Wind mediated dispersal of freshwater invertebrates in a rock pool metacommunity: differences in dispersal capacities and modes

Abstract

Current evidence suggests regular overland transport of different freshwater invertebrates by wind, mainly over short distances. Yet, very little is known about the mechanism and scale of this process or about differences in wind dispersal dynamics and capacities among taxa and propagule types. We investigated wind dispersal of freshwater invertebrates in a cluster of temporary rock pools (spatial scale: 9,000 m 2 ) in South Africa. Dispersing propagules and propagule bank fragments (i.e. aggregates of sediments and propagules) were intercepted during 1 month using a combination of windsocks (1.5 m above ground level) and sticky traps (ground level). The potential movement of propagule bank fragments (i.e. aggregates of propagules and sediments) was also simulated by tracking inter-pool movements of differently sized artificial substrate fragments similar to dry propagule bank fragments. We detected differences in the composition of dispersing communities intercepted at different altitudes (ground level and at 1.5 m). Comparison of dispersal distance distributions also revealed significant differences among taxa. Overall, larger propagule types (e.g. adult ostracods and oribatid mites) dominantly travelled near ground level while small resting eggs and cryptobiotic life stages of copepods were most frequently collected at higher altitudes (1.5 m) and dispersed over the longest distances. Finally, not only dispersal of single propagules but also ground level transport of propagule bank fragments was shown to contribute to local dispersal dynamics in temporary aquatic habitats.

Fine-scale spatial genetic structure and within population male-biased gene-flow in the grasshopper Mioscirtus wagneri

“…Such a similar male-biased dispersal pattern has been previously found in the Mormon cricket (Anabrus simplex) (Bailey et al 2007; but see Lorch et al 2005;Sword et al 2008). A possibility to explain this pattern is that female-biased predation has resulted in the observed male-biased dispersal even if both sexes tend to disperse equally (Palo et al 2004) or that the smaller male size favours wind mediated passive male-dispersal (Robbins and Small 1981;Havel and Shurin 2004;Vanschoenwinkel et al 2009). Other possibility is that the inferred male-biased dispersal pattern has evolved due to inter-male competition for mates (Greenwood 1980).…”

Dormancy in metacommunities

“…Microcrustaceans, such as cladocerans, copepods, and fairy shrimp, have 422 a broad range of dispersal (Jenkins and Buikema 1998;Cáceres and Soluk 2002;Vanschoenwinkel et al 2009) and dormancy capabilities (Brendonck et al 2016;Ellegaard and 424 Ribeiro 2018). For example, the production of dormant ephippia in response to food limitation, crowding, or seasonality (Fig.…”

Hatching phenology, life history and egg bank size of fairy shrimp Branchipodopsis spp. (Branchiopoda, Crustacea) in relation to the ephemerality of their rock pool habitat

“…In that study, a lower variance in egg densities was measured over a period of 4 years in pools with vegetation compared to pools without vegetation. Additional information was provided by Vanschoenwinkel et al (2009b), who measured high dispersal rates, not only of resting eggs but also of resting egg bank fragments in this study system. The authors also hinted at the potential of aquatic vegetation to decrease wind erosion of the egg bank.…”