Chameleons in Bobaomby (Madagascar)

Chameleons in Bobaomby (Madagascar)

Verbreitung Science

The Bobaomby complex is located at the northernmost tip of Madagascar, north and west of the largest coastal town in the north, Antsiranana (Diego Suarez in French). It consists of dry forest at sea level up to a maximum of 200 metres above sea level as well as extensive savannahs on karst rock and various rock formations. The area has not been protected to date.

Scientists from Madagascar conducted reptile counts in the Bobaomby complex in 2018. The counts were carried out in February and March, i.e. during the rainy season. Five different locations were analysed: Beantely, Antsisikala and Ambanililabe as examples of varying degrees of degraded dry forest, Anjiabe for its intact dry forest and Ampombofofo with relatively intact forest. To find animals, the visual survey was used on 25 days during the day and at night in selected transects, sometimes specifically in suitable habitats such as leaf axils or under dead tree trunks, and pitfall traps along erected fences were also used.

A total of 42 reptile species have been recorded. All of them, except one gecko species, originally only occur on Madagascar, while two other gecko species are now also found on neighbouring islands. There is a small novelty among the chameleons: the leaf chameleon Brookesia ebenaui was recorded for the first time in Bobaomby, more precisely in Beantely. Brookesia stumpffi and Furcifer petteri were found in Beantely, Anjiabe and Ampombofofo. Furcifer pardalis and Furcifer oustaleti occurred as expected throughout the whole Bobaomby complex.

The authors suggest that the Bobaomby complex – especially the three forests where most of the reptiles were found – should be protected to preserve the local herpetofauna.

Overview of reptile diversity from Bobaomby complex, northern tip of Madagascar
Randriamialisoa, Raphali R. Andriantsimanarilafy, Alain J. Rakotondrina, Josué A. Rakotoarisoa, Nasaina T. Ranaivoson, Jeanneney Rabearivony, Achille P. Raselimanana
Animals 13: 3396, 2023
DOI:  10.3390/ani13213396

Photo: Furcifer petteri, male, in the north of Madagascar, photographed by Alex Laube

The Indian Chameleon in Solapur (India)

The Indian Chameleon in Solapur (India)

Verbreitung Science

It has long been known that the Indian chameleon occurs in Maharashtra. A recently published survey study has even found evidence of it in an area near Solapur that is covered only with grass and bushes.

The area studied is a 15 km² area of semi-arid grassland around a site earmarked for an airport at an altitude of 450 to 500 metres. The nearest village is Boramani, a small town just outside the city of Solapur in the state of Maharashtra in western India. For one year, about half of the grassland was surveyed four times a month for the presence of reptiles. Squares of 50 metres x 50 metres were laid out, each at least 300 metres apart. Each observation period consisted of five hours and only observations with the naked eye.

During the study period, 888 individuals of 14 different reptile species were recorded. Of these, more than 300 were Sitana laticeps, a fan-throated lizard. Among the species found were two Chamaeleo zeylanicus. The activity of the lizards increased from March, stabilised during the monsoon season in June-July and then declined again from August.

The authors argue in favour of protecting the grassland area due to the existing biodiversity. This should prevent the construction of the airport and thus the disappearance of the habitat.

Ecology of lizards in an ecologically significant semi-arid grassland patch near Solapur, Maharashtra, India
Mahindrakar Yogesh Y., Waghmare Akshay M., Hippargi Rajshekhar V.
International Journal of Zoological Investigations 9 (2) 2023, pp. 210-223
DOI: 10.33745/ijzi.2023.v09i02.022

Chameleons in the Montagne des Français (Madagascar)

Chameleons in the Montagne des Français (Madagascar)

Verbreitung Science

The Montagne des Français is a limestone massif with dry forest in northern Madagascar. It reaches up to 425 m above sea level and is within sight of the largest coastal town in the north, Antsiranana (French Diego Suarez). It has been a protected area since 2007. Scientists from Madagascar and the USA conducted counts of reptiles and amphibians in the Montagne des Français in 2014 and 2020.

Counts were made in January and May, i.e. during and at the end of the rainy season. In 2014, the focus was on the region around Andavakoera, while in 2020 it was on Sahabedara, Ampitiliantsambo, and Andavakoera. In order to find animals, the search was conducted during the day and at night along predefined paths, partly in suitable habitats, and partly in pitfall pits.

