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Bald Eagles Re-Use Same Nest -- Sometimes.

Bald Eagle Biology

Do Bald Eagles Reuse the Same Nest Year After Year?

The answer is commonly yes but the eagle territory often houses two or three alternative nests.  I use the word ‘territory’ here because this concept is really more important to eagles than the specific nest.  A breeding territory for eagles only houses a single active nest each year. On the other hand this territory may contain several nests that are alternatively used.

Most active eagle territories support a single nest that is used year after year.  So why do some  territories supports alternative nests and others don’t.  Good question and no single answer is likely applicable to all circumstances.  While a good solid undisturbed 600 year old conifer may support or have supported an eagles nest for 100 or even 200 or more years, most nests don’t last that long.  And certainly the breeding pair of eagles don’t last that long.  It is believed that eagles can live 50 or more years.  Most don’t.   While many conifer trees can live several hundred years most don’t and most deciduous trees live under 100 years. 

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Age of a Bald Eagle Nest

Bald Eagle Biology

Bald Eagle Nest: Probably pushing 100 years old -- PLUS!

Between 1963 and 1967 a bald eagle nest in my Barkley Sound Vancouver Island study area was annually used and produced 1 or 2 young each year. This leaning cedar tree was probably in excess of 300 years of age. The nest was very old and worn from many years of constant use. I had climbed to the nest in the 1960's and my notes state it was a very old nest, “well weathered and lived in”, size, 6 feet 2 inches across and about 2.5 feet deep. The nest had probably been occupied the previous 30 - 50 years.

This nest was one of 136 occupied territories in that part of Barkley Sound that I studied.


Another Visit to Same Nest  in 2003

In July of 2003 my wife, daughter and I were kayaking in Barkley Sound and, as we rounded the southern end of this same Island, I stated how in the early days my favorite nest was suspended over the water in a leaning cedar tree. We rounded the bend and there was the same leaning cedar – with two large full grown young standing in the nest.

As an update to the above, Barkley Sound was largely logged just prior to the 1950's and by the 1970's was designated part of the West Coast Regional National Park. During my study period in the mid 1960's we never saw more than 1 kayak or canoe party per summer and perhaps 3 to 5 pleasure boats. Commercial salmon trollers and shrimp trawlers were constantly working the Imperial Eagle Channel. Today the adjacent area houses numerous trailer parks and campsites, boat launch ramps and an incredible armada of kayaks, canoes and pleasure boats. And the area seemed to have as many bald eagles as it did 40 years ago. Not all is lost.

A question comes to mind: Will a tree sustain an eagle's nest for two or three hundred years? Certainly the trees can live twice that long. And how many different adult eagles nested in this single location? 


David Hancock

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International Bald Eagle Nest Record Scheme

Bald Eagle Biology

Bald Eagle Nesting Season Underway – We Need Eagle Nest Watchers.

National Request: While I started out my studies in the Northwest several decades ago and really started to get “Eagle Watchers” – people keeping a watch on the local Vancouver area eagle nests – I now am expanding this “Eagle Watch” program nationwide. Our Live CAMS on bald eagle nests have shown the international nature of eagle enthusiasts to want to contribute to the betterment of eagles.  This is a program of volunteers to help that cause.

The program is simple.
We get people who are concerned about bald eagles to keep track of eagle nests in their area. I realize there are already hundreds of you out there. In my area these devote “Eagle Watchers” have been my best suppliers of information about disturbances around the eagle nests. If one of them saw any threat to "their" nest they called me or local authorities IMMEDIATELY! . Many of these same observers are also my best source of data on number of chicks fledged etc.

Now I want to expand this study in several ways.

1) Get a bevy of Eagle Watchers around the country – in every State & Province. Each to be watching one or more nests and reporting on it.

...cont ..

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How to Set Up a Bald Eagle Census

Bald Eagle Biology

Guide Lines for Establishing a Meaningful Wildlife Count:

1. SET OBJECTIVES

The objective for most counts by naturalist groups is to show:

----- Regional changes in the species numbers over years

----- Seldom are we measuring absolute changes in numbers since there
are usually so many variables that are not practically controlled.

-----

2. BE CONSISTENT:

----- Choose confined period (1 week of May??) each year.

----- Keep the counting stations at consistent locations.

----- Keep the counting techniques, time allotted etc. consistent.

----- Keep the same or as many of the same counters each year.

For more detailed instructions see more: ...........
 

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To Feed or Not to Feed Eagles

Bald Eagle Biology

To Feed or Not To Feed Eagles?  A Review
=============================================

Many conservation organizations and governments not just support feeding wildlife but depend upon the funds raised from selling bird food or the taxes generated.  Feeding wild birds is big business.  It is also a practical business.   Undoubtedly the only way our degraded city or urban habitats,  with their natural grasses, shrubs and trees  replaced by roads,  houses and gardens,  can house any wildlife, and particularly birds,  is for humans to replace some of the items we have destroyed.  The artificial garden plants don't always produce the same seeds, pollens or insects that feed our native birds.   

The  human supplemental feeding of these birds with bought seeds, suet and honey-water  etc. provides many native species with the key items destroyed and missing in the urban environment  -- the food items that were removed by human development.  Of course some feeders also attract sharp-shinned and coopers hawks, merlins and peregrine falcons, assisting other elements  in the food chain indirectly.

That feeding wildlife is a generally accepted principle and   ..........

 

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