18 December 2014

Shadow chasing – When monitoring tui requires the mindset of a Ghostbuster

Vanessa Mander is a post-graduate student studying for an MSc in conservation and ecology at Lincoln University. Here she tells us about radio-tracking tui.

Ever since I was a young girl I have always wanted to be a scientist, long before Lego could influence my choice of career with their ‘female’ scientist figure. I was not drawn to being a Barbie (those that know me will be rolling on the floor laughing right now), nor a fashion editor (again, people are struggling to breathe for laughter) as my heart was always drawn to New Zealand's wondrous and unique flora and fauna. Initially, I thought I would work in a lab, I always had a knack for chemistry and so my first stint in university around 15 years ago produced a run-of-the-mill BSc in chemistry.

Life intervened and I found myself working for the government in tax issues and tax law, working as an accounts nerd and being the ultimate domestic child-wrangler/executive/CFO. Not the career I had envisioned but one I am still immensely proud of. It was a family holiday to Stewart Island that led to an epiphany of sorts. We took the kids on a trip to Ulva Island, a predator free island where many species of endemic New Zealand birds find a safe haven. While walking amidst the beauty of the forest we encountered a South Island saddleback (Philesturnus carunculatus) collecting nesting material in preparation for breeding. I was spellbound, elated and excited all at the same time and I knew that this field was the science career I wanted to embark on. After some personal research, I enrolled for the Master of Science at Lincoln University, where Dr Laura Molles presented me the opportunity to participate in a research placement tracking tui (Prosthemadera novaeseelandiae) in conjunction with the Banks Peninsula Conservation Trust (BPCT). I felt that I had been given a gift, one that would provide me with valuable skills and a taste of a dream coming true.

Most of my work in this placement involved radio telemetry. The receiver and aerial combo is reminiscent of the 1980's Ghostbusters films. Five tui had transmitters fitted, two of which had been recently attached so the likelihood of getting a signal appeared high. The three older transmitters were either found on the ground or ‘missing-in-action’, which left me tracking the female ‘Putiputi’ and the male ‘Yeah Right’. (Naming rights are given to individual sponsors of the Tui Reintroduction Programme through the BPCT. In the case of the male, by someone with an interesting sense of humour.)

A tui dude with attitude.
Used with permission from Patsy Dart.
Tracking tui is like a shadow hunting expedition. You spend many hours believing that they must be close by because the receiver tells you that they are, and then there are the moments that you strain to hear what you believe is a distant tui call, only to second guess yourself and think that maybe your mind is playing tricks and maybe these birds aren’t real. There were weeks where a signal was obtained but sightings of the bird eluded us. Taunting seems an appropriate word but I realize that this is somewhat forces a human personality to this behaviour. To be honest, sometimes it’s hard not to.

The ‘shadow chasing’ experience was the single most challenging aspect of this work as you often went unrewarded and somewhat unsatisfied, knowing that the target bird was in the area yet not sighting it. Frustrations don’t end there. Reading a bird’s unique combination of leg bands is often the only way we can confidently identify a bird. This only works if you are: close enough to pick the band colours and order (binoculars are ok), AND the birds orientation is sufficient that both legs are visible and not obscured by the tail, AND the tui are perched on appropriate materials that do not obscure the leg, AND bands are even present – unbanded birds appear to flaunt this a bit. In most circumstances where one or more of the conditions above are not met, there would be a fair bit of fist-shaking at the sky.

The study conducted over twelve weeks found that Putiputi remained mainly within the Akaroa region, her excursions away from the core Stony Bay Rd area (in Akaroa) decreased as breeding season approached. In this time she appeared to entertain the idea of pairing with ‘Charlie’, only for him to be replaced with ‘Laurie’ a few weeks later, she is picky apparently.

Yeah Right proved to be a traveller. He was banded and originally tracked around the Akaroa area too… handy for me doing the tracking to be sure. However, we lost the signal after a few weeks and I was a little sour about that. Fortuitously, I happen to be looking for some lost transmitters in the Okuti Valley, near Little River, and picked up a signal… from Yeah Right! His story was that he had migrated to the Okuti Valley and remained there right up to the breeding season.

Tui at the sugar water feeder in a private garden.
Used with permission from Patsy Dart.
Honestly, there were times that I would despair that I would see any tui. This was generally when the weather was less than optimal and the ‘shadows’ seem relatively distant. However, you were rewarded, just often enough, with glimpses into their lives… whether it was a territorial display, a soft chortle between potential pairs or just the pleasures of watching them feed, to nourish you for the dry times ahead.

The knowledge and insights I will take away from this experience include:
1. Fitness is everything (mine and birds… but mainly mine),
2. Patience is a virtue (birds have it but I am still working on that one),
3. Tui are not people no matter how much they seem like they are,
4. New Zealand is so much richer for having such a beautiful and charismatic bird.

