Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Lizard populations (Barbault, 1975, 1981; Van Devender, 1978; Lernos-Espinal and Ballinger, 1995 a). Sceloporus grammicus is a small (54 to 72 mm SVL) viviparous lizard, distributed throughout most of Mexico frorn sea leve1 to high mountain conditions. Along its range this species exhibits extensive variation in meristic and morphometric characteristics, as well as in heterozygosity values and genic polymorphism (Hall and Selander, 1973; Sites, 1980). Sceloporus grammicus is in the auturnn breeding viviparous lizard group (Guillette and Casas-Andreu, 1980), with one litter per year and parturition occurring during April, May, or June (Ortega and Barbault, 1984). However, although S. grammicus is an abundant and widespread lizard (Smith, 1939), there are relatively few studies concerning this animal. Most of these studies are of a taxonomic nature (Hall, 1973; White, 1978; Sites 1980,1983) or concern reproduction (Axtell and Axtell, 1970; Guillette and Casas-Andreu, 1980, 1981; Guillette and Sullivan, 1981; Reed and Cites, 1995). There are relatively few works dealing with ecological aspects of this lizard (Lemos-Espinal and Ballinger 1992, 1995b), and only one on the growth patterns (Lemos-Espina1 and Ballinger, 1995a). The study site, La Michilía Biosphere Reserve, is in southern Durango, México, between 104"201 and 104"07'W and 23"201 and 23"301N.The vegetation is typically an oak-pine forest but highly diversified, with 207 plant species, including 18 species of Qucrcus, and 10 species of Pinus (Martínez and Saldíwr, 1978). The climate exhibits a mean amual temperature range between 17.4 C and 20.7 C and a mean annual precipitation of 567 mm, with most of the rain concentrated in the summer. At La Michilía, summer is hurnid and hot and winter is cold and dry (Martínez and Saldívar, 1978). A study plot of 50 X 1 000 m was marked with stakes every 10 m, and censuses were made over four years during September and December 1979, March, lournal o Heqietology Vol. 33 No. 1 pp. 123-126 1999 Copyri&t 1999 %a& for tíhe ~ t u d yof ~ r n ~ h i b i a nand s Reptiles May, and Septernber 1980, each month of 1981, and March, May, and September of 1982. Each of these 20 censuses Iasted 15 d. Each day, the transect was Growth of Sceloporus grammicus in La walked by three persons for 4 to 7 h in search for lizards. For each lizard we observed we recorded the Michilía Biosphere Reserve, Mexico date, the hour, its sex, its location in relation to the ALFREDO ORTEGA-RUBIO,',-' GONZALO HALFFTER,' ROB- nearest stake, and then captured the lizard by hand. ERT BARBAULT,' ARADIT CASTEII.ANOS,%ND FEDERICO We recorded the following data; SVL and tail length SALINAS~ 'instituto de Ecología, Apdo. Postal No. 63, Xal- to the nearest 0.1 mm with a caliper and body mass aya, Veracwz 91000, México; >EcoleNormale Superieure, to the nearest 0.1 g with a Pesola spring balance. Cap46 Rue D'Ulm, Paris Cedex 05, Frunce; Tentro de Investured individuals were marked individually both by tigaciones Biológicas del Noroeste, Apdo. Postal No. 128, La toe clipping and by paint code (Tinkle, 1967).The age Paz, 23000, Baja California Sur, México classes were determined through mark-recapture methods (Ortega, 1986). Juveniles were individuals The pattern of growth 1s a key aspect in the life 1 3 mo of age, subadults were individuals between 3 history of any species (Andrews, 1982; Lemos-Espina1 and 5 mo, adults 1 were individuals reaching sexual and Ballinger, 1995a). Growth rates determine, among maturity from 5 to 12 mo, and Adults 11 were indiother imyortant attributes, the length and age reached vidual~older than one year. Using the size differences between capture and reat sexual maturity and maximum body size (Barbault, 1975; Andrews, 1976; Van Devender, 1978; Kaufmann, capture of a