!l1jjldi(fj. Z({))([))}([j)gi((J!ffj} Reproduction and Diet of the Brown Frog Rana longicrus in Taiwan

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1 Zlgical Studies 34(3): (199) Z({))([))}([j)gi((J!ffj}!l1JJldi(fJ Reprductin and Diet f the Brwn Frg Rana lngicrus in Taiwan Yeng-Chy Karn':', Chin-Shian Wang 2 and Ya-Sung Lin 2 'Depenmen: f Bilgy, Natinal Changhua University f Educatin, Paisa Village, Changhua, Taiwan 00, R.O.C. epartment f Zlgy, Natinal Taiwan University, Taipei, Taiwan 106, R.O.C. (Accepted May 31, 199) Yeng-Chy Kam, Chin-Shian Wang and Ya-Sung Lin (199) Reprductin and diet f the brwn frg Rana lngicrus in Taiwan. Zlgical Studies 34(3): The natural histry f the brwn frg Rana lngicrus was studied fr twelve mnths in the Ati area, nrthern Taiwan. Rana lngicrus is a diurnal, terrestrial species that lives mainly in hill areas during the nn-breeding seasn. Hwever, during the breeding seasn, frgs mve t lwland areas, particularly ricefields, t breed. Adult females are larger than males. Reprductive data frm males and females suggest that the breeding seasn is frm Nvember t March. Frglets were abundant in March, and they reach adult sizes by September. Desiccatin and disturbances frm human activities were the leading causes f tadple mrtality. Diets cnsisted f invertebrates f the classes Gastrpda, Oliqchaeta Arachnida, Crustacea, Insecta, and Chilpda. Seasnal, sexual, and ntgenetic differences in stmach cntents were described. Key wrds: Amphibian, Diet, Reprductin. Little infrmatin is available n the bilgy f the brwn frg Rana lngicrus. Current knwledge f this species is limited mstly t systematics and distributin (Ppe 1931, Yuan 190, Liu and Hu 1961, Kuramt 1974, Lue 1990). R. Lngicrus is currently fund n the island f Taiwan and in Fujian Prvince (Zha and Adler 1993). R. lngicrus and Rana japnica are s similar in size and shape that Ppe (1931) and Liu and Hu (1961) placed R. lngicrus in the synnymy f R. japnica. Hwever, Kuramt (1974) cncluded frm hybridizatin experiments that R. lngicrus is a valid species. A similar cnclusin was als made by Yuan (190) wh studied the develpment f tadples and the mrphlgy f adults. R. lngicrus is a lwland species mainly distributed in the nrthern part f the island f Taiwan (Lue 1990). Yuan (190) has briefly described mrphlgical characters f adults, tadples, and eggs f R. lngicrus and als he has reprted that these frgs breed during the cldest mnths; hwever, detailed infrmatin n reprductin has nt been available. In fact, f the twelve ranids fund in Taiwan, nly R. lngicrus breeds slely in the winter (Lue 1990, pers. bs.). Why R. lngicrus breeds nly during winter is an eclgical and physilgical puzzle. A cld envirnment pses a severe threat t the frgs, particularly with respect t the develpment and grwth f embrys and tadples. Because amphibians are pikiltherms, cld temperatures depress the metablism, grwth, and develpment f embrys and tadples. A further drp f temperature, which exceeds the thermal tlerance f embrys r tadples, will cause mrtality. Anther imprtant factr is that cld temperatures inhibit the metamrphic prcess; thus, tadples may cntinue t grw but are unable t metamrphse (Ddd and Ddd 1976). Thus, a full understanding f the bilgy f R. lngicrus is needed t shed light n hw this species adapts t its envirnment. In this study, we examined the natural histry f R. lngicrus, including its reprductive bilgy, mrphlgy, and diet. This is part f a prject *T whm all crrespndence and reprint requests shuld be addressed. 193

194 Zlgical Studies 34(3): 193-1 (199) designed t understand the reprductive physilgy and eclgy f anurans fund in Taiwan. 1 '2 :S 14 "0.Q Q; 13 c, 0 12 s: a.

