What kills chameleons in zoos?

What kills chameleons in zoos?

Tiermedizin Science

Scientists at the University of Veterinary Medicine Montréal (France) recently analysed the causes of death in chameleons kept in zoos between 2011 and 2022. The Zoological Information Management System (ZIMS) was used to search for zoos that currently keep chameleons or have kept them since 2011. Questionnaires were sent to a total of 245 zoos. The questionnaires asked about the number, species and sex of chameleons kept, as well as selected husbandry conditions (coolest and warmest temperatures, humidity, feeding) and dissection results.

Around 1000 chameleons of 36 different species are currently kept in zoos worldwide. 65 of the zoos surveyed took part in the study, 48 of which regularly carried out dissections on chameleons. However, only 29 of the participating zoos were able to provide dissection results. A total of 412 pathological findings from 14 different chameleon species were analysed. Among the species kept were Brookesia stumpffi, Brookesia superciliaris, chameleons of the genus Brookesia without species identification, Calumma parsonii, Chamaeleo calyptratus, Chamaeleo chamaeleon, Furcifer lateralis, Furcifer oustaleti, Furcifer pardalis, Rieppeleon brevicaudatus, Trioceros melleri, Trioceros montium and Trioceros quadricornis. Panther chameleons were kept most frequently (226 specimens).

The statistical analysis showed that most of the chameleons in the participating zoos died of infectious diseases (46.8%). Infectious diseases included septicaemia, but also inflammation of the oral cavity, lungs, liver, kidneys and intestines. Almost 20% of the infectious diseases were in the area of the oral cavity. The most common bacteria were Enterococcus and Pseudomonas. Among the fungi, Nannizziopsis including CANV, Fusarium and Metarhizium were represented. A good third of the necropsy reports also indicated parasitoses, with these occurring both as a cause of death and as an incidental finding. Coccidia and trematodes as well as various nematodes were often present. The second most common cause of death in the participating zoos was non-infectious kidney diseases (11.4%). This was closely followed by diseases of the reproductive tract, including egg loss and egg yolk coelomitis, which accounted for 10.7% of cases.

Contrary to the authors’ initial assumption, there was no correlation between the surveyed husbandry parameters in the cages and the incidence of kidney disease. Basically, there was a tendency towards an increased incidence of kidney disease in countries where the average humidity was generally lower.

Evaluation of mortality causes and prevalence of renal lesions in zoo-housed chameleons: 2011-2022
Amélie Aduriz, Isabelle Lanthier, Stéphane Lair, Claire Vergnau-Grosset
Journal of Zoo and Wildlife Medicine 55(2), 2024
DOI: 10.1638/2023-0023

Photo: Panther chameleon in Madagascar, photographed by Alex Negro

The Common Chameleon in Belezma (Algeria)

The Common Chameleon in Belezma (Algeria)

Verbreitung Science

The Belezma Biosphere Reserve was only established in 2015 and is located in the province of Batna in northern Algeria. It covers an area of 262 km² in the Belezma Mountains and lies at altitudes between 915 and 2136 metres above sea level. The terrain consists of Mediterranean cedar, pine and oak forests, typical scrubland (so-called maquis), cliffs and only seasonal watercourses (so-called oueds); around 53 km² consist of cedar forest. So far, there have only been a few publications on the herpetofauna there. A recent overview study of the amphibians and reptiles found there has now been compiled by biologists from the University of Batna.

Maquis in Belezma Biosphere Reserve

The animals were searched for visually only. Various people walked transects unsystematically both during the day and at night, for a total of 500 hours at 28 locations within the reserve. The animals found were either identified directly or photographed and released.

A total of 23 amphibian and reptile species were found and identified. Chamaeleo chamaeleon was identified for the first time in Belezma. The chameleons were found at around 1040 metres in the characteristic shrublands and at 1280 metres in open terrain. The maquis in Belezma consists mainly of oak and olive trees as well as mastic bushes and Phoenician juniper.

Herpetofauna of Belezma Biosphere Reserve, province of Batna, northeastern Algeria
Messaoud Saoudi, Mohamed Bensaci, Abdeldjabar Necer, Houria Baazi, Zohra Nemili, Farouk Khelfaoui
African Journal of Biological Sciences 6 (15), 2024
DOI: 10.48047/AFJBS.6.15.2024.10672-10700

Dwarf chameleons in South Africa larger in urban environments than in the wild

Dwarf chameleons in South Africa larger in urban environments than in the wild

Science

Dwarf chameleons of the genus Bradypodion from South Africa have long been known to adapt very well to urban habitats. Two scientists from Cape Town and Johannesburg have now investigated how different populations differ in body size, body weight and body condition score within urban and natural environments.

