The TRUE Indicator Bird of Spring

Updated: Apr 12

Many will argue with me for this statement, but American Robins do not indicate spring has arrived. Read on to learn WHY!

A Red-winged Blackbird sits on a sign, singing
Red-winged Blackbird Singing on a Sign

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Birds of Spring

Likely, there is no singular species that would indicate spring has arrived for the entire country. For every state, there are likely multiple species that could be easily argued as the harbinger of longer days and warmer weather. And for a state with an almost seemingly perpetual winter, the Red-winged Blackbird is my nominee. Now, many will argue the Red-winged Blackbird overwinters in Wyoming. Yes, I understand that. BUT! Most Red-winged Blackbirds leave Wyoming and return around mid-March. Disbelief from the peanut gallery? I've got data to back me up.

Also, does anyone still use the phrase peanut gallery? And why do we use it? It was based on the cheap seats in the back/top of the theater, and they ate the cheaper snack, peanuts. But why would that crowd be so critical? Moving on...

Spring Bird Data

Red-winged Blackbird Abundance Data in eBird for Wyoming *
American Robin Abundance Data in eBird for Wyoming *

BOOM! Datum drop. It is like a mic drop, but way nerdier.

Maybe you are struggling to interpret these graphs. If you are, do nay worry a wee little hair on thy head. I will tell you what they mean.

First, let us address abundance. Here is how eBird defines its use of abundance:

"Abundance" is the average number of birds reported on all checklists within a specified date range and region. These data tell us what we might to expect when going out birding on an average day. The checklists used in this calculation include those that didn't report the species, providing a measure of relative abundance or how commonly the bird is reported compared to all other species in the region. For example, when looking at data for New York we see that during the week starting 15 May we can expect to find roughly 1 Yellow Warbler while out birding. In contrast, in the same region during the same week we see that zero Rough-legged Hawks, primarily a winter visitor, can be expected in an average day's birding.

Easy enough, right? Right. Back to the graphs. What these graphs tell us: during winter in Wyoming we can expect to see ~1 American Robin on any given day and are NOT likely to see a Red-winged Blackbird during the average day, with an abundance of ~.1.

However, this is still not my largest point. I want to turn your attention to the CHANGE in abundance from the week of 1/1 to 3/22 (the first full week of spring). For the Turdus (American Robin, but I really just wanted to type Turdus), we change from an abundance of ~1 to ~1.8. And in the Red-winged Blackbird, we see a change from ~.9 to ~5.8! Yes, that is right. The American Robin barely doubled in abundance in that time frame, while the Red-winged Blackbird came storming back to increase in abundance well over 5X!!

I rest my case. Hello Red-winged Blackbird and hello spring.

Please do not yell at me, Mama.

Want to see all that realtime? Check out this animation from eBird:

What is the indicator of spring where you live? Leave a comment below!

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Red-winged Blackbird Graph: Image provided by eBird ( and created March 6, 2019.
American Robin Graph: Image provided by eBird ( and created March 6, 2019.
Fink, D., T. Auer, A. Johnston, M. Strimas-Mackey, M. Iliff, and S. Kelling. eBird Status and Trends. Version: November 2018. Cornell Lab of Ornithology, Ithaca, New York.