To Help, or Not to Help, ask red-cockaded wodpeckers

“There! I see one!” one of my fellow classmates excitedly exclaimed. I followed the trail of her finger and lifted my binoculars to my eyes just in time to see a red-cockaded woodpecker (Picoides borealis) pecking on a nearby tree. It was early in the morning, around 8 am, and we were at the W. Goodrich Jones State Forest near Conroe, Texas on our second bird watching field trip. The weather was beautiful and it was a perfect day for bird watching. We only observed one woodpecker, although there were probably more in the area because we could hear additional calls. Red-cockaded woodpeckers are medium sized woodpeckers with a black back with white spots and a primarily white head. The one we saw was a male, indicated by a red patch on his head. We were about twenty feet away, yet that was close enough to hear the bird peck on the bark in search of bugs and other food inside. We were fortunate that the bird remained perched on the tree for a few minutes. It alternated calling and pecking in a smooth rhythm before flying away just as quickly as it had arrived. We continued on the trail, but as the day got later, the calls lessened and the woodpecker was nowhere to be found.

My first encounter with a red-cockaded woodpecker was brief, but fascinating. I’ve always felt some sort of a connection to woodpeckers. I don’t know why, but I think it has something to do with them being betrayed as cartoons such as Woody the Woodpecker! All cartoons aside, I wanted to learn more about this cute tricolored woodpecker so I searched through the literature found on Google Scholar. I found tons of cool articles about red-cockaded woodpecker behavior, and I was shocked at the amount of research performed on this particular species.

The first paper I found was written in 1986 by Michael Lennartz, Robert Hooper and Richard Harlow. In their paper, they discuss the phenomenon of avian cooperative breeding in red-cockaded woodpeckers observed in South Carolina. Sounds complicated huh? Basically, in a cooperative breeding system, some individuals in a population do not breed so that they instead help other birds raise their young. Nearly 150 bird species practice this technique, but the sheer numbers do no explain why this practice occurs. Lennartz and company argue that these woodpeckers decide to engage in this cooperative behavior because of the increase in fitness that results from it. Nesting cavities take a long time to form and can be hard to find, which limits opportunities to breed. Also, breeding and raising young can be strenuous and physically draining for the bird. So instead, brothers opt out of the breeding process to instead take care of their siblings. But keep in mind that is just the beginning of the benefits! In 2002, Memuna Khan and Jefferey Walters performed a study in North Carolina looking at the beneficial role cooperative breeding has on red-cockaded woodpecker population size. They found that in addition to the energy advantages gained by not breeding, cooperative breeding also lessens predation, lightens the foraging load and also increases the chances that a closely related sibling will survive.

So why all the fuss about red-cockaded woodpeckers? As I mentioned before there are many other birds that exhibit the same behavior. Unfortunately, red-cockaded woodpeckers get so much attention because they are endangered, so many scientists are interested in how cooperative breeding behavior might help increase their numbers in the wild. In 1990, Todd Engstrom and Gregory Evans assessed how hurricane damage and habitat removal impacted red-cockaded woodpecker population sizes in Georgia. They found that since red-cockaded woodpeckers like building cavities in old diseased trees, this left them increasing susceptible to natural disturbances since those trees are the easiest to uproot and break during a storm. As if that were not enough, the birds also have to compete with other animals that might also use the cavity when extensive damage to forest areas occurs. Additionally, in 2002 Karin Schiegg, Jeffrey Walter, and Jeffrey Priddy found that when populations of red-cockaded woodpeckers reduce in size, their dispersal habitats can change. Basically, woodpeckers have a harder time finding mates and acquiring breeding status when the populations are spread out over great distances. This struggle to find a mate (these woodpeckers are monogamous!) can cause rapid population declines in an already fragile group.

All this conservation research made me think, what’s Texas doing to help out or friendly woodpecker? Well, lots of things to be honest. In 1995, Richard Conner, Craig Rudolph, and Larry Bonner studied red-cockaded woodpecker population trends in four East Texas National forests. Their goal was to analyze the effectiveness of aggressive management programs aimed at increasing the number of woodpeckers here in the lone star state. They found that placing artificial cavities and moving existing populations of woodpeckers was an effective way to stabilize and even increase the number of woodpeckers in the forests.

With all this new knowledge about red-cockaded woodpeckers, I now feel even more appreciative for having seen one in real life. Besides, it’s not every day that one gets to see an endangered species outside of the zoo! So I end this blog with a question: to help, or not to help? Should red-cockaded woodpeckers continue to sacrifice their own reproductive abilities to help their siblings? Regardless of the answer one thing is for sure, we should help them, to help themselves.

Here are some of the references I used in this entry:

Conner, R. N., Rudolph, D.C., Bonner, L.H. 1995. Red-Cockaded Woodpecker Population Trends and Management on Texas National Forests. Journal of Field Ornithology. 66:140-151.

This paper discusses the management of red-cockaded woodpecker populations in Texas National parks.

Engstrom, R. T. and Evans, G. W. 1990. Hurricane Damage to Red-Cockaded Woodpecker (Picoides borealis) Cavity Trees. The Auk. 107:608-610.

This paper discusses the natural loss of Red-cockaded woodpecker habitat due to natural disasters.

Khan, M. Z. and Walters, J. R. 2002. Effects of Helpers on Breeder Survival in the Red-Cockaded Woodpecker (Picoides borealis). Behavioral Ecology and Sociobiology. 51:336-344.

This paper discusses how helpers are beneficial to the survival of breeders and how the species gains indirect fitness benefits.

Lennartz, M. R., Hooper, R. G., Harlow, R. F. 1987. Sociality and cooperative breeding of red-cockaded woodpeckers, Picoides borealis.  Behavioral Ecology and Sociobiology. 20:11-88.

Doi: 10.1007/BF00572629

This paper discusses cooperative breeding in red-cockaded woodpeckers.

Schiegg, K., Walters, J. R., Priddy, J. A. 2002. The consequences of disrupted dispersal in fragmented red-cockaded woodpecker Picoides borealis populations. Journal of Animal Ecology. 71:710-721.

Doi: 10.1046/j.1365-2656.2002.00637.x

This paper discusses how population fragmentation can impact population dynamics of the red-cockaded woodpecker.

A red-cockaded woodpecker eating a bug. Photograph courtesy of U.S. gov’t (public domain)

Banded baby red-cockaded woodpeckers. Photograph courtesy of U.S. gov’t (public domain)

This graph is taken from the Schiegg article and illustrates the frequency of each type of role male red-cockaded woodpeckers play in a population of the given sizes. Most males are breeders, and very few males are dispersing, regardless of population size.

This graph taken from the Kahn article illustrates how helpers ease the burden of raising young for the breeders.

The above image is the range map for the red-cockaded woodpecker. The birds only reside in Southeast North America (Photo from allaboutbirds.org).

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