Iliamna Lake island beaches are typified by large gravel,
with large interstitial spaces and few fines (e.g., Leonetti
1997). This high porosity allows wind-generated under-gravel
water flow to supply the developing embryos with oxygen, but
may also account for the presence of coastrange (Cottus aleuticus)
and slimy sculpin (Cottus cognatus) that have been observed
feeding on salmon eggs (Kerns and Donaldson 1968).
The greater the substrate size, the greater the ease with which
sculpins can move within it, and the more vulnerable salmon
eggs are to predation (Phillips and Claire 1966). These sculpins