Observations on the Natural History of the Mediterranean Gecko, Hemidactylus turcicus (Sauria: Gekkonidae) in Northwest Arkansas

Journal of the Arkansas Academy of Science Volume 45 Article 25 1991 Observations on the Natural History of the Mediterranean Gecko, Hemidactylus turcicus (Sauria: Gekkonidae) in Northwest Arkansas Mark A. Paulissen University of Arkansas at Fort Smith Thomas M. Buchanan University of Arkansas at Fort Smith Follow this and additional works at: http://scholarworks.uark.edu/jaas Part of the Other Animal Sciences Commons Recommended Citation Paulissen, Mark A. and Buchanan, Thomas M. (1991) "Observations on the Natural History of the Mediterranean Gecko, Hemidactylus turcicus (Sauria: Gekkonidae) in Northwest Arkansas," Journal of the Arkansas Academy of Science: Vol. 45 , Article 25. Available at: http://scholarworks.uark.edu/jaas/vol45/iss1/25 This article is available for use under the Creative Commons license: Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0). Users are able to read, download, copy, print, distribute, search, link to the full texts of these articles, or use them for any other lawful purpose, without asking prior permission from the publisher or the author. This Article is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Journal of the Arkansas Academy of Science by an authorized editor of ScholarWorks@UARK. For more information, please contact , . Journal of the Arkansas Academy of Science, Vol. 45 [1991], Art. 25 ¦ OBSERVATIONS ON THE NATURALHISTORY OF THE MEDITERRANEAN GECKO, HEMIDACTYLUS TURCICUS (SAURIA; GEKKONIDAE) IN NORTHWESTERN ARKANSAS MARKA. PAUUSSEW and THOMAS M. BUCHANAN Division of Science, Mathematics, and Engineering Westark Community College P.O. Box 3649 Fort Smith, AR 72913 ABSTRACT The Mediterranean gecko, Hemidactylus turcicus, is a small nocturnal lizard introduced into the U.S. A stable population on the campus of Westark Community College in Fort Smith, Sebastian County, Arkansas represents the northernmost U.S. population presently known. We report data on microhabitat usage, feeding behavior, reproduction, and activity patterns. This gecko is active on the outside of buildings during warm months of the year and occasionally inside buildings during the winter. It is most abundant on buildings with many crevices that are used as daytime retreats. It avoids direct illumination of artificial light and usually perches at heights greater than 7.5 meters. Geckos are not territorial during their nocturnal foraging period and employ a sit-and-wait tactic to capture insect prey. Eggs are laid in mid-June and hatch in mid August; this reproductive season is later and shorter than it is in more southern populations. Communal nesting may be employed. A nightly bimodal activity pattern was observed with peaks of activity at 2300 and 0300 after which activity declined rapidly. INTRODUCTION The Mediterranean gecko, Hemidactylus turcicus, (Gekkonidae), is a small, nocturnal lizard native to the Mediterranean area. Ithas been introduced into the western hemisphere and has colonized many areas; typically inhabiting buildings and other structures. Inthe United States, it occurs in scattered populations along the Gulf Coast from Florida to Texas, and in Arizona (Robinson and Romak, 1973; Davis, 1974; Conant, 1975). There is also a population in northern Texas (Selcer, 1986) and one in Norman, Oklahoma descended from released animals (Sievert and Sievert, 1988). A population of Hemidactylus turcicus has existed on the campus of Westark Community College inFort Smith, Arkansas (Sebastian County) since at least 1972 (T.M.Buchanan, pers. obs.). This is the northernmost U.S. population recorded and is the firstrecorded for Arkansas (Paulissen and Buchanan, 1990). There are only a few studies of the natural history of //. turcicus and these were on populations in the southernmost parts of the U.S. range (Rose and Barbour, 1968; Selcer, 1986, 1987). Data collected from a northern population add to the natural history information available for //. turcicus and permit comparison with southern populations which may help elucidate the factors that limit the range of this species. MATERIALSANDMETHODS The central campus of Westark Community College occupies approximately 8 ha in northeastern Fort Smith. The ten buildings are one or two stories tall and are constructed of brick and cement; all have outside lights. Geckos were found on all buildings except the library which was xiiltin 1987. Geckos were active on outside walls at night and generally lid during the day; they were occasionally found inside buildings during JOth day and night. Most observations were made of geckos inhabiting the Science building, a two story brick building with a large lecture room addition made of stucco and small rock. The south side of the building faces a ighted parking lot and a greenhouse is connected to the middle of the wall. The north wall faces an unlighted lawn. The east and west walls ! Present Address: Department of Biological and Environmental Sciences, McNeese State University, P.O. Box 92000, Lake Charles, LA706092000. both have doors and are litby outside lights on the building; there is also a lighted entrance on the south side. Data were collected in September and October 1988 and April through June 1989. Additional observations made over several years are also reported. Geckos were censused three to fivetimes a month between 2130 and 2330 CDT. These censuses consisted of walking slowly around the building and locating geckos with a flashlight. For each gecko seen, the following data were recorded: time, exposure (north, south, east, west), approximate height on building (<1.5 m, 1.5-4.5 m, 4.5-7.5 m, >7.5 m), amount of illumination on the lizard (total darkness, partial illumination, full illumination, or illumination from a light fixture upon which the gecko was resting), and substratum (brick, stucco and rock, cement, glass). The entire nocturnal activity pattern was quantified on 45 June 1989 by counting lizards at the beginning ofeach hour from 2000 to 0600 CDT. Data on snout-vent length (SVL), weight, and reproductive condition of females were obtained by capturing geckos from several buildings during fall1988 and spring 1989. Alllizards were examined at the time of capture and released. RESULTS ANDDISCUSSION Adultmale and female geckos did not have significantly different SVL in Fall 1988 (mean ± 1SD: males 51.9 mm ± 2.30, n=8; females 50.4 mm ± 7.74, n=8; t-test P=0.31). Measurements were therefore pooled for the 1989 sample (mean SVL 54.1 mm ± 3.64, n=22; mean weight 3.5 g ± 0.81, range 2.3-4.5 g, n=13). These SVLs are similar to those reported for geckos inFlorida (Frankenberg, 1984) and Texas (Selcer, 1986). Geckos were more abundant on buildings with outside features that could be used as daytime retreats such as fuseboxes, pipes, vents, plates supporting light fixtures, and crevices formed at the angles where walls come together. Buildings that had relatively few of these feat (...truncated)