History shows that colonizers are only interested in creating healthy environments for themselves as they leave their own overcrowded, polluted, impoverished countries behind.  They eventually pollute and degrade the places they colonize which was/is the reality of North and South America.  West coast salmon habitat was degraded by the destruction of the old growth forests and east coast cod were devestated by commercial over-fishing.  Pristine lakes and rivers are contaminated with  industrial effluent and sewage which results in diseased inedible fish.  Nothing to brag about there.