What statutory duties in UK law, other than those in the question above, does the master or senior surviving officer of a UK ship have following a collision with another vessel?

Under The Merchant Shipping (Accident Reporting and Investigation) Regulations 2012, to send a report to the MAIB, and to preserve relevant evidence (see Section E). 

Under The Merchant Shipping (Reporting Requirements for Ships Carrying Dangerous or Polluting Goods) Regulations, to send a pollution report to the coastal State (see below). Under The Merchant Shipping (Official Log Books) Regulations, to make an entry in the narrative section of the OLB (see Section D).