Seasonal Variation in Sexual Size Dimorphism in the Wrinkle-lipped Free-tailed Bat (Chaerephon plicatus Buchannan, 1800) Population in the Khao Chong Phran Non-hunting Area, Thailand Page 50-57; DOI: 10.32526/ennrj.17.3.2019.22

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Nutthakarn Boonpha Prateep Duengkae Supaporn Wacharapluesadee Chumphon Kaewket


The Khao Chong Phran Non-hunting Area has the largest population of wrinkle-lipped free-tailed bats (Chaerephon plicatus) in Thailand. We examined monthly variations in sexual size dimorphism through measurements of forearm length and body mass during 2016. Bats were captured in each month at dawn and dusk. Individuals were sexed, aged, measured and marked before release. During the year, we caught 1,715 individuals. Of these, we used only adult, non-pregnant individuals (405 males and 538 females) for our analysis. Males had significantly larger forearm lengths and body masses than females. The body masses of both sexes peaked at the beginning and end of the rainy season, and bats captured at dawn were heavier than those netted at dusk. Seasonal fluctuations in body mass were correlated with monthly variation in rainfall; the positive correlation is likely explained by the greater insect abundance during wet months. The climate in western Thailand is expected to become warmer and drier, with likely negative effects on populations of this species due to reductions in insect food resources. Maintenance of this large population of C. plicatus in the study area will depend on concerted conservation efforts and further research focused on population dynamics, prey availability and foraging habitats.


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How to Cite
Boonpha, N., Duengkae, P., Wacharapluesadee, S., & Kaewket, C. (2019). Seasonal Variation in Sexual Size Dimorphism in the Wrinkle-lipped Free-tailed Bat (Chaerephon plicatus Buchannan, 1800) Population in the Khao Chong Phran Non-hunting Area, Thailand. Environment and Natural Resources Journal, 17(3), Page 50-57; DOI: 10.32526/ennrj.17.3.2019.22. Retrieved from
Original Research Articles


1. Barclay RMR. Population structure of temperate zone insectivorous bats in relation to foraging behaviour and energy demand. Journal of Animal Ecology 1991;60(1):165-78.

2. Boonkerd K, Wanghongsa S. Management of bat caves. In: Pimmanrojakul W, editor. Annual Report of Wildlife Research Division. Bangkok: Royal Forest Department; 2002. p. 33-45 (in Thai).

3. Climatological Center. Changes in temperature and rainfall over Thailand under climate change [Internet]. 2016 [cited 2018 Aug 4]. Avialable from: (in Thai).

4. Csorba G, Bumrungsri S, Francis C, Bates P, Ong P, Gumal M, Kingston T, Heaney L, Balete D, Molur S. Chaerephon plicatus [Internet]. 2017 [cited 2017 Mar 3]. Available from: /4316/0.

5. Cumming GS, Bernard RTF. Rainfall, food abundance and timing of parturition in African bats. Oecologia 1997;111(3):309-17.

6. Dalhoumi R, Aissa P, Aulagnier S. Seasonal variations of sexual size dimorphism in two Mediterranean bat species from Tunisia: the Kuhl's pipistrelle (Pipistrellus kuhlii) and the Isabelline serotine (Eptesicus isabellinus). Folia Zoologica 2016;65(2):157-63.

7. Camargo NFD, Oliveira HFD. Sexual dimorphism in Sturnira lilium (Chiroptera, Phyllostomidae): can pregnancy and pup carrying be responsible for differences in wing shape? PLoS One 2012; 7(11):e49734.

8. Encarnação JA, Dietz M, Kierdorf U, Wolters V. Body mass changes in male Daubenton's bats Myotis daubentonii (Chiroptera, Vespertilionidae) during the seasonal activity period. Mammalia 2004;68(4):291-7.

9. Fleming TH, Hooper ET, Wilson DE. Three Central American bat communitis: structure, reproductive cycles, and movement patterns. Ecology 1972;53(4): 555-69.

10. Furey N, Racey P, Ith S, Touch V, Cappelle J. Reproductive ecology of wrinkle-lipped free-tailed bats Chaerephon plicatus (Buchannan, 1800) in relation to guano production in Cambodia. Diversity 2018;10(3):91-100.

11. Gager Y, Tarland E, Lieckfeldt D, Ménage M, Botero-Castro F, Rossiter SJ, Kraus RH, Ludwig A, Dechmann DK. The value of molecular vs. morphometric and acoustic information for species identification using sympatric molossid bats. PLoS One 2016;11(3):e0150780.

12. Goodman SM, Rajemison FI, Olivà S. Morphometric patterns of secondary sexual dimorphism and seasonal differences in Rousettus madagascariensis from northern madagascar. Acta Chiropterologica 2017; 19(1):71-5.

13. Happold D, Happold M. Reproduction of Angola free-tailed bats (Tadarida condylura) and little free-tailed bats (Tadarida pumila) in Malawi (Central Africa) and elswhere in Africa. Journal of Rreproduction and Fertility 1989;85:133-49.

14. Herron JC, Freeman S. Evolutionary Analysis. 5th ed. England: Pearson Education Limited; 2015.

15. Hillman A. The study of Wrinkled-lipped bats (Tadarida plicata) at Khao Chong Phran, Ratchaburi. Journal of Thai Forestry Research 1999;1(1):72-83.

16. Hillman A. Monitoring of Tadarida plicata at Khao Chong Phran Non-hunting Area, Ratchaburi. Journal of Wildlife in Thailand 2006;13(1):31-42.

17. Hurtado N, Sepúlveda RD, Pacheco V. Sexual size dimorphism of a sensory structure in a monomorphic bat. Acta Chiropterologica 2015;17(1):75-83.

