URBAN DITCH CHARACTERISTICS ASSOCIATED WITH TURTLE ABUNDANCE AND SPECIES RICHNESS

Although urbanization has contributed to wildlife population declines, urban ditches may present some of the last remaining refugia in expanding cities where turtles have persisted. To determine effective and easy-to-implement conservation measures, it is crucial to better understand the ecology of these urban turtle populations. Here, we assessed the influence of six easy-to-understand ditch characteristics on turtle abundance and richness using generalized linear mixed models. We based our study on capture and habitat data collected from May to August of 2011 and 2012, in seven ditches of Jonesboro, Craighead County, Arkansas, USA. Over these two years, we captured 452 turtles of six different species. Abundance and species richness were higher in ditches that were wider, longer, deeper, and had a wider buffer zone than ditches without these characteristics. No other variables (e.g., substrate type) were associated with variation in abundance or richness. Our results highlight the importance of habitat size for the persistence of turtle populations. Although other factors (e.g., water quality, food abundance) might be more ecologically relevant to urban turtles, ditch dimensions, being easy to manipulate, should be strongly considered when building or modifying a ditch system to minimize impact on turtle populations.