Topical Issue on Fish Ecology
Open Access

Table 2

Number, exposure, and occurrence of mortality and injuries in yellow– and silver-phase American eel exposed to rapid decompression simulating hydroturbine passage. Percentages represent the portion of exposed fish that were recorded with the designated injury or observation.

Yellow-phase Silver-phase
Exposure
   Nadir (kPa) median (range) 2.4 (1.2–8.1) 2.7 (1.6–8.4)
   RPC median (range) 10.2 (3.1–21.4) 9.3 (3.0–16.1)
n 105 108
   Control 4 18
   Exposed 101 90
Instantaneous mortality 0 0
Injured 11 (10.9%) 12 (13.3%)
   Swim bladder rupture 6 (5.9%) 0
   Emboli  
     Heart 0 1 (1.1%)
   Hemorrhaging    
     Intestinal 1 (1.0%) 0
     Liver 0 4 (4.4%)
     Heart 0 1 (1.1%)
     Swim bladder 3 (3.0%) 1 (1.1%)
     Pectoral fin 3 (3.0%) 1 (1.1%)
     Anal fin 0 3 (3.3%)
     Dorsal fin 0 1 (1.1%)
   Hematoma
     Liver 1 (1.0%) 1 (1.1%)
   Ruptured gall bladder 0 5 (5.6%)
   Intestinal volvulus 1 (1.0%) 0
   Burst capillaries along kidney wall 1 (1.0%) 0
Parasites 52 (49.5%)* 98 (90.7%)*
Expelled gas during decompression 45 (45.0%) 64 (71.1%)
*

Percentages include controls.