dropdb weirdness

So running the following command:

dropdb -p 5443 swr

I get:

dropdb: could not connect to database postgres: FATAL:  database
"postgres" does not exist

Why is it not 'seeing' the database name I'm passing to it?  Why is it
trying to drop a database named postgres??

--
Until later, Geoffrey

"I predict future happiness for America if they can prevent
the government from wasting the labors of the people under
the pretense of taking care of them."
- Thomas Jefferson