I'm setting out on a research project to gather information to support my thesis that the reason why the First Fleet was sent to Australia was due to overcrowding caused by a growing criminal prisoner population being housed in hulks around Britain is a myth. In fact, it is a cover stroy to hide the real reason, which was based on the political and economic situation in Europe following the Seven Years War (1756 - 1763) and the granting of independence to the 13 Colonies in America. (That actually happened on 13 September 1783 when the Treaty of Paris was signed.)
The Seven Years War was a massive global conflict fought across five continents that pitted Great Britain and Prussia against France, Austria, Russia, Sweden, and Spain. Driven by imperial rivalries and European territorial disputes it lead to those countries seeking to establish colonies in the Asia-Pacific Region.
My thesis is that Britain, which wanted to secure a base in the Southwest Pacific to keep the French and Russians out, decided to establish a colony on the east coast of Australia, east of the 135th meridian, which had been claimed by Cook for Britain in 1770. An economic factor was that Empress Catherine II of Russia's policies threatened to restrict the sale of hemp. At the time, practically all the hemp and flax required by the Royal Navy for cordage and sailcloth was imported from Russia. Norfolk Island was discovered by Cook in 1774 during his second voyage. He reported that New Zealand flax (seen as a potential source of materials for rigging ships in the age of sail) grew there, as well as the stautesque Norfolk Pine, from which excellent masts and yard arms could be made for the repair of the ships of the British Navy. That is why, barely six weeks after the First Fleet arrived in Sydney Cove, Governor Arthur Phillip ordered Lieutenant Philip Gidley King to lead a party of 15 convicts and seven free men to take control of Norfolk Island, and to prepare for its commercial development. Norfold Island is probablythe only place where the term terra nullus in fact applied. Archaeological investigation suggests that in the 13th or 14th century the island was settled by East Polynesian seafarers, but human occupation appears to have ceased at least a few hundred years before Europeans arrived.
I think that the establishment of a colony on the east coast of Australia was for a clearly politoco-economic reason, and not in order to ease the discomfort of criminals. The idea that free people would travel halfway around the World into the unknown to start a colony from scratch with no guarantee of success would not provide the workforce needed by the government. So, the government gathered up a group of people who were compellable to do as directed.
Those people were found in the hulks. Horror stories have been spread about life in the hulks, but they, too, may be a mixture of reality and myth. Conditions were probably no better nor worse than in prisons on the land. Due to growing poverty of free people drawn to the cities, for men who grew destitute and faced the workhouse, life as a convict was measured out against the negatives of offending. After all, prisoners were provided with three meals a day. They left the confines of the hulks regularly to work on govrnment projects. They mastered trades and learnt to read and write. These convicts, already sentenced to transportation, provided a more competent type than could have been drawn from land prisons. Nevertheless, government officials made every attempt to make life on board as punitive as possible. Daily routines were more naval than penal.
For some information about life in the hulks, here;s a link: https://staffblogs.le.ac.uk/carchipelago/2017/10/10/a-day-in-the-life-convicts-on-board-prison-hulks/