2 194 Zlgical Studies 34(3): (199) designed t understand the reprductive physilgy and eclgy f anurans fund in Taiwan. 1 '2 :S 14 "0.Q Q; 13 c, 0 12 s: a.. MATERIALS AND METHODS The study site is lcated in the Ati area (apprximately 2 00'40" N, 121 0'40" E) which is characterized by lw terrain, with hills n mre than 300 m in height, and a lwland area principally used fr grwing rice. The hillsides are mainly cvered with primary and secndary frests. Fur majr vegetatin cmmunities were recgnized in the hill regins: bamb, Pinus, Acacia, and primary bradleaf frests. The dminant species f the primary frests include Psychtria rubra, G/chidian rubrum, and Persea thunbergii. Climate in the Ati area (Fig. 1) (prvided by the Central Weather Bureau) is similar t that in much f western Taiwan with the exceptin f the precipitatin pattern (Alexander et al. 1979, Lin 1979). Air temperatures and phtperid reached their maximums in August and June, and drpped t their minimum values in January and December, respectively. Hwever, there were tw majr rainy seasns. Frm May t September was the first rainy seasn in which mst rains were assciated with typhns and shuthwest mnsns (Alexander et al. 1979). Frm Nvember t December was the secnd rainy seasn in which mst rains were E E- ""iii a. C 400 ci.. 'iii a: E I- a 10 J FMAMJJ ASOND Mnth Fig. 1. Phtperid, temperature (empty circles), and rainfall (slid circles) fr the Ati area. prbably caused by gusty nrtheast mnsns and cld frnts. Frgs were cllected biweekly alng a transect line between hurs frm January 1981 t December This transect line, abut 3 km lng, passed thrugh all majr habitats, including ricefields, creeks, marshes, pen areas and wds (primary and secndary frests). Frgs were killed and preserved in 10% frmalin sn after capture. The snut-vent length (SVL) and bdy mass f sme frgs were measured befre they were killed. Autpsies were then perfrmed in the labratry: the testes in lng axis (males) and va and viducts (females) were remved and measured. Grss varian mrphlgy was recrded t mnitr the reprductive status f females. The methd develped by Alexander et al. (1979) was mdified fr this study. Briefly, a ttal f five reprductive classes were recgnized: classes 1-3 represent nn-reprductive stages, while classes 4- represent reprductive stages. Class 1 was characterized by clear and clrless varies. Ocytes were small, n mre than abut 0.4 mm in diameter. Oviducts were hardly visible t the naked eye. Class 2 was characterized by yellwish varies. The largest cytes were abut mm in diameter and were begining t accumulate pigment. Oviduct diameter was n mre than 0.7 mm. Class 3 was characterized by unifrmly dark varies. The largest cytes were abut mm in diameter and pigmented withut distinct vegetal hemispheres. Oviduct diameter was abut mm. Class 4 was characterized by dark varies. Ocytes diameters were mm and many had distinct vegetal hemispheres. Oviduct diameter was abut mm. Class was characterized by bright varies. Ocytes were wellplarized with diameters greater than 1.3 mm. Oviduct diameter was greater than 1.47 mm. Fr dietary analyses, the stmachs were pened, and the cntents were carefully remved and identified t a reliable taxnmic level. Mst fd items were identified t class but insects were further identified t rders. The prprtin f each fd item and the percent f frgs cntaining the items were calculated (Vitt and Ohmart 197). The degree f dietary verlap was derived frm stmach cntents using the fllwing equatin: D = [ Sum!PxrPy,i1J x 100 where D is the percent f verlap and Px,i and Py,i are the prprtins f the number f items

