Disturbance and the role of refuges in mediterranean climate streams

High Variability Is a Defining Component of Mediterranean-Climate Rivers and Their Biota

“…Spawning migrations are common among native fishes (e.g., [52][53][54]), whereas other movements appear to be associated with adaptive behaviors to seek refugia or to colonize/re-seed habitats after severe droughts or floods (e.g., [49,55]). These latter movements may be may be especially important in Mediterranean systems with large seasonal and inter-annual variation in the magnitude, frequency, and duration of droughts and floods, which are areas where the distribution and quality of the available refuge pools can strongly influence the dynamics, persistence, and recovery of stream fishes [56,57].…”

“…If riffle habitats disappear, isolated pools are composed by communities that, over time, diverge from the original ones depending on local factors and stochastic processes [70] (Figure 4). If pools eventually dry up, lentic species disappear or become part of the river seedbank [24,57]. At the end of the dry period, flow resumption restores riffle habitats imposing new constraints for lentic species and promoting the re-colonization of riffle ones.…”

“…As a result of the high seasonality and inter-annual variability in flow, the intermittency of many streams, and the inherent variability in populations and communities, the establishment of defensible conservation targets in Mediterranean regions is especially difficult. The conservation of habitat refugia, and the maintenance of connectivity among them, are therefore important aspects to be integrated in the management of these highly variable systems [57]. This has been the approach used in freshwater conservation planning for the prioritization of highly seasonal sub-catchments in Northern Australia [140], and could also be used as a tool for improving conservation management in Mediterranean-climate regions.…”

Mediterranean-climate streams and rivers: geographically separated but ecologically comparable freshwater systems

“…In any 858 event, med-rivers will experience shifts in community richness and composition, 859 modifications of life-history traits, and, most likely will suffer local and regional 860 extinctions (Filipe et al, 2013). To avoid human disturbances, organisms in med-rivers may be able to find and 892 use refuges as they do with natural disturbances (Robson et al, 2013). However, some 893 disturbances may provide less evident refuges than others and many of them can last 894 much longer than the life span of species.…”

Drying Times: Integrating Citizen Science to Examine Survival of Florida Largemouth Bass in a Coastal Refuge Habitat

“…For example, Creek Chub, Semotilus atromaculatus, can escape drying in perennially interrupted Ozark streams by using seasonally-isolated pools that maintain high water quality via interstitial flows (Hodges & Magoulick 2011). Access to refuge habitats, such as dry season pools, buffer populations from drying events and are necessary for maintaining freshwater fish populations (Rolls et al 2012;Robson et al 2013;Avery-Gromm et al 2014). Changing flow regimes threaten the existence and function of refuges (Perry & Bond 2009).…”