is an international peer-reviewed scientific publication series for monograph-length manuscripts,... more is an international peer-reviewed scientific publication series for monograph-length manuscripts, collected proceedings of symposia, edited compilations, and other longer research documents focused on turtles and tortoises. The series accepts contributions dealing with any aspects of chelonian research, with a preference for conservation or biology of freshwater and terrestrial turtles and tortoises. Bibliographic and other reference materials are also of potential interest.
Abstract. We used a 36-yr study of a turtle community in a northern Indiana lake to examine shell... more Abstract. We used a 36-yr study of a turtle community in a northern Indiana lake to examine shell anomalies and temporal changes in their frequency in 3 species. The overall frequency of shell anomalies was 17% in painted turtles (Chrysemys picta), 11% in northern map turtles (Graptemys geographica), and 18% in red-eared sliders (Trachemys scripta elegans), and there were more anomalies on the carapace than on the plastron in 2 species (C. picta and G. geographica). The probability that an individual would have a shell anomaly was affected negatively by year of first capture and estimated year of hatching in C. picta and by carapace length at first capture in C. picta and T. s. elegans, although the relationships were weak (all r2 ≤ 0.15). Thus, there was no suggestion of a systematic change in shell anomalies over time in the Dewart Lake turtle community.
Abstract. Body size, growth, and longevity in Northern Map Turtles (Graptemys geographica) from D... more Abstract. Body size, growth, and longevity in Northern Map Turtles (Graptemys geographica) from Dewart Lake in northern Indiana were studied from 1979 to 2016. Based on captures of 214 males (72 recaptures) and 99 females (40 recaptures), we generated von Bertalanffy growth equations which corroborated our growth curves based on counts of plastral growth rings and recaptured turtles. Females diverge from males in their faster growth by the end of their second season. Our oldest females were only 18–20 seasons old, and the oldest males were only 13–15 seasons old, suggesting a short generation time and a possible sexual difference in longevity. For the species, we detected no latitudinal pattern of size or age at maturity but found some support for a latitudinal increase in body size in accordance with Bergmann's Rule.
Laterality has been found in a variety of reptiles. In turtles, one important behaviour is the ri... more Laterality has been found in a variety of reptiles. In turtles, one important behaviour is the righting response. Here, we studied laterality of righting response of two species of freshwater turtles, the Painted Turtle (Chrysemys picta) and the Eastern Musk Turtle (Sternotherus odoratus). We found evidence of individual-level laterality in righting response inC. picta, but notS. odoratus. Neither species showed evidence of population-level laterality in righting response. Our results suggest that there is variation in the extent of laterality of righting response in turtles. Possible explanations for variation in laterality of righting response in turtles include shell shape and use of terrestrial habitats. However, more species of turtles need to be examined to demonstrate any general patterns in laterality of righting response in turtles.
... My outstanding field companions, including D. Cordier, D. Gicca, CB McElrath, P. Meylan, P.Ro... more ... My outstanding field companions, including D. Cordier, D. Gicca, CB McElrath, P. Meylan, P.Rosen, D. Takahashi, J. Thorbjarnarson, and TR Van Devender endured grueling field schedules and never hesitated to 365 Page 11. The Southwestern Naturalist ...
... Similarly, the constant of proportionality between age at maturity and adult mor-tality in tu... more ... Similarly, the constant of proportionality between age at maturity and adult mor-tality in turtles (mean = 1.10) is similar to that reported for squamates (mean = 1.33: Shine and Charnov 1992). These values are lower than those seen in fishes or shrimp (around 2.0) but higher ...
... Reactions to Odor Trails in Bullsnakes GEOFFREY R. SMITH' AND JOHN B. IV... more ... Reactions to Odor Trails in Bullsnakes GEOFFREY R. SMITH' AND JOHN B. IVERSON, Department of Biology, Earlham College, Richmond, Indiana 47374, USA. ... In D. Duvall, D. Muller-Schwarze, and R. Silverstein (eds.), Chemical Sig-nals in Vertebrates, IV, pp. 261-278. ...
Acknowledgments.-We are much indebted to Carol Horvitz for serving as courier, to the National Sc... more Acknowledgments.-We are much indebted to Carol Horvitz for serving as courier, to the National Science Foundation for support (BSR8216808 to HMS and RBS), and to Michael Grant, Chairman, Department of E.P.O. Biology, University of Colorado, for provision of facilities. The drawings (Figs. 1 and 2) are by Jan Logan and are modelled after those in Wilson and Meyer's (1971) revision of the taeniata group of Tantilla.
