Woodpeckers point to a solution for safety-minded arborists

Sometimes an answer to a contentious problem is at eye level but we cannot see it.  Old beliefs and habits have a way of blinding us.   Recently woodpeckers nesting in Orange County’s urban parks, under the watchful eye of volunteers of the Cavity Conservation Initiative, have revealed a welcome solution to a growing problem for arborists, land managers and wildlife advocates.   Here it is.  How to ensure public safety while leaving dead trees for birds that nest in them.

The shortest and surest answer is to make a 5′ totem pole out of the dying tree.  That’s what woodpeckers are suggesting.  Some now excavate nesting cavities lower than eye-height; 4′ off the ground.  This is surprising even to bird advocates, but the evidence is there.   Not ideal real estate, but when the housing market is bad, the birds seem to be getting less picky.  Read on for the fuller story.

NUWO Peggy Honda

Nuttall’s Woodpeckers nesting five feet off the ground                    By Peggy Honda

Snag at Mason with 2 holes

Two nest sites made in subsequent years.

Currently most dying trees in urban and suburban areas fall to the chain saw and are hauled away.  Risk to people and property, and fear of liability, have understandably been unsurmountable barriers to retain them.  However, the consequence to birds that nest only in dead trees is becoming clear.  Some populations have been declining or disappearing from certain regions stripped of dead trees.  Woodpeckers are critical to many other birds who inherit their abandoned nest sites.  Without dead trees and without woodpeckers to excavate homes in them, about 40 cavity-nesting species in North America would be in jeopardy.

5' stump_1024

One nest site in tree stump less than 6′

Very short snag used by Mountain Bluebird_1024

Multiple cavities in stump in parking lot.

These photos show that a decaying tree trunk or tree stump only 5 feet tall with few or no branches is acceptable to some Southern California’s woodpeckers.   But let’s look beyond tree stumps and totem poles.  Binoculars and cameras show that it’s worth looking at live trees as well.


Nest site in shortened limb on a live tree.


All woodpeckers will use a dead limb just 18″ in length on a live tree.  The limb just needs to be about 6″ in diameter.  The length matters because woodpeckers are not carpenters of small-rooms.  They prefer rooms that look like the inside of a gourd.  Narrow entrances generally lead to deeper, more spacious chambers below.

Volunteers are working to persuade those who make tree management decisions to take a second look at the habitat potential within their power.  They are asking arborists to leave as much of a dead limb and a dying tree as they safely can.  Putting a helpful sign on the tree would educate the public.

Recent scientific study reveals that many birds driven away by the loss of open space and native habitat are finding ways to adapt to urban settings.  The race is on to meet their needs before the impact is irreversible.

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