In the second picture of the two fish, where they contact one another, you can see what appears to be a white edge to the tail fin of the fish beneath the other. I only know of one kind of fish that has a white edge on it's tail fin, and that is a Brook trout. IIRC, Brook trout are native to the New York area.
Here is a picture of a Brook trout. Perhaps you may recall other details that aren't visible in the photographs that might confirm this identification.
In the picture with many, many fish in it, that all appear to be the same kind of fish, there are several places in the photograph where similar thin white strips appear, that could also be such white edges of Brook trout fins. I don't know what kind of trout are in the Cold Harbor hatchery, but it would make sense that they were Brook trout if that is the native species of trout in that area.
I live in the Pacific NW, where there are Rainbow and Cutthroat trout, and Bull trout, or Dolly Varden. They are rare here, but I have seen many Dolly Varden in Alaska, where I grew up. I have found Brown trout here as well, in inland rivers, where they were planted by immigrants from Germany I am told, and I have heard there are Brook trout in mountain lakes. I have not been to any mountain lakes and seen Brook trout. However, AFAIK there are no other fish with such a white stripe on the edge of their fins than Brook trout, so that is my best guess as to the identification of the second fish in those pictures.
Thank you. It is definitely stocked with brook trout. The next time I write a blog about this hatchery, if I need fish identified I will surely tag you and ask for your help.
Thanks again, @valued-customer
I will be happy to assist as I can, but please keep in mind I am unfamiliar with the species of the Eastern seabord.