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The Natura 2000 network (N2K) was designed using species and habitats annexed in the European Union's (EU) Directives of Birds (BD) and Habitats (HD). The selection of such species receives increasing criticism, as does the frequent use of design methods not based on Systematic Conservation Planning (SCP). As a result, a proportion of the EU's biodiversity may remain uncovered by the network, irrespective of the degree of coverage of the annex species. Data limitations currently prevent rigorous EU‐wide gap analysis for multiple biodiversity components simultaneously (i.e., taxonomic groups, conservation attributes and organizational levels), but regional data at finer resolutions may add evidence of the breadth of the umbrella effect to be expected. We tested the hypothesis that an objectively designed N2K may confer the EU´s annex species an umbrella effect over multiple biodiversity components. This conjoint analysis of multiple taxa, attributes and levels is rarely done. We used distribution data of terrestrial vertebrates and invertebrates in one of the richest regions in the EU (Extremadura, Spain), whose reserves and biodiversity surpass many EU countries, and where the N2K was designed through SCP. We implemented a gap analysis explicitly including annex species status, conservation‐relevant attributes (rarity, endemicity and vulnerability) and organizational levels (species, richness and hotspots). The annexed species acted as an umbrella group at the species, richness and hotspot levels, successfully covering rarity, endemicity and vulnerability. Our results show that the set of species that currently forms the EU's directives annexes has a wide umbrella potential, at least where objective SCP methods were used for reserve design. We suggest that, under such conditions, N2K design could essentially remain constant within a context of changing threat status, the challenge of conservation resting more on management measures than on redesigns of the network. [ABSTRACT FROM AUTHOR]

The germination of seeds of Eichhornia crassipes in locations distant from the foci of infestation may be a means of dispersal of this invasive plant. Nonetheless, no modern studies have examined the influence of single components on germination, although the influence of temperature, oxygen and redox potential was examined in earlier studies. The effects of pH, conductivity, nitrate, phosphate, potassium, calcium, iron and boron on germination of E. crassipes were determined in seed germination tests. The results showed that external input of nutrients influences germination, since neither pH nor conductivity alone had any effect, but there was a significant increase in germination in growth media containing phosphorus at 3.95 mg·l (P/L; 95.5%) and boron at 10 mg·l (B/L; 97.5%); at higher concentrations, the latter was toxic. These findings contribute to knowledge of factors controlling the germination of E. crassipes seeds. Consequently, E. crassipes seeds would find very good conditions for germination in water classified as hypereutrophic, which may play a decisive role in expansion of this plant. [ABSTRACT FROM AUTHOR]

The evolution of 40 wintering areas of Grus grus in the south-west of the Iberian Peninsula has been studied, including the traditional wintering places of this species on its western route. Eight of these areas harboured 50% of the whole population using this route, and none of the 40 areas showed a decline in the number of birds during the study period. At present the number of cranes in each area is much greater than in the 1979–1980 winter. No geographical trends have been observed regarding the magnitude of the increase, which is closely related to that observed for the whole Spanish and Palearctic populations. Despite the emergence of some new wintering areas, the magnitude of the increase is greater in more southerly parts of the range. This may be a consequence of greater diversity and availability of food in these latitudes. The influence of enhanced international protection and agricultural food sources on the appearance of new wintering areas is discussed. [ABSTRACT FROM PUBLISHER]

We study the usefulness of the haematocrit as a predictor of body condition in birds, using a captive population of the endangered species Northern Bald Ibis (Geronticus eremita). This population is 14% of the worldwide captive population, which is far greater than the known free-living population. The haematocrit, body mass and body condition index responded in the same sense to two different nutritional periods, and there was a statistically significant relationship between changes in condition index and haematocrit of individual birds between the two periods. We discuss the relationship of these parameters with subcutaneous fat and muscle mass, and analyse the individuals' nutritional status in each of the periods studied. The conclusion was that the haematocrit is sensitive to variations in body condition since it responds to mass-loss processes corresponding to phases of mobilization of fat reserves, a situation prior to the mobilization of muscle proteins when there is a manifest deterioration of the individual's aspect.