As well as an online collection of Seamen's Protection Certificates, Mystic Seaport Museum's website has research guides here:

 Seamen's Protection Certificate Register Database (via Wayback Machine)

The National Maritime Digital Library might be useful to get more background information.

Also check Cyndi's List for the category: Occupations: Fishermen & Mariners.

As well as an online collection of Seamen's Protection Certificates, Mystic Seaport Museum's website has research guides here:  Seamen's Protection Certificate Register Database (via Wayback Machine) and a database search: Registers of Seamen’s Protection Certificates.

The National Maritime Digital Library might be useful to get more background information.

Also check Cyndi's List for the category: Occupations: Fishermen & Mariners.

Cyndi's List has a topic Occupations: Fishermen & Mariners:

http://www.cyndislist.com/occupations/fishermen-and-mariners/

As well as an online collection of Seamen's Protection Certificates, Mystic Seaport Museum's website has research guides here:

http://library.mysticseaport.org/about/info.cfm?pageid=5

The National Maritime Digital Library: http://nmdl.org/index.htm might be useful to get more background information.

As well as an online collection of Seamen's Protection Certificates, Mystic Seaport Museum's website has research guides here:

Seamen's Protection Certificate Register Database (via Wayback Machine)

The National Maritime Digital Library might be useful to get more background information.

Also check Cyndi's List for the category: Occupations: Fishermen & Mariners.