Effects of terrestrial–aquatic connectivity on an estuarine turtle

• DOI: 10.1111/ddi.12289
• Publication Date: 2015-01-20T05:03:56Z
• Authors: Robert E. Isdell; Randolph M. Chambers; Donna M. Bilkovic; Matthias Leu
• Keywords: Occupancy; Ecotone

Abstract Aim Estuaries world‐wide have been modified or fragmented due to human stressors in their terrestrial and aquatic components. Estuary fragmentation often results reductions species richness, diversity connectivity. Effects of modification on estuaries well studied, but less is known about how land use alters connectivity the terrestrial–aquatic ecotone. We studied relationship between distribution an estuarine turtle, diamondback terrapin ( M alaclemys ). Location Chesapeake B ay, V irginia, USA . Methods conducted surveys at 165 sites from late spring mid‐summer 2012 2013. evaluated associations occurrence, use, salt marsh, shoreline armouring crabbing intensity concentric–circular neighbourhoods ranging 0.27 2 km cover daily annual movements. used occupancy modelling model averaging identify key variables explaining heterogeneity occupancy. final with independent data set identified occurrence thresholds for variables. Results Diamondback occupy areas ≥ 10% marsh within a 750‐m neighbourhood, ≤ 17% armoured 1‐km 20% agriculture 500‐m 33% low‐density housing 270‐m neighbourhood 9 active crab pots neighbourhood. Our performed when set. Main conclusions are first quantify negative alterations development, armouring, fishing activity. Because responses reflective changes coastal habitats, especially marshes, can be direct wetlands conservation restoration efforts.