As a birder, there is a unique and somewhat pure excitement to seeing a bird you’ve never seen before – at least that’s my experience. Spotting a “lifer” (a.k.a. a species ‘new to you’ in birding lingo) comes with a feeling of accomplishment, especially if the bird turns out to be rare. For example, I could still tell you when and where I saw my first California condor, Great bustard, or Rock wren/tuke. Some birders, or “twitchers” to separate them from more casual birdwatchers, even make somewhat of a sport out of seeing as many rare species as possible. I recommend watching “The Big Year” if you want to learn more about this and have a good laugh while you’re at it.

As a conservation biologist, spotting a rare bird often brings about feelings other than excitement. After the initial high, it leaves a little bit of a bitter taste behind because, more often than not, there is a not-so-great reason why a bird is rare.

While New Zealand’s charismatic rarities certainly are a great addition to any twitcher’s life list, I find it hard to forget that some of these species are on the brink of extinction. The birdwatcher and conservation biologist in me are at odds when I go birdwatching here, and I never know how to feel when spotting a rare bird. When I saw my first yellowheads/mohua near the Blue Pools by Haast Pass, I felt ecstatic and sombre at the same time – it’s quite the dilemma.

The upside is that New Zealanders know the value of their native wildlife and are committed to conserving it. Native birds, along with other indigenous species, are considered taonga and, as such, an important part of the country’s national identity – why else would a kiwi shooting laser beams have been such a popular design for New Zealand’s alternative flag back in 2015?

Naturally, making rare species not as rare is one of the cornerstones of New Zealand’s Biodiversity Strategy, and protecting native birds is a national priority. This goal goes hand in hand with eliminating the mammals that threaten their existence.

On a landscape scale, predator control often requires dropping 1080 (a biodegradable poison) from helicopters and planes in the rugged backcountry to target mammals in areas that are otherwise hard to reach. Experts say that for birds with a remote and inaccessible range, such as rock wrens, kiwi, blue ducks/whio, yellow-crowned parakeets or mohua, that this is currently the only practical management tool. Despite research showing that the aerial application of 1080 helps the recovery of native bird populations, this strategy is often criticised by members of the public for being indiscriminate and endangering the very species it is supposed to protect.

So, how does DOC make sure native birds aren’t dropping dead left, right and centre when they use 1080 for predator control? The answer is research, research and … more research! Preliminary research, follow-up research, and intensive monitoring of bird populations during pest control operations, all help the people in charge understand how 1080 affects native birds with the aim of reducing their poisoning risk is as low as possible during any 1080 drop.

Some of this important research was done here at Lincoln University when Jakob Katzenberger and James Ross investigated how mohua were affected by a pest control operation using aerial 1080 in the Catlins State Forest Park back in 1999. Intensive monitoring before and after the 1080 drop showed that the control operation didn’t have unwanted non-target effects for mohua. More specifically, the researchers concluded that mohua numbers didn’t differ significantly before and immediately after the control operation.

While this might not seem like the most exciting result, it tells an important story – that 1080 worked and only killed what it needed to kill. Now, in case you’re wondering if these results still hold true since the research for this study was carried out over 20 years ago – rest assured, they do. Studies conducted in the Landsborough, Dart and Routeburn valleys since then have shown that both mohua numbers and nesting success increased following predator control using 1080. In 2006 and 2009, nesting success of mohua was on average twice as high after 1080 than without it in the Dart and Routeburn valleys, and in the summer of 2015 89% of mohua nests in the area were successful.

Another key takeaway from the study by Katzenberger and Ross is that the timing of 1080 control operations is critical to maximise the benefits for native species. While the 1080 drop in 1999 did not affect mohua in the Catlins negatively, it could have provided more benefits had it been timed better. Monitoring showed that a predator boom caused by beech masting in the summer after the 1080 drop caused drastic declines in the resident mohua population. Applying 1080 after this masting event could have reduced predator numbers and, therefore, protected mohua more effectively by providing a “predator free” window for them to breed.

In 2014, DOC managed to protect mohua and other natives in a year of heavy beech masting with the “Battle for Our Birds” campaign by applying aerial 1080 just before predator numbers skyrocketed. Without predator control, that beech mast and the resulting high predator numbers would have been detrimental for the populations of native animals. This is an excellent example of how protecting native species is a learning process, and how research helps us learn, and improve conservation practices.

What we can take from this is that 1080 works and that native birds do better where it is used. Researchers don’t just leave it at that though. A lot is still being done to make aerial 1080 baiting as “bird proof” as possible and ensure that birds gain the maximum benefit from it. Baits are improved continuously, sowing rates are reduced, and bird populations are carefully monitored. Overall, 1080 baiting has come a long way since it was first done, and now is an effective tool to protect native species. Some people may always oppose the use of 1080 no matter how loud the science talks, but, to use the words of Dr Nick Smith, New Zealand’s 6th Minister of Conservation, “reason must trump prejudice about poisons when the very species that define our country are at stake”.

I consider myself lucky to have seen many of New Zealand’s birds, rare or not. Some of the encounters I’ve had here have been quite magical and, to be honest, almost cheesy. Like the time I was hiking Gertrude saddle in Fiordland, wondering if I would get to see a rock wren – only to have one poke its head around a rock to check me out while I was having lunch. Or when a family of mohua landed in the trees right next to me in Hawdon valley and I got to watch them for a good half an hour.

With research continuously improving how introduced predators are controlled, I hope that, in the future, encounters like this will once again become the rule rather than the exception.

This article was prepared by Master of International Nature Conservation student Antonia Ulle as part of the ECOL608 Research Methods in Ecology course.

Katzenberger, J.K. & Ross, J.G. (2017). Mohoua ochrocephala abundance in the Catlins following aerial 1080 control. New Zealand Natural Science, 42, 1-8.