Zinc & Birds
We are occasionally asked about the effects of the zinc coating used on all sorts of steel products including welded wire mesh and their effects on birds and animals. There are various ways in which zinc (galvanising) is applied to steel products to prevent rusting. The most common and most effective form of galvanising is by the "hot dip" process, which immerses the steel product in molten zinc - this deposits a thick coating of zinc and is far more effective than electro-galvanising which always produces a thinner and brighter coating. The thicker the zinc coating, the longer the product will last in any environment compared to electro galvanising (also called electro plating).
Excessive zinc ingestion or consumption is not good for any animal, bird or human for that matter. So here are a few tips on how to manage your galvanised product where you want to. The following is in the context of keeping birds within an enclosure using a galvanised mesh product.
Galvanized Wire - Galvanized metal which has been electroplated is safe (because it a a very thin coating and attaches differently to the host steel material), but galvanized wire (hot dipped) is not. Birds can ingest zinc from cages and clips made of galvanized wire. Toxicity can be reduced (but NOT eliminated) by scrubbing the wire with a brush (not a wire brush as this will remove the zinc coating and allow the steel below to start rusting) and vinegar or a mild acidic solution. This removes any loose pieces and the white rust (zinc oxide) which forms on the wire. Over time more white rust which is also poisonous will form, so enclosures must be re-treated periodically.
Remember, that each bird is different. Some chew on their cages more than others and are thus more likely to ingest white rust. Bigger birds with more powerful beaks can break off pieces more easily than small birds. Most birds don't eat non-food items, but there are some who will. If you have birds in a large aviary with lots of branches or items to occupy them, they are much less likely to chew on the cage wire.
Prevention - can I do it? Zinc poisoning is from your aviary wire. Batches of wire can vary in their toxicity level.
Aging the wire is usually recommended, if you have the time available you can leave the roll out in the weather for at least 12 months before using it. Washing the wire in an acidic solution (10 % vinegar solution) is also recommended but is not 100% effective. Purchasing a wire with a plastic coating will most likely work if the bird species is not a great chewer.