Polyrhachis dives Care Sheet (Weaver Ant)

This long-form care sheet focuses on stable, repeatable husbandry: a usable temperature gradient, a moisture gradient the ants can control, and a feeding schedule that matches natural behavior. Always prioritize observation: brood placement, foraging intensity, and how quickly food is processed are better signals than any single number.

Quick profile

• Difficulty: Intermediate
• Origin: Southeast Asia, Northern Australia
• Temperature: 25–30°C (77–86°F)
• Humidity: 60–80%

Natural range & habitat

Polyrhachis dives is a fascinating species of 'weaver ant' found across the tropical and subtropical regions of Asia and Oceania. Unlike the better-known Oecophylla weaver ants, Polyrhachis dives often nests closer to the ground, using larval silk to weave together leaves, soil, and debris into intricate, paper-like nests. They are highly successful and often polydomous (having multiple nests) and polygyne (having multiple queens). Their bodies are covered in a dense, silvery pubescence and they possess formidable spines on their thorax and petiole, which serve as a defense against predators.

In captivity, recreate the pattern of the habitat: offer warm/cool choices and wet/dry choices. Many colonies relocate brood through the season or even within a week, selecting microclimates that optimize larval growth and pupation.

Nest setup

Start in a space the colony can control. Over-sized nests dry out unevenly and encourage trash buildup inside chambers. A good progression is a test-tube (or compact starter nest) into a small formicarium, then modular expansion as worker numbers demand it.

• Founding phase: Keep it dark, quiet, and stable. Disturbance is a common reason queens eat eggs or pause laying.
• Expansion triggers: Workers sleeping in the outworld, brood pressed against viewing windows, or persistent traffic jams at entrances.
• Outworld basics: A clean container, a feeding dish, a water source, and a reliable escape barrier outperform complex decor.

Temperature management

This is a truly tropical species that requires consistent warmth to thrive. Maintain the nest and outworld between 25°C and 30°C. They are most active and show the best brood growth at the higher end of this range (around 28°C). Use a heat mat or cable with a thermostat to ensure temperatures do not fluctuate too wildly. Cold drafts can be lethal to the colony, so ensure the setup is in a stable environment.

Apply heat to one side only. Optional warmth lets the colony self-regulate and prevents chronic overheating. If workers constantly evacuate the nest to cooler areas, reduce heat or improve the gradient.

Humidity & hydration

High humidity is essential for both the ants and their unique nests. Aim for 60-80% humidity. If the environment becomes too dry, the silk nests can become brittle and the brood may fail to develop properly. Regular misting of the outworld and providing a large, open water source help maintain these levels. However, ensure there is good ventilation to prevent the growth of harmful fungi or stagnant air conditions.

Humidity should be controlled, not flooded. Provide a moist brood zone and a drier retreat. Over-watering increases mold and stress; under-watering slows brood and can cause workers to linger at the water source.

Feeding

Polyrhachis dives are active and opportunistic foragers. They require a constant supply of carbohydrates to fuel their busy lifestyles—sugar water or honey water should be available at all times. Protein is equally important, especially for the larvae that provide the silk for nest building. Offer a variety of insects 3-5 times a week. They are moderately aggressive and will work together to bring down larger prey items.

• Carbohydrates: Sugar water, honey water, or nectar 2–4 times per week (more often for highly active species). Replace before fermentation.
• Protein: Feeder insects are ideal. Offer small amounts frequently and remove leftovers within 24 hours.
• Water: Always available. Hydration problems often look like “random” brood stagnation.

Outworld, substrate & enrichment

Use enrichment that does not trap waste: cork bark, a few stones, and removable dishes. A thin substrate layer is optional. Ants show more natural foraging when they can move around obstacles and drag prey into cover.

Brood development & growth expectations

Brood development is relatively fast in the heat. The larvae are particularly interesting because they are the 'tools' used by the workers to build and repair the nest. When the colony needs to expand, workers will carry larvae to the construction site and tap them with their antennae to induce silk production. Eggs to workers takes about 6-8 weeks. Because they are often polygyne, colony growth can become exponential very quickly.

Track progress weekly. A healthy colony typically shows: steady eggs during the active season, larvae increasing in size after feedings, and pupae eclosing on a predictable cadence. If growth stalls, check (1) temperature is warm enough, (2) protein is frequent enough, and (3) brood has access to the correct humidity zone.

Hibernation / diapause

Polyrhachis dives comes from regions without a cold winter, and therefore they do not require any form of hibernation or diapause. They will remain active and continue to produce brood year-round as long as the temperature and humidity remain stable. If activity slows down, check that the temperature hasn't dropped or that the colony isn't becoming root-bound in their current nest space.

Common issues

• Mold: Feed smaller portions, remove leftovers quickly, and avoid soaking the nest. Mold is usually a symptom of excess moisture plus food residues.
• Escapes: Refresh barrier weekly and keep lids/ports tight. Activity spikes after feeding are when most escapes happen.
• Brood loss: Often linked to overheating, dehydration, or constant disturbance. Re-stabilize and keep the nest dark for a week.

Keeper tip

Let the ants choose: if you provide both warm/cool and wet/dry options, brood placement becomes your best diagnostic tool. Brood hugging the warm side usually means temperature is limiting; brood piled near hydration points suggests the nest is too dry.