A total of 20 amphibian and 50 reptile species were recorded. Four new amphibians and one reptile were found for the first time in the Montagne des Français. The snake Langaha pseudoalluaudi was discovered again for the first time since 2007. Among the chameleons, there were minor new discoveries. Brookesia stumpffi could only be found in 2014, but no longer in 2020 – however, due to the relatively wide distribution of the species, this should not be a problem for the entire population. Brookesia tristis, one of the smallest chameleons in the world, was also only seen in 2014. Here, the body size, which makes it very difficult to find, and the time of year (May is relatively late for this species) could play a role. Brookesia ebenaui was detected in Andavakoera in 2014 and in Sahabedara in 2020. The two tree dwellers Furcifer oustaleti and Furcifer pardalis were found in both years in Andavakoera and Ampitiliantsambo. Furcifer petteri, on the other hand, was present at all the sites surveyed in both years.

Amphibians and reptiles of the “Montagne des Français”: Update of the distribution and regional endemicity
Herizo Oninjatovo Radonirina, Bernard Randriamahatantsoa, Rabibisoa Harinelina Christian Nirhy, Christopher J. Raxworthy
Preprint
DOI: 10.20944/preprints202306.1499.v1

Photo: Furcifer petteri on Madagascar, photographed by A. Laube

Panther chameleons in Madagascar

Panther chameleons in Madagascar

General topics Verbreitung Newspaper articles

In the bi-monthly magazine of the DGHT e.V., the Elaphe, a nice article on the panther chameleons of Madagascar has been published. It was written by two members of the AG Chamäleons who regularly travel to the island.

The article describes in words and pictures the distribution area of the panther chameleons on Madagascar, which extends over the northern half of the island, more precisely from a few kilometres south of the village of Ankaramibe in the northwest to the north of Madagascar and down the east coast to about 90 km south of the port city of Toamasina. The chameleons are found mainly in secondary vegetation in open landscapes, but also in cocoa plantations, overgrown gardens and rainforests.

The life cycle of the panther chameleons in Madagascar is mainly determined by the rainy season between November and March. The chameleons mate during this time. After 30 to 40 days, the females lay between 11 and 35 eggs in a nest they have dug themselves. The young hatch only in the next rainy season.

The article goes into particular detail about the different local forms, the different colour appearance of the male panther chameleons depending on the location. The authors currently count more than 30 different local forms on Madagascar, which are separated from each other by natural barriers such as rivers. There are probably many more, but not all of them have been discovered yet.

Pantherchamäleons (Furcifer pardalis) – Meister der Farben
Thorsten Negro and Alexandra Laube
Elaphe 3, 2023, pp. 12-25

Photo: Panther chameleon of the local form Ambanja on Madagascar, photographed by Thorsten Negro.

New distribution data on Chamaeleo zeylanicus

New distribution data on Chamaeleo zeylanicus

Verbreitung Science

A biologist from India has published findings of the Indian Chameleon (Chamaeleo zeylanicus) that narrow down the distribution of the species more precisely. The Aravalli Mountains are located about 150 km west of the Indian capital New Delhi in northwest India. It runs for 670 km in a south-westerly direction, passing through three different states: Haryana, Rajasthan, and Gujarat. Until now, the Indian chameleon was thought to occur in the south and centre of Rajasthan, but was not common in the north, east, or west. So far, no findings had been documented from Haryana at all.

The biologist describes six observations of the Indian Chameleon between 2015 and 2022, during which Chamaeleo zeylanicus was seen four times in the Sariska Tiger Reserve and once each at Manesar and Damdama lakes, at altitudes between 223 and 476 m asl. The former is in northern Rajasthan, the two lakes not far from it in southern Haryana. The forest of the site in the Sariska Tiger Reserve is dominated by Indian lungwort (Adhatoda vasica), prairie mugwort (Parthenium integrifolium) and mesquite tree (Prosopis juliflora). The chameleons found in Haryana were found on roadsides with carira (Capparis decidua) and mesquite trees.

New distributional records of Asian Chameleons (Chamaeleo zeylanicus Laurenti 1768), from the Northern Aravali Hill range, India
Debaprasad Sengupta
Reptiles & Amphibians 30 (1), 2023: pp. 1-2
DOI: 10.17161/randa.v30i1.18614

The Indian Chameleon in Jhalawar (India)

The Indian Chameleon in Jhalawar (India)

Science

Three scientists from India have recently published a survey of reptile and amphibian occurrences. The Jhalawar study area is located at the southernmost tip of the state of Rajasthan in northwest India. It is located on the edge of the Malwa Plateau, a volcanic highland. The area lies well to the southwest of the Ganges River, which is generally considered the distribution limit of the Indian Chameleon (Chamaeleo zeylanicus). The climate is divided into a long summer season and a shorter winter, which lasts from October to February. During the summer, temperatures above 45°C are common, while in winter temperatures can drop to as low as 1°C.

