field Studies

Every year hundreds of field hours are spent conducting call counts. Clapper rails are so secretive, the best way to count them is by listening for their calls. Nest surveys are conducted to determine breeding potential. Sometimes eggs are collected as a source for new rails for the zoological breeding stock.


The zoological breeding team (SeaWorld, San Diego Zoo Safari Park, and Living Coast Discovery Center) maintain between six to ten pairs of rails for breeding. Living Coast Discovery Center has the distinction of being the only facility to have an open display of the Light-footed clapper rails.

pre release

Each Light-footed clapper rail bred for release into the wild spends four to eight weeks in a transition enclosure. This is a critical time when the birds learn to forage and are evaluated for release. The enclosures are located on Sweetwater Marsh and managed by Wild Wings Research.

Post Release

Each rail is fitted with an identification band prior to release. However, band sightings are rare once the birds are released. Some small studies with radio telemetry have been conducted and given some insight to post release movements. More studies are needed.

The Light-footed clapper rail, Rallus longirosris levipes, is one of the most endangered coastal birds in southern California. Habitat destruction and fragmentation of coastal wetlands resulted in the near demise of this secretive marsh bird. In the 1980s, populations of the this bird reached a critical low of fewer than 200 pairs between 23 sub-populations. The decline of the clapper rail was attributed to a genetic bottleneck as a result of wetland fragmentation and destruction.

In 1998, a partnership between SeaWorld San Diego, United States Fish & Wildlife Service, Chula Vista Nature Center, San Diego Zoo, California Department of Fish and Wildlife, Richard Zembal (Principle Investigator), and several NGOs was created to increase the population and improve the genetic composition of Light-footed clapper rails through  captive breeding and release activities. Since 2001, more than 400 rails have been bred and released into the wild. Between release efforts, habitat improvements, and educational programs,  the wild population has more than doubled.





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Light-footed Clapper Rail:

Help us restore California's rarest Waterbird - The LIGHT-FOOTED CLAPPER RAIL

Team Clapper Rail

Restoring an Endangered Species