I did not mind as I was standing watch in any event.
When the weather calmed down I decided to do a little research on anchoring rights as this situation will certainly occur. Here what I found:
Since anchors are as important to boats as brakes are to automobiles here is
what to do if someone anchors too close to you for comfort:
The first boat to anchor has certain rights over others who later anchor nearby.
These rights spring from common courtesy and practical seamanship, but they are also backed up by law.
A boat already anchored must be given room to swing freely, and she must also be allowed maneuvering room if she wishes to depart.
This can mean significant room in the case of an engineless sailboat.
If you, as first boat in the anchorage, notice another boat attempting to anchor too close to you, your first responsibility is to inform the newcomer of the possibility of fouling.
Decision No. 124-5861 (1956) in U.S. Admiralty case law states: “A vessel shall be found at fault if it . . . anchors so close to another vessel as to foul her when swinging . . . (and/or) fails to shift anchorage when dragging dangerously close to another anchored vessel.
Furthermore, the vessel that anchored first SHALL warn the one who anchored last that the berth chosen will foul the former’s berth.Note, however, that if you start to drag anchor and threaten to collide with another vessel, it doesn’t matter that you anchored first.
A dragging boat MUST take immediate action to avoid collision and find a new berth.
Source: McGraw-Hill Boating Encyclopedia: Anchoring Rights : http://www.answers.com/topic/anchoring-rights
As a prudent person I did put 4 fenders in case we would have a collision...
This is a lesson learned for me as next time I will politely inform the captain that:
Under the United States admiralty law (or maritime law), it is my first responsibility to inform the master of a Vessel that his vessel shall be found at fault if he anchors so close to my vessel as to foul her when swinging.