Age and Growth of the Red-Belied Lizard, Darevskia Parvula
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/295677946 Age and growth of the red-belied lizard, Darevskia parvula Article in Animal Biology · February 2016 DOI: 10.1163/15707563-00002489 CITATION READS 1 231 5 authors, including: Ufuk Bülbül Muammer Kurnaz Karadeniz Technical University Karadeniz Technical University 26 PUBLICATIONS 110 CITATIONS 10 PUBLICATIONS 2 CITATIONS SEE PROFILE SEE PROFILE Halime Koç Bilal Kutrup Karadeniz Technical University Karadeniz Technical University 5 PUBLICATIONS 2 CITATIONS 35 PUBLICATIONS 204 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Population genetics and ecology of Caucasian salamander, M. caucasica View project All content following this page was uploaded by Ufuk Bülbül on 07 April 2016. The user has requested enhancement of the downloaded file. All in-text references underlined in blue are added to the original document and are linked to publications on ResearchGate, letting you access and read them immediately. Animal Biology 66 (2016) 81–95 brill.com/ab Age and growth of the red-belied lizard, Darevskia parvula Ufuk Bülbül∗, Muammer Kurnaz, Ali Ihsan˙ Eroglu˘ , Halime Koç and Bilal Kutrup Department of Biology, Faculty of Science, Karadeniz Technical University, 61080 Trabzon, Turkey Submitted: August 18, 2015. Final revision received: December 18, 2015. Accepted: January 20, 2016 Abstract In the present study, we investigated potential effects of some environmental climatic factors on life- history traits of two Darevskia parvula populations located at different elevation sites and evaluated age, body size, SSD and growth rate results in these lizards. The age at maturity and longevity were found to be similar in both populations. Males of the highland population had significantly larger snout-vent length and older age than those of the lowland population. Although the mean ages of females were not significantly different between the two populations, the highland population had significantly larger snout-vent length than the lowland population. Considering all individuals (both males and females), we found that specimens from the population in the higher-elevation site had significantly larger snout-vent length and older age than those of the lower-elevation site. A low level of male-biased sexual size dimorphism was observed in both populations. The growth coefficient was lower in the high-elevation site than the lower elevation site. Growth rates were not significantly dif- ferent between the populations. Our preliminary results indicate that although our studied populations were located at different elevation sites and had distinct climate, longevity, age at sexual maturity and growth rate results were similar. This may be a reason of the lower male-biased sexual size dimor- phism in both populations. Keywords Growth rate; longevity; sexual size dimorphism; skeletochronology; SVL; von Bertalanffy Introduction Many ecological studies are performed to learn about the lifespan of reptilian species (Tinkle, 1967; Davbin, 1982; Gibbons & Semlitsch, 1982; Hutton, 1986; Barbault & Mou, 1988; Frazer et al., 1991). These studies generally focused on age structure. The mark-recapture and skeletochronology are only two techniques to calculate ages of terrestrial animals (Halliday & Verrell, 1988; Gül et al., 2014). ∗ ) Corresponding author; e-mail: [email protected] © Koninklijke Brill NV, Leiden, 2016 DOI 10.1163/15707563-00002489 82 U. Bülbül et al. / Animal Biology 66 (2016) 81–95 Skeletochronology, which is known as a very effective and reliable method, is used to calculate age by using presence of growth layers in the bone tissue and counting the lines of arrested growth (LAGs) in reptilian species (Castanet, 1994; Nayak et al., 2008; Guarino et al., 2010; Kim et al., 2010; Kolarov et al., 2010; Arakelyan et al., 2013; Kurita & Toda, 2013). For age determination of Turkish reptiles, a growing number of studies has been recently performed (Altunı¸sık et al., 2013; Arakelyan et al., 2013; Tok et al., 2013; Gül et al., 2014, 2015; Üzüm et al., 2014, 2015; Kanat & Tok, 2015; Yakın & Tok, 2015). Environmental factors such as elevation, drought, and climate in the habitats of lizards affect their longevity and life history (Gül et al., 2014). As a rule, individuals from high-elevation sites and northern latitude live longer than those from low- elevation sites and southern latitudes (Wapstra et al., 2001; Roitberg & Smirina, 2006; Guarino et al., 2010). Thermal constraints may provide a possible explanation for this trend (Guarino et al., 2010). Growth rates are dependent on food availability and the thermal environment (Adolph & Porter, 1993). Previous examples of growth rate variation along biocli- matic gradients support the hypothesis that populations living at cooler sites should either grow faster (Merilä et al., 2000; Caley & Schwarzkopf, 2004; Conover et al., 2009) or