by Ian Brown, Brisbane
All finches require some sort of natural material to construct or line their nests. Back to Basics Chapter 8 describes the types of nest boxes, cane baskets and brush more commonly used by finches. In this chapter we will discuss the various types of material finches require to build or line nests with.
Most nests constructed in brush require an outer layer of long, coarse grasses or fibres that can be woven and shaped to suit the individual species preferred design. Whether it be a cup shape or dome with spout this initial construction has to be rigid. Most Australian finches build a rather large nest and can use grass up to 400mm long. African finches tend to use a little softer grasses and not quite as long as the Australians.
Some common grasses used for this outer layer include:
Kangaroo grass (themeda triandra )
Wire grass (aristida ramose )
Spear grasses (austostipa spp. )
Wallaby grasses ( austrodanthonia spp. )
These are clumping grasses and can be cut close to the ground leaving you with various lengths and thicknesses to give variety to the birds. Another long common grass used is Couch. The runners can be pulled up in long pieces and placed in the aviary allowing the birds to sort through finding the preferred pieces to suit their needs. If given the choice most birds will use green grasses to build with as they can shape it easily as dry grass tends to break.
Panic grasses (panicum virgatum spp.) are also used. Weavers in particular use green panic strands to weave their elaborate nests. The cock bird will snip the edge of a leaf and fly away, tearing a thin strand off and carrying it to the nest site. It is best to have panic grasses growing in the aviary when keeping weavers. However, cut panic grass will be used by most birds if supplied, particularly the seeding head shafts that are fairly strong, allowing a solid structure to be formed.
Once the outside layers have been formed to the desired shape and size the nest is then lined with softer material. These can include November or Swamp grass (lachnagrostis filiformis syn.Agrostis avenacea ) which are the more common varieties found, and also coconut fibre, paper bark and feathers, generally white in colour.
Birds that use a ready made structure in which to nest, e.g. hollow logs, boxes, wire and cane baskets etc., tend to only require softer material to line the nest site. November grass is the preferred material. This grass can be harvested around the month of November in Australia, hence the name, the seed head is the part of the grass that is used by most birds as it is soft but quite sturdy. It can be found in low lying, damp areas. It is quite often found blown up against fences after the seed has been shed and the stalks dry enough to be blown away from the plant itself.
Birds that build cup nests can use a variety of materials. They will use both coarse and soft grasses, coconut fibre, spider webs, bark, lichens, leaves and feathers.
Another widely used material is cotton wool. It should be the natural type and not the synthetic type as the birds will find it impossible to escape from if they get caught in it. The natural one can be hung in an onion bag and the birds can pull out small amounts to line their nests.
Other materials used in the past have been shredded hessian bags (potato sacks) and Kapock (cotton stuffing used in old mattresses), horse hair and Emu feathers. Some of these items are becoming hard to find as they have been replaced by synthetic materials, much to the frustration of bird keepers. As mentioned earlier, synthetic materials are very hard for birds to escape from if they get caught by leg rings, or fine strands around the birds legs or wings and if these materials are used in the lining of the nest you might not know if your bird is caught resulting in the loss of the bird. Most natural material is weaker and can be escaped from by chewing by the birds if they do get caught.
It should be mentioned that if nesting grasses are to be stored that they need to be completely dry so that they do not develop mould or mildew. Either put them in a box out in the sun for a couple of days till they have dried out completely or hang bags of grass in a well ventilated area to dry out before storing them.
In conclusion it is recommended that only natural nesting material is used and the best of them all would be the good old reliable November Grass.