endemic bromeliad species. The family's distribution
and ecology in Costa Rica has been presented in Burt-
Utley and Utley (1977),
Most bromeliads can be recognized by their ro-
sette of water-impounding leaves, which are covered
with scales, and by their conspicuous inflorescence,
which often has colorful bracts. Bromeliads are usu-
ally notable elements of wet neotropical forests,
where they are often the most numerous and mas-
sive epiphytes present. They are an important source
of shelter and food for a variety of animals (Nadkarni
and Matelson 1989, Benzing 1990) and play an im-
portant role in forest nutrient cycling (Nadkarni
1986, Benzing 1990).
A total of 72 species have been found in the Monte-
verde Reserve Complex and immediately outside the
MCFP in dry and warmer habitats. Monteverde spe-
cies belong to the subfamilies Brornelioideae (leaves
mostly serrate-margined, ovary inferior, fruit a fleshy
berry, seeds unappendaged), Pitcaimioideae (leaves
mostly serrate-margined, ovary mostly superior, fruit
a dry capsule, seeds caudate or winged), and Tilland-
sioideae (leaves always entire, ovary superior, fruit
a dry capsule, seeds plumose; Appendix 4).ORCHIDS
John T+ Atwoodproject on the Orchidaceae of Monteverde
was initiated in 1988. With preliminary esti-
mates ranging from 300 to 350 species (At-
wood 1987), the list tallies more than 500, the highest
orchid species diversity known from any comparable
area of the neotropics (C. H. Dodson, pers. comm.).
The orchids of Monteverde represent 39% of the or-
chids of Costa Rica, with an estimated 1270 species
(Dressier 1981). Monteverde's high species diversity
is probably due to a variety of life zones providing
diverse habitats (Tosi 1969), the high species richness
of midelevation tropical sites (Dressier 1981), the diver-
sity of pollinators, and high local collection intensity.
Most orchids of undisturbed forests exhibit narrow
elevational distributions. Maxillaria fulgens, found
from 1600 m to La Selva Biological Station (ca. 50-
100 m) is an exception. In Monteverde, the few or-
chids characteristic of the upper montane regions to
the south include species of Masdevallia and two rare
unidentified species of Telipogon (G. Barboza, pers.
comm.). Anomalous elevational range extensions
from lower sites may be due in part to pastures next
to forest fragments, and to locally warmer microcli-
mates. Pastures at 1550 m support Maxillaria cam-
panulata, M. nasuta, and Masdevallia nidifica, also
found below 900 m on the Atlantic slope. Encyclia
abbreviata and Nidema boothii, occurring at 1350 m
in Monteverde, are also known at La Selva.
Orchids are traditionally viewed as rare plants, and
pastures seem an unlikely place for their survival. Yet
species counts in two Monteverde pastures exceeded
- Elevated orchid diversity in fragmented habitats
has been documented elsewhere (Williarns-Linera
et al. 1995), so pastures may be significant for orchid
conservation. Threats to orchids include environmen-
tal degradation and exploitation of habitat-specific
orchids. Examples in Monteverde of exploited species
include Cattleya skinneri (the national flower of Costa
Rica), once locally abundant in rocky semideciduous
forests of the Pacific slope (H. Rockwell, pers. comm.).
Although the orchids have been exploited for many
years, we observed mature plants in the wild (some
with capsules) and juveniles within close reach, as
well as enormous plants in high canopies out of reach
of collectors. The exploitation tolerance of this popu-
lation is unknown, but remaining plants appear to be
reproducing and recolonizing. Removal of the forest
would pose the greatest threat to the orchid, as rock-
dwelling survivors would be targets for collectors.
Other orchids may be less able to sustain habitat
exploitation or collection. Rossioglossum schlieperi-
anum is a rare epiphyte in Monteverde, restricted to
large tree trunks exploited for lumber. Oncidium pan-
duriforme and Otoglossum chmquense occur natu-
rally in low densities and are vulnerable to habitat
loss. Rossioglossum schlieperianum and Otoglossum
chmquense could potentially be further imperiled by
commercial exploitation; the latter is virtually impos-
sible to cultivate. Despite its rarity, the relatively un-
attractive Oncidium panduriforme will probably never
be threatened by collectors in protected habitats.
One way to minimize collection of orchid species
vulnerable to collectors would be to flood markets
with plants that have been mass-produced from seed74 Plants and VegetationA