Positive signs on the Cairns mudflats
It may be stretching the point to suggest the Cairns Esplanade is back to full health after several years of sand-spreading by the city’s regional council. But there are positive signs.
As Natural Images has reported over several years, once world-class wader viewing along the city’s Trinity Bay inter-tidal mudflats was all-but lost.
Where thousands of shorebirds once gathered to feed and roost between tides, in the space of five years, the numbers had dwindled to a couple of hundred – at best.
The major culprit was a misguided beach creation campaign by the Cairns Regional Council (CRC). Massive quantities of sand (much of it trucked in) were spread all along the shoreline, only to be washed out over the mudflats by successive tides and storms.
The sand quickly smothered the previously organism-rich mud, forcing the wading birds to look elsewhere for food. Formerly safe roosting sites were also compromised because humans and their animals could suddenly walk out into the bay across a crust of sand.
But persistent lobbying by a small group of local birders seems to be delivering positive results. The CRC has stopped spreading sand along the southern half of the bay, removed significant quantities from trouble spots and committed to build a series of groynes to contain further sand creep.
With that, and unexpectedly heavy siltation following major rain, a good layer of mud now covers the sand in many areas. There is evidence of more benthic life, and the crabs are back in big numbers. So, too, are the migratory waders.
On one morning in late October, I counted well over 1000 sharp-tailed sandpipers and red-necked stints feeding. And the following day, there was great excitement – an Asian dowitcher (a rare visitor to Cairns) was happily feeding and roosting among the godwits on the Esplanade.
It is also noticeable that the waders are sticking around longer than in recent years – undoubtedly because more mud means more food.
Unfortunately, because the council refuses to stop adding sand to the northern shoreline, come the next wet season that sand will likely be washed out into the bay and we will be back to square one.
©Natural Images 2019