La avutarda hubara - SEO/BirdLife

Summary
In all cases, the number of birds present in primary habitats is larger than the
number of individuals in secondary areas. The percentage of birds in the latter
has increased as compared to previous censuses; the 1994 rate was 26.70%, and
the current value is 40%. Therefore, the increase in population in marginal areas
which seems directly linked to the loss and degradation of primary habitats
occurred between the mid-1990s study and the most recent one, with the decrease
of suitable area being 162,50 to 145,37 km 2 . Nonetheless, the improvement
in the census efforts on such habitat types during the most recent surveys should
also be taken into account when appraising the results.
The recommendation as regards the census method is to implement multi-line
transects. Endeavouring to this approach would facilitate comparisons with
the large amount of information gathered to date in previous censuses
through this methodology. The new features incorporated into the recent census
campaigns consist of (1) recruiting two census teams to survey the two
main islands simultaneously, thus reducing the overall census period; (2)
enlargement of the study area to include a larger number of secondary habitat
sites occupied by the species.
The conservation status of the Houbara Bustard has been reviewed under the
IUNC Red List criteria (3.1 version) on the basis of the census results. As in the
Red Data Book for Spain’s Birds, the revision has not involved the application of
regional corrections, after the premise that the species population is isolated,
and made up of the individuals of the three main islands where the species is
present. The assessment result is that the species qualifies as “Endangered”
under criterion B1ab(iii)+B2ab(iii).
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