SAN FRANCISCO (KGO) -- Another section of the old Bay Bridge eastern span came down on Tuesday. A massive engineering job took place to remove the third of five trusses.
WATCH VIDEO: Timelapse of old Bay Bridge truss removed
The truss weighs more than 25 tons and 504 feet long. It was lowered to a barge and then taken to a port to be disassembled.
The bike path on the new span was closed during the removal.
Caltrans workers made a precious discovery during the demolition.
WATCH VIDEO: Largest remaining pier in eastern span of old Bay Bridge demolished
"They discovered four Cormorant eggs. That's significant from the standpoint that we work very closely with International Bird Rescue. We have regular monitoring going on for the Cormorants and any nesting," said Leah Robinson-Leach, Bay Bridge spokesperson.
The International Bird Rescue group is now incubating the eggs; they join 9 others that were found a few weeks ago. Caltrans is trying to discourage Cormorants from nesting in the old bridge, even using sailcloth to try and block them. But some tenacious ones got through.
"We are very careful in our operation in terms of discovering any type of wildlife that is in fact protected," said Robinson-Leach.
RELATED: Demolition of old Bay Bridge span reaches milestone
The truss is the third of five that needs to come down. Caltrans set aside two days for the work, but they're getting better at it each time.
"It's very much going according to plan right now, we expect that the weather will cooperate. And if it does there is a certain possibility, I would say even probability, that the operation will not take a full day or two days," said Robinson-Leach.
Caltrans does not expect the bridge to be fully demolished until 2018.
CALTRANS VIDEO: Old Bay Bridge Pier E3 timelapse and implosion