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Plant emergence from seed banks and from asexual reproduction could be strongly influenced by environmental and biological factors. Among environmental factors, animal disturbances deserve special consideration. In this study we test the hypothesis that disturbances resulting from the burrowing activity of Ctenomys affect plant emergence (sexual and asexual) in the south of the cold Puna desert. Richness and abundance of seedlings and sprouts growing in areas disturbed or undisturbed by Ctenomys were recorded at the beginning and at the end of the vegetative season. In general terms, the activity of Ctenomys does not affect richness of emerging species, but does have a significant influence on the type of emergence. Analyses between areas revealed that seedling emergence was significantly higher than sprout emergence in areas showing Ctenomys activity, whereas no significant differences were found between types of emergence in undisturbed areas. Although vegetative emergence was important, plant emergence from seeds appears to be relevant to the recolonization of areas disturbed by Ctenomys. [ABSTRACT FROM AUTHOR]

The effects of poaching on wildlife have been widely studied in conservation biology and can be heterogeneous, particularly on ungulates. These effects can be estimated through different methodologies whose use depends on several conditions such as Flight-initiation distance (FID). Our objectives were: 1- to evaluate whether poaching affects the FID and group structure of a guanaco (Lama guanicoe) population in a high cold desert in San Juan (Argentina); 2- to assess whether habitat structure (slope and vegetation cover) influences FID and group structure in this population. The study area included a site with poaching (unprotected area), and a site without poaching (protected area). We recorded 100 groups of guanacos: 70 in the protected and 30 in the unprotected area. FID and group size were greater in the unprotected than in the protected area, whereas proportions of group categories (with offspring, without offspring and solitary) were similar between areas. Besides, in relation to habitat structure, FID increased when vegetation cover decreased. On the other hand, FID and group size were not affected by slope. Our study shows that guanacos respond to poaching pressure as do other ungulate species, and that other factors such as vegetation cover also affect this behavior. Managers should be aware when interpreting FID due to its relation to habitat structure; the guanaco appears to assume greater risk (lower FID) in areas with high vegetation cover. [ABSTRACT FROM AUTHOR]