Tracy I'm not sure where to post this. Nice video.
https://www.youtube.com/watch?v=08eDN1csgRA&feature=youtu.be
Nothing wrong with it's location
as it is more of a news story than just a video. I've tweaked your title to make it easier for folks to find later.
I'm interested in this phrase from the text below the video: "The outcome is not likely to be a good one for the young." Not sure why they say this ... other than perhaps imprinting on peregrines but I don't know how much gulls will imprint on another bird species. As for diet, Herring gulls are omnivores so they can digest meat just fine - not sure what the proper balance is for growing chicks but so far this peregrine seems to have managed very nicely. As for when they fledge, according to what I know about herring gulls, they often get separated separated from their parents, live on their own before hooking up with other gulls - sounds like that part is hardwired in which case, they may be a herring gull with an odd background but still a herring gull. Since peregrines don't as a species demonstrate any infanticide or siblicide behaviour, not sure that's a big issue ....
Also, the herring gull is a "red" listed species by the RSPB in the UK
http://www.rspb.org.uk/wildlife/birdguide/name/h/herringgull/index.aspx (click on the Red button to find out more about the classification)