Regional Dynamics of Wetland‐breeding Frogs and Toads: Turnover and Synchrony

Abstract

We used data from a statewide frog monitoring network to investigate population turnover and synchrony in eight wetland‐breeding species. We found that subpopulations at many sites turn over frequently, with breeding choruses absent or undetectable in most years. Frequencies of detection across sites were significantly associated with the density of wetland patches (all species) and the areal extent of several terrestrial land cover categories (seven species) within 1 km. Intraspecific population fluctuations were statistically synchronized between survey sites separated by up to 50–100 km, but synchrony was not strong. Anuran abundances were significantly correlated with rainfall 1–4 years earlier, indicating that rainfall influences population fluctuations. However, population synchrony was much weaker than rainfall synchrony. Managers attempting to maintain amphibian populations regionally should focus on maintaining landscapes with high densities of wetlands and sufficient upland habitat resources. The dynamic nature of amphibian populations at individual wetlands is well known, and our results suggest that species distributions at the landscape level are similarly dynamic.

Quantifying the Road-Effect Zone: Threshold Effects of a Motorway on Anuran Populations in Ontario, Canada

“…A major, unexpected result of this study was the strength of the negative relationships between distance to the highway and relative abundance we found for five species that have previously been shown to be relatively unaffected by roads and traffic, i.e., the spring peeper, chorus frog, wood frog, and, to a lesser extent, the gray treefrog and green frog (Carr and Fahrig 2001, Trenham et al 2003, Weyrauch and Grubb 2004, Mazerolle et al 2005, but see Houlahan and Findlay 2003). Indeed, in an earlier study examining the relative effects of traffic and forest cover at the landscape scale in the same region, but not focused on Highway 401, we did not find significant effect of traffic for any of the above species (Eigenbrod et al 2008a).…”

Road Impacts on Abundance, Call Traits, and Body Size of Rainforest Frogs in Northeast Australia

“…Although studies have examined road impacts in tropical rainforests (Goosem 2007, Laurance et al 2009), effects on rainforest frogs have received little attention. Roads in temperate habitats can reduce amphibian species richness and abundance (Fahrig et al 1995, Trenham et al 2003, Pellet et al 2004a, 2004b, Parris 2006, Eigenbrod et al 2008, Fahrig and Rytwinski 2009, with road mortality believed to be the primary impact (Fahrig et al 1995, Fahrig andRytwinski 2009). Of particular interest is the potential effect of traffic noise on frogs.…”

Spatial synchrony of wader populations in inland lakes of the Iberian Peninsula

“…In other words, regardless of the size of the 67 local population, two or more sites are synchronized if 68 the curves of abundance of both sites are coupled. 69 Spatial synchrony is one of the most important patterns 70 in metapopulations dynamics, being observed at differ-71 ent scales (local, regional and global), as well as in many 72 species groups (Holyoak and Lawler 1996;Thrall et al 73 2001;Post and Forchhammer 2002;Trenham et al 2003; 74 Liu et al 2009;Batchelder et al 2012;Kvasnes et al 75 2013). 76 In general, spatial synchrony of abundance has been 77 associated to three ecological processes, which can act 78 independently or in combination: dispersal of individu-79 als, environmental conditions and trophic interactions…”