92 Zoological Studies 46(1): 92-102 (2007) 92 In Taiwan, shark catch statistics are catego- rized into (1) large pelagic sharks and (2) small demersal sharks in the Fisheries Statistics Yearbook Taiwan. Annual yields of small sharks in Taiwan declined dramatically from 5699 tn in 1993 to 1176 tn in 2003, which implied that these stocks, mainly caught by trawlers and longliners in coastal waters off Taiwan, have experienced heavy exploitation in recent years. Huang (1996) mentioned that the spotted shark, Mustelus manazo, once a very common species, had almost com- pletely disappeared from central and southwestern Taiwanese waters. Chen et al. (1996) also described severe declines in several demersal shark species such as the sawfish, Anoxypristis cuspidata, and members of the Centrophoridae. Fisheries-related biological information, essential for fisheries management, is urgently needed to ensure sustainable utilization of demersal shark stocks. The whitespotted bamboo shark, Chiloscyl- lium plagiosum, is a small, demersal species that inhabits tropical and subtropical coastal waters of the Indo-Pacific region. This species is broadly distributed off Madagascar, India, Sri Lanka, Thailand, Indonesia, Vietnam, Malaysia, Singapore, the Philippines, China, Taiwan, and Japan (Compagno 2001). However, very little is known about its stock structure. In Taiwan, this species is found in the coastal waters of western Age and Growth Estimates of the Whitespotted Bamboo Shark, Chiloscyllium plagiosum, in the Northern Waters of Taiwan Wei-Ke Chen 1 , Po-Chuan Chen 2 , Kwang-Ming Liu 2, *, and Shyh-Bin Wang 2 1 Department of Environmental Biology and Fisheries Science, Notional Taiwan Ocean University, 2 Pei-Ning Road, Keelung 202, Taiwan 2 Institute of Marine Resource Management, National Taiwan Ocean University, 2 Pei-Ning Road, Keelung 202, Taiwan (Accepted March 20, 2006) Wei-Ke Chen, Po-Chuan Chen, Kwang-Ming Liu, and Shyh-Bin Wang (2007) Age and growth estimates of the whitespotted bamboo shark, Chiloscyllium plagiosum, in the northern waters of Taiwan. Zoological Studies 46(1): 92-102. Age and growth rates of the whitespotted bamboo shark, Chiloscyllium plagiosum, were described from 481 specimens (313 females and 168 males, 35.5-85.0 cm in total length) collected from Feb. 2002 to Feb. 2003 in waters off northern Taiwan on bottom longlines or lobster trap nets. The sex-specific rela- tionships between weight (W) and total length (TL) significantly differed and could be expressed as: W = 1.64 x 10 -3 TL 3.15 (n = 313, p < 0.05) for females and W = 5.09 x 10 -3 TL 2.87 (n = 168, p < 0.05) for males. Age was determined using vertebral banding patterns. A single growth band (comprising translucent and opaque zones) is formed each year, with up to 7 bands observed for both sexes. A marginal increment ratio analysis indicated that the translucent zone formed from June to Sept. Four growth functions, the traditional von Bertalanffy (VBGF), VBGF with a fixed size-at-birth (L 0 ), Gompertz, and Robertson functions were used to model the observed length-at-age data. The sex-specific growth equations significantly differed. The traditional VBGF, based on observed length-at-age data, predicted an asymptotic length (L ∞ ) of 95.9 cm TL, a growth coefficient (k) of 0.205, a theoretical age at zero length (t 0 ) of -0.95 yr for females; and an L ∞ of 100.9 cm TL, k of 0.198, t 0 of -0.90 yr for males. The parameters of VBGF with L 0 set to 15.0 cm were estimated to be an of L ∞ 93.2 cm TL and k of 0.224 for females; and an of L ∞ 98.5 cm TL and k of 0.212 for males. Akaike , s information criterion showed that the VBGF with L 0 had the best fit. Ages at maturity estimated from the VBGF with L 0 were 4.5 and 4.4 yr for females and males, respectively. http://zoolstud.sinica.edu.tw/Journals/46.1/92.pdf Key words: Age and growth, Chiloscyllium plagiosum, von Bertalanffy growth equation, Northern Taiwan. *To whom correspondence and reprint requests should be addressed. Tel: 886-2-24622192 ext. 5018. Fax: 886-2-24620291. E-mail:kmliu@mail.ntou.edu.tw