Walter
Thanks
George post breeding Jett

----- Original Message ----- 
From: "Walter Ellison" <>
To: <>
Sent: Tuesday, April 29, 2008 7:49 AM
Subject: [MDOSPREY] [Fwd: Re: [MDOSPREY] Terminology question]


> Hi All,
>
> Janet suggested I send this reply I made to her off list might be helpful 
> for others on the list so I am forwarding it:
>
> Hi Janet,
>
> I am not prepared for more than the cliff notes version of this. A 
> family-by-family run down would take a lot of time.
>
> First the terms themselves:
> 1. Juvenile. Generally this applies to birds post-fledging to early 
> independence. The trouble is some birds hold a full coat of juvenal (note 
> spelling) plumage well into their first winter (e.g. gulls and shorebirds 
> [in the same order: Charadriiformes]). Long-held juvenal plumage is rare 
> in passerines (although traces sometimes stick around on stray 
> individuals) so its most typical of non-passerines such as waterbirds and 
> raptors. These days, as birders become more molt-conscious, there is 
> tendency to refer to birds with these long-term juvenal plumages as 
> "juveniles" as distinct from "first-cycle" or "first-alternate", or 
> "first-summer" whatever.
>
> 2. Immature. While this is not wrong, it's imprecise, since it only means 
> a bird that is not sexually mature. The old Peterson guides leaned on this 
> term to cover all of those nasty pre-adult plumages and age classes, and 
> the usage stuck with many birders over the years. For birds with really 
> long immaturity it's a handy catch-all, especially if you're unsure of 
> plumage sequence and molt stage -- what do you call a five-year-old 
> Wandering Albatross anyway besides fifth year or fourth cycle? You get the 
> idea.
>
> 3. Subadult is a good term for a bird that's just short of full sexual 
> maturity, e.g. a four-year old Bald Eagle or your Red-shoulder. It's kind 
> of poor for a two-or-three -year-old gull.
>
> Banders have their own terminology. They refer to birds as "HY" 
> (hatch-year), "AHY" after hatch year or "SY" (second-year) if you can tell 
> the age by plumage or other criteria, then "ASY" (after second-year) 
> unless you can go further, then it goes on to "TY", "ATY", etc. I like to 
> try to keep things clear in my posts by using reasonably current molt 
> terminology (e.g. "first cycle" or "first basic" depending on how old 
> fashioned I am feeling) or something easy to understand such as 
> "one-year-old" or some such. I hope the above discussion seems helpful.
>
> Take care,
>
> Walter Ellison
>
> 23460 Clarissa Rd
> Chestertown, MD 21620
>
> 410-778-9568
>
> Observing Nature is like unwrapping a big pile of presents every time you 
> take a walk.
>
>
> Janet Millenson wrote:
>> Based on its plumage, the Red-shouldered Hawk that's been hunting in our 
>> yard lately isn't an adult; presumably it fledged in 2007. So how should 
>> I describe this bird -- "juvenile"? "immature"? maybe even "subadult"? 
>> Different references seem to use different terms for the same thing.
>>
>> Can anyone explain the precise meaning of these terms, and how they apply 
>> to various families of birds? Thanks.
>>
>> Janet Millenson
>> Potomac, MD (Montgomery County)
>> 
>> ----------------------------------------------------------------
>> "Look at the birds!" -- Pascal the parrot
>>
>>
>>
>>
>
>