Hi there!

We have a few sources that confirm there were indeed lobsters on the Titanic. First class passenger Mahala Douglas gave her recollections of the A la carte restaurant - "The food was superb: caviar, lobster, quail from Egypt, plover's eggs, and hothouse grapes and fresh peaches.”

There's also a surviving menu from Olympic from the following year that lists lobster as a main dish. Too add, lobster Thermidor was an incredibly popular Edwardian dish, so it's almost certain it was served on Titanic- at the very least in the a la carte restaurant.

The surviving menus from Titanic do not list lobster on that days meals, but the varying amounts of other seafoods, along with Mrs. Douglas' recollection, along with the Olympic menu give us pretty good evidence that lobster was indeed served on Titanic.

As for what happened to them- a quick google shows that it's possible for lobsters to survive up to a depth of 1570 feet, but are mostly found at a max depth of around 170 feet. Titanic lies at a depth of over 12,000 feet. The lobsters would have been crushed to death like every other living thing.