The American Bittern
The American bittern, a widely distributed wading bird in North America is undergoing a nation wide decline. The greatest declines, (48% in over 20 years) occurred in the Midwest and north central states. Ignorance of this birds' life history serves to enhance its decline. The American bittern's position in the food chain place it at several trophic levels where it is exposed to pollutants and contaminants. The unusual pumping call during the breeding season may make it one of the easiest of the secretive marsh and wading birds to census. All of these factors make this bird an ideal bio-indicator of the health of inland and coastal wetland/grassland habitats. |
 |
The cage is wire with a mirror in the back of it. The cage is placed in the marsh with a tape recorder on the top playing the bittern mating call. When a bittern hears the mating call it investigates, and upon seeing itself in the mirror in the cage walks into the cage to investigate. Upon entering, the cage door closes and the bittern is trapped and unharmed. |
 |
This picture shows the wire capture cage and next to it, the cage the bittern is transported in back to the processing site. The transport cage is almost entirely enclosed in order to keep the bittern more calm. |
 |
Gary Huschle - Agassiz National Wildlife Refuge Biologist - is shown removing a bittern that has been trapped in the marsh cage. |
 |
Gary Huschle is placing the captured bittern into the transport cage - students observe the process. |
 |
Gary Huschle is removing the bittern from the transport cage back at the processing site. Care must be taken not to get your face close to the beak as the bittern will try to peck at your face and eyes. |
 |
The bittern has a very long neck with a long beak, and it also has long legs. When it has its neck stretched out and is standing, the bird is approximately 2.5 ft. tall. |
 |
A mask or hood is placed over the bittern to help keep it calm for processing. |
 |
The length of the beak is measured and recorded |
 |
The wing length is measured and recorded as well as a feather sample take for lab analysis. |
 |
The bittern has long talons. |
 |
Students help in the processing - here a student is recording data for the biologist. |
 |
Students help to sort and count bird bands - even though the bittern will have a radio collar on it, a leg band is also placed on each processed bird for further identification. |
 |
As technology improves, collars are made smaller and more lightweight in order to be as non-interfering to the animal as possible |
 |
If the collar to bittern weight ratio is too large, the collar cannot be used on that bird |
 |
The radio collar is slipped over the bittern's head and will ride around the neck. The local movements on the refuge will be tracked using radio telemetry equipment. Later in the summer, prior to migration, the bird will be located, recaptured, and a satellite collar will replace the radio collar. |
 |
This marsh habitat is preferred by the bittern |