particular individual, the Instantaneous 1981; Parker, 1994; Smith and Ballinger, 1994). Body Growth Rate (IGR) was calculated using the formula size, in many reptiles, determines crucial reproductive of Barbault (1973):final SVL - initial SVLInumber of characteristics such as reproductive effort and clutch days between captures. Only individuals with recapsize (Barbault, 1974; 1981),as well as competitive suc- ture intervals <90 and >30 d were used in parameter cess for space and food (Fox, 1983; Tokarz, 1985). analyses. Analysis of covariance (ANCOVA; Cokal and Thus, the study of growth patterns can help to un- Rohlf, 1969) with initial SVL as the covariate and seaderstand the structure, dynamics, and dernography of son, size class, and cex as factors was used to analyze 126 SHORTER COMMUNICATIONS body weights of the Mexican high elevation lizard Sceloporus grammicus microlepidotus. J. Herpetol. 15: 366-371. , AND P. W. SULLIVAN. 1985. The reproductive and fat body cycles of the lizard Sceloporus formosus. J. Herpetol. 19:474480. HALL,W. P. 1973. Comparative population cytogenetics, speciation and evolution of the iguanid lizard genus Sceloporus. Unpubl. Ph.D. Diss., Harvard Univ., Cambridge, Massachusetts. , AND R. K. SELANDER. 1973. Hybridazation of kariotypicaliy differentiated populations in the Sceloporus grammicus complex (Iguanidae). Evolution 27:22&242. KAUFMANN, K. W. 1981. Fitting and using growth curves. Oecologia 49:293-299. LEMOS-ESPINAL, J. A., AND R. E. BALLINGER. 1992. Observations on the tolerance to freezing by the lizard, Sceloporus grammicus, from Iztaccihuatl volcano, México. Herpetol. Rev. 23:8-9. ,AND -. 1995 a. Ecology of growth of the high altitude lizard Sceloporus grammicus on the Eastern slope of Iztaccihuatl volcano, Puebla, México. Trans. Nebraska Acad. Sci. 22:77-85. , AND . 1995 b. Comparative thermal ecology of tlie high-altitude lizard Sceloporus granlmicus on tho eastern slope of the Iztaccihuatl volcano, Puebla, México. Can. J. Zool. 73:2184-2191. LICI-~T, P. 1974. llesponse of Anolis lizards to food supplementation in nature. Copeia 1974:215-221. MART~NEZ, E. AND M. SALDIVAR. 1978. Unidades de vegetación en la Reserva de la Biósfera de La Michilía en el Estado de Durango. Publicación No. 4 del Instituto de Ecología. MAUTZ,W. J. 1979. The metabolism of reclusive lizards, the Xantusiidae. Copeia 1979:577-589. ORTEGA, A. 1986. Dinámica y estrategias demográficas de dos poblaciones de iguanidos simpatricos en la reserva de la biosfera la Michilía. Unpubl. Ph.D. Diss., Instituto Politécnico Nacional. México. , AND R. BARBAULT. 1984. Reproductive cycies in the mesquite lizard Sceloporus grammicus. J. Herpetol. 18:168-175. , AND L. HERNÁNDEZ. 1983. Abundancia relativa de insectos en un medio estacional: su influencia en la historia de vidad de dos iguánidos simpátricos. Folia Entomológica. No. 55:129-144. PARKER, W. S. 1994. Demography of the fence lizard, Sceloporus uildulatus, in northern Mississippi. Copeia 1994:136-152. REED,K. M.. AND T. W. SITES.1. R. 1995. Female fecundity in a hybrid zone beiween two chromosome races of the Sceloporus xrammicus complex (Sauria, ~hr~nosomatidaé). ~vo¡ution 49:61-69 RUBY,D. E. 1977. Winter activity in Yarrow's spiny lizard, Scelop?orus jarrwi. Herpetologica 33:322-333. . 1978. Seasonal changes in the territorial behavior of the iguanid lizard Sceloporus jarrwi. Copeia 1978:430-438. SCHOENER, T. iV. 1970. Size pattems in West Indian Amlis lizards, 11. Correlations with the sizes of particular sympatric species-displacement and divergence. Amer. Natur. 104:155-174. , AND A. SCHOENER. 1978. Estimating and interpreting body-size growth in some Anolis lizards. C0pei.i 1978:390-405. CITES, J. W., JR. 1980. Chromosome allozyme, and morphometric variation in three cytotypes of the Sceloporus grammicus complex. Unpubl. Ph.D. Diss., Texas A &M Univ., College Station. . 