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Popular Articles by Herilala Randriamahazo

Turtle Survival, 2014

The TSA, in partnership with Utah’s Hogle Zoo, has launched a Confiscation to Reintroduction Stra... more The TSA, in partnership with Utah’s Hogle Zoo, has launched a Confiscation to Reintroduction Strategy meant to save Madagascar’s iconic Radiated Tortoise (Astrochelys radiata). This multi-faceted initiative includes a media campaign to put attention on the plight of A. radiata; development of cooperative agreements with communities interested in conserving the animals; reduction of poaching and an increase in confiscations; establishment of triage centers to rehabilitate rescued animals; development of reintroduction strategies and sites; and creation of a regional tortoise center to maintain the initiative in southern Madagascar into the future. We’re happy to report that many elements in this plan are fast becoming a reality, which is good news for A. radiata. We provide the exciting details here.

Papers by Herilala Randriamahazo

Japanese journal of herpetology

The spatial distribution pattern and associated social interactions of Oplurus cuvieri cuvieri we... more The spatial distribution pattern and associated social interactions of Oplurus cuvieri cuvieri were studied in a deciduous dry forest of Ampijoroa, Madagascar. Home range sizes were significantly larger in males than in females. In both sexes, snout-vent length was not correlated with home range sizes. Home range of males overlapped both inter-and intrasexually. Female home ranges rarely overlapped intrasexually. Consexual aggressive interactions indicated the presence of territoriality. Distribution pattern and observed intersexual interactions suggested a polygynous mating system. Site fidelity was observed for both home range and shelter tree levels. Tail breakage was moderately frequent, implying high predation pressure and the importance of safety refuge. No sexual differences were observed in thermal environment, perch height, or perch diameter, whereas sexual dimorphism in body size and dorsal color pattern was found. More than 80% of the lizards of both sexes performed "resting" .

Current Herpetology, 2005

Animal color patterns often have functions in thermoregulation, predation avoidance, and intraspe... more Animal color patterns often have functions in thermoregulation, predation avoidance, and intraspecific communication. Examining intraspecific variation of color patterns is an effective approach to clarify their functions in a specific animal. We investigated the variation of dorsal color pattern within a dry forest population of the Madagascan iguanian lizard, Oplurus cuvieri cuvieri. Mark-and-recapture study showed that the number of dorsal black bands (DBBs) varies from one to seven, and often increases and decreases ontogenetically. Among four factors (snout-vent length, sex, age, and habitat) and three interactions between them, only sex and habitat had significant effects on the number of DBBs. Female lizards and lizards inhabiting a forested area tended to have more DBBs than males and those in an open habitat, respectively. All captive born hatchlings had seven DBBs, and juveniles reared under a 40W lamp retained more DBBs than those reared under a 60W lamp. This suggests that the number of DBBs of O. c. cuvieri is affected by thermal conditions, implying a thermoregulatory function of this color pattern.

Chelonian Research Monographs, 2013

Current herpetology, 2004

Thermal characteristics of an Iguanian lizard, Oplurus cuvieri cuvieri, were examined in a tropic... more Thermal characteristics of an Iguanian lizard, Oplurus cuvieri cuvieri, were examined in a tropical dry forest of northwestern Madagascar. This lizard is an arboreal, strictly diurnal sit-and-wait predator feeding mostly on insects. A field study was conducted from mid-September 1997 to mid-January 1998 and from late-September to mid-November 1998. Ambient air temperature significantly affected body temperature, but sex, snout-vent length, month, perching height, and posture of perching lizards did not show significant effects on body temperature. Effects of time and interaction between ambient temperature and time were significant in the first half of 1997 (dry season) and 1998, but not in the latter half of 1997. Overall body temperature was significantly correlated with ambient temperature, and slopes between them did not significantly deviate from one. However, slopes varied with time of day, and significant correlation between ambient and body temperatures diminished in the midday period. Body temperature was significantly higher than corresponding ambient temperature. In the rainy season, when ambient temperature decreases, the lizards seemed to regulate its body temperature to some extent by selecting hotter microhabitat (the ground). Collectively, although the study site is a relatively open, deciduous forest, where direct solar radiation for thermoregulation by basking is available, O. c. cuvieri exhibits intermediate features between thermoregulator and thermoconformer, having mixed characteristics of both types.

