Dear Mr. Klima,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog for “Abwehr” and “Navy.” The search produced the following results. In addition, we suggest reviewing the Records of the German Navy available on Microfilm Publication T1022 as they may contain files of interest to you.
Also, please consult two particular Record Groups: Records of the Chief of Naval Operations (Record Group 38) and Records of the Naval Districts and Shore Establishments (Record Group 181). Within records located in Record Group 38, there are two series of records that could be of interest to you titled “Classified Administrative Correspondence” and “Central Administrative Correspondence.” These records are arranged by the Navy Filing Manual (4th Edition, 1941). The best filing designations to start with are:
A8-5 is for counter-intelligence/espionage
ND# is for a specific naval district - ND3 is the 3rd Naval District.
P8-2 is for a particular organization
QQ is for an individual
EF30 is for Germany
They can be used in different combinations as well.
Within records located in Record Group 181 there are records located in NARA’s regional archival offices such as New York or San Francisco. In these regions, there are records relating to the District Intelligence Officer (DIO) who would have overseen the counter-intelligence operations for the Navy at the Naval District level. If there is not a DIO specific series, then the records might be filed in the Commandant of the Naval District's correspondence. Records in these series are also arranged by the Navy Filing Manual (4th Edition, 1941). An example of what you can find in the finding aids could be A8-5/QQ/ND3/EF30 which means a counter-intelligence file on German or German sympathetic individuals in the 3rd Naval District (New York).
In most cases, but not always, file designations QQ and P8-2 will have specific names following afterward (e.g. A8-5/P8-2/Nationalist Socialist Party USA or A8-5/QQ/Friber, Bob).
In addition to these series of records, we suggest that you search the series titled “Monograph Files Relating to Germany” and the series titled “Secret and Confidential Reports of Naval Attaches”. The latter series has an index that is available online (National Archives Microfilm Publication M1332). Most of the reports are from outside of the US, but they might mention information of German intelligence being conducted in the US from an outside source.
We hope this information is helpful. Best of luck with your research!