1983. Chromosome evolution in the iguanid lizard Sceloporus grammicus. 1. Chromosome polymorphisms. Evolution 36:38-53. SMITH,H. M. 1939. The Mexican and Central American lizards of the genus Sceloporus. Field Mus. Nat. Hist., Zool. Ser. 26:l-397. SMITH,C. R. 1996. Annual life-history variation in the striped plateau lizard, Sceloporus virgatus. Can. J. ZOO~. 74:2025-2030. , AND R. E. BALLINGER. 1994. Temporal and spatial variation in individual growth in the spiny lizard, Sceluporus jarrwi. Copeia 1994:1007-1013. SOKAL, B. R., AND F. J. ROHLF.1969. Biometry. 2nd Ed. Freeman Publ. Co., San Francisco, California. SOULE,M. 1966. Trends in the insular radiation of a lizard. Amer. Natur. 100:47-64. TANNER, W. W., AND J. H. HOPKIN.1972. Ecology of Sceluporus occidentalis longipes baird and Uta stansburiana Baird and Cirard on rainier mesa, Nevada test site range county, Nevada. Brigham Young Univ. Sci. Bull. Biol. Ser. Vol. XV:1-30. TINKLE, D. W. 1967. The life and demography of the side-blotched lizard, Uta stansburiana. Misc. Publ. Mus. Zool. Univ. Michigan 132:l-182. TOKARZ, R. R. 1985. Body size as a factor determining dominance in stage agonistic encounters between male brown anoles (Anolis sagrei). Anim. Behav. 33: 746-758. TRIVERS, R. L. 1976. Sexual selection and resource-accruing abilities in Anolis garmani. Evolution 30:253269. F. B., AND C. s . CIST.1970. Observations of TURNER, lizards and tree frogs in an irradiated Puerto Rican Forest. In H. T. Odum and R. F. Pigeon (eds.), A Tropical Rain Forest, pp. E25-E49. US Atomic Energy Comm., Springfield. Virginia. VANDEVENDER, W. R. 1978. Crowth ecology of a tropical lizard, Basiliscus basiliscus basiliscus. Ecology 59:1031-1038. WEBB,C. J. W., H. MESSEL,J. CRAWFORD, AND M. J. YERBURY. 1978. Crowth rates of Crocodylus porosus from Arnhem Land, Northern Australia. Austr. Wildl. Res. 5:385-399. WHITE,M. J. D. 1978. Modes of Speciation. W. H. Freeman and Co., San Francisco. California. WILBUR, H. M. 1975. A growth model for the turtle Chrysemys picta. Copeia 1975:337-343. Accepted: 30 Ceptember 1998. 124 SHORTER COMMUNICATIONS the influence of body size on IGR. Adjusted means were tested with the Student-Newman-Keuls (SNK) Post Hoc Test (Sokal and Rohlf, 1969). IGR data were adjusted to the differential equations of the curves and models most frequently used to describe animal growth. For this purpose, we calculated the size incre,ase per day percentage, alco called Relative Growth Rate (RGR), using the method of Kaufmann (1981): in final SVL - in initial SVL/number of days between captures. RGR values were plotted against the geometric means (S) of the individual body size, S (S = (S,.S,)K). If the plotted data yields a straight line using semilog paper, a Gompertz curve can be used to describe the observed data pattern (Kaufmann, 1981). If a straight line is obtained using logarithmic paper, then a potency curve must be used and, if a straight line is obtained with linear graph paper, then the logistic or the Bertalanffy curves can be used (Bertalanffy, 1957, 1960; Kaufmann, 1981). It is possible to calculate the linear regression for the plotted data, and calculating the origin and the slope establishes the differential equation that defines the pattern observed. A total of 142 recaptures on 106 individuals were made during the four years of study. Individual data are grouped by season, sex, and age class in Table 1. IGR diminished drastically as the organisms grew. Juveniles grew much more quickly than subadults and adults (F.,,,, = 1544.26; P < 0.001), subadults grew more quickly than adults, and adults 1 grew faster than adults II (al1 P < 0.05, SNK Post Hoc Test). In the younger age classes, adult males grew more quickly than females (F,,,,,, = 19.27; P < 0.01). Among the older classes, lGRs were practically