Spinal Deformities

Double-crested Cormorant, August 29, Kingston, Ontario
Juvenile found in small, artificial outdoor city pond; very weak and thin-1150g only, and had many lice (an indication of illness). Died immediately. The unfortunate cormorant had become tangled in fishing-line.

Body seemed stunted and the bird was thin. It had a severe lower-back spinal deformity, as if its egg had been brick-shaped. The Canadian Wildlife Service was interested in having the body as their studies had found unhatched chicks with similar spinal deformities, which they had ascertained were caused by ingesting PCBs in the fish the nestlings had been fed.

How did this badly deformed bird get from far out in Lake Ontario where their breeding colonies were, to the park pond about 8km inland? Presumably, the deformity did not prevent it from flying.

                                       

Great Blue Heron, juvenile, male, July 30
Severely emaciated fledgling, only 1280g. Bizarrely deformed body, causing staggering walk with legs bent and widely spread, so much that the tertiaries were raised upwards by each kneelift! Euthanasia immediately.

Post-mortem revealed healthy internals. X-rays showed scapulas curved, ribs wildly spread and spine twisted by unbelievable scoliosis.

 

 

 

 

 

 


Great Blue Heron, juvenile, October 11
Witness said the heron stumbled, legs apparently tangled, and fell down. We kept it just one day to observe. It could stand and walk apparently normally, but its rear view was lopsided and its wings tended to hang unnaturally, and the young heron made no attempt to fly. Euthanasia.

Post-mortem notes not found, but probably the heron was male; 1620g and thin, which would be a reasonable weight for a female. Healthy males we have recorded were from 2100g - 2500g or more. A burning question is, how did he live so long, when Great Blues fledge in late July to early August?


Return to Main

Last updated: February 28, 2005

Web page developed and maintained by Sutton Software Systems

bsutton@kos.net