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Irruptions, What Are They?
December 03, 2018

(A December Mourning Dove.)

We enter the last month of 2018.

Where does the time go?

Busy as usual.

We dropped off the special needs van for its  six month checkup this morning.

Tuesday we go to Mary Free Bed to visit with Yolanda's dietitian, to check on any progress we may have with her losing weight.

Throw in day to day stuff, and that is where the times goes.

Some weeks more than others.

November ended more than 5 degrees below average, and only 9% sunshine.

The lack of sunshine was 11% lower than the average of 205 for November.

A challenging month for sure.

We did manage a bit of a Thunderstorm on the night of December 1st.

Not unheard of, but rare none the less.

The local woods this time of year sure looks lonely.)

The start of a new month is always a good time to give your feeders and water sources a good cleaning.

If winter weather doesn't allow for you to get in a good and deep clean and sanitize, you can always go the quick and temporary route.

Rubbing alcohol in a spray bottle works wonders.

You can spray the feeders and allow for them to air dry.

Rubbing alcohol drys without leaving anything harmful behind.

Ideally, a deep clean with a couple ounces of chlorine bleach, in a gallon of water gets everything.

Where possible, toss and rake old and moldy seed.

Moldy seeds carry all sorts of bacteria that can sicken and kill your birds.

It has been several years since I have written on this topic.

Must be all the Red-breasted nuthatches I see this year.




An irruption is a dramatic, irregular migration of large numbers of birds to areas where they aren’t typically found.

Possibly at a great distance from their normal ranges.

While one or two vagrant birds of northern species may appear at southern feeders in any year, an irruption is characterized by large numbers of unexpected birds.

Depending on the species, irruptions may occur in cycles from 2-10 or even 15 years, or they may be much more unpredictable.

The fundamental difference lies in the prefix.

Irruption, starts with a variant of Latin 'in', and means bursting or breaking in.

Eruption, starts with a variant of Latin 'ex', and means bursting or breaking out (think volcano).

They're not interchangeable words.

Every winter across North America, bird watchers anxiously await the possible incursion of birds that don't normally winter in their areas.

These periodic bird irruptions (not eruptions) add a dramatic level of excitement to winter birding.

For new readers and novice backyard birders, irruptions occur when one or more species of bird(s) all of a sudden appear out of no where.

(Pine Siskin).

If you are new to birding, it is a first time thing and many spot birds that are new to them and wonder why they haven't seen them before or where did they come from.

Sometimes harsh winters or the lack of food will cause irruptions, but not always.

Some birds irrupt every other year, while another species may not irrupt for 10 to 15 years.

The birds most commonly associated with these winter irruptions are the winter finches (Pine Grosbeak, Red Crossbill, White-winged Crossbill, Purple Finch, Pine Siskin, Common Redpoll, and Evening Grosbeak).

Don't forget the Snowy Owl as well.

Other species will also shift from their typical wintering grounds into other areas.

For example, Bohemian Waxwing, Black-capped Chickadee, Clark's Nutcracker and Varied Thrush will stage periodic winter irruptions.

Golden-crowned and Ruby-crowned kinglets will irrupt from time to time.

I have never seen kinglets in great numbers, but I will have them visit certain years.

The arrival of winter finches to your backyard does not necessarily indicate a harsh winter ahead.

It is generally believed that irruptions are driven by a lack of food on the normal wintering grounds.

For example, Common Redpolls feed primarily on the catkins produced by birch and alder trees.

(Purple Finch).

When catkin production is low, Common Redpolls leave these areas and irrupt into areas where food is more plentiful.

Common Redpoll irruptions can be extensive, ranging as far south as the Middle Atlantic States or central Kansas.

On major years of irruption, you may see too many redpolls to count,

It was this way a couple of years ago for me and for much of the upper Midwest and northeast United States.

It was the same winter two years ago that Snowy owls were spotted in several locations hundreds of miles south of their normal range.

Some years, you may see a few Common redpolls.

Still, most years you wont see a thing unless you live in Common redpoll country.

Another member of the finch family are Pine siskins.

Siskins are distributed across much of Canada and at higher elevations in the western portions of the United States and small populations in the Appalachian Mountains.

Irruptions of Pine Siskins is biennial, meaning this species irrupts every other year.

What is interesting in the Western regions is this.

They seem to take turns irrupting east of the Rockies one time and west of the Mountains the following irruptive year.

Yet, in the east they are almost like clockwork.

Last year I was Purple finch-less, I'm hoping for better results this winter.

Then there is good OLE reliable, the Red-Breasted-Nuthatch.

Red-breasted nuthatches are one of the most reliable birds to irrupt.

In my Southwest Michigan yard, several appear every two years and this is the year.

The little nuthatches arrived about a month ago, and I have never been blessed with this many of the tiny birds.

If they would stay year round, they would be in my top five favorites, as they are a very friendly bird, much like chickadees.

Rather easy to get them to hand feed as well.

It is a rare winter when no species of bird is irrupting somewhere in North America.

An event could be geographically limited; for example, Varied Thrushes (native to the Pacific Northwest) occasionally undergo greater dispersion on their typical winter range in the Pacific Northwest.

On the other hand, an event could be as dramatic as the simultaneous irruption of several species into one area.

On rare occasions  Red and White-winged crossbills, Common Redpolls, Evening Grosbeaks, and Pine Grosbeaks staged a massive "super-flight" into a region.

Redpolls irrupt more often in some regions, I haven't seen them for 15 years.

Scientists would like to better understand how and why these irruptions occur.

It is believed to be food related?

What other reasons call for irruptions?

You can even become an volunteer or amateur scientist.

By monitoring birds in your backyard or your favorite birding areas and reporting irrupting species over the Internet to the Cornell Lab of Ornithology, Irruptive Bird Survey at Bird Source.

By doing so, you can help answer some of these questions:

What bird species and how many individuals are irrupting?

When does the irruption begin and how long does it last?

To what geographical extent is the irruption?

What influence does food availability have in areas where birds have irrupted?

Be on the look-out for irrupting species (and note wild food availability in your locality).

Well, it is time to fly for now.

Before I go, here is your positive thought for the week.

God Bless.

"No man or woman of the humblest sort can really be strong, gentle and good, without the world being better for it, without somebody being helped and comforted by the very existence of that goodness".

Phillips Brooks (1835-1893) American Bishop

Think about it my friend.

In this day and age where we are taught me,me,me,..............

It is really about giving, helping and sharing with others and those in need.

"Be kind and compassionate to one another, forgiving each other, just as in Christ God forgave you".

Ephesians 4:32 

“But love your enemies, do good to them, and lend to them without expecting to get anything back. Then your reward will be great, and you will be sons of the Most High, because he is kind to the ungrateful and wicked.”

Luke 6:35

"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.

A Blessed week to you .

Your friend indeed,

Ron Patterson

PS. If you enjoy these letters, please forward them to friends, family and co-workers.

Better yet, have them sign up so they can receive their own letters.

Gardening For Wildlife.

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