Field trips for Townsville wildlife enthusiasts

people on dam wall
The beginning of the Birdlife Townsville walk at Ross Dam

The period between Christmas and Australia Day is a quiet one for many organisations but everyone seems to be gearing up again now.

Birdlife Townsville (formerly, I think, the Townsville Region Bird Observers Club, which was cumbersome but accurately reflected their focus) didn’t slow down at all for January: their calendar lists nine events for that month, which is close to average. They are a keen lot!

I was invited to their “Ross Dam Survey” on January 17th and enjoyed it. A dozen of us met at the Dam carpark, drove along the Kelso side of the dam as far as we could and then walked, first along the dam wall and down beside the creek which enters the head of the dam. There were, of course, lots of water birds – ibis, spoonbills, egrets, cormorants, pelicans, etc – but many other species were sighted and counted in the two and a half hours. I learned a lot, not least that my bird-spotting skills could improve with more practice like this!

Wildlife Queensland has begun announcing its monthly walks. The first is to Paluma Dam (a lot further away than Ross Dam but very beautiful) on February 21st.

Both of these associations welcome non-member as participants in at least some of their events, but encourage membership. And why not, when the clubs do so much for conservation?

Townsville’s record-breaking 2015 rainfall

I have been grumbling for months about how dry Townsville has been in the last year, and the annual figures are now in: 2015 was the driest year on record, with just under 400mm compared to our average of 1135mm and our highest-ever of 2400mm. We have just continued the pattern by completing a dry January, 77mm compared to an average of 270.

tsv-rainfall-low-highMy figures are from the BoM’s Climate Data Online for Townsville airport, here (I have rounded them off to the nearest whole millimetre). Looking at the annual rainfall totals in that table, a pattern pops out: four-digit and three-digit totals don’t alternate randomly but come in clusters, 3-5 of each at a time. For instance, 2001-06 were all below 1000mm, while 2007-12 were all above it. Extracting the first and last columns and colouring the totals blue for wet years and brown for dry years (see table at left; click on it for a larger version) makes the pattern more obvious, and highlights one other quirk: a run of dry years is sometimes interrupted by a single wet year (e.g. 1968 and 1981) but the converse isn’t true.

tsv-rainfall-low-mid-highI also divided the range of annual totals into three: close to average (1000 – 1300 mm), wet years (more than 1300) and dry years (less than 1000). Colouring them appropriately brings out another feature, showing just how rare an “average” year is: only one year in five is within that zone.

Monthly rainfalls also vary wildly. I could repeat the same exercise for  (e.g.) January rainfalls, where the average is 270mm but the actual figures vary from a mere 9mm to 1142. We can’t even say that a wet January is particularly likely to be followed by a wet February and March. Sequences like 85 – 549 – 53mm (2002) and 19 – 316 – 73mm (2003) are not uncommon.

In fact, we have to realise that an average month or year is not at all normal.

Climate is what we expect, weather is what we get

So can the statistics tell us anything useful at all? Well, yes. They can obviously say things like, “Yes, 2015 was much drier than usual. It wasn’t your imagination.” They can also warn us not to expect an average month or year, something that long-term residents are vaguely aware of but many newcomers are not.

More subtly, they can warn us that we are getting a run of extremes and should be concerned by them. As Hansen warned us some time ago, every broken record carries the fingerprint of climate change – not necessarily caused by climate change, but made more likely by climate change.

They can show us, too, how our climate is changing over the long term – and those trends are likely to continue into the future, over at least a similar time-frame. “Climate is what we expect, weather is what we get,” (the quote is well known but its origin is obscure) and in those terms it’s clear that we need to look at periods of more than ten years.

Fortunately, we have done that – well, the BoM has, and has made the data available to all of us online. In particular, their trend maps make long-term changes beautifully (scarily?) clear. Here, for instance are the national rainfall and average temperature trends since 1970.

rainfall-trends

temp-trends

Food for thought – especially the extreme drying trend down the East coast, where most Aussies live. For more detail, follow my link to look into different regions, seasons and data sets.

As for Townsville, all we know is that we don’t know what to expect. The BoM made some educated guesses for the Townsville Bulletin’s January 4 article about our meagre 2015 rainfall but most of the article was concerned with very short-term forecasts. The BoM’s Outlook page suggests that the North will be drier and hotter than average in the next few months, Feb-April, but we shall have to wait and see.

Green Path is now mobile-friendly

If you have noticed that the blog looks different, it’s because I have just installed a new WordPress theme. The object wasn’t to change its appearance but to make it mobile-friendly. If you play with screen sizes and zoom in and out on your desktop screen, or open it on your tablet or phone, you will notice the difference. You may also notice some glitches – sorry! If you do, please let me know so that I can fix them.

Words we need: Mathom

As we move, ever so slowly, towards a sustainable society, it is gradually becoming clearer that we in the West just have too much stuff – too many material goods, to be more formal – to be able to achieve long-term balance. ‘Mathom’ is a word which can help us reduce our excessive consumption.

It’s a word which goes all the way back to Anglo-Saxon times and re-entered the language via Tolkien:

“It was a tendency of hobbit-holes to get cluttered up; for which the custom of giving so many birthday-presents was largely responsible. Not, of course, that the birthday-presents were always new; there were one or two old mathoms of forgotten uses that had circulated all around the district…”

— J.R.R. Tolkien, The Fellowship of the Ring, Vol. 1

As Wikia tells us, “Mathom” was the hobbits’ term for anything which they had no use for but were unwilling to throw away. A Tolkien Mathomium has much to say on the real Anglo-Saxon origins of “mathom”, the traditions behind it and the “comic irony” intended by Tolkien who knew exactly what he was doing when he re-made Anglo-Saxon “mathum” into Hobbitish “mathom”. It’s fascinating stuff (for word-nerds, at least) but the modern usage is what we’re really here for. Urban Dictionary defines it well:

Mathom: A regift. A relatively trivial object that has repeatedly been given as a present.  …
[Mathoms] most likely persist because they are slightly too valuable or unusual to dispose of outright or give to Goodwill, yet have such limited use or appeal that few wish to retain them. Modern-day candidates for mathomhood are commonly visible in catalogs for novelty electronics, pop art, junk jewelry, and sports memorabilia, as well as in roadside “local” gift stores.

Elaine St. James, in Simplify Your Life (1994) uses it more positively:

When packing, start with treasures such as vases and art objects (of course, these are now going into the mathom box, […]) … Now, when special occasions arise at which a gift would be appropriate, I search in our closet for a suitable mathom. I’ve also let my friends know that they are free to pass on (or possibly fob off) these “treasures” to someone else whenever appropriate.

I could say more about why and how we should reduce our consumption but Madeleine Somerville has just said most of it for me – starting with the headline, Yes, you recycle. But until you start reducing, you’re still killing the planet –  in the The Guardian so I will finish with a word from one of Tolkien’s contemporaries. It’s better known and perhaps even more important to our future: Enough!

enough

Bookshelf entomology

Everyone knows about bookworms, even if all they know is the name, but bookworms are not the only small wildlife found in bookshelves, particularly in the tropics, as a recent bout of librarianship associated with repainting a couple of rooms has demonstrated to me very clearly.

mud wasp nests on book
Exhibit 1: Wasp nests

Wasp nests like these were by far the most common sign of insect life in our bookshelves. Female mud-dauber wasps (Sceliphron sp.) construct a cell, lay an egg inside and provision it with food for their larvae then, if they can, repeat the sequence nearby. A string of cells like this will have been constructed in a short time (days or weeks) by a single wasp and, if all went according to plan, her children would have emerged and followed suit.

The empty cells stay there for ever but don’t cause any real harm. They are just dirt, and nearly all of it will brush off. The easiest prevention is to push books all the way to the back of the shelf, making the gap too small to be tempting. The wasp will probably build a cell in a corner of the shelf instead.

Exhibit 2a: Resin bee nest
Exhibit 2a: Resin bee nest
Exhibit 2b: Resin bee nest occupied by mud wasp
Exhibit 2b: Resin bee nest occupied by mud wasp

Mud wasp nests are so common around our house that we hardly notice them until they do something odd but the resin bee nests did surprise me.

The pine bookshelves are adjustable, via a double row of holes about 5mm in diameter down each side for the shelf brackets. The empty holes seem to have been just right for our Fire-tailed Resin Bees (the second species described here).

In turn, the empty resin bee cell seems to have been just right for a tiny mud wasp to build its own cell. We often see tiny nests like this in odd nail-holes and screw-holes and, less often, in resin bee nests outside the house.

The resin bees are not doing any harm here except that the shelves are no longer so adjustable as they were meant to be. The resin is very tough, so removing it may mean drilling it out.

book eaten by silverfish
Exhibit 3: Silverfish damage

Our books don’t suffer as much from silverfish here as they did in Melbourne, I think because our climate is (usually) too dry for their liking, but this is their typical handiwork (mouthiwork?): superficial nibbling at the cover or dust-jacket, sometimes extending deeper into the bulk of the book. This damage may actually have occurred in Melbourne – we have had the book that long.

book attacked by borer
Exhibit 4a: Bookworm

The Britannica notes that a bookworm is, “any insect (e.g., moths, beetles) whose larval (or adult) forms injure books by gnawing the binding and piercing the pages with small holes. No single species may properly be called the bookworm because a large number of insects feed upon dry, starchy material or paper and may damage books.”

More specifically, however, bookworms are the larvae of beetles. Their damage is more distinctive than they are: tunnels one or two millimetres wide, often though book covers and sometimes through the pages, with a scattering of sandy droppings tending to fall out when the book is handled.

They are the most destructive of our book pests, and a book has to be really special before we will go to the trouble of trying to save it from them. They are not very choosy and it is obvious that one of ours veered out of its book and into the side of the bookshelf.

wooden shelf attacked by bookworm
Exhibit 4b: Bookworm, lost

Online references such as “Bookworms: The Most Common Insect Pests of Paper in Archives, Libraries, and Museums” compiled by Dr. John V. Richardson Jr., PhD, Ecological Informatician (nice specialisation!) list various other pests but we don’t see many of them.

Spiders, often Daddy-longlegs, sometimes lurk in corners of the shelves but do no harm at all; “booklice” (Psocoptera) don’t seem to be a problem here (again, probably because our climate is too dry) and cockroaches don’t go near our books except by accident.

Dr Richardson also mentions termites and these can indeed be a problem in North Queensland. There is a wonderful passage in Alex Miller’s Journey to the Stone Country in which visitors to an abandoned homestead investigate a bookcase and find that it has been transformed into one solid mass of termite-mound.

I will leave you with that thought as I return to my re-shelving.