Red-shouldered hawk (again)

[smittyone@cox.net]

I've been going through the archives again and dredged this one up.  This buteo was seen waaay back in August 2021 at Loess Bluffs, MO, and identified by you good folks as a young Red-shouldered Hawk.  I agree with that call.  But when I searched for corroborating images of what a  young Red-shouldered Hawk should look like, I found a handful that looked nearly identical to mine.  But only a handful.  Most of the other pics of immature birds that I found looked more like I though a Red-shouldered Hawk "should" look like--not very much different than an adult.  So, long winded preface out of the way, why does it look like this?  Is it a newly fledged bird?  Do they go through more than one plumage stage before displaying full adult features?  

 

Follow-up questing regarding Red-shouldered Hawk in general.  According to eBird, there are three subspecies.    Buteo lineatus extimus in Florida, Buteo lineatus elegens along the west coast, and Buteo lineatus Group for the entire eastern half of the CONUS.  What is lineatus "Group" mean?

[Snake Fingers]

Uh nuh. Not even gonna try.

[Jerry Friedman]

I think the difference between this juvenile and others it's just individual variation.

A subspecies group is just a group of subspecies that resemble each other and probably have nearby ranges.  The lineatus group consists of the subspecies that live in the eastern U.S. north of the Florida Peninsula and can't be distinguished in the field.

Another example is that in Dark-eyed Juncos, there are two subspecies in the Slate-colored group and four in the Oregon group.

[DLecy]

Because subspecific taxonomy has a tendency to change over time, my understanding is that when one or more subspecies is ill-defined or somewhat controversial, it is common to link that subspecies with others in a “group.” Fox Sparrows and Dark-eyed Juncos come to mind immediately. For example, there are currently 19 different subspecies of Fox Sparrow, sorted into four groups. Some of the subspecies are not clearly defined and/or representative of intergrades. 
 

As for RSHA, I think many authorities consider texanus to be a part of alleni instead of a distinct subspecies. 

[Jerry Friedman]

48 minutes ago, Jerry Friedman said:

...

Another example is that in Dark-eyed Juncos, there are two subspecies in the Slate-colored group and four in the Oregon group.

Make that six in the Oregon group, including two in Mexico.  Or seven if you count Pink-sided, but people should really be past that.

https://avibase.bsc-eoc.org/species.jsp?avibaseid=B1019ACBC49773AC

[smittyone@cox.net]

So there's a 4th and/or 5th subspecies of Red-shouldered Hawk?

I'm fine with delving into subspecies (to a degree), but I'm not touching sub-subspecies.

If I understand, west coast and Florida versions are delineated, but eastern CONUS is generic?  Or are you saying the eastern "Group" also includes the two south Texas ones?

Non-related remark.  After photographing about a dozen Red-shouldered Hawks over the last couple of years, every single one has been in NW Missouri, and every one has been an immature bird.  I have seen an adult only once (also NW MO), and a photo was impossible.  

Two species who's plumage differ drastically from young until adult are Bald Eagles (of course) and Northern Harriers.  I'm sure there's many more.  But I'm not so sure this young bird's plumage is just a "variation" since it's the only one I've encountered that looked like that.  If it was perhaps one of the subspecies that's not normally seen in the area, that would make more sense to me.  

 

 

Edited March 6 by smittyone@cox.net
added clarification

[smittyone@cox.net]

From ADW, "Five subspecies of Buteo lineatus are recognized. These subspecies are separated based on geography and physical characteristics. The head and breast markings of the Florida subspecies, Buteo lineatus extimus and Buteo lineatus alleni, are slightly paler than other Red-shouldered hawks. The California subspecies, Buteo lineatus elegans, and the Texas subspecies, Buteo lineatus texanus, however, have vibrant, deep red markings on the lesser secondary upperwing coverts, underwing coverts and breast. (Christopher, 1990; Clark and Wheeler, 2001; Crocoll, 1994; Whetmore, 1965; Woodward, et al., 1931)"

This publication mentions 5 subspecies, then only lists 4 of them.  Maybe I should just stick to Red-tailed Hawks.  Time for more aspirin.

[DLecy]

14 minutes ago, smittyone@cox.net said:

From ADW, "Five subspecies of Buteo lineatus are recognized. These subspecies are separated based on geography and physical characteristics. The head and breast markings of the Florida subspecies, Buteo lineatus extimus and Buteo lineatus alleni, are slightly paler than other Red-shouldered hawks. The California subspecies, Buteo lineatus elegans, and the Texas subspecies, Buteo lineatus texanus, however, have vibrant, deep red markings on the lesser secondary upperwing coverts, underwing coverts and breast. (Christopher, 1990; Clark and Wheeler, 2001; Crocoll, 1994; Whetmore, 1965; Woodward, et al., 1931)"

This publication mentions 5 subspecies, then only lists 4 of them.  Maybe I should just stick to Red-tailed Hawks.  Time for more aspirin.

Don’t forget nominate lineatus.

[Snake Fingers]

And this my friends, is why I don’t care for buteo ssp…