Female Arkansas mud turtle (Kinosteron subrubrum) mature between their sixth and eighth winters a... more Female Arkansas mud turtle (Kinosteron subrubrum) mature between their sixth and eighth winters at a plastron length of 75 to 80 mm. Vitellogenesis apparently begins in early fall and continues until the following nesting season. Ovulation and oviposition occur at least from early May through June and probably from early April to Mid-July. During this period yolked follicles continue to mature, replacing those ovulated. Egg size is not correlated with female plastron length or clutch size. Incubation period averages 106 days. Clutch size ranges from one to six, the mode being three, and is positively correlated with female plastron length. At least three clutches are laid each year. * * *
ABSTRACT Study of the population biology of the Allen Cays Rock Iguana (Cyclura cychlura inornata... more ABSTRACT Study of the population biology of the Allen Cays Rock Iguana (Cyclura cychlura inornata) in the Bahamas has been ongoing since 1980, and most aspects of the reproductive biology and demography of this taxon have been elucidated. I used recapture data to produce the first estimate of juvenile survival. Of 16 juveniles captured and marked at age 0.5 years, nine were alive at age 12.5 yrs (typical age at maturity), an annualized rate of 95.3%. Of four other juveniles marked at age 1.5 yrs, three were still alive ten years later, an annual rate of 97.2%. These rates are the highest recorded for juveniles of any lizard. A life table generated for this taxon demonstrates extreme longevity, very high survival throughout life, greatly delayed maturity (longer than for any studied lizard), extreme iteroparity, and low reproductive output. Net reproductive rate (R0 = 3.4) and cohort generation time (21 yrs) match the 3.2-fold population size increase estimated between 1982 and 2004.
Reproduction and population structure were examined for the curly-tailed lizard Leiocephalus psam... more Reproduction and population structure were examined for the curly-tailed lizard Leiocephalus psammodromus from the Caicos Islands, British West Indies, from 1973 to 1978. Females and males mature at about 65–70 and 75–80 mm snout–vent length, respectively, and at about 1.5–2 years of age. Both male and female reproduction were seasonal, with egg-laying beginning late in the dry season (late April) and ending well into the wet season (September), with hatching during the wet season (late June to December). Multiple annual clutches are probably produced. Clutch size was typically two eggs (mean = 1.72 for 42 clutches). Eggs (preserved) averaged 19.9 × 9.2 mm, and mean preserved egg mass was 1.04 g. Fat-body mass in both males and females decreases with the onset of the reproductive season. The age/size structure of the population varied from month to month, depending on recruitment of hatchlings. Reproduction in Leiocephalus psammodromus is similar to that of other tropical lizards in...
Melanism in turtles is generally rare among species, but can be extremely common in some species ... more Melanism in turtles is generally rare among species, but can be extremely common in some species and subspecies. Pond Sliders (Trachemys scripta) show ontogenetic melanism with larger, and presumably older, individuals often showing melanism of the plastron and other body parts (Lovich et al., 1990). Previous studies of melanism in T. scripta have found that the proportion of melanistic individuals can vary among populations. for example, some populations from oklahoma show 100% melanism for both adult males and females, whereas other populations from that state show percentages of melanistic adults ranging from 44% to 75% (mccoy, 1967; hays & mcBee, 2009). in southeastern missouri, 81% of adult males were melanistic (Glorioso et al., 2010), and in southern illinois, approximately 18.7% of adult male T. scripta were melanistic (reehl et al., 2006). Some authors have argued the observed variation in the proportion of melanistic T. scripta does not appear to be related to geographic p...
Cuban treefrogs (Osteopilus septentrionalis) are potential threats to native amphibians and repti... more Cuban treefrogs (Osteopilus septentrionalis) are potential threats to native amphibians and reptiles as competitors or predators of native species (see meshaka, 2001). the known distribution of the Cuban treefrog has been expanding in recent years as introduced populations are documented (e.g., Kraus, 2009), and further expansion is likely with projected climate changes (rödder & Weinsheimer, 2009). Knowledge of the reproduction and the timing of reproduction of Cuban treefrogs throughout their native and introduced ranges might be useful in understanding their ability to expand their range. however, published observations on the timing of reproduction in the Cuban treefrog are somewhat rare, especially given their rapidly expanding range. Cuban treefrogs typically breed in temporary pools, and breeding appears associated with rainfall or thunderstorms (e.g., meshaka, 2001; henderson & Powell, 2009), and can take place over an extended range of months (see meshaka, 2001; henderson &...
is an international peer-reviewed scientific publication series for monograph-length manuscripts,... more is an international peer-reviewed scientific publication series for monograph-length manuscripts, collected proceedings of symposia, edited compilations, and other longer research documents focused on turtles and tortoises. The series accepts contributions dealing with any aspects of chelonian research, with a preference for conservation or biology of freshwater and terrestrial turtles and tortoises. Bibliographic and other reference materials are also of potential interest.
