1. WILD PIG REPRODUCTION IN LOUISIANA …… JUST THE FACTS Kim Marie Tolson, ULM James M. LaCour, LDWF

2. Misconceptions in the Media

3. “Adult sows can produce three litters a year.”

4. Misconceptions in the Media “Adult sows can produce three litters a year.” “one female can have 300 piglets in two years”

5. BIOLOGY OF WILD PIGS Habitat generalists Low natural mortality Opportunistic omnivores High reproductive potential

6. BIOLOGY OF WILD PIGS Habitat generalists Low natural mortality Opportunistic omnivores High reproductive potential

7. BIOLOGY OF WILD PIGS Habitat generalists Low natural mortality Opportunistic omnivores High reproductive potential

8. BIOLOGY OF WILD PIGS Habitat generalists Low natural mortality Opportunistic omnivores High reproductive potential

9. BIOLOGY OF WILD PIGS Habitat generalists Low natural mortality Opportunistic omnivores High reproductive potential

10. Wild Pig Breeding Biology Early reproductive maturity Gestation period ~114 days – 3 months, 3 weeks, 3 days – potential multiple litters/yr Capability to produce large litters HIGH REPRODUCTIVE POTENTIAL!!

11. OBJECTIVES Characterize the breeding biology of wild pigs in Louisiana – Determine average litter size – Calculate reproductive efficiency – Determine peak breeding dates – Compare data with other populations of feral hogs

12. METHODS Collection May 2010 to June 2011 Reproductive tracts removed: ovaries & uterus - Collection Date - Location (Parish) - Weight - Notes - Tracts frozen

13. METHODS OVARIES – Preserved in 10% buffered formalin – Sliced in 1-2 mm sections – Presence/number of follicles or corpora lutea (CL) Ovary with follicles Ovary with CL Photos courtesy Meg O’Boyle

14. METHODS UTERI – Number and gender of fetuses – Crown-rump measurements (avg. for litter) – Extrapolate breeding and farrowing dates (Henry 1968)

15. RESULTS 87 Reproductive Tracts – 80 Adults + 7 Sub-adults – 47 lb. sow with follicular development

16. RESULTS 87 Reproductive Tracts – 80 Adults + 7 Sub-adults – 47 lb. sow with follicular development

17. RESULTS 35 Pregnant 43.75% 40 Developing follicles50.00% 2 CL in ovaries 2.50% 3 No repro activity 3.75% 80 Adult sows (77/80 showed repro activity in ovaries)

18. RESULTS 35 Pregnant 43.75% 40 Developing follicles50.00% 2 CL in ovaries 2.50% 3 No repro activity 3.75% 80 Adult sows (77/80 showed repro activity in ovaries)

19. RESULTS CLFetuses RE*__ Sum229 176 76.85% ---------------------------------------------------------------- Mean6.54 5.03 ---------------------------------------------------------------- Range (4-10) (2-10) ---------------------------------------------------------------- *RE = (# fetuses / # CL) x 100

20. COMPARISON OF LITTER SIZE _____________________________________________________________________________________________ Locationn Mean # of fetuses (range)Reference_____________ Louisiana355.03 (2-10)Tolson and LaCour (2013) Georgia 176.20 (?-9)Hagen and Kephart (1980) (penned) Georgia355.89 (3-11)Jolley (2007) (free ranging) South Carolina 87.40 (5-12)Sweeney et al. (1979) Tennessee204.65Henry (1968) Texas645.40 (2-11)Delgado-Acevedo et al. (2010) (southern and central counties) Texas216.30Taylor et al. (1998) -South Texas Plains (western) Texas185.60Taylor et al. (1998) -Gulf Coast Prairie (eastern) New Zealand2916.20 (1-11)Dzieciolowski et al. (1992) Spain523.58 (1-7)Fernandez-Llario and Mateos- Quesada (1998)__________

21. Conception Dates

22. Farrowing Dates

23. Breeding Biology of Wild Pigs in Louisiana Average litter size is 5-6 Conception and farrowing occurs year round Two peaks in conception: – Broad peak from Sept. through Dec. – Narrow peak in Feb. – Mar. Results not unexpected – parallels other hog populations across the south.

