Otterman speaks... (2003-2007)
Weblog about cycling, macintosh, natural history and life in Singapore.
Otterman - Blog Home

Archives - Blog's RSS - Comments RSS - LJ - Email me - All my blogs - About me: 2004 - 2002

Make a permalink or URL tiny:
Blog email subscription

Enter your email address to receive the previous day's posts:

Categories

Mac and the Internet - NUS
Cycling - Life in Singapore - Meow
Singapore Naturalist - Mangroves
Science - World - Museum
Movies - Literature - Travel

Biology module blogs:
Biodiversity (Year 1)
Ecology (Year 3)
Structure & Function (Year 3)
Marine Biology (Year 4)
Natural History Blogs:
The Biology Refugia
Raffles Museum Toddycats
Intl Coastal Cleanup Singapore
Labrador Park
Pulau Ubin Stories
Pulau Hantu
Yesterday.sg
Cycling in Singapore
Mac Meetup Singapore
Aboard the Götheborg
Otterman Projects
Herpnet
Zendogs/Wheels are Turning
Hopea sangal


Raffles Museum Toddycats!

Pedal Ubin!
Pasir Panjang Heritage
Raffles Museum Internship
MR-BT Briskwalkers



Mac Meetups
Singapore

Some of my kakis

Kakis at home
Lekowala
Ad & Jen
Inertia is a Sin
Halfway between the gutter and the stars
Lost in the Jungle
Dawn, Cat Welfare
Compulsive Maniac
Deadpoet's Cave
Rambling Librarian
Cooler Insights
Pencil Shavings
Moi-Carine
NatureAntz
Ling the Merciless
Philosophize Me Jelly
Dewi A

Kakis overseas
Alvin - Beijing, China:
* Alvin's spiel
Kevin - Buffalo, NY:
Theory is the Reason
Bonny - HCMC, Vietnam:
VietStuff
Jac - London, UK:
Dogged Wanderings
Jasmin - NY, NY:
The Worsted Witch
Marcus - Shanghai, China:
You only live once
Tse-Lynn - Wilmington, NC:
Musings of a barefoot traveller
Jani - Newcastle, UK:
Salted & Fried

Seow Hwa's
The Ice Cream Gallery

Local reads
Commentary Singapore
Singapore Surf
Tomorrow.sg
Screenshots

Resources
SinGeo
Museum Roundtable
Science Daily
Environmental News Network
National Geographic News
New Scientist news
Nature News
Google News
BBC
Resource Shelf
The Unofficial Apple Weblog
Boing Boing
Wired
The Daily Show
www.flickr.com
This is a Flickr badge showing photos in a set called My Handphone Photos. Make your own badge here.
Books


Made on a Mac with
Claris Home Page 3.0.
Blog engine: Samizdat,
based on PHPosxom,
based on Blosxom.
Updated with TextWrangler.

Creative Commons License
© N. Sivasothi, 2003
This work is licensed under a
Creative Commons License.

Subscribe with Bloglines

Otterman speaks...

Cycling, macintosh, natural history and life in Singapore - Archives

List of Categories : travel * museum * cycling * Singapore Naturalist * science * kakis * mangroves * movies * mac and the internet * meow * NUS * life in Singapore * lit * world *

Mon 29 Aug 2005

Potter wasp at the door, Part II

Category : Singapore Naturalist

Sat 27 Aug 2005 morning - With at least three large caterpillars inside the second cell (see Part I), its filled it to the brim. Why hasn't the second cell been sealed? The first one was sealed by two days. It has been three days already.

The caterpillar nearest the mouth of the cell is twitching energetically, much more than expected. Not a pretty sight!

Sat 27 Aug 2005, after 3.00 pm - That afternoon, the door is opened to reveal a fallen caterpillar just below the nest. Unfortunately it is stepped on, bleah! The heavy twitcher must have been resistant enough to the venom to twitch its way out of the unsealed cell!

Early that evening, after 6.00 pm, I realise the second cell seems only to contain one caterpillar - a far cry from the filled nest of the morning. Another caterpillar must be missing!

Sure enough, more than a metre away down the corridor, another caterpillar is discovered, surrounded by ants. What's going on?!

All the colours observed in the nest chambers are explained by the body patterns of the caterpillar. The green colour, however, is special and comes from the fluid-filled enlargement of the thorax. The thorax is the predator's usual point of attack, so presumably this deformity is the result of the wasp's paralysing injection of venom. I pop the two caterpillar bodies into a sealed plastic bag and then into the freezer soon after as ants are swarming around it - the bodies are at least a few hours old.

Did the energetically twitching caterpillar finally fall out of the cell by twitching hard enough? This seems likely, given that the caterpillar was found just below the nest.

Did the other caterpillar twitch-crawl all that way down the corridor? Could it have been that resistant to the paralytic wasp toxin? Possibly.

Or could another potter wasp have raided the open cell, but lost its grip of the heavy caterpillar on the way out (I don't know if this happens with potter wasps)? Could the returning mother have dropped a fresh caterpillar? I favour the idea that the caterpillars escaped. Ants would have got to them both in the end - they were doomed once the potter wasp grabbed them from their feeding frenzy off some leaf.

Why the nest had not been sealed remains a mystery. The mother wasp had all of Saturday morning and afternoon to seal the nest but didn't. Has the nest been abandoned or the mother killed?

Sat 27 Aug 2005, after 7pm - The cell seems rather empty; certainly there is less than half the prey of the previous night. If the mother does not return, the grub that hatches will go hungry after devouring the first caterpillar.

I peek into the nest and see a sliver of a white larva. Foreboding thoughts of an abandoned nest make me think of the maggot of a flesh-eating fly, freshly hatched out to devour the remaining caterpillar and the wasp egg! Then I realise maggots are not usually solitary and feed on dead meat not living flesh - well most of the time at any rate; I am being silly.

Then it dawns on me, that Saturday night - I am looking at the newly hatched potter wasp larva of the second cell!

It's so small, and is dwarfed by the lone snack in the cell, the caterpillar that did not get away. But being an insect larva, it will feed voraciously and grow in leaps and bounds. In the adjacent cell, is its sibling, who must be munching away in programmed determination.

The escaping caterpillars have left the potter wasp trapped in a cell with insufficient food. It could starve to death after it has eaten alive the remaining caterpillar.

Posted at 2:42PM UTC by N. Sivasothi | permalink | , .