A fascinating and useful browse through Aotearoa's history of rodent eradication. And now we can watch a kākāpo and her chick live on Whenua Hou. Amazing.
Thank you. I'm hopeful for this year's breeding season! And it's amazing watching the kākāpō cam. Even if she isn't doing much, they are such adorable birds.
Interesting conundrum:having to use a long-lived toxin to eradicate invasive species with pros (very effective at intended task) and cons (collateral loss of other species with long-term effects on the island ecosystem unknown-I'm guessing on this one).
Still saving highly endangered species is likely going to be worth the risk.
It is. Because these islands are so important, there has been a lot of followup monitoring, with some fascinating results. There's no evidence of long-term impacts from the toxins (more than a year or so) but the plants and animals don't always respond as expected, and there are often winners and losers. Sometimes weeds get out of control without their seeds being eating (also an issue with goat and rabbit eradications). In one of the Ahuahu islands, a rare native vine went rampant and killed several ngaio trees. Some insects and reptiles increase after eradication while some stayed the same or even declined, possible due to more insect-eating birds being present.
It's something that I learned when managing invasive weeds - there are always impacts from control (even without chemical treatments), and there needs to be careful thought into whether it's worthwhile
Good article! 1080 aerial drops get all the publicity, but in terms of persistence in the environment it is "safer" than Brodificoum - a scientist involved with pest control in native forest areas told me that when the 1080 backlash was at it's height, & said they personally agreed the benefits to taonga species survival & recovery using either were worth it on balance, but 1080 was actually less cruel & environmentally less persistent (mainly for likes of cats/dogs or other species eating toxic corpses) The facts about rats being bait-averse if they get sick, is why, for 1080, there is a pre-bait drop of pellets with no poison so that the rats DON'T get sick, and gobble up the poisoned baits that are dropped next. I can see why Brodificoum would be a "one and done" option - I wonder what the cost-benefit analysis between the two is? Guessing some of it comes from WHERE each is used, as you say, areas where people LIVE & where they don't? NB People "live" in many native forests as in walk tracks, stay in huts, tent, hunt etc
I have personally seen the difference both eradication & suppression of rats, stoats, possums have had on endemic species survival & recovery, but as with most I am excited about some of the newer methods & strategies being developed & hope "non-toxic" or species specific solutions become viable solutions in the near future. I mean, even re-setting traps are a big advance in recent times, plus AI monitoring to close traps if a non-target species tries to enter just blows my mind!
A fascinating and useful browse through Aotearoa's history of rodent eradication. And now we can watch a kākāpo and her chick live on Whenua Hou. Amazing.
Thank you. I'm hopeful for this year's breeding season! And it's amazing watching the kākāpō cam. Even if she isn't doing much, they are such adorable birds.
It's amazing how all these efforts were led by far sighted individuals who had to.push against established views of what was possible..eg
IAN Atkinson on possums on kapiti and ROWLEY Taylor on breaksea Island
Absolutely. We owe a lot to those who believed these things were worth trying. And put all the hard yards into making it happen as well.
Interesting conundrum:having to use a long-lived toxin to eradicate invasive species with pros (very effective at intended task) and cons (collateral loss of other species with long-term effects on the island ecosystem unknown-I'm guessing on this one).
Still saving highly endangered species is likely going to be worth the risk.
It is. Because these islands are so important, there has been a lot of followup monitoring, with some fascinating results. There's no evidence of long-term impacts from the toxins (more than a year or so) but the plants and animals don't always respond as expected, and there are often winners and losers. Sometimes weeds get out of control without their seeds being eating (also an issue with goat and rabbit eradications). In one of the Ahuahu islands, a rare native vine went rampant and killed several ngaio trees. Some insects and reptiles increase after eradication while some stayed the same or even declined, possible due to more insect-eating birds being present.
It's something that I learned when managing invasive weeds - there are always impacts from control (even without chemical treatments), and there needs to be careful thought into whether it's worthwhile
Good article! 1080 aerial drops get all the publicity, but in terms of persistence in the environment it is "safer" than Brodificoum - a scientist involved with pest control in native forest areas told me that when the 1080 backlash was at it's height, & said they personally agreed the benefits to taonga species survival & recovery using either were worth it on balance, but 1080 was actually less cruel & environmentally less persistent (mainly for likes of cats/dogs or other species eating toxic corpses) The facts about rats being bait-averse if they get sick, is why, for 1080, there is a pre-bait drop of pellets with no poison so that the rats DON'T get sick, and gobble up the poisoned baits that are dropped next. I can see why Brodificoum would be a "one and done" option - I wonder what the cost-benefit analysis between the two is? Guessing some of it comes from WHERE each is used, as you say, areas where people LIVE & where they don't? NB People "live" in many native forests as in walk tracks, stay in huts, tent, hunt etc
I have personally seen the difference both eradication & suppression of rats, stoats, possums have had on endemic species survival & recovery, but as with most I am excited about some of the newer methods & strategies being developed & hope "non-toxic" or species specific solutions become viable solutions in the near future. I mean, even re-setting traps are a big advance in recent times, plus AI monitoring to close traps if a non-target species tries to enter just blows my mind!