The Case of Red and Woodpeckers

Have you ever noticed that the woodpeckers visiting your yard have red on their bodies? Specifically, their heads. Of course, there is the Red-Headed Woodpecker. However, Red-Bellied Woodpeckers and Pileated Woodpeckers also have red on their heads, as do the male Downy and Hairy Woodpeckers. 

Is there a reason for this?

Sadly, it isn't fully understood why so many woodpeckers exhibit red markings on their heads. It is understood, however, that  a lot of these species face similar environments and pressures, and are therefore likely to evolve similar strategies and even feather patterns. Some studies have shown that although for certain species the red-head feature is sexually dimorphic, and therefore differentiates males from females, the brightness of a red cap can indicate body condition. An interesting theory. 

Convergent evolution put simply is when species from different time periods separately evolve similar traits. 

Let's cover some of the Ontario's woodpeckers, including how to distinguish their red features from other similar birds and whether their red features differ by sex:

1. Pileated Woodpecker 

Male Pileated Woodpecker. Photo by Shayna Hartley. 

Both male and females of the species have a red head cap, only males have the additional red line along their mandible or jaw. 

Female Pileated Woodpecker, no red on the mandible. Photo by Shayna Hartley. 

2. Red-Headed Woodpecker 

Red-headed Woodpecker. Photo by Kristen Martyn. 

Both male and female Red-headed woodpeckers look identical, and do not have sexually dimorphic traits. 

3. Red-Bellied Woodpecker 

Both male and female Red-Bellied Woodpeckers have red on/near their head. However, there is variation by sex. Females have red napes and the small bit of red above their bill, whereas males have a full red nape and head cap. Below is a good comparison of a male and female on the same feeder, facing the same direction that accents the difference. 

Female Red-Bellied Woodpecker, photo by Kristen Martyn. 

Male Red-Bellied Woodpecker, photo by Kristen Martyn. 

People commonly get confused as to why this species is called Red-Bellied woodpeckers - they have red heads and we often can't see any red belly. As you can see above, only the males have a fully red head, yet they all have red bellies, they can just be hard to spot. The red belly feathers are often obscured by surrounding feathers, which makes this a difficult feature to view.   To learn more about this incredible species, read our former Species Spotlight blog all about them, here. 

Here you can see the red belly that their name refers to. Photo by Heather Kerrison. 

4. Downy Woodpecker

Downy Woodpeckers are also easily distinguished by sex, as only the males have a red nape. Below is a picture that showcases a male and female on the same feeder, with the red marking allowing us to easily tell them apart. 

Side by side comparison of Male and Female Downy Woodpeckers. Photo by Kristen Martyn. 

5. Hairy Woodpecker 

Hairy Woodpeckers present very similarly to Downy Woodpeckers. The most noticeable difference is their size, with Hairy Woodpeckers being noticeably larger. Hairy Woodpeckers are also easily identifiable by sex, for the same reason that Downy's are: the males have a red nape and females do not. 

Male Hairy Woodpecker. Photo by Kristen Martyn. 

Female Hairy Woodpecker. Photo by Kristen Martyn. 

I apologize for not having all of the answers when it comes to why so many woodpecker species have red on their heads. Something that is endlessly fascinating about nature and wildlife is how much we still have to learn and understand. 

To attract a wide variety of woodpeckers to your yard and practice your ID skills, make sure to offer:

• SuperSuet
• Bark Butter
• Peanuts
• Mealworms 
• Seed Cylinders 

Hopefully I have left you with more questions than answers, I encourage you to be endlessly curious about our natural world. 

Warmly, 

Heather