Chelonian Research Monographs, 2013

Current Herpetology, 2012

Journal of Herpetology, 2001

ABSTRACT We studied the egg-laying activities and the relationships between basic reproductive tr... more ABSTRACT We studied the egg-laying activities and the relationships between basic reproductive traits of Oplurus cuvieri cuvieri in a deciduous dry forest area of Madagascar. Oviposition was observed after the first heavy rain of the rainy season. Females migrated to the trails from their shelter trees in the forest and moved around along the trail, presumably making nest site selections. The egg-laying activities were divided into four phases: digging, laying eggs, filling, and covering. Females left the nests with a rapid bipedal locomotion after oviposition. Mean body temperature of the oviposited females was 42 degreesC. Extensive predation on the eggs by snakes was confirmed. Clutch size was variable (2-5) and depended on maternal SVL. With female body size held constant, egg mass and egg length exhibited negative correlations with clutch size. Mean relative clutch mass was 20.4%. Behavioral elements such as migrations to egg-laying site should be evaluated as the female reproductive investment as well as relative clutch mass.

Biological Conservation, 1994

Ambohitantely Special Reserve protects one of the few remaining remnants of native forest on the ... more Ambohitantely Special Reserve protects one of the few remaining remnants of native forest on the Central Plateau of Madagascar, yet its fauna is poorly studied This paper describes the first systematic small mammal trapping programme to be implemented in the reserve. Between August 1988 and March 1990, Sherman and pitfall traps revealed the presence o f four endemic tenrec .species and an introduced rat. Diurnal and nocturnal surveys recorded three lemur species. The terrestrial mammal community of Ambohitantely is compared with other reserves in Madagascar. It is concluded that the reserve has a relatively species-poor mammal fauna which may be due to its isolation from contiguous forest blocks. It is postulated that the continued presence of wild boar and domestic cattle in the reserve and regular burning of the surrounding savannah have a detrimental effect on the native fauna and flora. The consequences /'or conservation are discussed

African Journal of Ecology, 2002

The foraging mode of lizards has been extensively studied in members of most major families. One ... more The foraging mode of lizards has been extensively studied in members of most major families. One neglected taxon is Opluridae, a distinct Iguanian group endemic to Madagascar. We studied the foraging mode of Oplurus cuvieri cuvieri in a dry forest in northwestern Madagascar. Quantitative data on the number of movements per minute and percentage of time spent in moving indicated that O. c. cuvieri is a typical ambusher, although the lizard occasionally fed on plant materials by active foraging. Possible seasonal changes in foraging activity were suggested. The results support the previous view that insectivorous iguanian lizards are ambush foragers.

Chelonian Research Monographs, 2013

We updated the Global Amphibian Assessment for Malagasy amphibians, including considerations on t... more We updated the Global Amphibian Assessment for Malagasy amphibians, including considerations on the species described or resurrected between 2005-2007, and newly available information on other taxa. The revised assessment allowed us to include 66 threatened species: 6 Critically Endangered, 31 Endangered, and 29 Vulnerable. Three species formerly assessed as Critically Endangered (Mantella expectata, M. viridis, and Scaphiophryne gottlebei) are downlisted

Popular Article: The TSA, in partnership with Utah's Hogle Zoo, has launched a Confiscation t... more Popular Article: The TSA, in partnership with Utah's Hogle Zoo, has launched a Confiscation to Reintro-duction Strategy meant to save Madagascar's iconic Radiated Tortoise (Astrochelys radiata). This multi-faceted initiative includes a media campaign to put attention on the plight of A. radiata; development of cooperative agreements with communities interested in conserving the animals; reduction of poaching and an increase in confiscations; establishment of triage centers to rehabilitate rescued animals; development of reintroduction strategies and sites; and creation of a regional tortoise center to maintain the ini-tiative in southern Madagascar into the future. We're happy to report that many elements in this plan are fast becoming a reality, which is good news for A. radiata. We provide the exciting details here. MEDIA CAMPAIGN AND COMMUNITY OUTREACH A RESOUNDING SUCCESS In 2011, the TSA and its partners launched a comprehensive awareness campaign to focus attention...

Turtle and Tortoise Newsletter, 2008

7 Madagascar is one of the world's most important megadiversity countries and one of... more 7 Madagascar is one of the world's most important megadiversity countries and one of its highest priority bio-diversity hotspots, with levels of endemism at the species, genus, and family levels that are unsurpassed among the world's priority regions. Madagascar is also a country ...

