It stands to reason these same gut organisms can do the same in a bird which has eaten insects which can eat styrofoam.
Well, actually, not really. It's well known that gut flora varies from species to species and seems to be connected to phylogeny and diet. Chickens and mealworms differ pretty drastically in those senses, so there isn't any reason we should believe they have the same gut biome, nor any reason we should think they can definitely digest all of the same things.
Also, from the link in your first post:
Even if they would eat it styrofoam is obviously bad for chickens and would merely fill them up with indigestible bulk.
This was not said ironically. They go on to discuss that you can feed mealworms styrofoam, because mealworms
can digest it according to studies, and then feed those mealworms to your chickens, in a roundabout way feeding the styrofoam to your chickens. That article isn't about feeding the polystyrene directly to chickens.
There is abundant evidence that polystyrene foam IS digestible.
https://www.ncbi.nlm.nih.gov/pubmed/30145418
Again, no, there is evidence that polystyrene is digestible to insect larvae. I'm not finding any sources that definitely say birds can digest it, though I found a citation from a 1978 article about its digestibility in chickens. Unfortunately,
I'm not having any luck pulling up even its abstract to tell you what they found.
I did find another source that said it
interrupts iron absorption and transport when ingested by hens, though.
Another that said
ingestion of polystyrene by hens can lead to hexabromocyclododecane contamination in their eggs. That's a fire-retardant found in polystyrene used for insulation.
Now, I'd doubt that hexabromocyclododecane is found in cooler lids, but still... Seems to me like it's not a good idea to let the birds eat this stuff directly.
Going to have to say it’s probably more the increase in light etc with spring, but...
Gotta agree with
@Kris5902 on this one; it's the light increase that's spurring on your egg layers. I've gone from maybe one egg a day up to five or six in the past couple weeks and it's definitely still winter here, too. And my birds are not eating polystyrene.
