P. Ferreras et al., Restore habitat or reduce mortality? Implications from a population viability analysis of the Iberian lynx, ANIM CONSER, 4, 2001, pp. 265-274
Managers trying to preserve populations of endangered carnivores are often
forced to choose between restoring habitat to allow larger breeding populat
ions or reduce risks of mortality to increase survival rates. We modelled t
he viability of a metapopulation of the Iberian lynx (Lynx pardinus) under
several scenarios (habitat restoration, anti-poaching, reduction in road ki
lls) in a real landscape to evaluate their relative effects, Increasing car
rying capacity was highly effective when per-formed on the local population
s that acted as sources but had no effect when carried out in the sinks. Re
alistic scenarios consisting of partial removal of the human-related mortal
ity (assuming additive effects of causes) predicted high risk of extinction
. When combined, the effects of both management options are highly dependen
t on where they are carried out. If the sinks are the only targets of carry
ing capacity enlargement, a complete removal of human-caused mortality is r
equired, whereas increases in the carrying capacity of sources are always e
ffective. The metapopulation risk of extinction decreases dramatically (fro
m 45.5% to 2.1%, in 100) if connectivity among source populations can be im
proved. According to our work, only a detailed knowledge of the spatial and
demographic structure of the populations, combined with simulations of rea
listic situations, can help managers to select the a priori optimal strateg
y, which probably combines different management options.