Animal record breaking

So far I’ve been very good at not linking activities at the Grant Museum to the Olympics. While I’m out here on ecological fieldwork in the remote northwest savannahs of northwest Australia, The Games have been very far from my mind. However, the phrase “new record” has been bandied about quite a lot here this month, and now I find myself writing a post that has nothing to do with the Olympics, but I’ve now already mentioned them three times. I appear to have jumped on the bandwagon of making a spurious link – something that everyone seems to be doing these days. Apologies.

I’m currently working with a small team of ecologists catching animals on wildlife sanctuaries and cattle stations to monitor the effects of cattle and fire management on the ecosystem. This year we’ve caught a fair few animals in areas in which they’ve never been seen before. The excitement of being part of these new records is definitely personally valuable, but I’ve also been thinking about how these single pieces of data are potentially more valuable than all of the other single animals we catch.

We use both baited traps and pitfalls to survey which species of snake, small mammal, lizard and frog live in a given area (and then re-release them). Over the trapping season we might trap at a hundred sites and catch a thousand animals. Each of those represents a tiny portion of the massive sample sizes needed to answer any of the questions that are being asked. A single data point normally doesn’t change anything on its own. New records on the other hand are a single piece of information that stand alone as undisputable facts.

In the study of small populations, or species which are cryptic (small, nocturnal, hard to see critters, for example), absence can never be proved – we can only say that a species has never been recorded in an area; we can’t say that it doesn’t live there. This is why it’s really hard to pinpoint when a species goes extinct; an absence of records for a long time only allows zoologists to presume that something is gone. While it’s pretty unlikely that (non-birdy) dinosaurs still roam the Earth (though people who’ve read Conan Doyle’s The Lost World or came to see The Valley of Gwangi last week at the Grant Museum may think differently), the survival of things that haven’t been seen for tens of years or even a few years are much more questionable.

This month we’ve found northern brown bandicoots in locations in which they’ve never been seen before. This species isn’t particularly rare, but the new discoveries could be a sign that things are improving here. It might be a combination of the new fire management regimes, good rain conditions and changes to cattle intensity that have allowed the bandicoots to spread anew to these territories, or they might have been there all the time and just hadn’t been caught before. It would be nice to think that the new records suggest the former, but on their own they can’t discount the latter.

Another ecologist and I went out with spotlights last weekend to see what we could find wandering around at night near the main homestead here. We came across a short-eared rock wallaby – something that have never been seen on that set of cliffs before, despite regular excursions to the same spot. While the single piece of information is certainly not ground-breaking – the species is found all over the property – being part of its discovery came with a definite sense of achievement. When I came here last year, I was told that rock wallabies have never been found on that range. Now we have proved their presence (and confirmed it since with remote cameras).

This week we’ve caught a couple of lizard species that aren’t recorded this far north. It would probably take a few more records over an extended period of time to officially extend their range in the field guides, but these single data points could begin the process of proving that the species does live beyond its known bounds.

Although on their own they are all miniscule little facts that no-one will read about and won’t change much at all, for me, as much as I enjoy the Olympics, I expect they’ll be the most exciting records of the year.