It comes amid record-breaking temperatures in the UK, which also killed more than 50 fish in the lake at Brooklands Park.
However, the council said the heat is not necessarily the cause of the birds’ deaths.
A Worthing Borough Council spokesperson said: “A small number of dead birds have been found at Brooklands Park unfortunately.
"It is not yet clear exactly what has caused the deaths but as a precaution we have notified The Government’s Department for Environment, Food and Rural Affairs Defra in case it involves avian influenza.
“If avian influenza is the cause, the risk to the health of the general public is very low. But as a precaution it is important you do not touch or pick up any dead or visibly sick birds you find.
“If you find any dead wild birds in any location, including swans, ducks, geese, gulls, or birds of prey, please report to Defra as soon as possible.
Worthing Borough Council is working with Defra in the clean up.
“Anyone who spots any dead birds should call the Defra Hotline on 03459 33 55 77.”
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