The alarming pace of tropical biodiversity loss requires development of inn
ovative approaches for in situ biodiversity conservation. Incentive-based a
pproaches have emerged as one possible option. We interviewed 68 private na
ture reserve owners to learn more about one of Costa Rica's incentive progr
ams. The interview group included all reserve owners participating in the g
overnment's Private Wildlife Refuge Program (n = 22) and a control group of
nonparticipating owners (n = 46). Quantitative and qualitative data led to
seven main conclusions on the use of incentive programs: (1) a developing
country can expand and enhance its formal park system through conservation
incentives; (2) insufficient promotion, and resulting information gaps, can
prevent an incentive program from realizing its full potential; (3) landow
ners enter a program not only in response to the intended incentive package
, but also for several powerful and hidden incentives such as publicity and
marketing purposes; (4) underutilization of official incentives by partici
pants, in part due to sporadic delivery of incentives by the government, ca
n undermine program effectiveness; (5) biodiversity protection goals can be
accomplished by means of a wide range of incentives; (6) programs that req
uire only a short-term commitment by landowners can still lead to long-term
biodiversity protection; and (7) a program can produce unanticipated negat
ive consequences at the national level, including putting conservation at o
dds with social justice. These and other lessons on the use of incentives s
hould be of interest wherever biodiversity is threatened, wherever new cons
ervation partners are being sought and wherever incentive-based approaches
are being considered.