The RNLI is reviewing its security procedures to ensure the safety of its members after protests in Dover and Portsmouth which saw its members targeted.
As part of this, volunteers have been told to consider not wearing RNLI branded clothing in some circumstances while representing the charity.
It comes after the charity helped carry around 120 migrants intercepted off the Isle of Wight, to Eastney, in Langstone Harbour, where roads were blocked by protesters.
Following this, some crew members had their photos and names shared on social media, in posts accusing them of treason. RNLI chief executive Peter Sparkes called the abuse "wholly unacceptable in a civilised society".
As a charity, the RNLI relies on donations from the public to fund its work.
Many lifeboat stations have shops attached to them, not just to raise money, but also to raise the profile of the organisation.
Volunteers have been told they are "empowered to make decisions to keep yourself, your team or crew safe" and "go home or close for the day if you need to".
For it to tell its volunteers they should feel empowered to shut shops or even lifeboat stations if they do not feel safe shows how seriously it is taking potential issues.
Sussex Police are looking to establish whether any criminal offences have been committed.
In a message sent to volunteers, Sparkes said its participation in the rescue on Sunday had been requested by HM Coastguard.
"This was the first time we have been involved in a Channel crossing incident of this magnitude this far west," he said.
Initially crews from Bembridge and Yarmouth stations were involved, later being joined by crews from four more stations after "large numbers of protesters were in and near the water in Portsmouth".
During the incident, the RNLI said it also helped to ensure the safety of anti-migrant protesters in the sea off Portsmouth.
BBC Verify spoke to Neil, one of the volunteers who was called a "traitor" and whose image was shared online.
"We were there, purely for the safety of the protesters in the water," he said.
"It would be nice for those people who called me a traitor to know that I'm not a traitor."
Speaking to BBC Newsnight, RNLI vice-president Sir Robin Knox-Johnston encouraged people abusing lifeboat crews to "have some sense about this".
Sir Robin, a legendary sailor who was the first man to sail solo non-stop around the world, said: "The people who are abusing the volunteers - I wonder how abusive they'd be if they suddenly got a stitch when they're out swimming?
"They'd be screaming for the RNLI to rescue them and the RNLI would do it."
In his message to volunteers, Peter Sparkes said "at times of increased media activity like this it is only natural that members of the public, supporters, family and friends may have questions about our lifesaving work in the Channel".
"When our crews are tasked by HM Coastguard, we will go to the aid of those who need our assistance, including those crossing one of the world's busiest shipping lanes in small, overcrowded and unseaworthy boats," he said.
"When called upon, we rescue people - men, women, and children - in distress."
He said the RNLI would then pass over responsibility for the people it rescued to the ambulance service, HM Coastguard, police or Border Force.
Figures from the RNLI show only a tiny fraction of its lifeboat launches involved assisting people "in distress in the Channel", with the majority of small boats intercepted by Border Force.
Sparkes encouraged crew members to take measures to ensure they feel safe in their roles.
He said volunteers could do things like "choosing not to wear RNLI branded clothing when representing our charity in public places" or removing yourself from "removing yourself from a conversation with a member of public if you feel uncomfortable".
He also encouraged RNLI members to visibly wear ID identifying themselves while on site, and to challenge anyone not wearing an ID - especially if they are acting suspiciously or trying to gain access to the building.
In a statement to the BBC, a Home Office spokesperson said: "Directing abuse at people who risk their lives in the service of others is appalling."
It said that platforms should enforce their own terms of service over this matter, and "take swift action against discriminatory content".
"Where content is shared to intimidate, harass or incite violence against someone, that can cross into criminality," they said, adding the Home Office would work "with platforms and law enforcement to ensure appropriate action is taken".