A total of 1107 individuals of five different dwarf chameleon species were studied over a period of four years. Bradypodion damaranum in George (Western Cape), Bradypodion melanocephalum in Durban (KwaZulu-Natal), Bradypodion setaroi in St Lucia (KwaZulu-Natal), Bradypodion thamnobates in Howick (KwaZulu-Natal) and Bradypodion ventrale in Jeffrey’s Bay (Eastern Cape) were each searched at night at three to eight locations. Forest fragments, grass savannahs or coastal bushland less than 15 km from the centre of the nearest town were classified as ‘natural sites’. All sites located within a city and consisting of both introduced and native flora regularly cut back by humans (gardens, public parks and green spaces, roadsides) were categorised as ‘urban’. The dwarf chameleons found were measured, weighed, sexed and marked with a felt-tip pen to avoid duplicate measurements on the same animals. Obviously pregnant females were not measured.

Statistical analyses and comparisons revealed that the chameleons at natural sites were always smaller and lighter on average than the populations of the same species at urban sites. Significantly larger and heavier in the city were both sexes in Bradypodion damaranum, the males in Bradypodion melanocephalum, ventrale and setaroi and the females in Bradypodion thamnobates. The body condition score was higher in urban areas for both sexes of Bradypodion damaranum and setaroi and males of Bradypodion melanocephalum than for the chameleons in natural habitats. In Bradypodion ventrale and thamnobates, there were no differences in body condition score between the different populations.

Research into exactly how these exciting differences come about is still pending.

Big cities, big bodies: urbanisation correlates with large body sizes and enhanced body condition in African dwarf chameleons (Genus: Bradypodion)
Jody M. Barends, Krystal A. Tolley
African Zoology 2024, 59(3)
DOI: 10.1080/15627020.2024.2402256

Photo: Bradypodion melanocephalum, photographed by suncana, licence Creative Commons Attribution 4.0 International

The new CHAMAELEO is out now!

The new CHAMAELEO is out now!

AG Interna Beobachtungen CHAMAELEO Haltungsberichte Science

Good things come to those who wait: we have just received the latest issues of CHAMAELEO 49. They will now go into the mail as soon as possible and will then be on their way to all AG members. The current contents can be found here. And if you are not yet a member of the AG Chameleons, you might want to become one soon! How do you like the current issue? Do you have any comments, wishes or criticism? Too thick, too thin, too much English, too little? ;) We look forward to your feedback!

Impact of agriculture on chameleons in Madagascar

Impact of agriculture on chameleons in Madagascar

Science

In Madagascar’s eastern highlands, farmland for rice fields is mainly obtained by slashing and burning primary forests or secondary vegetation. The rice fields are only used for one season. The following year the field is used for root vegetables. After just one harvest, the land lies fallow for up to five years before it is slash-and-burned again to grow rice again. Just five of these cycles can turn fertile land into degraded. In recent decades, fallow land has been cleared at ever shorter intervals. This practice has allowed invasive, non-native plant species to spread, while Malagasy plants that depend on primary forest have disappeared. Malagasy scientists have now investigated the impact of this form of agriculture on chameleons on the east coast of Madagascar.

The Ankeniheny-Zahamena rainforest corridor in the eastern highlands was used as the object of study. It runs along the east coast of Madagascar over an area of around 5000 km², some of which are only connected by very narrow forest fragments. A total of 44 sites were investigated during the rainy season, which were categorised into five habitat types: Ten sites with closed canopy rainforests, eight with tree fallows, eleven with shrub fallows, ten sites after at least five slash-and-burn cycles (degraded land) and five sites where reforestation was practised. The majority of chameleons were searched for, identified and measured at night along predefined transects (three to four parallel lines each 50 metres long).

A total of 15 chameleon species of the genera Brookesia, Furcifer and Calumma were found, although three species could not be precisely identified (as far as recognisable, these are animals from the Calumma nasutum/emelinae complex). Most chameleons favoured closed rainforest, whereas significantly fewer animals and species were found after slash-and-burn clearing. In forest areas with reforestation efforts, the number of chameleons was significantly higher than in degraded areas. Both emphasise the need to protect remaining rainforests as well as the relevance of reforestation in Madagascar.

Six species (including Calumma cf. vencesi, Brookesia superciliaris, Brookesia therezieni, Calumma parsonii) were clearly more sensitive to agriculture and can probably only survive to a very limited extent outside primary forest. Only three species were found on intensively farmed land, of which only Furcifer lateralis was most frequently found there.