Abstract. We used a 36-yr study of a turtle community in a northern Indiana lake to examine shell... more Abstract. We used a 36-yr study of a turtle community in a northern Indiana lake to examine shell anomalies and temporal changes in their frequency in 3 species. The overall frequency of shell anomalies was 17% in painted turtles (Chrysemys picta), 11% in northern map turtles (Graptemys geographica), and 18% in red-eared sliders (Trachemys scripta elegans), and there were more anomalies on the carapace than on the plastron in 2 species (C. picta and G. geographica). The probability that an individual would have a shell anomaly was affected negatively by year of first capture and estimated year of hatching in C. picta and by carapace length at first capture in C. picta and T. s. elegans, although the relationships were weak (all r2 ≤ 0.15). Thus, there was no suggestion of a systematic change in shell anomalies over time in the Dewart Lake turtle community.
Abstract. Body size, growth, and longevity in Northern Map Turtles (Graptemys geographica) from D... more Abstract. Body size, growth, and longevity in Northern Map Turtles (Graptemys geographica) from Dewart Lake in northern Indiana were studied from 1979 to 2016. Based on captures of 214 males (72 recaptures) and 99 females (40 recaptures), we generated von Bertalanffy growth equations which corroborated our growth curves based on counts of plastral growth rings and recaptured turtles. Females diverge from males in their faster growth by the end of their second season. Our oldest females were only 18–20 seasons old, and the oldest males were only 13–15 seasons old, suggesting a short generation time and a possible sexual difference in longevity. For the species, we detected no latitudinal pattern of size or age at maturity but found some support for a latitudinal increase in body size in accordance with Bergmann's Rule.
Laterality has been found in a variety of reptiles. In turtles, one important behaviour is the ri... more Laterality has been found in a variety of reptiles. In turtles, one important behaviour is the righting response. Here, we studied laterality of righting response of two species of freshwater turtles, the Painted Turtle (Chrysemys picta) and the Eastern Musk Turtle (Sternotherus odoratus). We found evidence of individual-level laterality in righting response inC. picta, but notS. odoratus. Neither species showed evidence of population-level laterality in righting response. Our results suggest that there is variation in the extent of laterality of righting response in turtles. Possible explanations for variation in laterality of righting response in turtles include shell shape and use of terrestrial habitats. However, more species of turtles need to be examined to demonstrate any general patterns in laterality of righting response in turtles.
... My outstanding field companions, including D. Cordier, D. Gicca, CB McElrath, P. Meylan, P.Ro... more ... My outstanding field companions, including D. Cordier, D. Gicca, CB McElrath, P. Meylan, P.Rosen, D. Takahashi, J. Thorbjarnarson, and TR Van Devender endured grueling field schedules and never hesitated to 365 Page 11. The Southwestern Naturalist ...
... Similarly, the constant of proportionality between age at maturity and adult mor-tality in tu... more ... Similarly, the constant of proportionality between age at maturity and adult mor-tality in turtles (mean = 1.10) is similar to that reported for squamates (mean = 1.33: Shine and Charnov 1992). These values are lower than those seen in fishes or shrimp (around 2.0) but higher ...
... Reactions to Odor Trails in Bullsnakes GEOFFREY R. SMITH' AND JOHN B. IV... more ... Reactions to Odor Trails in Bullsnakes GEOFFREY R. SMITH' AND JOHN B. IVERSON, Department of Biology, Earlham College, Richmond, Indiana 47374, USA. ... In D. Duvall, D. Muller-Schwarze, and R. Silverstein (eds.), Chemical Sig-nals in Vertebrates, IV, pp. 261-278. ...
Acknowledgments.-We are much indebted to Carol Horvitz for serving as courier, to the National Sc... more Acknowledgments.-We are much indebted to Carol Horvitz for serving as courier, to the National Science Foundation for support (BSR8216808 to HMS and RBS), and to Michael Grant, Chairman, Department of E.P.O. Biology, University of Colorado, for provision of facilities. The drawings (Figs. 1 and 2) are by Jan Logan and are modelled after those in Wilson and Meyer's (1971) revision of the taeniata group of Tantilla.
