Our pine forests contain a keystone species that has a hand in increasing the number of other species around it.
The cavities that Red-cockaded Woodpeckers make are used by over 35 other species – everything from mammals to reptiles, and even amphibians – over the lifetime of the cavity.
It turns out, these cavities may get better with age.
Read more about Red-cockaded Woodpeckers in the Red Hills
First, what makes the Red-cockaded Woodpecker’s cavity so special is that they are only made in living, mature pine trees.
While we have six other woodpeckers frequent our forests, the Red-cockaded is the only one to make cavities in living pines, and for good reason.
Living trees are incredibly hard. The sapwood of these trees is so dense that even a specialist like the Red-cockaded will end up spending months or years to make a single cavity. Other woodpeckers use dead trees, a much softer substrate for their homes.
This extra effort to make a cavity in a live tree is well worth the effort however.
The Red-cockaded Woodpecker’s cavities will last for decades whereas other woodpeckers’ cavities in dead trees would be lucky to last three years before the cavity breaks apart or the tree topples over.
More than 35 different species will use the cavity of a Red-Cockaded Woodpecker over the lifespan of the space.
The ability to make cavities in living pines is especially lucrative in a long-lived forest such as one domniated by longleaf pine.
Longleaf pine is unique for southern pines in that it is more likely to be killed by lightning instead of old age.
This means the trees in the forest could be hundreds of years old and, until or even if that unlucky strike from the clouds occurs, the tree would keep living, leaving the other woodpecker species waiting for a home to become available.
The Red-cockaded woodpecker can make a new cavity about every other year or so in living pines.
But even their cavities in living pines are prone to weathering over time. Once the cavity is decayed and larger than 1.5 inches in diameter, the Red-cockaded woodpeckers will abandon it for a newer, fresher home.
This vacancy breeds opportunity for many other critters.
At first, other species such as White-breasted Nuthatches and Tufted Titmice will use the Woodpecker’s cavity as their nesting sites.
Species of mammals such as mice and flying squirrels can also use the Red-cockaded Woodpecker’s cavities for nests, food caches, or even just temporary places to rest.
A few years after the woodpecker abandons its old home, larger woodpeckers can finally use it for their roosts.
The Red-bellied Woodpecker and Red-headed Woodpecker can carve the old Red-cockaded Woodpecker’s cavities to fit their bulkier bodies and use them for roosting and nesting as well.
Other critters such as tree frogs and even snakes will use the old cavities as well making use of the well-insulated tree for their cold bodies.
Fast-forward a few decades and what was once a small hole in a tree could become a cavity anywhere from the size of a baseball or even a football.
When the cavity is this large, fox squirrels and Wood Ducks can use them.
Since the Red-cockaded Woodpecker is making cavities where there wouldn’t be one otherwise, it makes this bird a keystone species for the pinelands.
A grey rat snake has taken up residency in a manmade Red-cockaded Woodpecker cavity. Snakes are among more than 35 species that may use the cavities over their lifespan.
Having these birds in the forest enriches the overall diversity and abundance of animals.
A decade after the Red-cockaded Woodpecker was reintroduced on Tall Timbers property in 2006, the effect was clear.
The abundance of other cavity nesting species such as Great-crested Flycatchers, White-breasted Nuthatch, Red-headed Woodpeckers and Northern Flickers had all increased on the property.
That’s why it has been so important to return the Red-cockaded Woodpecker back to the pinelands wherever possible.
Not just because they have been endangered since the 1970’s, but because their cavities harbor many other benefits for the forest as well.
As biologists bring back the species to the pinewoods, the birds can continue to make their cavities which will one day serve as the homes for the many other species that depend on them.