3 Kam et al. - Natural Histry f Brwn Frgs 19 individuals (r grups) x and y utilized in resurce categry i (Schener 1970, Rathcke 1976). Dietary verlap was cmpared between (a) males and females, (b) juveniles and adults, (c) seasns, and (d) habitats. Prey items between grups were statistically cmpared using a G test (Skal and Rhlf 1980). Data were analyzed by a SAS prgram (SAS Institute Inc. 1988), and a significant difference was declared when p < 0.0 r less. RESULTS AND DISCUSSION Size and mrphlgy R. lngicrus shwed sexual dimrphism in that the SVL f females (41.76 ± 4.60 mm, mean ± SD, n = 119) was significantly greater than that f males (38.22 ± 2.1 mm, n = 3, t = 3.69, P < 0.001) (Fig. 2). Females attained SVL as large as mm and weighed 13.3 g, but the largest SVL f a male measured nly 42.8 mm with a bdy weight f. g. The smallest gravid female measured 32.2 mm SVL and weighed 2.32 g, while the smallest sexually mature male (judqed by the welldevelped nuptial pad) measured 33.0 mm SVL. Bdy size and weight were well crrelated in males and females (r = 0.9, n = 71, P < 0.01). Reprductin R. lngicrus is a diurnal terrestrial species and can be fund in lwland and hill regins. During the breeding seasn, frgs migrated t rice fields in the lwlands and aggregated in particular sites t breed. Breeding activities were prbably initiated by heavy rains. N eggs r tadples were fund in the hill regins where streams, creeks, and a permanent marsh were available, which suggests that R. lngicrus breeds nly in the lwland regins, particulary, in ricefields. The reprductive status f male frgs can be assessed frm the presence f a nuptial pad and vcal sac and frm testes mrphlgy. Nupital pads and vcal sacs, which are majr secndary characteristics, were used as indicatr f reprductive status in R. rugulsa (Ka et al. 1994). Nupital pads, enlarged testes, and cnvluted epididymides were bserved in all male frgs frm Octber t March suggesting that the breeding seasn fr males extended at least frm Octber t March. Als, males reached sexual maturity within the first year. The smallest male cllected during the breeding seasn was 33 mm in SVL and had enlarged testes and cnvluted epidydymides. The varian mrphlgy f female frgs is summarized in Fig. 4. Vitellgenesis began in September, mst females became gravid in December, indicating that the breeding peak was in December, and all females reprduced synchrnusly (Fig. 4). Mst likely, nly ne clutch per feamle was prduced in each breeding seasn. Ova were smallest in August and were largest in 2 4 female 12 7 [!j male en 13 OJ 3 e LL 1 E '0 -S 6 Qj Qj.0 E 10 E ~ al z 0 en.~ - f SVL (mm) Fig. 2. Size (SVL) distributin f female and male Rana lngicrus. J F M A M J J A SON 0 Mnth Fig. 3. Mnthly changes (mean values ± SE) in testis diameter f Rana lngicrus. Sample size is indicated by numbers.

4 196 Zlgical Studies 34(3): (199) December (0.4 ± 0.06 mm and 1.3 ± 0.17 mm, respectively; t = 12.1, P < 0.001). Seasnal changes f male and female reprductive rgans and accessry rgans shw that the reprductin f R. lngicrus is cyclic. The reprductive mde f R. lngicrus belngs t the mst primitive type f breeding, accrding t the classificatin f reprductive mdes by Duellman and Trueb (1986), i.e., mde 1: eggs are depsited in water, and eggs and feeding tadples are in lentic water. It is mst likely that the breeding seasn is frm Nvember t March with the breeding peak in December, but the exact timing can be influenced by precipitatin r human agricultural activities. Mst eggs were vipsited in water f ricefields prir t the cultivatin, and the water in the ricefield was either frm rainfall r irrigatin. Yuan (190) reprted that R. lngicrus fund in Mu-chan and Tsa-shan bred a mnth earlier than frgs fund in the ricefields near the campus f Natinal Taiwan University. He speculated that the delay in the breeding seasn was due t the shrtage f water in the ricefield which was caused by the delay f the rice harvest. A similar clse relatinship between anuran reprductin and human agricultural activities was als reprted fr Rana limncharis (Alexander et al. 1979). The thermal eclgy f R. lngicrus has nt been studied, thus, the physilgical effects f lw temperatures n the develpment f embrys and tadples are nt knwn. The duratin f develpment f R. lngicrus frm eggs after fertilizatin t newly metamrphsed adults is abut 0-60 days and it is cmparable t ther ranids (Yuan 190, Duellman and Trueb 1986). This suggests that develpment f embrys and tadples Jan. Feb. March n = 7 n = n = n = 8 ~ e O) OJ tiḻ C 0) 0 CD 100 n, July Aug. Sept. n = 8 n = n = Oct. Nv. n = 11 n = Ovarian Develpmental Stage Fig. 4. Prprtin f each varian develpmental stage in mnthly cllectins f female Rana lngicrus. Samples size is indicated by n.