Female Arkansas mud turtle (Kinosteron subrubrum) mature between their sixth and eighth winters a... more Female Arkansas mud turtle (Kinosteron subrubrum) mature between their sixth and eighth winters at a plastron length of 75 to 80 mm. Vitellogenesis apparently begins in early fall and continues until the following nesting season. Ovulation and oviposition occur at least from early May through June and probably from early April to Mid-July. During this period yolked follicles continue to mature, replacing those ovulated. Egg size is not correlated with female plastron length or clutch size. Incubation period averages 106 days. Clutch size ranges from one to six, the mode being three, and is positively correlated with female plastron length. At least three clutches are laid each year. * * *
ABSTRACT Study of the population biology of the Allen Cays Rock Iguana (Cyclura cychlura inornata... more ABSTRACT Study of the population biology of the Allen Cays Rock Iguana (Cyclura cychlura inornata) in the Bahamas has been ongoing since 1980, and most aspects of the reproductive biology and demography of this taxon have been elucidated. I used recapture data to produce the first estimate of juvenile survival. Of 16 juveniles captured and marked at age 0.5 years, nine were alive at age 12.5 yrs (typical age at maturity), an annualized rate of 95.3%. Of four other juveniles marked at age 1.5 yrs, three were still alive ten years later, an annual rate of 97.2%. These rates are the highest recorded for juveniles of any lizard. A life table generated for this taxon demonstrates extreme longevity, very high survival throughout life, greatly delayed maturity (longer than for any studied lizard), extreme iteroparity, and low reproductive output. Net reproductive rate (R0 = 3.4) and cohort generation time (21 yrs) match the 3.2-fold population size increase estimated between 1982 and 2004.
Reproduction and population structure were examined for the curly-tailed lizard Leiocephalus psam... more Reproduction and population structure were examined for the curly-tailed lizard Leiocephalus psammodromus from the Caicos Islands, British West Indies, from 1973 to 1978. Females and males mature at about 65–70 and 75–80 mm snout–vent length, respectively, and at about 1.5–2 years of age. Both male and female reproduction were seasonal, with egg-laying beginning late in the dry season (late April) and ending well into the wet season (September), with hatching during the wet season (late June to December). Multiple annual clutches are probably produced. Clutch size was typically two eggs (mean = 1.72 for 42 clutches). Eggs (preserved) averaged 19.9 × 9.2 mm, and mean preserved egg mass was 1.04 g. Fat-body mass in both males and females decreases with the onset of the reproductive season. The age/size structure of the population varied from month to month, depending on recruitment of hatchlings. Reproduction in Leiocephalus psammodromus is similar to that of other tropical lizards in...
Melanism in turtles is generally rare among species, but can be extremely common in some species ... more Melanism in turtles is generally rare among species, but can be extremely common in some species and subspecies. Pond Sliders (Trachemys scripta) show ontogenetic melanism with larger, and presumably older, individuals often showing melanism of the plastron and other body parts (Lovich et al., 1990). Previous studies of melanism in T. scripta have found that the proportion of melanistic individuals can vary among populations. for example, some populations from oklahoma show 100% melanism for both adult males and females, whereas other populations from that state show percentages of melanistic adults ranging from 44% to 75% (mccoy, 1967; hays & mcBee, 2009). in southeastern missouri, 81% of adult males were melanistic (Glorioso et al., 2010), and in southern illinois, approximately 18.7% of adult male T. scripta were melanistic (reehl et al., 2006). Some authors have argued the observed variation in the proportion of melanistic T. scripta does not appear to be related to geographic p...
Cuban treefrogs (Osteopilus septentrionalis) are potential threats to native amphibians and repti... more Cuban treefrogs (Osteopilus septentrionalis) are potential threats to native amphibians and reptiles as competitors or predators of native species (see meshaka, 2001). the known distribution of the Cuban treefrog has been expanding in recent years as introduced populations are documented (e.g., Kraus, 2009), and further expansion is likely with projected climate changes (rödder & Weinsheimer, 2009). Knowledge of the reproduction and the timing of reproduction of Cuban treefrogs throughout their native and introduced ranges might be useful in understanding their ability to expand their range. however, published observations on the timing of reproduction in the Cuban treefrog are somewhat rare, especially given their rapidly expanding range. Cuban treefrogs typically breed in temporary pools, and breeding appears associated with rainfall or thunderstorms (e.g., meshaka, 2001; henderson & Powell, 2009), and can take place over an extended range of months (see meshaka, 2001; henderson &...
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