This post is a republication of a piece that Chrissie wrote for http://www.chathams.co.nz. You can see the original here.

Most people visit the Chathams for the wild scenery, the precious bird fauna or the unbeatable fishing. But for me, the main reason for wanting to visit the Chathams was to finally meet the Rangatira spider (Dolomedes schauinslandii). Despite being the stuff of legend due to its whopping size and stout hairy legs, this species is no longer easy to see due to its disapperance from main Rēkohu/Wharekauri/Chatham island.

Once found across the Chatham archipelago, the Rangatira spider is now restricted to Hokorereoro/Rangatira, Maung’re/Mangere, and Houruakopara islands, making it an At Risk (Relict) species. I was lucky enough to spend two weeks on Maung’re/Mangere and Hokorereoro/Rangatira islands in November 2020, where I joined the Department of Conservation Flora and Invertebrate Monitoring team. In addition to general invertebrate monitoring on the islands, I made the most of the chance to be in such a special place, and got to know the spectacular Rangatira spider.

As a behavioural ecologist specialising in the evolution of animal mating systems, I was particularly interested in learning more about the sex lives of these spiders. The Rangatira spider is one of more than 100 species in the Dolomedes genus, which are found all over the globe and can have truly bizarre mating features. For one relative in the USA (D. tenebrosus), things have gotten seriously extreme: in this species the males, which are tiny compared to the much larger females, mate and then spontaneously die – their hearts literally stop beating! Hanging from the female while their genitals are still inserted, they are eventually consumed by the female – quite a dramatic way to go!

In my lab at the University of Waikato we have recently learnt more about two of the mainland New Zealand Dolomedes – D. minor (the common nursery web spider) and D. aquaticus (a fishing spider found hunting on river edges in the lower North Island and throughout South Island). PhD candidate Simon Connolly has spent hundreds of hours in the lab observing mating behaviour in these two species, discovering that while there isn’t evidence of spontaneous male death, there are high rates of sexual cannibalism in one of the species and another peculiar adaptation: genital mutilation. After sperm transfer males break off a section of their genitals, leaving them embedded in the female while the male retreats very quickly to avoid being cannibalised (not always successfully). With this intriguing array of behaviours in mind, I set out to learn more about the Rangatira spider and how it fits in compared to its relatives in New Zealand and abroad.

The Rangatira spider is a roaming hunter, meaning it doesn’t build a web to catch its prey. Instead, it can be found on tree trunks (and in the wood sheds & long drop!) munching on insect prey, especially wētā. Adult females are substantially heavier than males – one female that I weighed on Hokorereoro (affectionately named Porkie) was 5.14 grams! That’s about the same as a rifleman or grey warbler. On average, the females I found weighed 3g, while males were on average 1.8g.

During my time on Maung’re and Hokorereoro I did nightly walks between 9.30pm and midnight, using my head torch to capture reflections from their eyeshine. This is the easiest way to find spiders in the dark. On Maung’re I didn’t have much luck finding spiders on the tracks near the hut – in total over six nights 2 adult females and 7 adult males were located (no juveniles). They were all found on large akeake (Olearia traversiorum) trees, on the ground next to the track, or, in the case of two of the males, on the hut deck waiting to greet us after a long night out searching!

However, on Hokorereoro I was in for a pleasant surprise. Unlike the habitat around the hut on Maung’re, which is quite scrubby, the hut on Hokorereoro is surrounded by lush forest. On my first night out, as I shone my head torch into the trees, I was rewarded with lots of glimmering eye shine – and on closer inspection, many Rangatira spiders. After the initial excitement of the first night, I spent the remaining three nights doing systematic transect monitoring, where I would walk 200 metres along the track towards the summit from the hut, recording spiders along the way. Finding spiders this way allowed me to test out the idea of a mark-recapture programme, which could be a useful way in future to estimate the population size and demography.

