''The harrier hawks have had quite an impact. Without them we could have had eggs hatched earlier. Once dotterels can look after themselves, their survival is not as critical.''
Another factor is Whangamata's population growth and more visitors to the area while New Zealanders aren't travelling overseas.
''And more people around means more cats and dogs too,'' he says.
It's a more positive outcome for the overall region — Department of Conservation (DoC) Northern region is expecting a positive productivity rate for the dotterel as breeding season comes to a close in the Coromandel.
Their area includes the Coromandel Peninsula from Whiritoa north and all beaches north of Thames.
Ranger Frouk Miller expects about 140 chicks to fledge during this breeding season which began in late August until mid-March for the region.
A noticeable change this season has been the surge in visitors to the Coromandel because of Covid-19, she says.
Frouk says the increase in visitors has brought with it the higher risk of "dog versus dotterel" incidents – with chicks becoming targets for dogs.
"They can't fly for at least six weeks and they need to forage for food themselves from day one," she says.
"People are always amazed when told the adults don't feed their chicks like other birds. They're purely there to guard and teach them and keep them safe."
— Additional reporting Department of Conservation