Chapters 1 - U.S. Fish and Wildlife Service

Chapter 3
species habitat; the season during which the predator is present; and the level of vulnerability
of endangered species to the particular predator species. Based on the specific criteria
associated with these factors, various actions are taken to assure that endangered species
protection and population objectives are achieved while avoiding excessive removal of
predatory animals.
The control of mammalian and avian species with the potential to harm the Refuge’s listed
species is currently conducted by the Refuge Manager. In the past, this activity has been
implemented by an outside contractor who maintains regular contact with the Refuge
Manager. At the end of each breeding season, a predator management report describing the
monitoring and control methods implemented during the past year is prepared and kept on file
in the Refuge Headquarters. Control methods can range from harassing potential avian
predators to keep them away from nesting areas to rare instances in which lethal control of
known problem individuals is the only remaining option. To reduce the need for lethal control,
a number of actions are taken to reduce the potential for predation. These actions include the
installation of an electrified fence around NASA Island, placement of terra cotta tiles in the
nesting area to provide some protection for chicks from avian predators, hazing of avian
predators at the tern nesting colony, and placement and continual maintenance of nesting
platforms in the marsh to provide safe refuge for light-footed clapper rails year-round, and
particularly during the nesting season.
Predator management generally starts one month before anticipated nesting, which is about
March 1 for the California least tern, and continues until all nests are fledged. Predator
management surveys are conducted regularly during the nesting season and consist of routine
walks around the Refuge noting tern activity, looking for evidence of potential mammalian or
avian predator activity in proximity to listed species habitats (e.g., actual sightings, tracks,
scat, holes or digging), inspecting the integrity of the electric fencing around NASA Island,
looking for signs of any illegal public access, and checking any traps for content. Endangered
species monitoring also assists the Refuge Manager in identifying potential predator problems
before they elevate to the point that lethal take would be necessary. Night mammal surveys
are conducted monthly on the Refuge and portions of the NWSSB. From these counts, the
Refuge Manager can obtain information about the range of potential predators present in the
immediate area and develop a general understanding of the number of each potential predator
species that may present.
Predator control methods for predatory mammals on the Refuge include live trapping and
shooting of feral cats, opossums, striped skunks, coyotes, and red fox. Manual live capture
methods such as box-type mammal traps, handheld capture poles, padded leg-hold traps, or
other manual techniques may be employed. All traps are inspected in accordance with State
Fish and Game Code and Service policy. When suitable relocation sites or facilities are
available, captured animals are transported and released to those locations. In the absence of
suitable relocation sites, captured predatory animals are euthanized at the trap site. Trapped
animals that do not pose a threat to listed species because of the time of year, the total
estimated number of that species on the NWS, or other factors are released at the trap site or,
if appropriate for the long term protection of listed species, to an area on the NWS that is well
away from the marsh. Problem avian predators are generally live-captured and released at an
appropriate distant off-site location. Lethal removal of predatory birds occurs in rare cases
when a problem predator cannot be trapped, there is an imminent threat to endangered
species, or it returns after release away from the Refuge and continues to prey on endangered
species. The techniques for avian predator control are implemented in accordance with agency
policies for safety and humane treatment of animals.
3-18 Seal Beach National Wildlife Refuge