Herpetological Monographs最新文献

{"title":"Patterns of Burrow Use by Desert Tortoises: Gender Differences and Seasonal Trends","authors":"S. Bulova","doi":"10.2307/1467077","DOIUrl":"https://doi.org/10.2307/1467077","url":null,"abstract":"Knowledge of burrow use and movement patterns, and how they are influenced by social interactions in desert tortoises, is critical to understanding habitat use in this threatened species. I examined sex differences and seasonal variation in burrow use by desert tortoises. Twentyeight free-ranging tortoises were fitted with radio transmitters and were regularly located from June-October 1992. Location and behavior of radio-tagged tortoises were recorded and occupied shelters were marked. Patterns of burrow use and co-occupancy differed between the sexes and corresponded to the reproductive cycle. Most observations were of tortoises inhabiting shelters singly. During the nesting season in June, female tortoises moved among shelters more than did males. During the mating season in August and September, males changed shelters more frequently than did females, and male-female co-occupancy was commonly observed. Consideration of burrow use patterns and associated social behavior may improve population density estimates, success of relocation management, and understanding of the epidemiology of upper respiratory tract disease.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"133"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467077","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68499093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studies on the Chemistry and Social Significance of Chin Gland Secretions in the Desert Tortoise, Gopherus agassizii","authors":"A. Alberts, D. Rostal, V. Lance","doi":"10.2307/1467075","DOIUrl":"https://doi.org/10.2307/1467075","url":null,"abstract":"The chemical structure and biological functions of chin gland secretions were examined in a group of captive desert tortoises, Gopherus agassizii, housed at the Desert Tortoise Conservation Center near Las Vegas, Nevada. Monthly measurements of the chin glands of 20 adult males were made over one year. Gland volume varied seasonally, reaching a maximum in late summer. The chin glands of socially dominant males tended to be larger than those of socially subordinate males. Among all males, there was a positive correlation between plasma testosterone levels and size of the chin glands. Behavioral experiments demonstrated that tortoises of both sexes discriminate the chin gland secretions of familiar males from those of unfamiliar males, suggesting that chin gland secretions may function in conspecific recognition. Electrophoretic studies of chin gland secretions revealed the presence of 12-17 protein components ranging in size from 25,000115,000 Daltons. Although banding patterns among males were very similar, slight individual differences existed in the number and size of high molecular weight protein components.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"116"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467075","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68499341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"BEHAVIORAL RESPONSES AND TIME ALLOCATION DIFFERENCES IN DESERT TORTOISES EXPOSED TO ENVIRONMENTAL STRESS IN SEMI-NATURAL ENCLOSURES","authors":"D. Ruby, L. C. Zimmerman, S. Bulova, C. Salice, M. O’connor, J. Spotila","doi":"10.2307/1467068","DOIUrl":"https://doi.org/10.2307/1467068","url":null,"abstract":"We tested the effect of water stress on behavior of desert tortoises in semi-natural enclosures. Populations of adult and immature desert tortoises were established at relatively high density in 4.1 ha pens at the Desert Tortoise Conservation Center near Las Vegas, Nevada. Pairs of pens received different levels of food (sod and forb patches) and water supplementation. We postulated that the relatively high densities of tortoises and the different levels of resources created different levels of environmental stress on the populations. Behavior was systematically observed during June-August 1991 and April-September 1992 for differences due to treatment (food and water supplementation versus no food and water supplementation). Behavioral observations were collected during 30 minute focal periods and periodic scan censuses of pens. Animals in the unsupplemented treatments, particularly males, moved further during focal periods than animals with supplemented diets. Movement varied significantly among months. There were no differences in feeding rates among treatments, although monthly effects were important in both treatments. Some differences between years in feeding rates appear related to rainfall patterns and presumably changes in resource availability. Interactions among animals were highest in May and September and were more frequent in unsupplemented pens. Length of morning activity period was shorter in unsupplemented pens for all months. Within treatments, supplemented females were more visible and were seen for longer periods of time during a morning activity period. Home ranges were not significantly different between treatments but showed significant sex effects. Males have larger home ranges than females, and both have larger home ranges than immature animals. When stressed by lack of water and food resources, tortoises reduced the length of above-ground activity time but attempted to compensate for this decreased time by increasing amounts of movement and feeding while active.