Using my 35x zoom that so often comes in handy for close signal photos I noticed a mess of sticks on top of the US&S position light head as well as a lot of white splotches in and around the maintainers gantry. If that wasn't enough of a giveaway an Osprey was perched on this rather impressive nest scanning around for food or other threats.
Also known as the Sea Hawk, ospreys live near water and build large stick nests in elevated positions where they can survey said water for prey.
While these particular signals are not in any risk of being replaced, had they been a nest of this type may have thrown a significant wrench into the project timeline as I am fairly certain it is against Federal law to interfere with the occupied nest of a Bird of Prey, although I'm sure there are probably ways around it. It also shows how signaling structures can provide valuable habitat for raptors and other flying creature...like wasps.
I am some come winter some maintainer is going to have a fun task knocking down the abandoned nest. Fun part is when the birds, which mate for life, return to build the nest again in the same place.