compensate their slower growth rate with larger eggs and hatchlings and delayed maturity (Berven, 1982; Liao & Lu, 2010a, 2012). Lizards will grow faster at the high elevation site because of the better growth environment driven by higher precipitation levels, associated types of vegetation (e.g., deciduous forests) and, ultimately, higher productivity (Iraeta et al., 2006). The red-belied lizard, Darevskia parvula (Lantz & Cyren, 1913), is distributed in the Eastern Black Sea and Eastern Anatolia regions of Turkey and the Adjaria autonomous region of Georgia (Baran & Atatür, 1998; Ilgaz, 2009; IUCN, 2014). It has been classified at the LC (Least Concern) category in the IUCN Red List of Threatened Animals since 2009. Although Darevskia parvula lives in a large area (Trabzon, Rize, Artvin, Ardahan and Kars provinces) in Turkey (Darevsky & Eiselt, 1980; Ilgaz, 2009), there is no detailed study based on population dynamics (age structure, size, longevity, age at maturation and growth rate) on the species. Therefore, te present study aimed to assess i) the effects of some conditions (e.g., temperature and altitude) on age structure, longevity and body length, ii) the re- lationships in longevity and age at sexual maturity with sexual size dimorphism (SSD) and growth rates, in two Darevskia parvula populations located at different elevation sites in Turkey, for the first time by using skeletochronology. Material and methods Lizards were collected from two populations (Pırnallı and Kemalpa¸sa populations located in Artvin Province of Turkey) at different altitudes during the breeding season (number of permission to capture: 72784983-488.04-113808). The Pırnallı population (41°2930N, 42°0292E) is located in a highland area at an altitude of U. Bülbül et al. / Animal Biology 66 (2016) 81–95 83 1484 m a.s.l. The habitat of the population occurs in woodland. The specimens were caught in a stony place on the edge of a forest road. D. parvula lives in sympatry with D. derjugini and Lacerta media in this population. The Kemalpa¸sa popula- tion (41°2923N, 41°3123E) is located in a lowland area at an altitude of 17 m a.s.l. The specimens were caught from a rocky slope on the edge of the Hopa-Sarp highway. The active period for lizards changes from early April to early October in Pırnallı and from early April to late October in Kemalpa¸sa. The average air temperatures in daytime were recorded as 31°C and 28°C, respectively, during the sampling period (between 20-25 July 2015 for Pırnallı and 5-10 August 2015 for Kemal- pa¸sa). The mean annual temperature, precipitation, and humidity of the Pırnallı site were 10.6°C, 60.33 mm, and 71.65%, respectively. During the active period of the lizards, the mean temperature, precipitation, and humidity were 16.3°C, 78.22 mm, 69.55%, respectively. The mean annual temperature, precipitation, and humidity of the Kemalpa¸sa site were 16.3°C, 128.80 mm, and 70.81%, respectively. During the active period of the lizards, the mean temperature, precipitation, and humidity were 19.8°C, 108.17 mm, 76.57%, respectively. Within each site, the lizards were caught by hand and sexed by direct examination of sexual organs and the secondary sex characteristics (e.g., dark blue spots on the margins of ventral plates and more conspicuously red-belly in the males). Snout- vent length (SVL) was measured to the nearest 0.01 mm using a digital caliper. We quantified Sexual Size Dimorphism (SSD) with the Lovich & Gibbons (1992) index according to the following formula: SDI = (mean length of the larger sex/mean length of the smaller sex) ± 1. In this formula, +1 is used if males are larger than females and defined as nega- tive, or −1 is used if females are larger than males and defined as positive arbitrarily (Üzüm et al., 2014). For each lizard, the second phalange from the longest finger of the hind limb was clipped and preserved in 10% formalin solution for subsequent histologic analyses. After registration and toe-clipping, the lizards were released back into their natural habitats. The animals were treated in accordance with the guidelines of the local ethics committee (KTÜ.53488718-649/2014/54). A total of 92 specimens (50 ,39 and 3 subadults) were caught [46 spec- imens (22 ,22 and 2 subadults) from Pırnallı and 46 ones (28 ,17 and 1 subadult) from Kemalpa¸sa]. The procedure of skeletochronology is based on calculation of the lines of arrested growth (LAGs) in transverse sections of the mid- dle part of phalangeal diaphyses using a portion of the second phalanx from the third toe (Gül et al., 2014). However, the phalangeal LAGs could not be real age of individuals. The phalangeal LAGs are generally 1-2 years lower especially in older individuals. The LAGs in older individuals can be obscured by replacement of periosteal bone with endosteal bone (Hemelaar, 1985; Sagor et al., 1998). In pha- langes in which first LAG has been completely destroyed by endosteal resorption, 84 U.