Week 2- 26/10/10 - 2/11/10 (Part 1) Bird Surveys End, and The Trials of Taxonomy

Shy Heathwren

By this point we were halfway through our bird surveys, having covered two-thirds of the sanctuary and hitting the plateau of our species-area curve. We had long since abandoned the Black-eared Miner surveys, partly out of boredom, partly a desire to apply ourselves to other endeavours, and finally because there were other volunteers to take up the baton. There was also the advent of pitfall trapping to look forward to, not least because we would finally be nailing down some specialist arid-zone herps and mammals. Midway through the week, we were given a small taste of what could be. An old trapping site, situated in a patch of low-growing Eremophila and saltbush scrub, had to be taken down. While we were there, we spotted what looked suspiciously like a firetail skink (Morethia ruficauda), which would have been a new record for the sanctuary, and a range extension of some 2000km. Given the obvious attraction of verifying such a sighting, we were persuaded to open the traps for one more day.

As it turns out, we didn’t get the desired skink, but we did trap a few other species: a male Painted Dragon (Ctenophorus pictus) in all his dazzling finery, and some Ctenotus skinks: C. atlas, C. regius and C. schomburgkii. This last one, in particular, was a poignant demonstration of the importance of having herps in the hand: many skinks, and indeed a lot of reptile species, are distinguished by very fine-scale [and often subjective] features, ranging from details like the numbers of scales on different parts of the body and nature of keeling on the subdigital lamellae to such absurdities as the extent of a notch on the rostrum or the manner of contact between head scales. Involving terminology like ablepharine, mucronate, carinate and callose, it can all get a little befuddling for the uninitiated.

In addition, many species are part of large complexes, their members distinguishable only by the presence or absence of one scale here or one groove there, and at times not even through any morphological means- some are split along genetic lines, taking into account genetic differences between populations in the absence of any actual morphological variance. Colour and pattern are of little use; many species can vary significantly between populations and individuals, and still remain the same species, whilst individuals of two different species, say Ctenotus strauchii and C. schomburgkii, can occur sympatrically and look nigh-identical, but will be different due to one having nasal scales separated and the other in contact. It is often quipped that taxonomists are a different breed of scientist; I am at times of the belief that herpetological taxonomists are a different breed of taxonomist.

The inevitable question is, now that we’re on the level where we’re distinguishing species, not through any tangible morphological difference but on a molecular basis, and that occasionally right down to genetic differences of micro-populations within a larger population, where does one draw the line? Taxonomists [and I consider myself one] have yet to devise a proper answer, suggesting that there is no standard currently in place, nor has any significant union or academic body risen to seriously consider the issue. The truth is, so idiosyncratic a field is taxonomy, that to expect consensus out of what is essentially a loose collective of disparate individuals, each thoroughly self-absorbed with conundrums like the distinguishing textures of scaling on a butterfly’s thorax or the beak diameters of different reed-warblers, is to expect the impossible.

To be a taxonomist is to have a penchant for being obsessive, to be able to immerse oneself so thoroughly into deducing and naming the full and accurate diversity of species within one’s organismal group of specialty [some taxonomists build entire careers out of working on just one family or even species], that frivolities such as outside opinion are relegated to a secondary concern. It is easy to create a bubble around one’s work and self and get utterly lost in a world of micron and single base-pair-level painstaking obsessiveness; a classic ‘can’t see the woods for the trees’ scenario, except in this case one is so enamoured with the thirteen different lichens on one branch that one forgets there is even a tree, let alone an entire woodland.

I will hasten to add, lest I be accused of painting an overtly negative picture of taxonomists, that such methodical compulsiveness is not necessarily a bad thing. To say taxonomy suffers from a lack of definition regarding what is actually a species is to ignore the fact that there are millions of species out there, probably more than we will ever know. Nature is no respecter of boundaries; cut anything down to a certain level and grey areas quickly appear, if not ahead, then in the wake. If we do not yet know where the threshold of the species level lies, maybe it is because Nature itself does not know. Maybe there is no difference. Maybe in the grand scheme, the difference between Ctenotus schomburgkii and C. strauchii, one mealworm to the next, myself and the next person, is no more obvious to Nature than that between a cat and a cabbage [with concession, of course, to reproductive viability!]. Perhaps in the end, all that really matters [and let’s face it, it really does in taxonomy] is a name to a face. In that sense, one cannot blame taxonomists for operating within their own little cells of reality, progressing and developing in their own way but largely independent of any wider scheme. In a world where to be fundamental is to be profound, where even the finest workings of matter itself are yet to be fully understood, taxonomists’ strive, like all scientists, to achieve comprehension and organisation. The complexity and diversity of a world that appears, at times, designed expressly to thwart total comprehension, fails to neither frustrate them nor blunt their efforts. In this, they and their endeavours are to be lauded.

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White-browed Treecreeper

We were on the home stretch for surveys, but the ticks, though less frequent, kept coming. On the same afternoon we spent searching for our mystery skink, we were checking traps when Jeremy raised the alarm: he had seen another Red-chested Buttonquail. While the chief ecologist sauntered over for a look [she had never seen one before on the sanctuary], I continued to process my trap line; no matter, I had seen this one. My complacency, however, was to be punished in the most predictable fashion: seconds later, Jeremy called out again: “It’s not a Red-chested, Russ, it’s a Little!” Stunned by the revelation, I sprinted across the thorn bushes, dreading but knowing the inevitable: by the time I arrived, the bird had vanished into the scrub. I searched the vicinity to no avail; I had missed my first Little Buttonquail (Turnix velox). So a tick for one but not the other; there would be a couple such incidents through this trip, either because we weren’t together or just unlucky. We almost had a repeat incident the very next day: out in the fire scar marking trap sites, we both happened to be looking in different directions and preoccupied when the chief ecologist said “White-fronted Chat (Epthianura albifrons)!” I got my head out of the car window in time to see two birds, their white chests and black bands distinctive, flying into the sun. Jeremy, outside of the car, got a better look, and so it came to pass that we saw one of the commoner southern outback birds, but were only afforded a brief glimpse. A believer in omens would say we’d hit the point where our luck had run out; a pragmatic birder would note that there is no luck, just nature, and cynical birders like ourselves just live by the simple mantra: Birds would be awesome if they weren’t such pricks.


Other things showed up in these last few days of bird surveys, not necessarily new but nonetheless notable: Sacred Kingfisher (Todiramphus sanctus), Striped Honeyeater (Plectorhyncha lanceolata) (above) and Varied Sittella (Daphoenositta chrysoptera). Familiar birds abounded: Australian Ravens (Corvus coronoides) were abundant, as were Galahs (Eolophus roseicapillus), Willie Wagtails (Rhipidura leucophrys), Black-faced Cuckoo-shrikes (Coracina novaehollandiae) (right), Rufous Whistlers (Pachycephala rufiventris) and Grey and Pied Butcherbirds (Cracticus torquatus & C. nigrogularis). Other things present but less abundant included Weebill (Smicrornis brevirostris), Striated Pardalote (Pardalotus striatus), Yellow-rumped Thornbill (Acanthiza chrysorrhoa) and White-eared and White-plumed Honeyeaters (Lichenostomus leucotis & L. penicillatus). As for new things, we saw our first Southern Whiteface (Aphelocephala leucopsis) on the base itself, while another sojourn in the fire scar brought us our first Black Honeyeater (Sugomel niger).