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MEANWHILE, BACK AT THE LAB
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The Insectarium's rearing room is strangely Amazon-like. The air is warm and humid. Spiny stick insects peer from leaf clumps. Katydids chirp and trill. Mantises snatch and devour futilely buzzing flies. And quirky entomologists (myself included) explore narrow trails through tall dense cage shelving. |
| A Rough Start: The colony fragment collected March 1992, though badly stressed, offered an unplanned opportunity to develop and practice captive management techniques. I was well aware that my colleagues would not look favorably upon my efforts if dangerously venomous ants were to escape and run amuck in our work area. I also knew that bullet ants are strong-bodied, adept climbers, far-foraging and thus prone to jailbreak. It was critical that all housing components fit securely and be built from ant-proof materials. |
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| Quickly improvising, the remaining ants were placed in a large tank lidded with plate glass, offered various food and trial nest chambers. After about a month, the sole wingless queen died, eliminating any possibility of colony growth. Three months later, only a few dozen workers remained; these were euthanized by freezing to make room for my next attempt.
Taming the Beast: The 800+ ant colony collected June 1992 obviously required substantial living quarters. I also wanted to keep the nest humid for brood rearing and the foraging area dry to retard debris decomposition. With these needs in mind, I adjoined two 40-gallon tanks, one for nesting and the other for feeding. The tank tops shared a crude but durable plywood cap. This contained an ant crawlway, accessed by wooden ramps, and screened panels for ventilation and moisture control.
In the nesting tank, I created a roomy, low-rent condo by horizontally stacking five glass sheets spaced to accommodate ants and brood. I provided naturalistic, non-muddying, nesting substrate by mixing moist sand, fine gravel and shredded cypress bark mulch, and partially backfilled this material into observation nest spaces.
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When first released, the ants were disoriented for about a week, but eventually settled within the glass sandwich and constructed characteristic nest chambers. For many months thereafter, we enjoyed watching bullet ant colony life and brood rearing in the upper tiers. Unfortunately, ants residing in the lower spaces were difficult or impossible to observe. |
| A tall brick stack in the foraging tank provided an easy-to-reach thus safer-to-service feeding platform. Experimenting, I found that bullet ants strongly preferred sugar-water to honey. This was offered spiked with a pinch of vitamin-mineral supplement. The ants gobbled diverse insect prey and occasionally fresh frog or baby mouse carcasses. Though generalized predator-scavengers, they seemed to have a special fondness for termites.
I used forceps to pick out large uneaten prey items and a shop-vacuum to remove accumulated fine debris. Occasionally live ants were accidentally vacuumed. These were retrieved from the vacuum's reservoir and, though momentarily stunned and justifiably agitated, were usually unharmed by their turbulent joy ride.
No Pain, No Gain: The tanks were easily serviced if ant-alarming vibrations were avoided. Even so, we established a safety protocol. The aforementioned medical supplies were kept handy. The tanks were labeled "HOT" indicating dangerously venomous animals. Keepers always used long forceps and required spotters during risky maneuvers. No one was stung during routine servicing, although I took a few strikes when making disruptive manipulations.
One hazardous and now humiliating sting mishap, and a definitely to be avoided first-aid procedure are worth sharing. A knowledgeable and respected myrmecologist suggested that Paraponera venom may be heat labile, like some marine invertebrates, therefore deactivated by heat application. Shortly thereafter I received a bad hit on the finger and, willing to try this sage advice, immediately plunged my hand into the hottest tolerable water.
Not surprising in retrospect, this procedure swelled blood vessels, elevated heart rate, quickly flushed the venom into my system and caused a terrible reaction. The pain felt like an elephant was pirouetting on my arm. Soon becoming nauseous, I was forced to remain prone on the Insectarium floor for several hours. The Zoo's paramedic found that I was in mild shock and recommended visiting the local hospital emergency room. Perhaps foolishly and certainly bullheadedly, I opted to tough it out and later resumed work.
I am well aware of the possibility of developing venom hypersensitivity and the consequences of anaphylactic shock. I am also determined to avoid additional stings, but an occasional accident is inevitable with continued work. My current treatment protocol is to immediately employ an ice water bath to slow venom spread, and ingest a maximum dose of antihistamine tablets to counter allergic response. I recently tried this procedure in the field. It was reasonably effective in mitigating pain while, made sleepy by the antihistamine, I thankfully snoozed through the worst part of the reaction.
Social Collapse: The colony's wildcaught brood produced workers and winged forms, but later yielded only males. Since males develop from unfertilized eggs, all four original wingless queens were probably unmated. Consequently, the colony gradually declined; after 18 months there were about 30 wingless queens, 200 workers and a few winged ants. Curiously, wingless queens often functioned like workers, foraging for food and tending brood.
I used this group to test a newly completed observation nest intended for public exhibit. The nest, cast from hydrostone cement, depicted naturalistic earthen tunnels and brood chambers. Ants were introduced by anesthetizing them with carbon dioxide gas, then quickly transferring them to the fresh holding tank before they woke up. As ants resumed activity, I was encouraged to see them hauling their brood into the observation nest.
Two years post-collection, there were about 20 wingless queens, 50 workers, several males and little brood. Regardless, I was confident that bullet ants could be kept long-term and reproduced. I became anxious to replace this dwindling band with an actively growing colony. The ants were euthanized to ready the observation nest for another try and, if all went well, public exhibit.
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| Long Live The Queen!: I released Her Royal Majesty and 500+ entourage collected April 1995 into a new housing system containing the observation nest. This set-up, initially maintained in our rearing area, was designed for public viewing. We used two 60-gallon showtanks, desirable for their extra heavy plate glass walls and taller sides, fitted with decorative double-locked plywood caps. Each lid end has a two-inch diameter hole for an interconnecting ant runway. While off-exhibit, tanks were abutted thus connected by a short plastic tube. |
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When freed, the ants first explored then carted their remaining brood into the observation nest. As they settled into housekeeping, I soon saw foragers returning with prey, other workers carving up food and feeding larvae and, joyfully, the queen laying eggs! However, for several months the colony population plunged dramatically, probably because brood loss during collection, and the resulting gap in worker production, could not keep pace with worker mortality. I worried like a mother hen, but eventually the family stabilized then began to grow. |
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It is now July 1996 or 15 months post-collection. The colony, still queenright, has about 900 workers, several dozen males and lots of brood. New workers emerge daily and the nest is overflowing with ants. Several planned additions should, at least temporarily, relieve condo congestion. I finally have the vigorous bullet ant colony that I wanted, though it demands food and attention, and I am sometimes unsure who is keeping whom.
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