Although it looks like normal mirelurk meat, hatchling mirelurk meat is very ineffective in restoring health. Mirelurk meat and softshell mirelurk meat give +20 and +30 Hit Points respectively, while hatchling mirelurk meat only replenishes +5 and also adds +2 rads, making it as useful as any other common food item.
A large group of egg clutches can be found near the Potomac River. Going north from the Super-Duper Mart, and then west once you've reached the river, the clutches can be found guarded by a few mirelurks.