24. Reproductive Potential Age of Reproductive Maturity – around 6 months – 47 pounds! Number of Litters per Year – Commonly reported = 2/12 mos. – Actually = 2/15-18 mos. Number of offspring per Litter – Average = 5 to 6 Wildpiginfo.msstate.edu www.flickr.com

25. Reproductive Potential Comparison of Large Mammals White-tail Deer Wild Pig Reproductive maturity Avg. # offspring Frequency of breeding

26. Reproductive Potential Comparison of Large Mammals White-tail Deer Wild Pig Reproductive18 mo. ~ 6 mo. maturity Avg. # offspring Frequency of breeding

27. Reproductive Potential Comparison of Large Mammals White-tail Deer Wild Pig Reproductive18 mo. ~ 6 mo. maturity Avg. # offspring 1.5 5-6 Frequency of breeding

28. Reproductive Potential Comparison of Large Mammals White-tail Deer Wild Pig Reproductive18 mo. ~ 6 mo. maturity Avg. # offspring 1.5 5-6 Frequency of breeding 1/12 mo.1/8-9 mo.

29. REPRODUCTIVE FACTS Both sexes can live 10-14 yrs (avg. is 4-8 yrs) No reproductive senescence has been noted Litters can be sired by more than 1 male Males produce viable sperm year round Synchronous estrous by females in a sounder

30. REPRODUCTIVE FACTS Both sexes can live 10-14 yrs (avg. is 4-8 yrs) No reproductive senescence has been noted Litters can be sired by more than 1 male Males produce viable sperm year round Synchronous estrous by females in a sounder

31. REPRODUCTIVE FACTS Both sexes can live 10-14 yrs (avg. is 4-8 yrs) No reproductive senescence has been noted Litters can be sired by more than 1 male Males produce viable sperm year round Synchronous estrous by females in a sounder

32. REPRODUCTIVE FACTS Both sexes can live 10-14 yrs (avg. is 4-8 yrs) No reproductive senescence has been noted Litters can be sired by more than 1 male Males produce viable sperm year round Synchronous estrous by females in a sounder

33. REPRODUCTIVE FACTS FEMALES: – Lactation may inhibit estrous for up to 2 months – May experience anestrous period in hot/dry mos. – Anestrous also reported in years of mast failure – Food resources can influence reproduction

34. REPRODUCTIVE FACTS FEMALES: – Lactation may inhibit estrous for up to 2 months – May experience anestrous period in hot/dry mos. – Anestrous also reported in years of mast failure – Food resources can influence reproduction

35. REPRODUCTIVE FACTS FEMALES: – Lactation may inhibit estrous for up to 2 months – May experience anestrous period in hot/dry mos. – Anestrous also reported in years of mast failure – Food resources can influence reproduction

36. REPRODUCTIVE FACTS FEMALES: – Lactation may inhibit estrous for up to 2 months – May experience anestrous period in hot/dry mos. – Anestrous also reported in years of mast failure – Food resources can influence reproduction

37. CONCLUSIONS Wild pigs may not be as prolific as they are often made out to be in the media

38. CONCLUSIONS Wild pigs may not be as prolific as they are often made out to be in the media BUT, their reproductive potential is greater than native large mammals

39. CONCLUSIONS Wild pigs may not be as prolific as they are often made out to be in the media BUT, their reproductive potential is greater than native large mammals

40. CONCLUSIONS Wild pigs may not be as prolific as they are often made out to be in the media BUT, their reproductive potential is greater than native large mammals

41. ACKNOWLEDGEMENTS Dr. James LaCour Meghan O’Boyle ULM Biology graduate students USDA/APHIS-Wildlife Services personnel LDWF personnel USFWS personnel at Lake Ophelia NWR and Upper Ouachita NWR Barksdale AFB personnel

42. QUESTIONS? http://www.iheartbacon.com/category/bacon-reviews/ tolson@ulm.edu