Um, perhaps in order to highlight the devastation invasive species inflict on insular ecosystems?  Because you offered an example of turkeys released in New Caledonia (an island) about which I had no specific information, and have offered no more than anecdotal accounts of same?  You know, like quantifiable assessment of their impact on native flora and fauna?

Try not to let the 'impressive amount of words' overwhelm you.  I won't do your research for you, but you might go to the Cal F&G website to see their concerns about feral turkeys; one of the oft-repeated concerns in several studies is that this was a 'generalist' species which was introduced without consideration of its potential adverse impact on native flora and fauna.