Current Herpetology, 2005

Turtle Survival, 2014

The TSA, in partnership with Utah’s Hogle Zoo, has launched a Confiscation to Reintroduction Stra... more The TSA, in partnership with Utah’s Hogle Zoo, has launched a Confiscation to Reintroduction Strategy meant to save Madagascar’s iconic Radiated Tortoise (Astrochelys radiata). This multi-faceted initiative includes a media campaign to put attention on the plight of A. radiata; development of cooperative agreements with communities interested in conserving the animals; reduction of poaching and an increase in confiscations; establishment of triage centers to rehabilitate rescued animals; development of reintroduction strategies and sites; and creation of a regional tortoise center to maintain the initiative in southern Madagascar into the future. We’re happy to report that many elements in this plan are fast becoming a reality, which is good news for A. radiata. We provide the exciting details here.

Japanese journal of herpetology

The spatial distribution pattern and associated social interactions of Oplurus cuvieri cuvieri we... more The spatial distribution pattern and associated social interactions of Oplurus cuvieri cuvieri were studied in a deciduous dry forest of Ampijoroa, Madagascar. Home range sizes were significantly larger in males than in females. In both sexes, snout-vent length was not correlated with home range sizes. Home range of males overlapped both inter-and intrasexually. Female home ranges rarely overlapped intrasexually. Consexual aggressive interactions indicated the presence of territoriality. Distribution pattern and observed intersexual interactions suggested a polygynous mating system. Site fidelity was observed for both home range and shelter tree levels. Tail breakage was moderately frequent, implying high predation pressure and the importance of safety refuge. No sexual differences were observed in thermal environment, perch height, or perch diameter, whereas sexual dimorphism in body size and dorsal color pattern was found. More than 80% of the lizards of both sexes performed "resting" .

Current Herpetology, 2005

Animal color patterns often have functions in thermoregulation, predation avoidance, and intraspe... more Animal color patterns often have functions in thermoregulation, predation avoidance, and intraspecific communication. Examining intraspecific variation of color patterns is an effective approach to clarify their functions in a specific animal. We investigated the variation of dorsal color pattern within a dry forest population of the Madagascan iguanian lizard, Oplurus cuvieri cuvieri. Mark-and-recapture study showed that the number of dorsal black bands (DBBs) varies from one to seven, and often increases and decreases ontogenetically. Among four factors (snout-vent length, sex, age, and habitat) and three interactions between them, only sex and habitat had significant effects on the number of DBBs. Female lizards and lizards inhabiting a forested area tended to have more DBBs than males and those in an open habitat, respectively. All captive born hatchlings had seven DBBs, and juveniles reared under a 40W lamp retained more DBBs than those reared under a 60W lamp. This suggests that the number of DBBs of O. c. cuvieri is affected by thermal conditions, implying a thermoregulatory function of this color pattern.

Chelonian Research Monographs, 2013

Current herpetology, 2004

Thermal characteristics of an Iguanian lizard, Oplurus cuvieri cuvieri, were examined in a tropic... more Thermal characteristics of an Iguanian lizard, Oplurus cuvieri cuvieri, were examined in a tropical dry forest of northwestern Madagascar. This lizard is an arboreal, strictly diurnal sit-and-wait predator feeding mostly on insects. A field study was conducted from mid-September 1997 to mid-January 1998 and from late-September to mid-November 1998. Ambient air temperature significantly affected body temperature, but sex, snout-vent length, month, perching height, and posture of perching lizards did not show significant effects on body temperature. Effects of time and interaction between ambient temperature and time were significant in the first half of 1997 (dry season) and 1998, but not in the latter half of 1997. Overall body temperature was significantly correlated with ambient temperature, and slopes between them did not significantly deviate from one. However, slopes varied with time of day, and significant correlation between ambient and body temperatures diminished in the midday period. Body temperature was significantly higher than corresponding ambient temperature. In the rainy season, when ambient temperature decreases, the lizards seemed to regulate its body temperature to some extent by selecting hotter microhabitat (the ground). Collectively, although the study site is a relatively open, deciduous forest, where direct solar radiation for thermoregulation by basking is available, O. c. cuvieri exhibits intermediate features between thermoregulator and thermoconformer, having mixed characteristics of both types.