18. Keeley AT, Keeley BW. The mating system of Tadarida brasiliensis (Chiroptera: Molossidae) in a large highway bridge colony. Journal of Mammalogy 2004;85(1):113-9.

19. Krutzsch PH, Crichton EG. Observations on the reproductive cycle of female Molossus fortis (Chiroptera: Molossidae) in Puerto Rico. Journal of Zoology 1985;207(1):137-50.

20. Kunz TH, Wrazen JA, Burnett CD. Changes in body mass and fat reserves in prehibernating little brown bats (Myotis lucifugus). Ecoscience 1998;5(1):8-17.

21. Kunz TH, Torrez BE, Bauer D, Lobova T, Fleming TH. Ecosystem services provided by bats. Annals of the New York Academy of Sciences 2011;1223(1):1-38.

22. Leelapaibul W. The Diet and Feeding Factors of the Wrinkle-lipped Free-tailed Bat (Tadarida plicata) at Khao-Chong-Pran, Ratchaburi Province [dissertation]. Bangkok, Thailand: Kasetsart University; 2003 (in Thai).

23. Leelapaibul W, Bumrungsri S, Pattanawiboon A. Diet of wrinkle-lipped free-tailed bat (Tadarida plicata Buchannan, 1800) in central Thailand: insectivorous bats potentially act as biological pest control agents. Acta Chiropterologica 2005;7(1):111-9.

24. Lisón F, Haz Á, Carlos GR, Calvo JF. Sexual size dimorphism in greater mouse-eared bat Myotis myotis (Chiroptera: Vespertilionidae) from a Mediterranean region. Acta Zoologica 2014;95(2):137-43.

25. McCracken GF, Wilkinson GS. Bat mating systems. In: Crichton EG, Krutzch PH, editors. Reproductive Biology of Bats. Cambridge: Great Britain at the University Press; 2000. p. 321-62.

26. McPherson FJ, Chenoweth PJ. Mammalian sexual dimorphism. Animal Reproduction Science 2012; 131(3-4):109-22.

27. Nolte MJ, Hockman D, Cretekos CJ, Behringer RR, Rasweiler JJ. Embryonic staging system for the Black Mastiff Bat, Molossus rufus (Molossidae), correlated with structure-function relationships in the adult. Anat Rec (Hoboken) 2009;292(2):155-68.

28. Nurul‐Ain E, Rosli H, Kingston T. Resource availability and roosting ecology shape reproductive phenology of rain forest insectivorous bats. Biotropica 2017;49(3): 382-94.

29. Oxberry BA. Female reproductive patterns in hibernating bats. Journal of Reproduction and Fertility 1979; 56(1):359-67.

30. Racey P. Reproductive assessment of bats. In: Kunz TH, Parsons S, editors. Ecological and Behavioural Methods in the Study ofB. Maryland: Johns Hopkins University Press; 2009. p. 249-64.

31. Ralls k. Mammals in which females are larger than males. The Quarterly Review of Biology 1976;51(2):245-76.

32. Ratrimomanarivo FH, Goodman SM, Stanley WT, Naidoo T, Taylor PJ, Lamb J. Geographic and phylogeographic variation in Chaerephon leucogaster (Chiroptera: Molossidae) of Madagascar and the western Indian Ocean islands of Mayotte and Pemba. Acta Chiropterologica 2009;11(1):25-52.

33. Rex K, Kelm DH, Wiesner K, Kunz TH, Voigt CC. Species richness and structure of three Neotropical bat assemblages. Biological Journal of the Linnean Society 2008;94(3):617-29.

34. Srilopan S, Bumrungsri S, Jantarit S. The wrinkle-lipped free-tailed bat (Chaerephon plicatus Buchannan, 1800) feeds mainly on brown planthoppers in rice fields of central Thailand. Acta Chiropterologica 2018;20(1):207-19.

35. Stevens RD, Platt RN. Patterns of secondary sexual size dimorphism in New World Myotis and a test of Rensch’s rule. Journal of Mammalogy 2015;96(6): 1128-34.

36. The R Development Core Team. R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing: Reference Index [Internet]. 2017 [cited 2017 Mar 6]. Available from:

37. Utthammachai K. Foraging Habitat Use by Acoustic Monitoring of Tadarida plicata (Buchannan, 1800) in an Agricultural Landscape, Ratchaburi Province [dissertation]. Bangkok, Thailand: Kasetsart University; 2009.

38. Utthammachai K, Bumrungsri S, Chimchome V, Russ J, Mackie I. Habitat use and feeding activity of Tadarida plicata in Thailand. Thai Journal of Forestry 2008;27(2):21-7.

39. Vivier L, Merwe MVD. Reproduction in the female Angolan free‐tailed bat, Tadarida (Mops) condylura (Microchiroptera: Molossidae), in the eastern Transvaal, South Africa. Journal of Zoology 1997; 243(3):507-21.

40. Voigt CC, Holderied MW. High manoeuvring costs force narrow-winged molossid bats to forage in open space. Journal of Comparative Physiology B 2012;182(3): 415-24.

41. Wanghongsa S, Boonkerd K. Behaviour of bats (Tadarida Plicata) in Chao Ram cave, Sukhothai province, Thailand. Journal of Wildlife in Thailand 2000;8(1): 42-9 (in Thai).

42. Weckerly FW. Sexual-size dimorphism influence of mass and mating systems in the most dimorphic mammals. Journal of Mammalogy 1998;79(1):33-52.

43. Wu H, Jiang T, Huang X, Lin H, Wang H, Wang L, Niu H, Feng J. A test of Rensch's rule in greater horseshoe bat (Rhinolophus ferrumequinum) with female-biased sexual size dimorphism. PLoS One 2014;9(1):e86085.