Every time I found a new spider I would take a GPS location and note where it was caught, then I’d take it back to the hut to weigh and mark with non-toxic white paint and a unique number. I would then return them back to their capture spots, release them and head off to catch some sleep. On subsequent nights I would search for both new spiders, and anytime I saw a previously marked spider I would record its number. Over four nights, 8 adult females, 12 adult males, and 16 juveniles were observed on akeake, karamu (Coprosma chathamica) and kawakawa (Piper excelsum) trunks. Of those, there were 10 re-sights (32% of released individuals), which was a good indication that a larger scale mark-recapture programme would be an excellent tool for conservation management. The main challenge to spider monitoring is constantly having to dodge seabirds as they come crashing through the canopy in return to their burrows. Rainy weather also makes observations difficult, with droplets resembling eye shine and trees turning into waterfalls.

So, what about sexual cannibalism, spontaneous death and genital mutilation? To describe mating behaviour, I set up pairs of males and females in mesh cages on the hut deck (Maung’re) and in the bird lab (Hokorereoro). There wasn’t much movement until about 9.30pm, when the spiders would start walking around once it was dark. I watched one male court a female by slowly approaching her, waving his front legs as he moved forward. He eventually climbed gingerly on top of her, and attempted to mate for about an hour – but it was difficult to confirm whether he successfully mated as he constantly rearranged himself and didn’t appear to manage to insert his pedipalps (sperm transfer organs). I didn’t observe any sexual cannibalism by the female or evidence of other extreme male mating behaviours, but with only a handful of trials it is too soon to make any conclusions.

Future work on this species is required to reveal secrets about its mating behaviour, but also importantly to learn more about its ecology. A key question regarding their conservation is why – given Dolomedes spiders are well-known to be great ballooners – they are no longer found on Rēkohu or Rangiaotea/Rangiauria/PittIsland. They are likely targets of predation by mice and weka, which may prevent re-establishment, but we need more research to answer these questions.

Thank you to Catherine Beard (DOC) for enthusiastically supporting me to join the trip, to Tara Murray (DOC) for being my invertebrate monitoring partner & for staying up nights to help with spider spotting, the rest of the island team for putting up with my late night disturbances in the hut, and to the Chatham Island DOC staff for facilitating logistics for our trip. Thanks also to the Hokotehi Moriori Trust for putting us up for five nights at Kōpinga Marae while we waited for calm weather to cross to the islands, it was an honour to sleep in such a beautiful place.

Further reading:

• Schwartz, S. K., W. E. Wagner, & E. A. Hebets (2013) Spontaneous male death and monogyny in the dark fishing spider. Biology Letters. https://doi.org/10.1098/rsbl.2013.0113
• Sirvid, P. J., C. J. Vink , M. D. Wakelin , B. M. Fitzgerald , R. A. Hitchmough & I. A.N. Stringer (2012) The conservation status of New Zealand Araneae, New Zealand Entomologist. 35:85-90, DOI: 10.1080/00779962.2012.686310
• Vink, C. J., N. Duperre. (2010) Fauna of New Zealand Number 64 Pisauridae (Arachnida: Araneae). Manaaki Whenua Press, Lincoln, New Zealand.
• Studying the sex lives of spiders: https://www.waikato.ac.nz/news-opinion/media/2022/studying-the-sex-lives-of-spiders

“Something Something Science” is a new, occasional blog series by me, Simon Connolly. I am a (hopefully) final year PhD candidate, and I will be sharing my expertise on insects, spiders and other cool scientific topics. I will also share my opinions on discussions in the science discourse and media, through my perspective as an early career scientist!

You don’t need to be a scientist to enjoy this, and even if you are, you might still learn something! So…scroll on down for the first post in this new series…

Science, Fun and Pop Culture References

“Stop using pop culture references as the first half of the title of your journal article.” This a recent tweet by Michael McCullough, a California based psychologist and author. The response from the twitter scientific community has been overwhelmingly… sarcastic.

