Tern watches have spotted them in the estuary and marina.
Fairy Tern make up the 50 species of rare bird thought to be in the Mandurah area.
No terns have been spotted yet at the special Mandurah Fairy Tern Sanctuary at Mandurah Quays.
Mandurah CEO Mark Newman said the public are asked to keep their distance from the sanctuary fence and breakwater wall behind the site.
“Disturbance early in the season will deter them from nesting; but once they’ve settled, they’re a bit more resilient,” he said.
“If you are walking your dog in the vicinity make sure it is on the lead, and any pet cats in the area must be contained."
The Sanctuary was established by the City of Mandurah and multiple project partners to provide a safe nesting space nearby the 2016-2017 nesting site on a then-vacant development Lot.
A number of Fairy Terns flew repeatedly over the Sanctuary last year after it was completed, which authorities said was a good sign and confirmed ecological advice that it could take up to three seasons for a colony to successfully nest within the site.
Anyone interested in being involved in the conservation of this Threatened Species or assist in the important university research on Fairy Terns commencing next month, can do so by contacting the City’s Environmental Services.
Long-term Pinjarra resident gifts Shire heritage railway carriages, brake vans
Extent of damage to Bar Therapy following devastating fire revealed
MARC pool reopening date announced after three year closure
Yunderup Island blaze under control
Mandurah's Bar Therapy damaged by fire
Postman injured in Wannanup crash
Man charged after allegedly stealing service medals from Greenfields storage unit
South West resort receptionist charged with 32 fraud offences
Daughter of Port Kennedy hit-and-run victim pleads for offenders to hand themselves in