# Banding birds query **URL:** \ **Category:** Factual Questions\ **Created:** [June 29, 2019, 7:11am UTC](https://boards.straightdope.com/t/banding-birds-query/836252 "2019-06-29T07:11:16Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [June 29, 2019, 7:11am UTC](https://boards.straightdope.com/t/banding-birds-query/836252/1 "2019-06-29T07:11:16Z")
I ran across this interesting article about finding a Golden Eagles nest: [Rare golden eagle nest found in Santa Monica Mountains for first time in 30 years](https://www.google.com/amp/s/www.latimes.com/local/lanow/la-me-ln-golden-eagle-nest-california-santa-monica-20190626-story.html%3foutputType=amp) In the article it states they banded the young eaglets. The band appear to be metal and they appear to be tight and permanent. My question is how does the band not constrict the leg of the eagle as it grows? I’ve seen adult eagles, their legs are pretty thick. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [June 29, 2019, 8:09am UTC](https://boards.straightdope.com/t/banding-birds-query/836252/2 "2019-06-29T08:09:32Z")
I am far from a bird banding expert, but the bands I have seen start out as a thin, flat metallic strip that is wrapped around the leg. The ends may overlap, but they are not glued or connected. As the bird grows, the wrap merely expands. I suppose if a leg _really_ grew, the strip might fall off, so I imagine the length is chosen for the best outcome. ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [June 29, 2019, 12:46pm UTC](https://boards.straightdope.com/t/banding-birds-query/836252/3 "2019-06-29T12:46:24Z")
Not a wild bird, but on some of the veterinarian TV shows I’ve seen episodes where a parrot owner brings their bird in because the band put on by the breeder is too tight and restrictive. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [June 29, 2019, 3:20pm UTC](https://boards.straightdope.com/t/banding-birds-query/836252/4 "2019-06-29T15:20:16Z")
> [@Musicat](#): > > I am far from a bird banding expert, but the bands I have seen start out as a thin, flat metallic strip that is wrapped around the leg. The ends may overlap, but they are not glued or connected. As the bird grows, the wrap merely expands. I suppose if a leg _really_ grew, the strip might fall off, so I imagine the length is chosen for the best outcome. In one of the articles, it showed the band which appeared to me to be metal that was bradded on. . ---
**Author:** ![Xema](https://avatars.discourse-cdn.com/v4/letter/x/9de053/32.png) [@Xema](https://boards.straightdope.com/u/Xema)\ **Post date:** [June 29, 2019, 3:31pm UTC](https://boards.straightdope.com/t/banding-birds-query/836252/5 "2019-06-29T15:31:11Z")
It’s worth noting that Golden eagles reach adult size rapidly (Googling suggests around 9 weeks). I suspect there’s not much growth left to go when banding is done. ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [June 29, 2019, 3:54pm UTC](https://boards.straightdope.com/t/banding-birds-query/836252/6 "2019-06-29T15:54:52Z")
Again, not a bird banding/ringing expert, but there are different band types for different purposed- the ones mentioned by **GaryM** used on pet birds are usually solid rings; they’re intended to be part of the bird’s ID for its whole life, and evidence that the bird is captive bred. The bird may not be legal to sell if they don’t have one. These are solid so they can’t be removed, but this isn’t usually too big a problem; they’re put on young captive bred birds at the optimum time, and there’s someone there to keep an eye on them, in case of problems like getting a loose ring caught on stuff while the bird’s still growing, or the ring getting tight due to a leg problem or unexpected growth. For wild birds, a non-joined ring is [used](https://youtu.be/5MkR51RLu1E?t=44), as part of projects recording population dynamics and migration and the like. This is partly because it’s obviously more risky for a wild bird to have a non-removable ring, if it gets caught on something or gets a swollen leg there’s no-one going to rescue it or take it to the vet to get it removed. There’s also less need for permanence; while those studying birds would obviously rather the ring stayed on for the whole course of the project, it’s not worth risking a bird’s life for. These can be fitted onto adult birds, which is good for studies, but useless as evidence of captive breeding or permanent ID. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [June 29, 2019, 4:21pm UTC](https://boards.straightdope.com/t/banding-birds-query/836252/7 "2019-06-29T16:21:29Z")
> [@Filbert](#): > > For wild birds, a non-joined ring is [used](https://youtu.be/5MkR51RLu1E?t=44)… Did you actually look at the photos in the accompanying article? ---
**Author:** ![busterpickle](https://avatars.discourse-cdn.com/v4/letter/b/258eb7/32.png) [@busterpickle](https://boards.straightdope.com/u/busterpickle)\ **Post date:** [July 1, 2019, 1:25am UTC](https://boards.straightdope.com/t/banding-birds-query/836252/8 "2019-07-01T01:25:21Z")
Indeed, a riveted band as depicted on this USGS site, see number three: https[:][//www.usgs.gov/centers/pwrc/science/about-federal-bird-bands?qt-science\_center\_objects=0#qt-science\_center\_objects](https://www.usgs.gov/centers/pwrc/science/about-federal-bird-bands?qt-science_center_objects=0#qt-science_center_objects) Also of note, rivers bands are used on eagles, and as these are eagle chics that makes sense. I also imagine these people know what they are doing and have performed this many times. Possibly the depth of field in the pictures prevents an accurate depiction of how much room is left around the band. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [July 1, 2019, 3:15am UTC](https://boards.straightdope.com/t/banding-birds-query/836252/9 "2019-07-01T03:15:57Z")
> [@Lucas\_Jackson](#): > > I ran across this interesting article about finding a Golden Eagles nest: [Rare golden eagle nest found in Santa Monica Mountains for first time in 30 years](https://www.google.com/amp/s/www.latimes.com/local/lanow/la-me-ln-golden-eagle-nest-california-santa-monica-20190626-story.html%3foutputType=amp) > > In the article it states they banded the young eaglets. The band appear to be metal and they appear to be tight and permanent. My question is how does the band not constrict the leg of the eagle as it grows? I’ve seen adult eagles, their legs are pretty thick. Birds are typically close to adult size by the time they leave the nest. While I haven’t banded raptors myself, I expect they would have waited to band the chicks until just before fledging, and made any allowance for expected growth in determining the size of the band to use. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [July 1, 2019, 1:53pm UTC](https://boards.straightdope.com/t/banding-birds-query/836252/10 "2019-07-01T13:53:02Z")
Thank you.