Direct and Indirect Effects of Fire on Eastern Box Turtles

Abstract

Prescribed fire is an increasingly important management tool for eastern deciduous forests, but relativity little is known about the direct effects of fire on the eastern box turtle (Terrapene carolina carolina). We used very high frequency (VHF) transmitters to monitor mortality, movement, and spatial ecology of 118 box turtles in response to 17 prescribed fires across 4 seasons and 3 sites in east Tennessee, USA, during 2016–2018. Annual survival of box turtles that experienced a prescribed fire event was lower (0.87 ± 0.04 [SE]) than turtles that did not (0.98 ± 0.01) and was negatively correlated with fire intensity, fire temperature the turtle experienced, and litter depth. All prescribed fire‐related mortalities occurred during the early (Apr–May, n = 5) or late growing season (Sep–Oct, n = 1). Fourteen percent of box turtles we captured exhibited damage to their carapace from previous fire events. Box turtles that survived prescribed fires were in microsites that did not burn, moved to unburned areas during the fire, or burrowed following ignition. Home range size was similar before and after burns and sinuosity of movements did not differ in burned or unburned areas. Our results indicate that though box turtles are susceptible to prescribed fire during their active season, they have behavioral and physical traits that reduce the direct effects of prescribed fire. Prescribed fire practitioners should be aware of the risks of fire, particularly during the active season. We suggest managers consider altering prescribed fire intensity, seasonality, and firing pattern to minimize risk of direct effects where box turtles are of concern. © 2020 The Wildlife Society.

Spatial Ecology and Resource Selection of Eastern Box Turtles

“…Concealment in leaf litter or understory vegetation lessens the risk of evaporative water loss and can aid in maintaining a thermal optimum (Stickel 1950, Dodd 2001). Deeper litter layers, however, may lead to increased risk of mortality if prescribed fire is used to manage the vegetation type (Harris et al 2020). Box turtles are physiologically incapable of sustaining high body temperatures with temperatures of 24–32°C allowing for maximum activity (Adams et al 1989).…”

Fire management alters the thermal landscape and provides multi‐scale thermal options for a terrestrial turtle facing a changing climate

“…Over longer temporal scales, however, fire may be important for creating and maintaining the habitat that ectotherms require (Greenberg & Waldrop, 2008; Russell et al, 1999). In a study in Tennessee, box turtles did not exhibit selection for or against recently burned areas (Harris et al, 2020a). However, considering multi‐year burn history (time‐since‐fire) and a multi‐scale perspective may help towards understanding the thermal habitat selection of box turtles in relation to fire management.…”

“…In spring and fall, when temperatures are more moderate, box turtles may increase the use of grasslands (Reagan, 1974). It is unclear how fire management influences three-toed box turtles, although fire can be directly lethal to other box turtle species, particularly when fire intensities are high (Harris et al, 2020a(Harris et al, , 2020bJones et al, 2021;Roe et al, 2019). Over longer temporal scales, however, fire may be important for creating and maintaining the habitat that ectotherms require (Greenberg & Waldrop, 2008;Russell et al, 1999).…”

Shell histology of the Triassic turtle, Proterochersis porebensis Szczygielski & Sulej, 2016, provides novel insights about shell ankylosis

“…In addition, the Late Triassic was the time of increased incidence of wildfires compared to the Early and Middle Triassic, and the charcoal finds document not only surface, but even crown fires in the areas around the Poręba's paleonvironment (Kubik et al 2015). Modern tortoises and semiaquatic turtles are susceptible to fires, which may affect large parts of their population, and despite high death rates many individuals are able to survive, often with extensive injuries to the shells, sometimes right next to the scars from previous seasons (Babbitt & Babbitt 1951;Kuchling 1997;Harris et al 2020). The ability to regenerate is thus pivotal, particularly for long-living animals.…”