The three researchers were on site for about six hours each for 70 days. To search for reptiles and amphibians, they rummaged through loose soil as well as the foliage layer and visually searched for animals in parallel. 45 different species of reptiles and amphibians were found. Chamaeleo zeylanicus was documented for the first time in Rajasthan.

Herpeto-faunal diversity study: Analysis and critical observations from south-eastern Rajasthan, India
Yadav Vijay Kumar, Nama Krishnendra Singh, Sudhindran Rimal
Indian Journal of Ecology 49 (5), 2022: pp. 1581-1587
DOI: 10.55362/IJE/2022/3700

Chamaeleo gracilis in Taï National Park (Côte d’Ivoire)

Chamaeleo gracilis in Taï National Park (Côte d’Ivoire)

Science

Little is known about chameleons in the Republic of Côte d’Ivoire. Ivorian biologists have now confirmed the presence of various reptile species in one of the country’s national parks. For the first time, they have found Chamaeleo gracilis in Taï National Park, which matches its known range in West Africa.

Taï National Park is located in the southwest of Côte d’Ivoire in western Africa. The climate changes four times a year. From March to June there is a rainy season, in August it is dry, followed by a second rainy season in September and October and a second dry season from November to March. 40 areas, each 50 x 50 m in size, were surveyed. Of these, 18 were in primary forest (rainforest), seven in secondary vegetation with more shrubby growth, five in coffee or cocoa plantations, five in rubber tree plantations and five in rice fields. On each of 40 days, three researchers were in the demarcated areas for more than eight hours and visually scanned the surroundings for reptiles.

Chamaeleo gracilis was the only reptile observed exclusively in the rainforest. As is often the case with chameleons, a female was discovered laying eggs on the ground. The species was not found in secondary vegetation or agricultural landscapes.

First record of seven species of lizards in Taï National Park (South West, Côte d’Ivoire)
Kouadio Atta Léonard, Assemian N’guessan Emmanuel, Goly N’guessan Simplice, Keita Gaoussou, Tiédoué Manouhin Roland
International Journal of Zoological and Entomological Letters 2022, 2(2): 36-41
DOI: not available

Factors in the geographical dispersal of chameleons

Factors in the geographical dispersal of chameleons

Science

For a long time, people have been trying to find out how and why chameleons have spread across the African continent, to islands and as far as Europe and Asia. French scientists, in collaboration with international colleagues, have now used phylogenetics and various computational models to investigate how the factors of body size, coastal habitat and extreme lifestyles may have affected the distribution of different chameleon species. The study examined 181 species divided into nine main biogeographical regions: North Africa and Arabia, Central Africa, Southeast Africa, Southwest Africa, India, Socotra, Madagascar, Comoros and Seychelles.

Chameleon species that occurred more than 10 km from the sea historically spread significantly less than the 74 coastal chameleon species. A similar phenomenon is known from skinks and crocodiles. Dispersal probably took place mainly along the coasts, mostly on the same continent and only rarely across the water to other continents or islands.

The size of the different chameleons also seems to have influenced their dispersal throughout history: Large chameleons spread further and more frequently than small chameleons. This could be related to the fact that larger chameleons have a lower metabolic rate – so they need less energy overall relative to smaller competitors. In addition, larger chameleons lay clutches with significantly more eggs, which simply gives them an advantage in numbers.

A somewhat unexpected result came from the study of different life cycles. One would initially assume that short life cycles are associated with faster dispersal. In fact, the calculations showed that especially chameleon species with extreme life cycles spread further. Thus, those that reproduced particularly slowly or particularly quickly were historically more successful among chameleons than the species “in the middle”. In this regard, the authors consider whether particularly slow life cycles with late sexual maturity and long gestation might be more successful on the same continent, while faster reproductive strategies with large clutches are more favourable for dispersal across the sea to islands and other continents. In line with this, Furcifer polleni and Furcifer cephalolepis in Comoros and Chamaeleo zeylanicus in India, all three examples of aquatic dispersal, have a very fast life cycle.

The 34 chameleon species with the combination of living close to the coast, large size and extreme life cycle had a 98% higher dispersal rate than species without these characteristics.  All in all, this is certainly a very theoretical study, but it nevertheless provides exciting insights into the historical distribution and dispersal of chameleons.

Chameleon biogeographic dispersal is associated with extreme life history strategies
Sarah-Sophie Weil, Laurie Gallien, Sébastien Lavergne, Luca Börger, Gabriel W. Hassler, Michaël P.J. Nicolaï & William L. Allen
Ecography
DOI: 10.1111/ecog.06323