Strong Spatial Influence on Colonization Rates in a Pioneer Zooplankton Metacommunity

Abstract

The magnitude of community-wide dispersal is central to metacommunity models, yet dispersal is notoriously difficult to quantify in passive and cryptic dispersers such as many freshwater invertebrates. By overcoming the problem of quantifying dispersal rates, colonization rates into new habitats can provide a useful estimate of the magnitude of effective dispersal. Here we study the influence of spatial and local processes on colonization rates into new ponds that indicate differential dispersal limitation of major zooplankton taxa, with important implications for metacommunity dynamics. We identify regional and local factors that affect zooplankton colonization rates and spatial patterns in a large-scale experimental system. Our study differs from others in the unique setup of the experimental pond area by which we were able to test spatial and environmental variables at a large spatial scale. We quantified colonization rates separately for the Copepoda, Cladocera and Rotifera from samples collected over a period of 21 months in 48 newly constructed temporary ponds of 0.18–2.95 ha distributed in a restored wetland area of 2,700 ha in Doñana National Park, Southern Spain. Species richness upon initial sampling of new ponds was about one third of that in reference ponds, although the rate of detection of new species from thereon were not significantly different, probably owing to high turnover in the dynamic, temporary reference ponds. Environmental heterogeneity had no detectable effect on colonization rates in new ponds. In contrast, connectivity, space (based on latitude and longitude) and surface area were key determinants of colonization rates for copepods and cladocerans. This suggests dispersal limitation in cladocerans and copepods, but not in rotifers, possibly due to differences in propagule size and abundance.

How do freshwater organisms cross the “dry ocean”? A review on passive dispersal and colonization processes with a special focus on temporary ponds

“…By studying zooplankton colonization rates and spatial patterns in a large-scale experimental system of ponds in the Doñana National Park (Southern Spain), Frisch et al (2012) found that, in accordance to the theory of island biogeography (MacArthur & Wilson, 1967), connectivity, spatial distance among ponds and surface area of the studied water bodies (target-area effect: larger surfaces are better receivers of inocula, see Lomolino, 1990) were key determinants of colonization rates for crustacean zooplankton. Conversely, in a study carried out in a network of temporary ponds, Eitam et al (2004) found that crustacean species richness was positively related to hydroperiod length but not to surface area.…”

Relative importance of environmental, geographic, and spatial variables on zooplankton metacommunities

“…The current study adds to a growing body of literature concerning the mechanisms structuring species distributions (Frisch et al 2012, Heino et al 2012, Peres-Neto et al 2012. Specifically, this study offers a novel way to analyze community data to address the relative impact of variables v www.esajournals.org belonging to different classes.…”

Stability in Planktonic Rotifer Assemblages Found in Four Old Diversified Forest Ponds of Eastern Poland

“…The samples were collected by taking 10 dm 3 of water with the use of a Toń II sampler at a depth of 0.5 m. The water collected in this way was sieved through a planktonic net No. 25 and condensed to a constant volume of 100 cm 3 . The samples were preserved with Lugol's liquid and 4% formaldehyde and glycerine solution.…”

“…Consuming bacteria, algae, protozoa, and dead organic matter, they play a signifi cant role in the trophodynamics of these water ecosystems, and they inhabit them relatively early [3][4][5]. Many of them react quickly to any changes in water fertility or purity [1,[6][7].…”