I PERFECTY know what you mean and New Zeland its the perfect poster child why non native introductions can have a catastrophic efect on a ecossistem, however like before we are the biggest to blame. Back to the situation this species of bumble bee has so far had a minimal, if any negative inpact on New Zelands ecossistems, however they are even then try to rid themselfes of it because it polinates non native flora (ok so now it can have harmfull efects long term, yes I knowPomatomus;3908928; said:You cannot possibly believe that these are positive impacts. Your first point is speculation that native plants are surviving because of invasive pollinators. You just said that the Europeans brought invasive birds which helped the plants, yet you already stated that 25% of one native taxon disappeared after the Europeans came. You see no connection there? No competition?
This story Ive been following and I can give some income, because insolar birds allways fascinated me. And sorry my friend but you are wrong and you would know better if you knew more about this particular case. And COFF COFF this is not my speculationThis I read in a cientific paper (and yes I read cientific papers and Im a gradueted biologist
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First I dont see this particular set of birds as "invasives", they are cernatly not native but they are not invasives, cane toads, house cats and pacific rats are because they bred at a astonishing rate, are highly predatious and they are so well evolved to survive in a higly competive envoirement that native insular species simply dont stand a chance (cane toad not to blame for this birds loss). This non native birds cernatly could offer non good competition over food and nesting grounds but considering the other "neighboors" they are the least of your probs. And they wouldnt grow at a uncontroled rate because they fall prey to the same predators that preyed the native birds (the others are true invasives because they have very few natural sources of mortality)
Now to tacle the native honey creepers exctinction, most species that went extinct did so many years before this new set of birds went loose because of invasive predators, avian malaria and habitat destruction. You may argue "this new set of birds is preventing the native ones to expand their very limited range because of competition" but most native hawaian birds have VERY specialized beaks that are made to tacke very specific foods like the flowers of one particular tree species and that is one of the main keys in their decline. Many native trees became extinct or really rare after the europeans came because of habitat destruction (I know one particular is limited to clones of the same male tree and coincidently that tree polinator is extinct). The introduced species have the basic set of beaks made for seed and insect eating, so they wouldnt displace the extreme specialists (of wich unfornatly only fery few are left) and most natives now exist only in very remote places, leaving the lowlands mostly for the non natives. The main key after habitat destruction apears to be avian malaria wich claimed another species in 2007. Now the non native ones could have spread it, that is true however this desiase was not brough by them and that particular bird that disapeared was on sharp decline by many years, was never abundant and NOTHING was done to set a captive breeding program, set a reserve, etc, untill it was to late, we have nothing to blame for its disapearance and all the other species of honey creepers but our selfs. If we didnt colonised the Hawaian islands in the first place nothing would have happen to its species. We are the biggest invasive! Now back to reality we have a forest full of other species that needs its polinators and seed dispersers wich are no longer there. Coincidently the same act of introducing non native song birds to Hawai is now keeping its forests alive. If we took them out it would do way more harm then good!
The situation concerning the bees is an odd coincidence. New Zealand has more invasive species than anywhere else. It's impossible to justify the spread of such organisms because we made them extinct in their normal range when it can cause natives to become extinct.
thats why I putted it on second place) but this presents a unique and increable oportunity to put it back where it belongs. Interestingly they only sucssed in aclimatating the bumble bees into the northern hemisfere regime of seazons with the help of a bumble bee entusiast and hobbist (didnt know thouse even existed
) Is this a general way of dealing with endangered species, certenaly no but for example wild dromedarys have been extinct in their original range for hundreds of years, if again the conditions were rigth for them to live I think Australia could sher a few of its already well aclimated wild ones that after quarentine could be put back. What about arabian oryx in the Gran Canyon? Are you going to say that one of the most endangered hoved animals on the planet is a invasive too? People that had them made a mistake but now lets see the brigth side of it!Now my opinion, should non native species be introduced to a local ecossistem? HELL NO. But Im also all for exploiting what potencial good can a previously introduced non native species do for a ecossistem and the people that live alongside it, and study it insted of going all krazy, alerting the people, the filling the media, etc. Some things are pure plain pests, some like Caulerpa taxipholia are plages (this sea weed species is rigthfully banned), some are not. Many of the herps in Florida now didnt had any ecological equivalents before and are basicly filling empty niches. And then is people comparing what happened in Guam island to whats going on with burmese pythons in the Glades, totaly diferent situations, totaly diferent ways of acting!
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