waterfowl, parrots, and passerines, although the number of experienced personnel
is small.
Artificial incubation and hand-rearing provide supportive captive management
for clutch and brood manipulations. In established projects with experienced
personnel and good facilities, hatchability of fertile eggs is likely to reach 80%,
and rearing success 90% in many groups of birds.
12.7 Integrated management
Some of the most marked recoveries of critically endangered species entailed
a range of management practices, some of which were applied simultaneously. In
Table 12.1 the management procedures that were applied to the Mauritius
Kestrel, Pink Pigeon, Echo Parakeet, and Black Robin are all listed. All these
species recovered from tiny populations and management involved the whole
population.
The Mauritius Kestrel recovered from a wild population of four known birds
in 1974 to between 600 and 800 in early 2003; the Pink Pigeon from 10 wild birds
in 1990 to about 350 free-living birds in 2003, the Echo Parakeet from 8 to 11
known birds in 1987 to 175–200 free-living birds in 2003; and the Black Robin
from 5 birds in 1980 to about 300 in 2001. In all these species, the genetic vari-
ance in the tiny remnant populations must have been small, yet they recovered
to give large free-living populations (Groombridge et al. 2000). For some of
these, however, continued management may be necessary in the future.
12.8 Discussion
In effect, species are rare or declining because of poor productivity and/or
reduced survival, whatever the ultimate cause. The application of intensive
management techniques to small and declining populations offers high chances
of a rapid increase. However, because these techniques are intensive they are less
appropriate for use on widespread populations, and many of the most successful
examples are from relatively tame island species. Moreover, they are unlikely to
succeed long-term unless the ultimate causes of poor status are addressed,
whether these are loss of habitat and food supply, predation from people or intro-
duced predators, new diseases or other factors.
The application of techniques, such as fostering, and cross fostering of eggs
and young, works best with species that have high nest success (e.g. raptors,
cranes, and parrots). With many other species the levels of nest failure in the wild
are too high to justify the investment of time and energy. A broader approach to
population management is often more appropriate, including, for example,
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