ERRATUM (1). In the original published version of this manuscript, there was an error in the second sentence of the second paragraph of the Introduction.

The corrected sentence appears in full below.

It is a highly diverse system (De Miguel 1999, Carrión et al. 2000); tree cover does not follow a uniform pattern, as it usually results from natural regeneration, and the varying tree density suggests that these human-made agro-ecosystems have adjusted to local climate (Joffre et al. 1999).


ERRATUM (2). In the original published version of this manuscript, there were errors in the first and second sentences of the third paragraph of the Introduction.

The corrected sentences appear in full below.

Recently, several authors have stressed the need to analyze and quantify the relationships between anthropogenic and non-anthropogenic factors in shaping ecological communities (Allen and O'Conner 2000, Yeo and Blackstock 2002). Montados have been managed by humans for a long time (Joffre et al. 1999)-Iberian Romans reputedly bred pigs under evergreen oaks-and are listed in the Appendix I of the European Community Habitats Directive (92/43/CEE): they are, therefore, especially suited to be the subject of an investigation on the nature vs. nurture issue (Lavorel et al. 1998).


ERRATUM (3). In the original published version of this manuscript, there was an error in the first sentence of the fifth paragraph of the Introduction.

The corrected sentence appears in full below.

Previous studies have found a relatively high richness in montado bird diversity compared with other ecosystems (Araújo et al. 1996).


ERRATUM (4). In the original published version of this manuscript, there was an error in the last sentence of the fifth paragraph of the Introduction.

The corrected sentence appears in full below.

At a regional level, some authors have described biogeographic, environmental, and anthropogenic factors as determinants of plant diversity (see Rey Benayas and Scheiner (2002) for the Iberian Peninsula and Yeo and Blackstock (2002) for Great Britain).


ERRATUM (5). In the original published version of this manuscript, there was an error in the last sentence of the first paragraph of the Introduction.

The corrected sentence appears in full below.

In this paper, we investigate patterns of plant and bird distribution across the 1,175,000-ha area covered by montados in southern Portugal (Direção-Geral das Florestas 2001).


ERRATUM (6). In the original published version of this manuscript, there were errors in the fourth and fifth sentences of the first paragraph of the Study Area and Site Selection section of the Methods.

The corrected sentences appear in full below.

Sites were selected using an 8 x 8 km grid generated over the European Community Forestry Monitoring 16 x 16 km grid with the help of a geographic information system (GIS). Laying this grid over a land-use map, we were able to choose 100 intersections at random as potential sites, verified them all in the field, and selected 30 that were cork oak-dominated montados and 30 others that were holm oak-dominated montados.


ERRATUM (7). In the original published version of this manuscript, there was an error in the first sentence of the first paragraph of the Data Collection section of the Methods.

The corrected sentence appears in full below.

One way to analyze the impact of human activities on montados is to identify and quantify the agro-economic activities (cork harvesting, herding, and cereal cultivation, for example) that characterize each site.


ERRATUM (8). In the original published version of this manuscript, there was an error in the first sentence of the first numbered paragraph (The Bio set) under the Data Collection section of the Methods.

The corrected sentence appears in full below.

Two biological groups were surveyed: plants (species composition and percentage of cover intensively surveyed within a 100-m circle centered on the sampling site centroid, plus identification of all species on a transect within a 1-km radius) and birds (three point counts per 1-km radius circle, twice in spring and once in winter in 2 consecutive years).


ERRATUM (9). In the original published version of this manuscript, there were errors in the second and third sentences of the fourth numbered paragraph under the Data Analysis section of the Methods.

The corrected sentences appear in full below.

One variable was eliminated (us-la: stream vegetation land-use) because the sampling procedure adopted for birds (point counts) excluded it. An equal number of variables in each group ensured that the three sets of explanatory variables could be compared without fear that their variance could be related to the number of variables within each set (following Paszkowski and Tonn 2000); subsequent analyses used only 24 variables.


ERRATUM (10). In the original published version of this manuscript, there were errors in the first and second sentences of the first paragraph of the Results.

The corrected sentences appear in full below.

The Bio set comprises 14 000 plant specimens (596 species) and 17 000 sightings of birds (128 species). The explanatory variables collected amounted to 79 (Table 1); this number was reduced to 24 (Table 3) in subsequent analyses (other authors have successfully reduced a larger set of variables to seven, in order to standardize groups of factors in partial RDA; see Paszkowski and Tonn 2000).


ERRATUM (11). In the original published version of this manuscript, there was an error in the last sentence of the third paragraph under the Analysis of Total Variance section of the Results.

The corrected sentence appears in full below.

As with plants, the physical structure of the ecosystem and ecological variables seemed to be the main drivers of bird distribution.


ERRATUM (12). In the original published version of this manuscript, there was an error in the third sentence of the first paragraph under the Patterns of Richness and Composition section of the Discussion.

The corrected sentence appears in full below.

Our results clearly showed that, in the case of montados, a conservation strategy aimed at protecting plants would not necessarily protect bird species, and vice versa.


