Hi Fani, yes the sacks are to protect the edges from water erosion. They were placed around most of the island in Sept this year. There would not really be erosion if the water level remained fairly constant, but it fluctuates quite a bit and rose far too much this past winter. 

Lovely pics everyone!! They are such beautiful birds, one can't get tired of looking at them.

Zoomed in on the sky at sunset because it was most beautiful when viewed from my garden, but the webcam can't do it justice.  A huge storm blew past - it would have been great if it had rained on the flamingo island and made some wet clay for more nest building on the drier sections. 

Pink in the sky

The sun is gone

Touched by the late afternoon sun

One would forget they are there to breed.

Wow! ...again