Representatives for Linn and the banks did not respond to requests for comment.The Granite Wash oil
patch is located in the Oklahoma and the Texas Panhandle and comprises liquid-rich sandstone.
Leanne Goacher, from the RSPCA, explained: "To wash oil
off the birds you use washing up liquid and hot water, but it's very specialised and people shouldn't try to do it at home.
If the spilled oil reaches shore, water hoses can wash oil
off beaches or sponge-like materials called "sorbents" can absorb the oil.