5 Kam et al. - Natural Histry f Brwn Frgs 197 f this species is nt affected by lcal cld temperatures. Early studies n the thermal relatins f amphibians have shwn that individuals which breed in cld envirnments exhibit physilgical plasticities which allwed them t adapt well t thse envirnments. These adaptatins include a lw temperature tlerance, a high rate f develpment, and a high develpmental 0 10 at lw temperatures (Herreid and Kinney 1967, Bachmann 1969, Brwn , Duellman and Trueb 1986). Herreid and Kinney (1967) have shwn that eggs f Rana sylvatica had a survival rate f at least 0% when water temperature was 6-29 C, while the preferred temperature f tadples ranged frm 9 t 29 C. Anurans that breed in extreme nrthwestern Washingtn, U.S.A., had embrynic temperature tlerances f 4-21 C (Rana aurra), and 6-28 C (Hyla regilla) (Brwn ). Winter temperatures at Ati are nt that cld as the lwest mnthly temperature was abut 16 C in December. Thus, temperature may nt pse a severe threat t the eggs r embrys. Hwever, when a cld frnt mves in, ambient ~ Jan.-Feb.!:TIl Mar.-Apr. 10!:TIl May-June '0 Qi..0 E ::l Z!:TIl July-Aug. mj Sept.-Oct. mj Nv.-Dec SVL (mm) Fig.. Bimnthly size distributin f Rana lng/crus.

198 Zlgical Studies 34(3): 193 1 (199) temperatures have been recrded well belw 1O e. The duratin f cld shck may be shrt, yet critical t the develpment and grwth f embrys.