equal for males and females. lncluding juveniles and subadults in the analysis, S. gruniiiricus grew faster during spring and summer (F,,,,,= 457.57; P < 0.001), because juvenile hatchling occurs at the end of the spring. However, taking into account only adults 1, where it is possible to make comparisons among seasons, we found a significantly quicker growth during summer and autumn (F,,, = 196.54; P < 0.001) as compared with the adult 1 growth durong the spring and the winter (P < 0.05; SNK Post Hoc Tests). For adults 11, we observed significantly quicker growth during summer and autumn (F,,,,, = 34.96; P i 0.001) as compared with the spring, with the winter having the lowest values (P < 0.05; SNK Post Hoc Tests). The RGR data and the geometric meaii of the individual body size for each individual recaptured were plotted on seinilog, log, and linear paper. There was a good fit both with the semilog and linear plots. We found the best fit for the linear plot, where Y = 0.4046 x -0.i30698; r = 0.81; P < 0.05. Thus, the Bertalanffy growtli ciirve best fits the S. grcirriniicus growth data. I'reviously, i t liad bt,eii reported that for small and short-livcd lizards, the bcst model fitted is the logistic one (l'inklc 1'467; Uunhani, 1978; Aiidrews, 1982). The growth pattcrns of larger reptiles with longer life spans usually follow the Bertalanffy mcidel (Wilbur, 1975; Webb et al., 1978; Chabreck and Joanen, 1979). tiowever, the growth pattern of S. gniriiniicus at La Michilía follows the Bertalanffy model, i.e., maximum growth rates are rrachcd in the youiiger agr classcs and thest, ratcs ciecrease as the size increases. Our re- am 2 222 oooo SHORTER COMMUNICATIONS sults are ccjnsistent with those obtained for many 0ther reptiles (Turner and Gist, 1970; Trivers, 1976; Schoener and Schoener, 1978; Van Devender, 1978), in'luding other populations of grammicus(Lemos-Espina1 and Ballinger, 1995a). 'here are many interde~endent that mine growth rates including food and water availability (Andrews, 1982; Smith and Ballinger, 1994; Cmitk 1996), phenological phase of the individual (Tanner and Hopkin, 1972), inter- and intraspecific competition (Soule, 1966; Schoener, 197'4, predation (Mautz, 19791, and for lizards, tail breakage (Ballinger and Tinkle, 1979). lndividual growth varies with available energy; thus many lizard species exhibit quicker growth rates during the season of higher prey avai'ability (Smith and Ballinger, 1994; Smith, 1996) or when they have access to supplementary food (Licht, 1974). At the La Michilía Biosphere Reserve, the prey of S. grammicus are most abundant (both in number and biomass) from June to October (Ortega and Hernández, 1983). Growth rates of S. grarnmicus are highest during this same period, as we would predict, based on the well established link between prey ahundance and liziird growth (Smith and Ballinger, 1994; Smith, 1996). Most of the S. grammicus hatchlings are born of M a ~ and the first part during the second June (Ortega and Barbault, 1984). The effect of seasonality on lizard growth 1s not well documented. Our data indicate that the adult classes grew in summer autumn (Table '1. Growth rates were lower during spring and lowest Newborn durinl; the winter ( F , n= 20.I9; P < S. grairimicus individuals appear (Ortega, 1986) just when prey ahundance is starting to be the highest (Ortega and Hernandez, 1983), perhaps allowing growth at the fastest rates. The growth rates observed for younger S. gramrnicus individuals at La ~ i c h i l í a (0.390 mmiday) are higher than those reported for other Sceloporus species, such as S. 7iirgafus (0.193 mm/ day; Smith, 1996), S. irndulafus (0.300 to 0.348 mml day; Parker, 1994), and S. jarrovi (0.200 to 0.380 mm/ day; Smith and Ballinger, 1994). Comparing the S. grammicus population of la Mi&ilía with the populations studied by Lemos-Espina1 and Ballinger (1995a) at Laguna (0.074 to 0.099 mm/ day) and paredon (0.075 to 0.098 mmlday), we also found faster growth rates in the younger individuals at La Michilía. La Michilía is located in the Northwest moiintains of Mexico. The populations skdied by Lemos-Espina1 and Ballinger (1995a), Laguna and Paredon, are located in Central Mexico volcanic mountains (around 19"lO'N and 9So36'W).Both study sites are located at high elevations, Laguna at 3700 m and Paredon at 4400 m (Lemas-Espina1 and Ballinger, 1995a). 