Effects of shwidden agriculture on chameleon diversity and abundance in eastern tropical rainforest in Madagascar
Rodlis Raphali Andriantsimanarilafy, Joseph Christian Randrianantoandro, Josué Rakotoarioa, Alain Jean Victorien Rakotondrina, Ruth Kelly, Alison Cameron
Sustainability and biodiversity conservation 3(2): 99-118.
DOI: 10.5281/zenodo.13861065

Photo: Carpet chameleon at the edge of a rice field in Madagascar, photographed by Alex Negro

Communal egglaying in Furcifer minor

Communal egglaying in Furcifer minor

Science

In chameleons, there are only a few reports of females laying eggs in very close proximity to each other. Archaius tigris is even known to lay eggs together. Such an observation has now also been made in Madagascar, more precisely in the Itremo Massif in the southern highlands of the island.

In January this year, a female Furcifer minor was observed laying eggs in the forest of Antsirankambiaty. Shortly after the first female had finished laying her eggs, a second female only 30 cm away also started to lay eggs (see a video here). Two days later, a third Furcifer minor female laid her eggs between the two existing nests.

All three nests were dug into the sand of a riverbank about 2-3 metres from the water. The site was a rather sunny place with more than 5 hours of sunshine a day, so it might have been better suited for oviposition than the ground in the neighbouring forest fragment. However, it is also possible that the ongoing deforestation and thus the decreasing habitat is causing female Furcifer minor to look for oviposition sites outside their actual habitat. It is unclear whether the third female is one of the first two that returned – unfortunately it was not possible to differentiate between them.

Communal egg-laying in the Lesser Chameleon, Furcifer minor (Günther, 1879), at Itremo Massif Amoron’i Mania Region, Madagascar
Devin Edmonds
Herpetology Notes 17, 2024: 579-581
DOI: nicht vorhanden

Foto: Eines der Furcifer minor bei der Eiablage, fotografiert von Devin Edmonds

Karyograms of five Malagasy chameleons described

Karyograms of five Malagasy chameleons described

Science

It has been known for many years that the sex of chameleons is genetically determined. However, the karyograms of many species, i.e. the chromosome characteristics, are not yet known for all species. Italian scientists have now analysed the karyograms of five Madagascan chameleon species.

Existing, preserved chameleons were used for the study. One female each of the species Furcifer balteatus, Furcifer petteri, Furcifer major and Furcifer minor were sampled. One male and one female Brookesia superciliaris were also used for the study. All samples were subjected to DNA barcoding analysis using the mitochondrial gene fragment COI as a marker. The extracted DNA was amplified by PCR and then sequenced to create a karyogram for each animal.

The karyogram of Brookesia superciliaris is 2 n = 34 for both sexes. Of the 34 chromosomes, six are macrochromosome pairs and eleven are microchromosome pairs. All macrochromosomes are metacentric. Morphologically, the chromosomes do not differ from each other, so that it remains unclear which could be the sex chromosomes.

Furcifer balteatus has a very special karyogram, which actually fits better with those of the genera Brookesia and Palleon than with the genus Furcifer. The karyogram is 2n = 34, which is the highest number of chromosomes among the chameleons. Of the 34 chromosomes, six are macrochromosome pairs and eleven are microchromosome pairs. The former are all metacentric. There are no morphological differences between the chromosome pairs, so that the sex chromosome has not yet been determined.

The karyogram of Furcifer major is 2n = 24. Nine of the chromosome pairs are macrochromosome pairs and three are microchromosome pairs. Seven of the macrochromosome pairs are metacentric, only pairs two and three are submetacentric. The eleventh chromosome pair, a microchromosome pair, codes for the sex chromosome W.

Furcifer minor has a karyogram of 2n = 22 chromosomes. Of these, eight pairs are macrochromosome pairs and three are microchromosome pairs. Among the macrochromosomes, the first five pairs are metacentric, while the remaining three pairs are acrocentric. A portion of the sixth pair of chromosomes was almost completely heterochromatic and probably represents the sex chromosome W.

The karyogram of Furcifer petteri is also 2n = 22, of which eight pairs of chromosomes are macrochromosomes and three microchromosomes. Seven pairs of macrochromosomes are metacentric, only the fifth pair is submetacentric. The sex chromosome W is part of the seventh pair of macrochromosomes.

All newly described karyograms are deposited in GenBank under the number PQ272538-4. In this study, the genus Furcifer was also found to have the highest diversity in the karyograms. It also appears to be the only genus among all vertebrates that shows all variants of sex chromosome diversification.