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"27"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467068","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68498799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Behavioral Inventory of the Desert Tortoise: Development of an Ethogram","authors":"D. Ruby, H. Niblick","doi":"10.2307/1467073","DOIUrl":"https://doi.org/10.2307/1467073","url":null,"abstract":"A behavioral inventory of the desert tortoise was compiled from observations on confined tortoises in experimental pens and free-ranging tortoises within semi-natural enclosures. We describe 80 actions. Much of a tortoise's active time outside burrows is spent in feeding behavior. Display sequences have both visual and olfactory components. Aggressive and courtship sequences have similar beginnings but proceed differently as animals respond to each other. Aggressive behavior involves much headbobbing, sniffing, biting and ramming. A pushing match enables tortoises to assess body mass and determine dominance. Courtship behavior may involve trailing, circling of the female by the male, and biting and sniffing sequences before mounting. There is no rejection display by females of courting males. Comparisons between Gopherus species and related tortoise groups suggest a very conservative evolution of behavior within the Gopherus group.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"88"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467073","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68499283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Species Limits in the Genus Gerrhonotus (Squamata: Anguidae)","authors":"D. A. Good","doi":"10.2307/1467080","DOIUrl":"https://doi.org/10.2307/1467080","url":null,"abstract":"Gerrhonotus liocephalus is demonstrated to consist of at least three species rather than the single polytypic species currently recognized. Of the seven currently recognized subspecies, G. 1. aguayoi, G. 1, infernalis and G. 1. taylori become G. infernalis; G. 1. ophiurus and G. 1, loweryi become G . ophiurus; and G . 1, austrinus and G . 1. liocephalus retain the name G . liocephalus. No subspecies are recognized within any of these three species. Certain populations from western Mexico (Durango, Sinaloa, Jalisco, and Colima) remain of uncertain identity, but are tentatively referred to as G . cf, liocephalus. Evidence for these conclusions is derived from an analysis of scalation, coloration, and morphometric variation. The taxonomic history in Gerrhonotus also is discussed","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"180"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467080","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68499418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"BEHAVIORAL RESPONSES TO BARRIERS BY DESERT TORTOISES: IMPLICATIONS FOR WILDLIFE MANAGEMENT","authors":"D. Ruby, J. Spotila, S. K. Martin, S. Kemp","doi":"10.13016/M2R27T","DOIUrl":"https://doi.org/10.13016/M2R27T","url":null,"abstract":"We conducted tests on the behavioral responses of captive desert tortoises (Gopherus agassizii) to barriers and highway obstacles. Desert tortoises are slow-moving but persistent wan- derers in their natural habitat. Consequently, they move substantial distances when they meet a barrier that they cannot go around. Tortoises responded differently to solid and non-solid barriers when placed in small pens constructed of various materials. Our tests indicated that a screen mesh with small enough openings to exclude a tortoise's head was the most suitable barrier material. When tortoises were tested for 2 h periods or after an overnight stay in a barrier pen, rates of responses with barriers declined with time but tortoises continued movement along the barrier. In a choice situation, we found no preference by tortoises for following either solid or mesh barrier fences. Tortoises quickly walked past openings in a barrier which were too small to enter but easily escaped from a barrier pen within 30 min when openings of an appropriate size were available. We found tortoises willingly entered culverts under large highways and retreated from concrete highways barriers.