She's lucky, too, that there is no sudden torrent of water in the creek. A heavy storm could dislodge the stream bed rock and crush her. Upstream from Onco's redd, riffles mix air with water to give the eggs a rich oxygen supply. Without oxygen, the eggs would die. Ducks and other birds hunt for salmon eggs.
Raccoons find the same reward in shallow gravel.
Adult trout, too, love salmon eggs if the trout can get to them. But they do not find Onco in the gravel-covered redd. Aside from these natural hazards, the developing salmon egg has to survive some unnatural hazards. In another creek like Onco's, a mining dredge once ripped up the stream bed. Now, each year the loose soil releases silt which spreads far downstream.