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| Where high species richness and high human population density coincide, potential
exists for conflict between the imperatives of species conservation and human development.
We examine the coincidence of at-risk bird species richness and human
population in the countries of the tropical Andes. We then compare the performance
of the expert-driven Important Bird Areas (IBA) scheme against a hypothetical
protected-areas network identified with a systematic reserve selection algorithm seeking
to maximize at-risk bird species representation. Our aim is to assess the degree to
which: IBAs contain a higher richness of at-risk species than would be expected by
chance, IBAs contain more people than would be expected by chance, and IBAs are
congruent with complementary areas that maximize species representation with an
equivalent number of sites. While the correlation of richness and population was low
for the region as a whole, representation of all at-risk bird species required many
sites to be located in areas of high human population density. IBA sites contained
higher human population densities than expected by chance (
P <
0.05) and were
markedly less efficient in representing at-risk bird species of the region than sites
selected using the reserve selection algorithm. Moreover, overlap between IBAs and
these latter sites was very limited. Expert-driven selection procedures may better
reflect existing sociopolitical forces, including land ownership and management
regimes, but are limited in their ability to develop an efficient, integrated network of
sites to represent priority species. Reserve selection algorithms may serve this end by
optimizing complementarity in species representation among selected sites, whether
these sites are adopted independently or as a supplement to the existing reserve
network. As tools of site selection, they may be particularly useful in areas such as the
tropical Andes where complex patterns of species disjunction and co-occurrence
make the development of representative reserve networks particularly difficult.
Furthermore, they facilitate making spatially explicit choices about how reserve
sites are located in relation to human populations. We advocate their use not in
replacement of approaches such as the IBA initiative but as an additional, complementary
tool in ensuring that such reserve networks are developed as efficiently as
practically possible. | |
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