island conservation blue-footed booby

Why So Blue? Evolution and The Blue-footed Booby

Have you ever wondered why the Blue-footed Booby has blue feet? Science has the answers.

What’s in a name? The Blue-footed Booby’s name can tell you a lot about the unique birds. The species is known for its striking turquoise-colored feet, and the name Booby is believed to derive from the Spanish word “Bobo” which means “clown” or “stupid” and refers to the bird’s peculiar waddle.

Blue-footed Boobies have widespread populations throughout the tropics and subtropics of the Eastern Pacific. Large populations give researchers ample opportunity to study the species very closely and learn all about the birds’ mating, parental, and feeding habits. David J. Anderson of Wake Forest University explained:

They’re super fascinating animals and such a good research model…they let you move among them without minding too much. You try to do that with a continental bird or mammal—forget about it. But with these guys you see it all.

island conservation blue-footed booby

Blue-footed Booby in the Galápagos. Credit: Island Conservation

The birds’ tolerance for humans has allowed researchers to deeply explore the world of the Blue-footed Boobies.  One big question researchers have worked to uncover is: why do Blue-footed Boobies have blue feet?

Researchers have identified two main factors in the blue-ness of the birds’ feet – one is an internal mechanism and the other is from their food. Juvenile Blue-footed Booby feet are only slightly blue; this is because of an alignment of proteins in the skin that results in a purplish-blue hue.

In the bird community, the bluer the feet the better. Both males and females are selective about the blueness of their prospective mates’ feet, but the internal proteins are not enough. The added pigment comes from their food. Boobies are seabirds that preferentially feed on schooling fish such as sardines. They extract bright yellow pigments from carotenoids in fish, a process which causes their feet to display a turquoise color. Evolutionarily the blue feet show that the bird is healthier  than a less-blue counterpart.

The color of the Blue-footed Boobies feet is only a fraction of the discoveries scientists have made and there are plenty more to come from these unique animals.

Featured photo: Blue-footed Booby. Credit: Emily
Read more about Blue-footed Booby research in the New York Times

About Emily Heber

Emily is a recent graduate from UC Santa Barbara with a BS in Zoology. As a student, she discovered that she had a passion for the conservation of endangered species and their ecosystems. Her background in informal education has allowed her the opportunity to share her passion for animals with others, something she seeks to continue doing while working with the communication team. In her spare time, Emily enjoys exploring the amazing hiking trails found in Santa Cruz and tries to SCUBA dive whenever possible. Emily is excited to join the Island Conservation team and to help share the amazing work that is being done here.

View All Posts

Follow Island Conservation on Social Media

[ism-social-followers list='fb,tw,li,youtube,instagram' template='ism_template_sf_1' list_align='horizontal' display_counts='false' display_full_name='true' box_align='center' ]

[indeed-social-media sm_list='fb,tw,li,rd' sm_template='ism_template_8' sm_list_align='horizontal' sm_display_counts='false' sm_display_full_name='false' box_align='center' print_total_shares=1 tc_position='before' display_tc_label=1 tc_theme='dark' ]

[ism-social-followers list='fb,tw,li,youtube,instagram' template='ism_template_sf_1' list_align='horizontal' display_counts='false' display_full_name='true' box_align='center' ]

Midway Atoll conservation




%d bloggers like this: