Dangerous Bird #2

The Masked Lapwing can be very aggressive when defending its nest. Its old name was Spur-winged Plover. The photo shows the spurs, which the bird is quite prepared to use on humans who get close to its nest. The nest, shown in the photo, is a simple circle of decaying grass clippings left over from the last time this nearby lawn was mowed. I would have liked to get closer to the nest, but I retreated when confronted by the bird's, and its partner's, aggressive behaviour. Professional photographer Graeme Chapman was braver than me and posted these images of a nest and chicks (scroll to page 2 of the view). 

I previously blipped the Masked Lapwing last January. The spurs were not visible then. I wonder it they develop during the breeding season?