first the hermit crabs mothers lay eggs then the eggs hatch and as soon as the eggs touch salt water, they burst open intobaby hermit crabs. Then they arelarvae. Then they grow in to adults and find a shell to live in.
Yes - and yes. Once the crabs mate, they don't live very long afterwards. The eggs are released into the sea to join the billions of tons of microscopic life floating around. With luck, some of the eggs will survive to maturity to start the cycle all over again.