| Some others, like the Siamese fighting fish, are capable of breathing air in addition to extracting oxygen from the water with their gills. |
| To make matters worse, fish have large respiratory membranes, the gills, which expose a huge amount of surface area to the watery medium. |
| At fish-cleaning stations, cleaner fish nibble the parasites from the gills and mouths of fishes much larger than they are. |
| White-tailed eagles, which inhabit the same territory, may struggle for hours merely to pry an opening around a fish's gills or front fin. |
| Otherwise they have to keep swimming to force oxygenated water past their gills. |
| It takes several weeks after hatching to form and until then they are dependent on water absorbed through the gills, the same as any other fish. |
