"Every time I leave the building I keep waving my hands over my head," said Mario Roxo, a 75-year-old chauffeur who had his head badly scratched by a hawk.

The O Globo newspaper reported that one woman lost part of her scalp to a hawk and another man mistook an attack for a stray bullet.

Rodgrigo Carvalho, a biologist with Brazil's environmental agency, said the hawks were just trying to defend their young.

"This happens all the time in poor areas and people think it's funny, but when it happens in a rich neighborhoods they start calling them attacks," Carvalho said.

He estimates as many as 1,000 hawks live in the city, flourishing because of a lack of predators and easy access to rats, pigeons and garbage.

Residents have asked the fire department to remove the nest, but officials say they cannot until they get approval from Brazil's environmental protection agency.

They urged more protection for seas around the Bird's Head peninsula at the western end of New Guinea island from threats including mining and dynamite fishing that can smash coral reefs.

"We feel very confident that this is the epicentre of marine biodiversity" in the world, said Mark Erdmann, a U.S. scientist at Conservation International who led two surveys this year.

The scientists found 24 new species of fish, including two types of epaulette shark, slim and spotty growing up to about 1.2 metres long. Among other finds were 20 new species of coral and eight previously unknown types of shrimp.

"It's especially stunning to find sharks - these are higher level creatures, not bacteria or worms," Erdmann told Reuters. The sharks get their name from markings on their sides like epaulettes - decorations on the shoulders of military uniforms.

The researchers also found new species of "flasher" wrasse fish. The males, which keep harems of several females, suddenly "flash" bright yellows, blues, pinks or other colours on their bodies, apparently as part of a sex ritual.

Erdmann said the region, covering about 18,000 square kilometres, had a greater concentration of species than Australia's Great Barrier Reef.

He said Indonesia's Fisheries Ministry wanted to increase the number of marine protected areas, currently covering only 11 per cent of the area around the peninsula.

"We are very concerned about the potential impact of planned commercial fisheries expansion in the region," said Paulus Boli, a State University of Papua researcher.