6 198 Zlgical Studies 34(3): (199) temperatures have been recrded well belw 1O e. The duratin f cld shck may be shrt, yet critical t the develpment and grwth f embrys. Thus, further studies are needed t reveal pssible mechanisms by which embrys and tadples survive in cld envirnments. What are the advantages f being a winter breeder? Aggregatins f frgs at a particular site during the breeding seasn attract predatrs, and a crrespnding high predatin rates. Hwever, less predatin can be expected fr winter breeders because many pikilthermic predatrs, such as snakes, may enter hibernatin. In additin, breeding in winter prvides a tempral partitining f breeding sites which reduces interspecific cmpetitin fr space and fd. Of the nine species f anurans fund in the Ati area, seven species are spring r summer breeders, and fur species (Rana Iimncharis, Hyla chinensis, But melanstictus, and Micrhyla rnata) use ricefields as their main vipsitin sites. Thus, seasnally heavy cmpetitin fr space and fd in bth adults and tadples is unavidable. In additin, increased densities als attract mre predatrs, resulting in even higher predatin rates. Tempral partitining f breeding sites is cmmn within tadple cmmunities (Heyer 1976, Seale 1980, Wiest 1982). Egg, embrynic, and tadple develpment Eggs were fertilized externally, and egg clutches with 600-2,000 eggs were then depsited int water. N parental care was bserved. Field bservatins shwed that tadples cntinued t grw and develp in water pls after hatching. The appearance f frglets in March suggests that this develpment tk abut tw mnths. Our field bservatins agree with an earlier study where the duratin f develpment frm an egg after fertilizatin t a newly metamrphsed frg let tk abut tw mnths under labratry cnditins (water temperature 19- C) and 0 days in the field (water temperature 19- C) (Yuan 190). Frglets were abundant in March, reaching adult size in September (Fig. ). Frgs cllected frm September t February had almst identical size distributins, indicating that frglets grew rapidly during spring and summer and reached adult size within ne year (Fig. ). During breeding seasn, the varies in mst f the cllected females cntained vitellgenic fllicles, indicating that R. lngicrus reaches sexual maturity within ne year. Tadple mrtality Eggs and tadples in the ephemeral flded ricefields befre plwing were subjected t heavy mrtality due t disturbance by human activities and by the desiccatin f habitats. Field bservatins have cnfirmed that the plwing f ricefields is the single mst imprtant cause f mrtality f eggs and tadples f R. lngicrus. Six weeks prir t plwing (frm 11/29/1981 t 1//1982), a ttal f 34 egg clutches were depsited at a particular site in a ricefield; hwever, all the eggs and tadples disappeared sn after plwing. It is believed that the turning ver f the sil simply buried all the eggs and tadples. Field bservatins als cnfirmed that desiccatin is anther majr cause f tadple mrtality in R. lngicrus. Ephemeral pnds in ricefields and depressins n dirt rads were favrite spts fr egg depsitin. Hwever, high evapratin during sunny days caused rapid drying f the Table 1. Summary f the diet f Rana lngicrus. Ttal number f stmachs examined was 148 Prey categry n % ttal % frequency" Mllusca Gastrpda Annelida Oligchaeta Arthrpda Crustacea Arachnida Chilpda Insecta Cleptera Hymenptera Orthptera Diptera Isptera Lepidptera Hmptera Hemiptera Dermaptera Cllembla Others Insect larvae TOTAL "Percent f frgs cntaining the item. bnumber f unknwn prey species = 42; number f stmachs with vegetatin and/r seeds = 27; number f empty stmachs = 23.

