Examples of safe and unsafe substrates and nesting materials

The choice of substrate and nesting material has a huge impact on the health and welfare of captive hedgehogs and tenrecs. A good substrate supports natural behaviours like digging, burrowing, and nest building, while a poor choice can lead to respiratory problems, injuries, or stress. Because these animals are small and sensitive, even seemingly minor materials can have serious consequences.

Safe and Commonly Used Options

Fleece liners
Many keepers use fleece liners because they are washable, reusable, and reduce dust. They are safe for sensitive feet and do not cause respiratory irritation. However, fleece provides little enrichment. It is a flat, uniform surface that does not allow digging or natural foraging behaviour. For this reason, fleece works best in combination with other enrichment such as digging boxes, scatter feeding, or nesting materials, rather than as the only substrate.

Paper-based bedding
Shredded paper or compressed paper pellets are safe, dust-free, and absorbent. They allow some digging behaviour and are often recommended in rehabilitation or rescue settings. Paper bedding needs frequent replacement because it saturates quickly, but it is one of the safest choices for young or sensitive animals.

Coconut fibre, soil, and play sand
These natural substrates mimic outdoor conditions and provide excellent opportunities for digging and foraging. Washed play sand, sterilised coconut fibre, or organic soil can be used safely if sterilised beforehand (by baking or microwaving). However, they require more maintenance, as they can harbour bacteria or mould if not cleaned regularly.

ay and dried leaves
Hay and leaf litter can be used as nesting material, giving animals the chance to build natural shelters. These must be clean, pesticide-free, and replaced frequently to prevent mould growth.

More Advanced Option: Bioactive Substrates

Bioactive setups, where substrate is combined with live plants, microfauna (like springtails and isopods), and natural decomposition, are increasingly popular. They create a self-cleaning ecosystem and can mimic wild conditions. However, bioactive systems require significant experience.

• They need careful balancing of temperature, humidity, and light to prevent harmful bacteria or mould.
• Not all clean-up crews are safe for insectivores; some may be eaten in excess, others may stress the animal.
• Monitoring is essential, as an imbalance can cause rapid decline in hygiene.

For this reason, bioactive substrates are best reserved for experienced keepers who can commit to the maintenance and observation required. For beginners, simpler substrates are safer and more reliable.

Unsafe or Questionable Materials

Sawdust and wood shavings
Not all types of sawdust or wood shavings are safe. Cedar and pine, especially when fresh, contain aromatic oils (phenols) that can irritate the respiratory system and damage the liver over time. Fine sawdust is also dusty and can cause eye, nose, and lung irritation. If wood shavings are used, only kiln-dried, dust-extracted hardwood or aspen shavings are suitable.

Cat litter
Clay-based cat litter is dangerous because it clumps and can cause blockages if ingested. The dust can also irritate lungs and eyes.

Straw
Straw is coarse and can cause eye injuries or puncture wounds. It does not make good nesting material for hedgehogs or tenrecs.

Synthetic fluff or cotton wool
Marketed as nesting material for small pets, but extremely unsafe. If ingested, it can cause intestinal blockages; if wrapped around legs or toes, it can cut off circulation.

Nesting Material Essentials

• Regardless of substrate choice, all hedgehogs and tenrecs need safe nesting materials to build shelters.
• Paper strips, hay, dried leaves, and untreated grasses are ideal.
• Always avoid fibrous or clumping materials that can tangle, block digestion, or harbour moisture.
• Change nesting material regularly to keep it clean and dry.

In Summary

• Fleece is safe and easy to clean but offers little enrichment on its own.
• Natural substrates like paper, coconut fibre, soil, and sand provide digging opportunities but need frequent cleaning.
• Bioactive substrates can be highly enriching but require advanced care and constant monitoring.
• Unsafe materials like cedar, pine, straw, and synthetic fluff must be avoided due to health risks.

The best substrate is one that balances safety, hygiene, and behavioural enrichment, giving hedgehogs and tenrecs the opportunity to live healthier, more natural lives in captivity.