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"144"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66548678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EFFECTS OF INCUBATION CONDITIONS ON SEX DETERMINATION, HATCHING SUCCESS, AND GROWTH OF HATCHLING DESERT TORTOISES, GOPHERUS AGASSIZII","authors":"J. Spotila, L. C. Zimmerman, Christopher A. Binckley, J. S. Grumbles, D. Rostal, A. List, E. C. Beyer, Kelly M. Phillips, S. Kemp","doi":"10.13016/M2GK2M","DOIUrl":"https://doi.org/10.13016/M2GK2M","url":null,"abstract":"Incubation temperature has a direct effect on sex determination of the desert tortoise. Low temperatures (26.0-30.6 C) produce males and high temperatures (32.8-35.3 C) produce females. Pivotal temperature is approximately 31.8 C. Macroscopic and microscopic anatomy of the gonads is similar to that of other turtles. Hatching success and survival is very good between 28.1 and 32.8 C in dry sand (-5000 kPa). Incubation at 35.3 C is lethal for 72% of the eggs and produces weak hatchlings that die within 45 days. Wet sand (-5 kPa) is lethal for desert tortoise eggs. Hatchling size was dependent upon egg size and incubation condition. Hatchlings from eggs incubated at 32.8 and 35.3 C were significantly smaller than hatchlings from eggs incubated at 28.1 and 30.6 C. Hatching mass had no effect on growth rate of hatchlings. Thus, large eggs produced large hatchlings that were larger than their siblings at 120 days of age. Hatchlings from","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"103"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66547736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cranial Morphometry of New Guinea Crocodiles (Crocodylus novaeguineae): Ontogenetic Variation in Relative Growth of the Skull and an Assessment of Its Utility as a Predictor of the Sex and Size of Individuals","authors":"P. Hall, K. Portier","doi":"10.2307/1467081","DOIUrl":"https://doi.org/10.2307/1467081","url":null,"abstract":"The cranial morphometry of New Guinea crocodiles (Crocodylus novaeguineae) was investigated to quantify ontogenetic variation in relative growth of the skull to provide possible demographic insights into commercially harvested populations. Growth attributes were, in general, linear, and univariate statistics provided estimates of size from untransformed values. Curvilinear size (total length) to age transformations were attempted through applications of three growth models: a reparameterized Richards curve, the von Bertalannfy model, and a Brody curve. Satisfactory performance was attained only through the Brody model, with reliable age estimates restricted to smaller (<2 m) individuals. The utility of relative growth ratios to correctly predict the sex of known gender animals was assessed by both parametric (multivariate discriminant analysis-DISCRIM) and nonparametric (binary tree classification analysis-CART) methods. Crossvalidation data sets were created to reduce model biases and to evaluate the correctness of classification rates. CART models consistently showed greater congruence of apparent error rates with true error rates than did DISCRIM models, while the 'best fit' models of each method closely paralleled one another in providing conservative overall ability to correctly discriminate gender from measured attributes. Skull growth occurs in three distinctive stages that mimic a saltatory ontogenetic response and are hypothesized to be related to functional foraging responses.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"203"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467081","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68498973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of Male-Male Interactions and Female Choice in the Mating System of the Desert Tortoise, Gopherus agassizii","authors":"H. Niblick, D. Rostal, T. Classen","doi":"10.2307/1467076","DOIUrl":"https://doi.org/10.2307/1467076","url":null,"abstract":"","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"124"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467076","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68499013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-Lethal Sexing Techniques for Hatchling and Immature Desert Tortoises (Gopherus agassizii)","authors":"D. Rostal, J. S. Grumbles, V. Lance, J. Spotila","doi":"10.2307/1467072","DOIUrl":"https://doi.org/10.2307/1467072","url":null,"abstract":"The development of non-lethal techniques for sexing hatchling and immature desert tortoises is critical to population and ecological studies. Two methods for sexing desert tortoises were evaluated with respect to accuracy, efficiency, and suitability to field application. Laparoscopy was found to be 100% accurate and could be used on hatchlings as small as 28 grams total body mass. Plasma testosterone was 98% accurate for juvenile and immature tortoises ranging from 69190 mm straight carapace length. Plasma testosterone is the most suitable methodology for field studies in that only a small blood sample is required for sexing purposes. Laparoscopy is 100% accurate; however, it may require holding the animal for an extended period of time.","PeriodicalId":56309,"journal":{"name":"Herpetological Monographs","volume":"8 1","pages":"83"},"PeriodicalIF":2.5,"publicationDate":"1994-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2307/1467072","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68499212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}