Community structure of fishes inhabiting aquatic refuges in a threatened Karst wetland and its implications for ecosystem management

Trait Variation in an Everglades Invasive Species: Life histories, Boldness, and Dispersal in the African Jewelfish

“…In this assay, I characterized the repeatability of boldness, as well as the dispersal tendency of the subjects by giving them the opportunity to explore and move into a new area of the experimental setup (Figure 3b). Movement from the emergence tank to the second tank through the connecting channel (Figure 3b) mimics the movement of Everglades fishes in and out of dry-down refugia as water level fluctuate seasonally (Kobza et al, 2004).…”

“…The marsh area that was first invaded and inhabited the longest by jewelfish is a karst graminoid wetland with relatively short-hydroperiod (5-6 months of flooding over the year) (Kobza et al, 2004). Because of the short duration of flooding, these habitats are predator-limited (Chick et al, 2004), and community structure is dominated by small poeciliids, centrarchids, and other nonnative cichlids (particularly juvenile Mayan cichlid, Cichlasoma urophthalmus, and Black Acara, Cichlasoma bimaculatum; Kobza et al 2004). The marsh surface is also dotted by a mosaic of depressions in exposed limestone outcroppings (from a few cm to > 60 cm deep) (Loftus 2006).…”

“…The marsh surface is also dotted by a mosaic of depressions in exposed limestone outcroppings (from a few cm to > 60 cm deep) (Loftus 2006). Solution holes serve as important dry season refugia for many aquatic organisms (Kobza et al, 2004;Ruetz et 7 al., 2005). Seasonal movement by fishes in and out of these dry-down refugia (and others, e.g., alligator holes, mangrove creeks; Palmer andMazzotti 2004, Rehage &) is critical to individual survival and population persistence (Chick et al, 2004;Obaza et al, 2011).We expect dispersal to be an adaptive trait for Everglades native fishes, as well as for recently arrived non-native taxa.…”

Examining Gradients in Novelty: Native and Non-native Fish Assemblages in Everglades Canals

“…In pulsing systems, seasonal variation in rainfall drives patterns of inundation and thus habitat availability for fishes and other aquatic taxa, such that fish survival is highly dependent on refuge size, the intensity of the drydown period and mobility (Magoulick and Kobza 2003). The recurrent pattern of seasonal drying in Everglades marshes is a major driver of fish community dynamics as fish move to both natural (i.e., alligator holes, solution holes and estuarine mangrove creeks (Loftus and Kushlan 1987;Kobza et al 2004;Rehage and Loftus 2007;Parkos et al 2011;Rehage and Boucek 2013), and artificial (i.e., canals, Rehage and Trexler 2006) deep refuges as water levels recede. We saw further evidence of the use of canals as drydown habitat in this study, but the timing varied among canal types, matching the hydroperiod of surrounding marshes.…”

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

“…Survival is a key determinant of population dynamics (Varley & Gradwell 1960;Buzby & Deegan 2004), and the ability for ecologists to link vital rates to environmental factors provides a powerful tool to investigate how natural populations respond to changing patterns of disturbance (Frederiksen et al 2008;Frederiksen et al 2013). Although a number of studies have begun incorporating variation in refuge quality to understand the interplay between disturbance and refuge habitats (Kobza et al 2004;DeAngelis et al 2010;Parkos et al 2011;Bond et al 2015), few directly quantify survival. Instead, most studies infer survival through changes in relative abundance over time, which can be problematic, as heterogeneity in the probability of individual detection across varying habitats creates an inherent bias (Williams et al 2002).…”