I choose to use the term shadow-chasing because, although it accurately describes my tui experiences, it also has parallels in my life to date, except now I am glimpsing parts of the ‘career’ shadow owner and I hope to catch up with them soon. 

As the saying goes “the early bird gets the worm but the second mouse gets the cheese”! (Willie Nelson).

Darwin and the Sandwalk - Upgrades

Here's an issue that certainly causes problems today!

17 December 2014

Darwin and the Sandwalk - Cousin

Another Sandwalk. I always thought it ironic that Darwin married his cousin and then spent a lot of his later life worrying about the wisdom of this from a 'fitness' point of view. I guess he was the first to have this worry! For the other Sandwalk cartoons, click on 'cartoon' in Labels below.

16 December 2014

Darwin and the Sandwalk - Sponsors

Another Darwin cartoon from the old SYSTANZ newsletters. The cartoons were put together by Cor Vink and I. At the time Cor was an invertebrate technician and later my PhD student. Cor now is a curator at Canterbury Museum in Christchurch. Cor would do the drawing and I would usually come up with the idea. In this one we wondered what it would be like if Darwin worked in today's environment.

15 December 2014

Darwin and the Sandwalk - Origin

Back around the start of the earthquakes I was putting some old cartoons of Darwin on the Sandwalk (his private walk around the woodland at his estate which he ambled about most days to get in some serious thinking time) online. I have been doing my once a decade office tidy and came across some more Darwin on the Sandwalk from 15 years ago or so. The idea was that it would be useful to know what Darwin thought about as he paced the Sandwalk. Another complementary theme was using this to explain why Darwin took so long to write and publish 'On the origin of species'. These cartoons first appeared in SYSTANZ newsletters in the 1990s. I also found the short-lived Unrootedtreeman cartoons. Expect to see them soon. Enjoy.

11 December 2014

Let's stick together

It's been just over four years since the Greendale 7.1 earthquake that shook us up here in Lincoln and almost four years since the major aftershock that destroyed a good chunk of Christchurch. Time flies and time heals. There are few signs around Lincoln of the quakes (although the local Catholic church was only demolished this week after being empty and forlorn for all of this time). Around the university we still have several large buildings that have been closed since the quakes and are yet to be demolished. Overall, though, Lincoln and its surrounds are going well. It's a different story in Christchurch. While much of the demolition around the city centre has finished and there is a forest of cranes and building sites, as we move out further east towards the seaside we come to major areas of damage that are little changed since the fateful day in February 2011. I travelled through these suburbs on the weekend and it is genuinely distressing to do this. The people living in these areas with wrecked roads, poor infrastructure, no real drainage and so on must be truly resilient (or numb). Probably one of the most affecting sights are the large tracks of suburbs where scores of houses have now been removed and the land is becoming unkempt wilderness. Whole streets of houses are gone. Dotted in amongst these wild areas are houses and families who, through the oddities of these kinds of events, were fortunate to be living on a slightly rocky substrate, or a fractionally higher rise. As I drove around, feeling slightly seasick on the undulating roads, I wondered how these isolated homes could keep a sense of connection in these areas that once had tightknit communities.
High Street, Christchurch

A lot of the people from these areas have moved to various outlying towns like Rangiora or Rolleston. So are there now little bits of New Brighton in Amberley? Or pieces of Parkland in Halswell? That's unlikely as people from this diaspora have gone in all directions. They will have to adapt and change to the communities that they move to. There seems to be a number of links between what has happened in Christchurch and issues that we have in conservation.

As populations decline you have a few options. You could halt the decline and then grow the population again (in New Zealand this often means controlling introduced predators). You could move the local population to another safer or more productive site (in New Zealand such translocations have often been to offshore islands). In the near future you will be able to clone and artificially generate genetic variation in individuals. However, much of this work involves single species translocations. This is like moving one family out of their suburb. Will they like and flourish in the new site? Time will tell. Will they retain the attributes of their original community? Unlikely. What if we could relocate whole streets of families to new streets elsewhere? Will they like and flourish in the new site? Again, time will tell. Will they retain the attributes of their original community? The chances are much higher.

Stephane Boyer from Lincoln University has suggested that conservation translocations would be much more successful if they are community translocations. He has published in Science on this topic. Stephane has worked in mitigating the effects of open mines. One of the techniques that they have shown to work is in taking soil, plants, and the invertebrates and microbes that come along with them, and placing the whole lot in a different site. This is remarkably successful in allowing these communities to survive and to remain functioning much as they have always done. He argues that in conservation translocations, we should also be more focussed on moving multiple species from an area and not just an endangered birds or plant. As we move into a period of climate change, where whole local habitats are threatened, we may need to increasingly think about using these techniques. There might also be some ideas that we could take from this to help with preserving human communities.

Postscript: Less than a day after writing this piece we were woken in the wee hours by a magnitude 4.5 aftershock centred more or less under Lincoln. That was the 542nd aftershock quake since September 10 2010 to register over 4. As I lay in my bed wondering whether this was going to escalate in something nastier I did think back to this article and thought that one doesn't have to go over to the centre or eastside of Christchurch to be reminded of the legacy of the quake.