13espite marked seasonality in the rainfall al al1 three sites which is concentrated in the summer, tht. average temperature conditions are at least 8 C colder at Laguna and Paredon as compared with La Michilía. The timing of birth may result in the early maturation (five months) of S. gramniicus at La Michilía, (Ortega, 1986). Other montane Sc~lriporusspecies mature at five months, such as S. jarrmi (Ballinger, 1973; Ruby, 1977, 1978). Sixty percent of the S. jarraii females studied by Ballinger (1973) matured at five months, but the reninant matured at 17 mo. However, most temperate anti montane lizards mature at nine months to two years (Barbault, 1975). ~cknow~edgmcnis,.-This work was supported jointly by the Consejo Nacional de Ciencia y Tecnología (CONACyT), the lristituto de Ecologja, and The Gentro de investigaciones Biológicas del Noroeste (CIBNormale Cupcrieure, NOR), of México; by the Ccientifique the Council National de la (CNRS) of France and by the MAB proNiewiagram, We would like to thank to D ~ , rowski and one anonymous reviewer for their kind helpful suggestions, which highly improved an version of the manuscript, D ~ ~. l l ~i ~ l for ~ editing the English text, and to Lolita Vázquez who tyFd the manuscript. ~ Ll 1 ERATURE CI'TED ANDKEWS, R. M. 1976. Growth rate in island lizards. 1976:477-482, -. 1982. Patterns of growth in reptiles. In C. Gans and F. Pough (eds.), Biology of Reptilia, Vol. 13, pp. 273-319. Academic Press. New York. W, AXTELL. 1970, Hibernacula A, C., AND birth and young of Sce[rJporus grarnmicus disparilis (Iguanidae). Southwest. Natur. 14:363-366. BALLINCEX, R. E, 1973, Comparative demography of two viviparous iguanid lizards (Sceloporus jarrovi and ~~~l~~~~~~ poinsetti).~~~l~~~54:262-238. , AND D. W. TINKI.E1979. On the cost of tail regeneration to body growth in lizards. J. Herpetol. 13:374-375, BARI)AULT, R. 1973, Structure et dinamique d' un peuplement de iézards: les sdnddes de la savane de ~~~t~ (cate uIvoire). Unpubl. These de Doctorsciences, univ,paris VI, . 1974. Structure et dynamique d'un peuplement de lézards: les scincideSde la savane de L ~ to (Cote D'lvoire). La Tcrre et la Vie 28:352-428. . 1975. Dynamique des populations de lezards. ~ ~ 1soc. 1 . zool, F~~~~~ 99:345-361, . 1981. Ccologie des population et des peuplements. Masson Ed. Paris. BEIITALANFFY, L. 1957. Quantitative laws in metaholism and growth. Q. Rev. ~ i o l32:217-231. . -. 1960. Principies and theory of growth. Iri W. W, Nowinsky (ed.), Fundamental Aspects of Normal and Malignant Crowth, pp. 137-259. Elsevier publishing Co. Amsterdam. CHABREK, R. H., AND T. JOANEN. 1979. Growth rates of American alligators in Louisiana. Herpetologica 3.55-57. DUNHAM, A. E. 1978. Food availability as proximate factor infiuencing individual growth rates in the iguanid lizard Sceloporus merriami. Ecology 59:770778. Fox, S. F. 1983. Fitncss home range quality and aggression in Utu Sturisbirriana.In R. B. Huey, R. Pianka, and T. W. Schoener (eds.), Lizard Ecology: Ctudies of a Model Organism, pp. 149-168. Harvard Unit: Press, Cambridge, Massachusetts. GUIT.I.EI.TE, L. J., AND G. CASAS-ANDREU. 1980. Fall reproductive activity in the high altitude Mexican lizard, Sceloporus grammicus microlyidotus. J. Herpetol. 14:143-147. --, AND ---. 1981. Ceasonal variation in fat - - ~ - i ~ ~