No, once deleted they are gone. Administrators can see some member/certification information from the 'Detailed Member Change History' report on the Reports tab, but that does not include hours.
Rather than deleting a member, we would suggest changing a member's status to one of the non-active choices, like Resigned, Retired, etc. in order to preserve records, such as Timekeeping. The status field is in the Certifications and Expirations area of the Member record.