ERRATUM (13). In the original published version of this manuscript, there was an error in the second sentence of the second paragraph under the What Makes One Montado Different from Another section of the Discussion.

The corrected sentence appears in full below.

Our partitioning of variance had a ratio "interaction : pure variance" of 1:3 (Yeo and Blackstock (2002) obtained a ratio of 7:5), which accounted for the independent character of the three groups of variables, the independent variance of each group being much higher than the interaction between all groups, indicating that they are clearly separable in their effects (Borcard et al. 1992).


ERRATUM (14). In the original published version of this manuscript, there was an error in the last sentence of the third paragraph under the Which Variables Most Affected Plant and Bird Distribution section of the Discussion.

The corrected sentence appears in full below.

The variable ab-spz can also act as a surrogate for the proximity and influence of the large Tagus river basin, where most podzol sites are located.


ERRATUM (15). In the original published version of this manuscript, there was an error in the seventh sentence of the fourth paragraph under the Which Variables Most Affected Plant and Bird Distribution section of the Discussion.

The corrected sentence, which should begin a new paragraph, appears in full below.

In addition to the cork extraction variable explained above, five other anthropogenic variables seemed to affect plant distribution (Table 3).


ERRATUM (16). In the original published version of this manuscript, there were errors in the fifth paragraph under the Which Variables Most Affected Plant and Bird Distribution section of the Discussion.

The corrected paragraph appears in full below.

The only land use related to plants was forestry. Local plantations are dominated by the maritime pine (Pinus pinaster) and the Eucalyptus (Eucalyptus globus). Pine forests are home to many plant species not found in montados. Eucalyptus trees, however, usually prevent other plant species from establishing in eucalyptus plantations. In both cases, forestry affects plant turnover. Birds are also affected by forestry, for the same reasons given above and because there are bird species specific to pine forests. Almost all bird species avoid Eucalyptus forests.


ERRATUM (17). In the original published version of this manuscript, there was an error in the last sentence of the sixth paragraph under the Which Variables Most Affected Plant and Bird Distribution section of the Discussion.

The corrected sentence appears in full below.

Despite its exclusion from the final set of variables (because bird sampling did not include this habitat), we think that it provides interesting results for plants; an improved sampling procedure could possibly provide the same good results for birds.


ERRATUM (18). In the original published version of this manuscript, there was an error in the first sentence of the seventh paragraph under the Which Variables Most Affected Plant and Bird Distribution section of the Discussion.

The corrected sentence appears in full below.

Differences among the Ae variables are mainly due to management options, and these are not based on geographic grounds.


ERRATUM (19). In the original published version of this manuscript, there were errors in the eighth paragraph under the Which Variables Most Affected Plant and Bird Distribution section of the Discussion.

The corrected paragraph appears in full below.

Given their more diverse responses to anthropogenic variables (see Table 3), plant and bird distribution throughout the montado landscape is best predicted by ecological variables.


ERRATUM (20). In the original published version of this manuscript, there were errors in the first and second sentences of the first paragraph under the How Do Individual Species Make up Patterns of Distribution section of the Discussion.

The corrected sentences appear in full below.

There was a clear asymmetry in plant response to geographic coordinates, with the highest abundance of species in the south and the west and a gradual impoverishment toward the north and the east (Table 4; Appendix 2). As a result of this asymmetry, richness measures in west vs. east montados and south vs. north montados are not comparable; differences in diversity might even be a "natural" pattern.


ERRATUM (21). In the original published version of this manuscript, there was an error in the third sentence of the second paragraph under the How Do Individual Species Make up Patterns of Distribution section of the Discussion.

The corrected sentence appears in full below.

A possible explanation for this result is that plant gradients along geographical coordinates are more prone to fit a non-linear response.


ERRATUM (22). In the original published version of this manuscript, there was an error in the fifth sentence of the second paragraph under the How Do Individual Species Make up Patterns of Distribution section of the Discussion.

The corrected sentence appears in full below.

This reflects a good fit of birds to the linear model (thus RDA gave good results for birds); at the same time, plants, approaching the unimodal model (better GLM models), showed a preference for a linear response (the empirical limit to consider a good adjustment to the unimodal model is a gradient length greater than 3 s.d.: Jongman et al. 1995).


ERRATUM (23). In the original published version of this manuscript, there was an error in the sixth sentence of the second paragraph of the Speculation.

The corrected sentence appears in full below.

None of the studied montados looked degraded (although it was not our intent to study sustainability, therefore, we have no measurable definition of degradation), in which case these species would indicate montados that have been sustainably exploited, that is, their presence could be taken as a measure of sustainability.


ERRATUM (24). In the original published version of the Literature Cited section of the manuscript the following citation was omitted:

Araújo M. B., R. Borralho, and C. Soate. 1996. Can biodiversity be measured using composite indices? Pages 124-128 in J.C. Farinha, J. Almeida, and H. Costa, editors. Proceedings of the 1st Congress of Ornithology of the Portuguese Society for the Study of Birds, November 1-3, 1994, Vila Nova da Cerveira, Portugal.