Effects of Fire on Amphibians & Reptiles

Transcription

1 Effects of Fire on Amphibians & Reptiles Tami S. Ransom Dept of Environmental Studies Salisbury University January 30,

2 Outline Overview Activity patterns of herpetofauna in MD What we know: Case studies of effects of prescribed burns on reptiles & amphibians Resources & recommendations 2

3 Overview Effects of fire will vary among Geographic regions Habitats Taxa Species within a taxa 3

4 Overview Reptiles & amphibians are often grouped together as herpetofauna Different life histories Different responses to fire 4

5 Activity patterns of Herpetofauna in Maryland 5

6 Frogs 6

7 Thin lines = larval period Salamanders 7

8 Turtles 8

9 Lizards 9

10 Snakes 10

11 What we know: Case studies 11

12 Fire effects on herpetofauna Most data from the Midwest, Appalachian Mountains, or Southern Coastal Plain (longleaf pine forest) Often data short-term studies of burned vs. unburned areas Type & frequency of fire regime important Results often differ among studies 12

13 Case Study: Cold Mountain Gameland NC Greenberg & Waldrop 2008 Treatments control mechanical understory reduction + herbicide prescribed burn (2009 & different sites) mechanical + burn 13

14 Effects on terrestrial salamanders No effect of prescribed burns; note = mark-recapture with few to no recaptures, 14

15 Effects on lizards Mechanical + burn = increase in lizard abundance 15

16 Case study: William B. Bankhead NF Alabama (Sutton 2010; Sutton et al. 2013) Upland sites with oak-hickory & loblolly pine Treatments: Thinning: none, 11 m 2 /ha residual basal area [BA], or 17 m 2 /ha residual BA No burn or burn low-intensity fires completed during the dormant season (January February) Low air temps, high relative humidity 16

17 Effects on lizards Lizard counts were greatest two years after treatment in all thinned+burn plots 17

18 Effects on Snakes Copperhead, Black Racer, eastern king snake Total large snake counts greatest in thin-only plots; marginally significant burn effect (F 1, 36 = 3.80; p = 0.059) 18

19 Frogs found = Green frog, southern leopard frog, pickerel frog, & bullfrog true frog counts increased considerably and were highest during the second year posttreatment in control plots 19

20 declined across all treatments through all years 20

21 Effects on Michigan study (Gibson 2007; Kingsbury & Woodley unpub.) Eastern box turtles= mortality rate of 10-20% Injuries also occurred which may => future mortality Behavioral shifts 21

22 Case Study: Chesapeake Farms MD McLeod & Gates (1998) Atlantic Coastal Plain hardwood (Hardwood), cut-over hardwood (Cut), mixed pinehardwood (Pine) and prescribed burn pine (Burn annually since 1981). Amphibians: Captures lower in burned vs. unburned stand for: total amphibians (74 vs. 391) salamanders (8 vs. 105) ranids (6 vs. 20) frogs and toads (66 vs. 214). Reptiles: Most species less abundant burned vs. unburned stand (96 vs. 130). Two species (racer & kingsnake) were more abundant in the burned vs. unburned stand 22

23 Resources & recommendations 23

24 Prescribed Burning Guidelines for Herpetofauna Identify the herpetofaunal diversity of your site prior to large scale management 24

25 Think about what species are in the area Burns near wetlands may interfere with salamander breeding migrations Winter fires can also expose hibernating frogs and terrestrial salamanders Early spring burns in forests may harm Eastern Box Turtles emerging from hibernation Later spring and early summer burns may impact turtles laying eggs 25

26 Think about what species are in the area Spring burns in close proximity to snake hibernacula should be conducted well before the active season or not at all 26

27 Prescribed Burning Guidelines for Herpetofauna Often it is best to burn during late fall or winter months when most herps are inactive The intensity and speed of the flames should be adjusted and controlled to accommodate the herpetofaunal species present in the habitat Repeated burns will have cumulative effects on population viability 27

28 Few long-term studies Bottom line Few direct impacts of fire on amphibians & reptiles Know the species in your area & their habits 28

29 Well-planned fires = healthy communities umog 29