Animal metacommunities of temporary ponds in a flat grassland landscape of Uruguay

The database comprises a survey of an animal metacommunity of temporary ponds carried out in October 2008, in a grassland landscape of Uruguay. The animal groups involve macroinvertebrates, fishes, and amphibians. Individual occurrence, taxonomic affiliation, and traits associated with diet and body size are provided. The metacommunity is located in a flat landscape surrounded by hills, where a maximum of 61 ponds, every year, are filled with water in winter and dry out in summer in the same spatial locations. Information on species and morphospecies abundances at the sampling unit level was recorded in 18 ponds, the number of ponds that were active (i.e., with water) at the sampling date. These ponds are part of the metacommunity for which plants have been sampled every year since 2005 in all ponds and for which environmental information was also compiled—data available in this same Dryad entry. Further surveys are being processed and will be available in the future. Data are provided for promoting the advancement of metacommunity theory, corroborating published studies, and generating novel ones. We are incorporating all the available information about the studied metacommunity that now comprises 20 years of continuous monitoring. The database includes animal species and morphospecies abundances at the sampling unit level for 18 temporary ponds sampled in October 2008. The species traits related to body sizes (measured for each individual) and trophic guild (obtained from literature) are presented together with the individual taxonomy. Note that species Order or family can also be used as a proxy of many conserved attributes like life history, resistance strategy, dispersal mode, or vulnerability to predators.

Methods
In October 2008, ponds were sampled with a dipnet (15 x 20 cm, 1 mm mesh) through a standardised routine in which five equidistant samples were taken along the two main orthogonal axes of most of the ponds. To account for the range of pond areas, which exhibits differences in several orders of magnitude (from 6.6 m2 to 24,673 m2) when the quadrants were closer than two meters, the number of sampled units was reduced, and if the quadrants were more than 10 meters apart, then the number of sampled units was increased. The samples were washed, coarse separated, and preserved in 95% alcohol for identification. Individuals were classified with the highest possible taxonomic resolution. In cases where it was not possible to achieve a higher taxonomic resolution, individuals were assigned to taxa easily separable by morphological differences (i.e. morphospecies or the lowest possible hierarchy category). Each individual was measured with a digital caliper (to the nearest 0.01 mm).

Environmental data

Depth was measured at least 10 times in major and minor axes. The volume of the pond was estimated as the volume of an oval using the length of the major and minor axes of the ponds and the mean depth. Heterogeneity was estimated as the number of 'islands', emergent mounds above water level, per meter of the main and minor axes of the ponds. Vegetation biomass corresponds to standing biomass per unit sample—400 cm2 (20 x 20 cm). Vegetation species richness is the total richness of plants in a pond. The shape was approximated as the major/minor axis ratio. Geographical coordinates, latitude, and longitude of each pond were recorded.