Many scientists have replied with their own papers that bear such titles: “#SoMe the Money! Value, Strategy, and Implementation of Social Media Engagement for Infectious Diseases Trainees, Clinicians, and Divisions” and “Sharks on a plane: Large shark fin seizure shines light on shark exploitation.” Others have simply replied with mock titles for articles on the subject: “Stop Making Sense: A Multi-pronged Analysis Of The Futility of Giving Academic Advice Over Twitter”, “I’m just here for the replies: An observational study of the Twitter roast of killjoy professors.”, or the truly perfect “Never Gonna Give You Up: The Use of Pop Culture References in Journal Article Titles.”

Whilst I’m sure we can all agree that these are ‘sick burns’, it does lead to the question of why people feel so strongly about this. The original tweet might seem like a fairly innocuous opinion that has been met with an avalanche of (mostly humourous and well intentioned) responses. I believe that this tweet cuts to the core of a source of tension in the scientific community, and a key question as to how science should be communicated.

But first, let’s talk about science writing, or more specifically journal articles. The journal articles that McCullough refers to are the main way that scientists communicate results, and are read by other scientists when building their own work. They are also, often, quite dry reading. They involve a dispassionate summary of current knowledge; a detailed explanation of how an experiment or study was conducted; a description of the statistics involved; a detailed breakdown of the outcome of those statistics; followed by a robust discussion of the implications of the findings on the scientific world. Can all of these aspects be exciting to the right people? Of course! But there is a reason why you won’t find these articles in the magazine stand at the supermarket, or on the homepage of Buzzfeed. Science writing is often dense and tedious. Poor writing also compounds these problems. Many scientists habitually rely on words like “heretofore’, “moreover”, “correspondingly” and “notwithstanding”, that are used to create overly-verbose, overly-long word vectors that utilise advanced nomenclature and terminology to create a false sense of intelligence and academic rigour, either deliberately or simply incidentally (in other words, scientists use a lot of big words to make themselves sound smart). I am certainly guilty of this too.

The tediousness of scientific papers has created a whole ecosystem of science communicators, journalists, TED talks, podcasts, and blog posts (hello there), which exist to communicate science to a general audience (hopefully without boring them to tears!!). All of this is great, and science communication is an incredibly valuable field! But what about the scientists? What about the people who have to read dozens of journal articles a week, as well as writing their own. Should they not be allowed to have a little fun?

Well, some of us do, by adding little pop culture references to our article titles, and little jokes to our writing. However, others argue that this is unprofessional. These science purists (AKA, the fun-police) argue that the purpose of scientific articles is PURELY to communicate the science, and not to entertain the audience reading it. Many point to legitimate concerns such as excluding those who are not “in on the joke”, an overuse of low hanging fruit (in 2005 there were over 4000 uses of “To be or not to be”) or that there is evidence that articles with pop-culture titles are actually cited less by other scientists (though this could be because the “fun-police scientists” don’t want to engage with these works)! However, I think to dismiss the idea entirely, misses the point.

Something that is fun to read is going to be easier to read. A little joke title can go a long way to getting your audience engaged with the work. A well chosen reference can also be an excellent way to communicate complex information. For example, an article entitled: “The hidden diversity of dimorphic fungal pathogens” sort of tells you what the article is about…however, if you change the title to “Fantastic yeasts and where to find them: the hidden diversity of dimorphic fungal pathogens” the audience immediately knows what the paper is about! We’re going on a fantastic yeast hunt, and honestly, who wouldn’t want to!?

But, the other thing to consider is that scientists are human. We like fun, often silly things. We want our jobs to have moments of levity, especially during tasks that are often bland. Pop culture is also a huge part of who many of us are, and speaks to why we became scientists in the first place. I would be a liar of I said that part of the reason I want to complete my PhD is so I can say “I’m a doctor, not a…” at every possible opportunity. And I think many of my peers are inspired by scientists in pop-culture (both fictional and not). To ask for the wholesale removal of these references from people’s work is doing a disservice to the fun-loving, science-loving people who write them.

But of course: that’s just like, my opinion man!