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Non-Native Species
Lehmann lovegrass and other non-native grasses
are the most important non-native species issue at
the park. The change in species composition in the
semi-desert grassland to a community dominated
by Lehmann lovegrass, in particular, can alter the
fire regime of the area by supporting higher fire
frequencies, thereby leading to other changes in
vegetation composition and structure including a
loss of species richness (Anable et al. 1992).
The presence of American bullfrogs is
another important non-native species management
issue. Bullfrogs are native to eastern North
America but have been introduced throughout the
western U.S. for food production and sport
(Stebbins 2003). American bullfrog adults and
tadpoles are voracious predators (Kiesecker and
Blaustein 1997) and are thought to be partially
responsible for the decline of many native reptiles
(Schwalbe and Rosen 1988) and amphibians
(particularly other Ranid frogs; Hayes and Jennings
1986, Lawler et al. 1999) in the southwest.
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Undocumented Immigrants
Approximately 20 undocumented immigrants pass
through the park each week (NPS 2003). In
addition to compromising visitor safety, border
crossers also adversely impact the natural
resources; they have created trails (including into
the fort ruins), damaged vegetation, and have left
trash behind. These impacts affect water quality
and wildlife movement patterns, though the extent
of these impacts has not been established.
Adjacent Land Use
Due to its small size, the park is easily affected by
land management practices (e.g., development,
mining, grazing, and hunting) outside its
boundaries. Currently there is a Buddhist retreat
center being built to the north of the park, but
because the remainder of the land surrounding the
park is managed by the BLM, ex-urban housing
development is unlikely to significantly affect the
park’s resources.