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Birds in scrub habitats
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The Dartford Warbler and the Southern Grey Shrike are highlighted as the most endangered species of this environment.
IIn Spain,the patches of scrubland habitat vary in their structure depending on their altitude.Above the treeline, there are both areas of thorny bushes (leguminous plants like gorse) and other non-thorny scrub (broom,heather,etc.). The sub-montane zone is usually formed by tall and mediumsized bushes (e.g.broom and rock rose),which create a very distinctive type of habitat.At mid and low altitudes there are also large expanses of scrub with highly varied vegetation depending on the substrate,humidity,etc.Formations of juniper,gorse,kermes oak,broom and rock rose,are all important,extending in many cases down to sea level.
This kind of habitat is frequent across the whole of the Peninsula and the Balearic and Canary Islands, and, although it is better represented in the major mountain systems, it is also a significant part of the Mediterranean scrub in flatter areas.
Virgina Scandell ©
In SEO/BirdLife's SACRE programme, ten species typical of this habitat have been recorded. None of them showed any signs of a strong increase or decline and their overall trend is stable. However, two species, the Southern Grey Shrike and the Dartford Warbler, show a negative trend, not only at national level, but also in the four main regions in which the country has been divided. Both species have shown this trend for several years and, although the decline is moderate (-6.1% and -4.8%), their conservation status should be examined.
Region Average change (%) Trend
North 1,3 Moderate increase Centre -0,1 Stable East 0,4 Stable South 0,8 Moderate increase
© Luis Barrón Sylvia atricapilla
Changes in populations of common birds associated with scrub habitats,1998-2009.
According to the regions established, the analyses for the group of birds associated with scrub habitats show stable or positive trends.
Species Maximum Minimum Average change (%) Trend
Emberiza cia 1.8 -1.7 0.1 Stable Galerida theklae 5.1 0.9 3.0 Moderate increase (p<0.01) ** Hippolais polyglotta 3.7 1.1 2.4 Moderate increase (p<0.01) ** Lanius meridionalis -4.0 -8.2 -6.1 Moderate decline (p<0.01) ** Monticola saxatilis 1.1 -10.2 -4.6 Uncertain Prunella modularis 1.0 -2.8 -0.9 Stable Sylvia conspicillata 2.4 -8.3 -3.0 Uncertain Sylvia hortensis 9.9 2.7 6.3 Moderate increase (p<0.01) ** Sylvia melanocephala 0.8 -1.2 -0.2 Stable Sylvia undata -2.9 -6.7 -4.8 Moderate decline (p<0.01) **
Average annual changes and population trends of common birds associated with scrub habitats,1998-2009.
The censuses conducted in recent years for some less common species reveal the poor conservation status of some of them.The Eurasian Curlew is listed as ‘Endangered’,although in Spain it is at the limit of its range;its small population in Galicia could disappear through infrastructure development in its only known current breeding location.The Canary Islands Stonechat is classified as ‘Endangered’,although the latest estimated population is far superior to previous ones,possibly due to the change in census and analysis methods used for this species. For other taxa,such as the Grey Partridge,there is no updated information,so a specific census - never before conducted in Spain - is urgently needed.The only estimates, based on very limited censuses,indicate a population of 2,0006,000 individuals.Nevertheless,local monitoring has confirmed a severe decline in recent decades as a result of land use change and the fragmentation of its habitat.