Kam et al. - Natural Histry f Brwn Frgs 199 water pls. On many ccasins, we fund thusand f tadples trapped in drying and chked water pls. N fish predatrs were bserved in these breeding pnds.

7 Kam et al. - Natural Histry f Brwn Frgs 199 water pls. On many ccasins, we fund thusand f tadples trapped in drying and chked water pls. N fish predatrs were bserved in these breeding pnds. Dietary analyses The diet f 148 individuals f R. lngicrus cnsisted primarily f invertebrates f the classes Gastrpda, Oligchaeta, Arachnida, Crustacea, > c :::J 0- u: -! Spring Summer Insecta (adults and larvae), and Chilpda (Table 1). Arachnids and larval and adult insects were the mst abundant items in their diets. Within class Insecta, the rders Hymenptera and Cleptera cmprised ver 8% f the ttal diet item. The family Frmicidae (ants) were particularly abundant within the rder Hymenptera, cnsisting f 86% f the diet item f this rder. Thirty-three f 148 frgs had empty stmachs, and half f these were cllected during the summer seasn. The stmachs f 27 frgs cntained detritus and sil particles. Seasnal differences in diet were apparent in R. lngicrus (Fig. 6, Table 2). During the winter seasn, frgs cnsumed mainly clepterans, spiders, and crustaceans. Frgs spent mre time in r near water, thus, a high frequency f crustaceans was expected (Fig. 6). Hwever, the diet shifted t ants and spiders in the spring. During summer and autumn, ants and insect larvae became the dminant diet items. Seasnal differences in diet mst likely reflect the availability f prey in different seasns (Tft 1980a, b). An X 2 test f independence shwed that the number f male and female frgs cllected was independent f lcatin, i.e., hill r lwland regin (X 2 = 0.18, n = 1, P = 0.74), thus, data were pled fr subsequent statistical analyses. Intraspecifically, the diet between females and males and hill and lwland are significantly different (Table 3). Frgs cllected frm the hill and lwland habitats had the lwest diet verlap prbably because prey availability frm these habitats was different. Similar findings were fund in earlier studies f anurans and newts (Ellitt and 30 Table 2. lngicrus Seasnal diet cmparisns fr Rana 10 H C Hy FDA Cr Ch I Prey Categry Fig. 6. Seasnal imprtance in prey frequency f the ten mst cmmnly recrded fd items in the diet f Rana lngicrus. 0, H, C, Hy and D are the rders Orthptera, Hmptera, Cleptera, Hymenptera, and Diptera, respectively; A, Cr, and Ch are the classes Arachinida, Crustacea, and Chilpda, respectively; F is the family Frmicidae; I is insect larvae. Summer Fall Winter Spring 69.7***b 38.7* * * 66.6* * * df = 17 c df = 16 df = Summer 2.9*** 67.4*** df = 18 df = 1 38 Fall 93.2* * * df = 16 8 is a measure f verlap index (%). bis a G value with significant prbability; * * * represents p < Cis degrees f freedm.

