Chilean Temperate Arthropoda 2007, Oncol Park

Expedition, January 2007
By Dr. Elizabeth T. Arias & Professor Kipling Will
Oncol Park

Oncol is a privately-operated forest park in the heart of the Valdivian coast– in fact, it’s just north of the city of Valdivia. This chunk of land is owned by a forestry company, with a few patches of old-growth forest set aside for hiking, birdwatching, and other forms of ecotourism. The park is also close to the Pacific coast, so it’s the perfect place for us to settle down for four or five days and collect. We’ll spend a few days sifting soil and fogging trees in Oncol, and a day or two collecting at Curiñanco (a beautiful forest preserve overlooking the ocean). So far we haven’t found any of our hoped-for weird scorpionflies, but there have been lots of great beetles and other arthropods! Our accommodations are also the best yet– we’re staying in a big, clean, multi-room cabin with a working fireplace, hot showers (!!!) and lots of room to set up our makeshift laboratory. Since we have a long stay and plenty of room to work, we can start sorting out our samples from the fogging. This is one of the most exciting parts of the expedition, like opening presents– you never know what’s going to be in the next sample, and there’s always something weird and new. This year’s “weirdo” is a leiodid-like beetle that nobody can identify… which is really saying something, given how many beetle experts we have on the team.

The forest in the foreground here is part of Parque Oncol, and Valdivia can just barely be seen at upper right. Can you find the canopy-fogging team in this photo?

At Oncol we spent a lot of time in the old-growth forest, doing “mini-fogging” on fungusy logs. This is a fantastic way to catch leiodid beetles– all you have to do is find the right kind of fungus, and the beetles come raining down. Ainsley is using an aspirator to suck up tiny beetles. (many of them are too small to pick up by hand)

Results from one of the mini-foggings: a sheet covered with leiodids! (this is as thrilling as it gets when collecting teeny-tiny beetles)

… but then, it’s not such a surprise that you’d get a lot of beetles, when you’re collecting from fungi this big! This is one of the biggest bracket fungi I’ve ever seen.

At the other end of the fungal size spectrum are the “fruiting bodies” of slime molds (this is a tiny “garden” of myxomycetes growing on the end of a log). Just as at Nahuelbuta, these little fungi were being nibbled by the leiodid beetle Neopelatops.

Even in the middle of summer, decaying logs provide enough shelter and insulation to preserve small pockets of cool, moist semi-aquatic habitat. This allows amphibians (like this frog) to live in the forest without drying out.

Some of these microhabitats are wet enough to be considered completely aquatic– the scirtid beetle larva in this photograph has the same kind of underwater breathing adaptations as beetles that live in ponds and lakes.

Some of these microhabitats are wet enough to be considered completely aquatic– the scirtid beetle larva in this photograph has the same kind of underwater breathing adaptations as beetles that live in ponds and lakes.

In slightly less moist areas (but still cool and dark), we find strange creatures like this opilionid. This is the same kind of animal as the “daddy-long-legs” we see in California; for some reason, the Chilean ones are much more elaborate and weird. The green, stripey area of this opilionid’s body puffs up when it’s disturbed, and the yellow spots are actually some kind of defensive secretion.

We fogged a few trees here as well. Andres (fully suited) prepares the fogging machine…

… while Juan-Jose checks the wind speed with an anemometer. We can only fog when there’s little or no wind.

Bill and John collected small beetles by beating vegetation over a sheet, then aspirating the more desirable insects.

In the fogging, we found some much larger insects– this phasmid (a kind of stick insect) fell out of one of the trees.

As usual, there were Liolaemus everywhere. A brightly-colored lizard (male, most likely) basks in a sunny spot.

We also found some less colorful macrofauna–for example, this leopard slug captured by Bill, tentatively extending a pair of slender eyestalks.

Back at our temporary headquarters in Oncol, we used whatever tools were at hand to sort our catch from the fogging.

Juan-Enrique is not, in fact eating soup– despite the spoon.

At least, it’s not the kind of soup you’d probably like very much. Unless you’re an entomologist. There’s a plump, juicy stag beetle visible just above the handle of the spoon, plus lots of other small, many-legged creatures.

Before leaving Oncol, Gabriela and Ainsley gather ‘round the fireplace to share photographs and edit files for this website. After four days with no electricity, we had to charge our computers from a gas-powered generator before we could work on material for the website.