27 November 2014

The things we leave behind

Sometimes I wonder what people would be able to deduce about me from looking at my office. If someone came in snooping I'm sure that they would get some understanding of me, even if I was absent, simply by looking at what I leave behind. Of course there are some obvious things. I have what I like to think of as a typical academic's office, messy, possibly chaotic, a sense of personality, perhaps a sense of busy work. Of course not all academics are like this but there are plenty who are, like one of my corridor neighbours Tim Curran. Another neighbour, John Marris, has an immaculate office with everything in its place but, then, he is the curator of our entomology museum and so being precise and particular comes with the territory. Another neighbour, James Ross, also has a extremely tidy office. He is a regular academic, so no real excuse, and I find entering his office quite daunting. There is certainly some reflection of their offices into how they run the rest of their lives.
Adrian's office - typical academic?

Turning to my office in more detail, such a snoop might gaze at my desk. At first glance (and at multiple glances really) there are many chaotic piles of paper. Perhaps evidence of a person that can multi-task and perhaps they use chronological filing? There is a pile of documents on new course development administration, another with an attempt to write a children's story on insect identification, still another of recent papers (on explanatory power in ecology, self-immolation in plants, evolution of sex chromosomes, convergence of lizard morphology on islands and getting DNA from possums), and another with an odd collection of names of potential candidates for the Canterbury Country Under 15 cricket team, Adrian's postgrad students monthly funding, a design for next year's research methods course and a document about the appraisal of the local primary school principal. What would my snoop make of these? Perhaps that Adrian spends a lot of time on teaching committees, perhaps has had kids and likes to write, has a wide range of research interests, is involved in cricket coaching, supervises postgrad research, is proactive about getting ready to teach a course 3 months away, and is involved in governance at the local school. All correct. Looking closer they might observe some D and D dice (so a nerd!) and a dinosaur (so a science nerd!). Looking around my room the snoop would see from my posters that I have an interest in movies and Darwin and my books and 'toys' would confirm it.

As individuals move through the world they interact with other individuals and other elements of their environment. Every interaction leaves something behind, whether intangible, say a memory, or tangible, say a footprint. Individuals are constantly leaving clues about themselves behind. This is one of the reasons that we are uncomfortable with our new online existence, how it is possible for anyone with the right access to know almost everything about you! Of course, there is something even more personal that you leave behind you everywhere you go - your DNA. We live in a sea of DNA. Every living thing around you has DNA. All of the cells that you are constantly shedding have DNA. The DNA ranges from fully functioning in living cells to various states of decay in nonliving cells. Everything you touch, everywhere you breathe, leaves behind DNA. Most times this is in very low quantities but this can still be detectable. One of my students just found that in a few ml of seawater taken at a local shore that we could detect shark and seahorse species that are swimming about in the area! (More on that at a future time) Because of the presence of this sea of genetic material, DNA is a great potential resource for ecologists and conservationists.
A waxtag, complete with possum bites, saliva and DNA

As ecologists we often deal with animals that are difficult to find or detect. Usually, we want to monitor populations to find out if they are increasing, moving, changing in age structure and so on. For many species this is difficult. They might be nocturnal, or cryptic, or in tough terrain, or small, or dangerous, or - well you get the picture. Being able to detect where individuals have been (even if they have moved on now) is a very useful ability. We have cameras that detect motion, tracking tunnels that record footprints in ink, GPS collars that can be attached to an individual and then followed. These are all useful methods. Here at Lincoln we do a lot of work on possum behaviour. One method for inferring possum presence is to put out waxtags which possums happily bite and leave tooth marks on. We can collect these up and know that at least one possum came past and bit the tag. Sometimes we would like more precision. We want to know how many possums came past and bit the tag. Were they males or females? The bites don't tell us that kind of information. However, the possums leave more than just the bite marks, they also leave DNA that is present in their saliva.

In a new study by masters student Juan Duenas, with James Ross and Rob Cruickshank, just published in New Zealand Journal of Ecology, it is confirmed that possum DNA can be collected from saliva on waxtags. More impressively, enough microsatellites (highly variable areas of DNA) can be distinguished to identify individuals (a kind of genetic fingerprinting). The DNA doesn't come easily though as it quickly starts to degrade in the saliva and then on the waxtag itself. The tags were bitten by possums at some point during the night of collection and their DNA was only just good enough, condition-wise, in the morning to actually be decoded. Still, this is a good step forward, we can use the DNA that possums leave behind to find out how many individuals are in an area, where they might have moved into the area from and what the sex ratio might be. This is all information that is very difficult and labour intensive to collect otherwise. The DNA that organisms leave behind is becoming a very powerful tool for understanding the private lives of these individuals. I wonder if my snoop has a DNA kit....