Chelonian Research Monographs, 2013

Current Herpetology, 2012

Journal of Herpetology, 2001

ABSTRACT We studied the egg-laying activities and the relationships between basic reproductive tr... more ABSTRACT We studied the egg-laying activities and the relationships between basic reproductive traits of Oplurus cuvieri cuvieri in a deciduous dry forest area of Madagascar. Oviposition was observed after the first heavy rain of the rainy season. Females migrated to the trails from their shelter trees in the forest and moved around along the trail, presumably making nest site selections. The egg-laying activities were divided into four phases: digging, laying eggs, filling, and covering. Females left the nests with a rapid bipedal locomotion after oviposition. Mean body temperature of the oviposited females was 42 degreesC. Extensive predation on the eggs by snakes was confirmed. Clutch size was variable (2-5) and depended on maternal SVL. With female body size held constant, egg mass and egg length exhibited negative correlations with clutch size. Mean relative clutch mass was 20.4%. Behavioral elements such as migrations to egg-laying site should be evaluated as the female reproductive investment as well as relative clutch mass.

Biological Conservation, 1994

Ambohitantely Special Reserve protects one of the few remaining remnants of native forest on the ... more Ambohitantely Special Reserve protects one of the few remaining remnants of native forest on the Central Plateau of Madagascar, yet its fauna is poorly studied This paper describes the first systematic small mammal trapping programme to be implemented in the reserve. Between August 1988 and March 1990, Sherman and pitfall traps revealed the presence o f four endemic tenrec .species and an introduced rat. Diurnal and nocturnal surveys recorded three lemur species. The terrestrial mammal community of Ambohitantely is compared with other reserves in Madagascar. It is concluded that the reserve has a relatively species-poor mammal fauna which may be due to its isolation from contiguous forest blocks. It is postulated that the continued presence of wild boar and domestic cattle in the reserve and regular burning of the surrounding savannah have a detrimental effect on the native fauna and flora. The consequences /'or conservation are discussed

African Journal of Ecology, 2002

The foraging mode of lizards has been extensively studied in members of most major families. One ... more The foraging mode of lizards has been extensively studied in members of most major families. One neglected taxon is Opluridae, a distinct Iguanian group endemic to Madagascar. We studied the foraging mode of Oplurus cuvieri cuvieri in a dry forest in northwestern Madagascar. Quantitative data on the number of movements per minute and percentage of time spent in moving indicated that O. c. cuvieri is a typical ambusher, although the lizard occasionally fed on plant materials by active foraging. Possible seasonal changes in foraging activity were suggested. The results support the previous view that insectivorous iguanian lizards are ambush foragers.

Chelonian Research Monographs, 2013

We updated the Global Amphibian Assessment for Malagasy amphibians, including considerations on t... more We updated the Global Amphibian Assessment for Malagasy amphibians, including considerations on the species described or resurrected between 2005-2007, and newly available information on other taxa. The revised assessment allowed us to include 66 threatened species: 6 Critically Endangered, 31 Endangered, and 29 Vulnerable. Three species formerly assessed as Critically Endangered (Mantella expectata, M. viridis, and Scaphiophryne gottlebei) are downlisted

Popular Article: The TSA, in partnership with Utah's Hogle Zoo, has launched a Confiscation t... more Popular Article: The TSA, in partnership with Utah's Hogle Zoo, has launched a Confiscation to Reintro-duction Strategy meant to save Madagascar's iconic Radiated Tortoise (Astrochelys radiata). This multi-faceted initiative includes a media campaign to put attention on the plight of A. radiata; development of cooperative agreements with communities interested in conserving the animals; reduction of poaching and an increase in confiscations; establishment of triage centers to rehabilitate rescued animals; development of reintroduction strategies and sites; and creation of a regional tortoise center to maintain the ini-tiative in southern Madagascar into the future. We're happy to report that many elements in this plan are fast becoming a reality, which is good news for A. radiata. We provide the exciting details here. MEDIA CAMPAIGN AND COMMUNITY OUTREACH A RESOUNDING SUCCESS In 2011, the TSA and its partners launched a comprehensive awareness campaign to focus attention...

Turtle and Tortoise Newsletter, 2008

7 Madagascar is one of the world's most important megadiversity countries and one of... more 7 Madagascar is one of the world's most important megadiversity countries and one of its highest priority bio-diversity hotspots, with levels of endemism at the species, genus, and family levels that are unsurpassed among the world's priority regions. Madagascar is also a country ...

Current Herpetology, 2005

PLoS ONE, 2014

Background: An understanding of the conservation status of Madagascar's endemic reptile species i... more Background: An understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises.