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Monday, 9 April 2012

Storing dead specimens

There is a time and a place for taking animals, killing them and storing dead specimens, but as a rule, I think it's best to leave things where they are. I will find them, catch them if I really need to, but where possible, I try to let them go where I found them.

Flinders ranges dragon: note its camouflage.
I have a few dead animals in Australian Backyard Naturalist: one was a mummified lizard that I found in my garage; another was a freshly dead bandicoot which will appear in the next blog entry in a starring role.

Notice the pattern there: I collected them dead. There was also a huntsman that I found dead: I suspect that somebody had sprayed it, because it was freshly dead and undamaged.  I will come back to that in a moment.

Under normal circumstances, when I found a dragon like the one on the left, I would leave it where it was, photograph it (as I did), and walk off.

In this case, I was with a party in the Flinders Ranges who would be interested, and I needed a close-up shot taken it show how a lizard is held safely, gently and firmly (that's safe for the lizard: you can't see the tail in the lower shot, because it's being used to lash me!

Under normal circumstances, this next shot is far nicer than a dragon in a cage or in a pickling bottle!
One of our local water dragons in Sydney.
Would you believe that this was a dead cicada, found on a path?  Well it was!

There are times when it is right and proper to collect live specimens to kill and store for reference or study purposes. If you end up working in this area as an adult, then you will spend a great deal of time catching and preparing specimens. As a hobbyist like you, I urge you to just collect with care and thought. Here is what can happen when collectors go mad.
Hunting the last great auk
We know a great deal about the last of the great auks. These Icelandic sea birds were collected to death, so poor hunters could sell the bodies to rich "amateur" collectors. A set of islands called the Geirfuglasker Skerries, sank after volcanic activity in 1830. This left the auks with just a single home, the island of Eldey, off Iceland. The collectors kept collecting.
On June 3 1844, an expedition of 14 men sailed to Eldey. Sent by an Icelandic bird collector named Carl Siemsen and led by a Vilhjälmur Hakonarsson, they wanted to get specimens before the last auks died out.
Only three men actually landed on the island: Sigurör Islefsson, Ketil Ketilson and Jón Brandsson, and they only found two great auks. Both birds ran away, but slower than a man could walk. Jón cornered one of them and Sigurör trapped the other. Ketil walked back to the place where the birds had been, and found an auk egg, but it was broken, so he left it there.
The last great auks left Eldey dead. Vilhjälmur Hakonarsson went back in 1846 and again in 1860, but he saw no great auks on Eldey. A species had been snuffed out in the name, not of science, but to feed an amateur mania for unusual and rare specimens.
Sadly, I couldn't get an auk to come to the camera, but here are some puffins from Lunga in the Hebrides.
If you are collecting lots of moths or butterflies, you will need a relaxing jar, a spreading board, storage boxes and entomological pins, but I won't deal further with those here, because I have little experience with them. I can, however, discuss relaxing as I practised it on my dead huntsman spider.

When thing die, muscles tighten, the body contorts, and it generally ends up drying into a contorted shape. The spider was beginning to contort, so I put it in a jar that contained a wet tissue and a piece of aluminium foil. Sorry, I wasn't planning to write about this in the book, so I didn't photograph the jar.

Anyhow, the idea was to keep the spider in 100% humidity until it became loose, so I could then pin it into place on a piece of foam like this. None of the pins goes through the spider: they all just hold the limbs in place while it dries and "sets".

Notice how the pins support and constrain the limbs, so they dry and set in a like-like pose.
You can keep dead insects, pinned in drawers or boxes, but if you want to preserve them, you will need to seal the containers and keep some mothballs in there, or other insects will eat your prizes. Another possibility is to use a preservative solution.

The most common solution is 70% alcohol, a mix of 70 mL of alcohol (methylated spirits) and 30 mL of water (scale this up or down, keeping the proportions constant). Over time, some of the alcohol will evaporate, so if you need to keep your specimens for a long time, you need to pour off all the liquid and replace it every couple of years.

Some specimens slowly bleach over time in 70% alcohol, but I cannot say if this is caused by light or the fluid. One drawback with methylated spirits: it contains some poisons to stop people drinking it, and when you add water, it often goes cloudy for a while, but after a while, it goes clear again.

Photographs are probably a better way to record your finds. Just ask this centipede, which I brought inside and then released under its flower-pot where I found it.

Anybody who knows my Facebook page will recognise this beastie.

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