Predation by Coyotes on White-Tailed Deer Neonates in South Carolina JOHN C. KILGO,1'2 USDA Forest Service, Southern Research Station, P.O. Box 700, New Ellenton, SC 29809, USA H. SCOTT RAY, USDA Forest Service, Savannah River, P.O. Box 700, New Ellenton, SC 20809, USA MARK VUKOVICH, USDA Forest Service, Southern Research Station, P.O. Box 700, New Ellenton, SC 29809, USA MATTHEW J. GOODE, USDA Forest Service, Southern Research Station, P.O. Box 700, New Ellenton, SC 29809, USA CHARLES RUTH, South Carolina Department of Natural Resources, 1000 Assembly St., Columbia,

The Problem Declining deer population at the United States Department of Energy’s Savannah River Site (SRS), South Carolina 2006-2009 Causes of decline: Coyotes? Bobcats? Disease? Malnutrition/change in habitat quality? Competition with other animals? Hunting?

Coyotes Recent addition to fauna population in the eastern United States (1978) SRS (1986) Numbers established (mid-1990s) Deer population declining in coincident of coyote population increase

Objective “…to quantify neonate survival rates and identify causes of mortality to directly evaluate whether coyotes may be responsible for declining recruitment in a South Carolina deer population.”

Adult Female Capture & Handling Tranquilizer: Telazol 250mg Xylazine hydroxide 150mg 1cc transmitter darts Reversal (80 min post injection): Tolazoline hydrochloride 160- 180mg Continue monitoring until recovery

Vaginal Implant Transmitter Does confirmed pregnant by ultrasound VIT inserted (Bowman and Jackson 1998 and Cartensen et al. 2003) Temp fell below 34.58ₒC ± 1ₒ Pulse rate changed from 40-80 PPM VIT fell out Tracked and found fawns

Neonate Capture & Handling Expelled VIT detected 3-hr time period for grooming and bonding with female Sometimes took 3-5 days to find neonate (weight approximate birth mass) Blindfolded, collared, released (avg. 6 min.) Transmitters did not affect neonate survival (J.C. Kilgo)

Neonate Monitoring 8 hrs until 4 wks old 1 to 2 times daily until 12 weeks old Weekly until 16 weeks old 91 neonates collared

Cause of Death Reached carcass upon death signal in 4-13 hours Puncture would in head/neck = coyote or bobcat Covered with mineral soil = coyote Far from kill site/whole carcass consumption/not cached = coyote (Harrison and Gilbert 1985) Covered with liter or sticks = bobcat Close to kill site = bobcat (Beale and Smith 1973) Tracks, scat, etc. DNA testing from swab samples (Wildlife Genetics International (WGI; Nelson, Canada)

Cause of Death Cont. Predation: 31 to 63/ 70 neonates that died (Table 3)

Other Causes Emaciation/marking-induced abandonment Hunting not conducive to this study because neonates reached recruitment age at 16 wks (can now be hunted (antlerless)) Harvest percentage 36%; 385 deer/yr; (1965-1999) 0.5 deer/km2 VS. 0.8-1.5 coyotes/km2

Results 67 VITs monitored (50 successful captures) 74 neonates (24 sets of twins) Located others (91 neonates total) 70/91 died Field methods (at least 50 predation) DNA (37/41 predation; 35/37 coyote) Coyote predation at least 26 (37%) to 56 (80%) Bobcats 7-9% Previous studies had smaller predation rates (Heugel et al. 1985 etc.)

Results Cont. 22 coyotes preyed upon 24 neonates Survival estimate 22.2% 32% harvested by hunters (Kilgo et al. 2010) Numbers cannot keep up Management: 636 deer harvested 1990-2004 161 2005-2008 (75% reduction helps with 77% mortality in neonates) Neonate mortality rate lower before coyote population increased (Dapson et al. 1979)

Survival Rate Survival rate: 0.230 (95% CI = 0.155-0.328) Best-fit model: 0.220 (95% CI = 0.144-0.320) Exclude emaciated 0.247 Only 0.017 greater Increased substantially after week 1 Near 1.000 around week 10 No mortalities after week 9 39% of deaths occurred during first week of life

Discussion Coyote predation main cause of death in neonates 9 weeks and younger Coyote predation affects recruitment at SRS Further study needed on carrying capacity of location for adaptive management plan