but on those years I will get a couple at my backyard.

This fall and early winter there are several nuthatches and I am thrilled.

Others are reporting Pine and Evening grosbeaks where they haven't been seen for years.

There is reason, but not rhyme, to the travels of boreal seed-eaters.

Contrary to popular belief, hard winters do not drive the birds south.

Although the red-breasted nuthatch and various finches consume some insect life during summer months, they feed largely on conifer cones or the catkins and seeds of deciduous trees, all of which are high off the ground.

Heavy snow isn't a problem - nor is glacial cold.

Redpolls can survive at 60 degrees below zero if they have plenty of food,"

Pretty Amazing huh?

There have been several indications that this is indeed a major irruptive year.

According to Ontario Field Ornithologists, Most coniferous and deciduous trees have very poor seed crops in Saskatchewan, much of Ontario and western Quebec.

Severe drought conditions throughout much of Michigan (esp. The U.P.) contribute to these seed failures and birds have moved further South.

This forces many species to move out of these areas in search of adequate food sources.

Also of interest in irruptive birds,

Look for northern Owls (Great Gray Owls, Northern Hawk Owls and Boreal Owls)

With poor seed crops, voles and other important food sources for owls may crash

If this happens, Southern Canada and the Northern states may begin to see these owls of the boreal forests.

How far South will these irruptions occur?

No one really knows.

If you are fortunate enough to have some rare or strange visitors to your yard, you may want to report it to your Local Audubon chapter.

More importantly, is to enjoy the experience.

It may not happen for another 10 or more years.


That's it for now.

If all goes well, the Christmas letter will come out later this week (hopefully Thursday), instead of next week.

So many of you will be gone and I know many of you read it at work.

Besides, I need some time off too :-D

Christmas is a very special day and time of year.

When you are out and about, please think of others too.

Give them a break on the road or in the stores.

Always smile and share it freely with others.

Has God blessed you enough to share with others?

Then give with a thankful heart.

Keep your feeders filled and snow free.

Birds need fresh water too.

Keep your baths clean and filled.

Are you new to backyard birding?

Look at bird baths to understand more about water

"Treat the earth well:

It was not given to you by your parents,

It was loaned to you by your children.

We do not inherit the Earth from our

Ancestors, we borrow it from our Children."

Ancient Indian Proverb

Your friend indeed,

Ron Patterson

PS: Feel free to forward this to friends and family or send them to so they can register to recieve their free copies.

Gardening For Wildlife.

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