0 Zlgical Studies 34(3): 193-1 (199) Table 3. Diet cmparisns between females/males, frglets/adults, and hill/lwland in Rana lngicrus Cmparisn n D G p Females/males 74 27.8 0.04 Hill/lwland 60 49.4 0.

8 0 Zlgical Studies 34(3): (199) Table 3. Diet cmparisns between females/males, frglets/adults, and hill/lwland in Rana lngicrus Cmparisn n D G p Females/males Hill/lwland Frglets/adults n = the number f prey categries cmpared. D = percentage verlap in diet. G is the G test value. p = significance prbability. Karunakaran 1974). Ontgenetic changes in the number and size f prey items in R. lngicrus were als fund in many anurans and salamanders (Table 3). As an individual grws larger, the mrphlgical changes in its feeding apparatus, including the number f teeth and gape size, allw a wider selectin f prey items (Bell 197, Labanick 1976, Tft 1980a, Christian 1982). Acknwledgements: We thank M.-J. Hsu wh helped identify insects fr the stmach cntent analyses. We als thank C.-F. Yen and Y.-J. Yang fr helpful cmments n an earlier draft f the manuscript. REFERENCES Alexander PS, AC Alcala, DY Wu Annual reprductive pattern in the rice frg Rana I. Iimncharis in Taiwan. J. Asian Ecl. 1: Bachmann K Temperature adaptatins f amphibian embrys. Am. Nat. 104: Bell G The diet and dentitin f smth newt larvae (Triturus vulgaris). J. Zl. (Lndn) 176: Brwn HA Embrynic temperature adaptatins f the Pacific treefrg, Hyla regilla. Cmp Bichem. Physil. 1(A): Brwn HA The time-temperature relatin f embrynic develpment in the nrthwestern salamander, Ambystma gracile. Can. J. Zl. 4: 2-8. Christian KA Changers in the fd niche during pstmetamrphic ntgeny f the frg Pseudacris triseriata. Cpeia 1982: Ddd MHI, JM Ddd The bilgy f metamrphsis. In Physilgy f the amphibia, ed. BA Lfts. New Yrk: Academic Press, pp Duellman WE, L Trueb Bilgy f amphibians. New Yrk: McGraw-Hili Bk Cmpany. Ellitt AB, L Karunakaran Diet f Rana cancrivra in fresh water and brackish water envirnments. J. Zl. (Lndn) 174: Herreid CF II, S Kinney Temperature and develpment f the wdfrg, Rana sylvatica, in Alaska. Eclgy 48: Heyer WR Studies in larval amphibian habitat partitining. Smithsnian Cntr. ZI. 242: Ka YH, PS Alexander, VV Cheng Yang, JYL YU Annual patterns f nuptial pad and vcal sac develpment in the male Chinese bullfrg (Rana rugulsa Wiegmann). Zl. Stud. 33(2): Kuramt M Experimental hybridizatin between the brwn frgs f Taiwan, the Ryukyu Islands and Japan. Cpeia 1974(4): Kuramt M, E Furuya, M Takegami, K Yan Karytypes f several species f frgs frm Japan and Taiwan. Bull. Fukuka Univ. Educ., Pt. III. 23: Labanick GM Prey availability, cnsumptin and selectin in the cricket frg, Acris crepitans (Amphibia, Anura, Hylidae). J. Herpetl. 10: Lin JY Ovarian, fat bdy and liver cycles in the lizard Japalura swinhnis frmsensis in Taiwan (Lacertilia: Agamidae). J. Asian Ecl. 1: Liu CC, BC Hu Chinese tailless batrachians. Peiping: Ka-sue Publishing Cmpany. Lue KY The amphibians and reptiles f Taiwan. In The manuals f wildlife resurces inventry in Taiwan (2), ed. CF Yu. Taipei: Cuncil f Agriculture, Executive Yuan. Ppe CH Ntes n amphibians frm Fukien, Hainan and ther parts f China. Bull. Amer. Mus. Nat. Hist. 61: Rathcke BJ Cmpetitin and cexistence within a guild f herbivrus insects. Eclgy 7: SAS Institute, Inc SAS/STAT User's guide. Gary: SAS Inst. Inc. Schener TW Nn-synchrnus spatial verlap f lizards in patchy habitats. Eclgy 1: Seale DB Influence f amphibian larvae n primary prductin, nutrient flux, and cmpetitin in a pnd ecsystem. Eclgy 6: Skal RR, FJ Rhlf Bimetry. San Francisc: W.H. Freeman and Cmpany. Tft CA. 1980a. Feeding eclgy f thirteen syntpic species f anurans in a seasnal trpical envirnment. Oeclgia 4: Tft CA. 1980b. Seasnal variatin in ppulatins f Panamanian litter frgs and their prey cmparisn f wetter and drier sites. Oeclgia 47: Vitt LJ, RD Ohmart Eclgy, reprductin, and reprductive effrt in the iguanid lizard Ursaurus gracisus n the lwer Clrad River. Herpetlgica 31: 6-6. Wiest JA Jr Anuran successin at temprary pnds in a pst ak-savanna regin f Texas. U.S. Fish and Wildlife Res. Rept. 13: Yuan PW Ntes n the eggs, tadples and grwth f Rana lngicrus Stejneger frm Taiwan. Quart. J. Taiwan Mus. 3: Zha EM, K Adler Herpetlgy f China. New Yrk: Sciety fr the Study f Amphibians and Reptiles.

9 Kam et al. - Natural Histry f Brwn Frgs 1 長腳赤蛙生殖及食性之研究關永才 1 王慶讓 2 林曜松 2 本文報告澳底地區長腳赤蛙的自然史長腳赤蛙是陸上白天活動的種類, 在非生殖季節主要棲息在山林中 ; 當生殖季節來臨時, 青蛙即遷移到稻田中繁殖雌蛙的吻肛長大於雄蛙生殖資料顯示 : 長腳赤蛙的繁殖時間是從 1 1 月至翠年 3 月, 在 3 月開始發現小蛙, 同年 9 月吻肛長巴和成蛙相同水池旱枯及人類干擾是蝴血三十死亡的主要原因青蛙的食物包括腹足貧毛蛛形甲殼唇足及昆蟲綱的種書頁青蛙的食物在季節性別及成長過程中有顯著的不同關鐘詞 : 長腳赤蛙, 無尾兩棲類, 食性, 生殖 1 固立彰化師範大學生物學系 2 國立臺灣大學動物學系

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