New insights on Chromosome Diversification in Malagasy Chameleons
Marcello Mezzasalma, Gaetano Odierna, Rachele Macirella, Elvira Brunelli
Animals 2024, 14: 2818
DOI: 10.3390/ani14192818

Graphic: Karyograms of Brookesia superciliaris and Furcifer balteatus from the above-mentioned study

New distribution record for Kinyongia magomberae

New distribution record for Kinyongia magomberae

Verbreitung Science

Scientists from Tanzania and England recently carried out a survey study of the herpetofauna in the Kimboza forest. Kimboza is located in eastern Tanzania on the edge of the Eastern Arc Mountains, a 600 km long mountain range. To the west of Kimboza are the Uluguru Mountains, to the east the Ruvu Reserve. Kimboza is one of the smallest reserves in Tanzania with an area of only 4 km². It ranges in altitude from 170 to 480 metres.

To detect reptiles and amphibians, manual searches were carried out on two nights in December and January and for eleven consecutive months between December and June. In addition, bucket traps were placed in the ground along two lines, a total of between 11 and 20 buckets at a distance of 5 metres from each other. The animals found were identified morphologically using existing field guides. Samples were taken from 12 finds in order to genetically confirm the species identification.

A total of 42 different reptile species and 29 amphibian species were recorded in Kimboza. As expected, Trioceros melleri, Rieppeleon brevicaudatus and Chamaeleo dilepis were among the known chameleons of the forest. However, the study also revealed something astonishing: Kinyongia magomberae, actually known from the forest of Magombera and from the lowlands of the Udzungwa Mountains National Park, was found there. This corresponds to an extension of the distribution area of this species of 128 km. In a study from 1994, Kinyongia oxyrhina is already mentioned once in Kimboza. Even then it could have been a case of confusion and actually a Kinyongia magomberae. The species may have been much more widespread in the past than it is today. However, as the lowland rainforests of Tanzania have been extensively deforested for many decades, the chameleon’s habitat has been greatly reduced – and could have led to the spread of a species in forest areas that are no longer contiguous today.

Kimboza, a small lowland forest with an outstanding herpetofauna diversity in east Africa
John V. Lyakurwa, Simon P. Loader, Wilirk Ngalason, Rikki Gumbs, Caleb Ofori-Boateng, H. Christoph Liedtke
Nature Notes 14(10), 2024
DOI: 10.1002/ece3.70406

Picture: Kinyongia magomberae, photographed by Andrew R Marshall in Mwanihana forest, Creative Commons Attribution 3.0 Unported

Occurrence of the European chameleon in Tlemcen (Algeria)

Occurrence of the European chameleon in Tlemcen (Algeria)

Verbreitung Science

The 21.6 km² Tlemcen Hunting Reserve is located in the north of Algeria, in the province of the same name. The climate is Mediterranean, the province borders the Alborán Sea (the westernmost part of the Mediterranean Sea) and lies directly opposite south-east Spain. The reserve is located around 26 kilometres southwest of the city of Tlemcen, the second largest city in Algeria, and spans the highest areas of the Tlemcen Mountains.

A local veterinarian and biologist recently carried out a survey study of the animals currently found in the reserve. In order to investigate the herpetofauna, manual searches or traps were set along measured transects. Chamaeleo chamaeleon was found several times during the study.

Inventory of wildlife in the Tlemcen Hunting Reserve
Rafiq Rahmouni, Louiza Derouiche
Genetics and Biodiversity Journal 8(2), 2024
DOI: not available

Picture: Chamaeleo chameleon, photographed by Peter A. Mansfeld, licence Creative Commons Attribution 3.0 Unported

New modelling of species loss in Madagascar

New modelling of species loss in Madagascar

Verbreitung Science

For some time now, there have been various programmes and algorithms that can make various predictions about how many species in a country or region could be threatened with extinction in the future based on given data. Until now, this has always required a whole series of locations and data for the respective animal species as a basis. However, these are often not available for rare species.

Italian scientists have now developed an algorithm called ENphylo, which can make predictions from just two observations per species. It was tested in parallel to conventional algorithms on a model with 56 chameleon species from Madagascar. The occurrence and locations of the chameleons were taken from the Global Biodiversity Information Facility. Various scenarios of climate change and progressive changes in land use were modelled using CHELSA and other databases for the period between 2071 and 2100. For each of the chameleon species, 45 modelled predictions were calculated in the study.hnet.

As a result, the scientists predict a habitat loss of over 90% for the species Brookesia decaryi, Brookesia brunoi, Calumma globifer, Brookesia desperata, Brookesia karchei, Brookesia micra, Brookesia tristis, Calumma amber, Calumma guibei, Calumma ambreense, Calumma nasutum, Calumma fallax, Calumma peltierorum, Calumma boettgeri, Furcifer petteri and Furcifer willsii. As a result, these species would be directly threatened with extinction by 2100 due to climate change and changes in land use in Madagascar. The greatest area losses in potential habitats are expected in the dry forests of the west and north-west and the lowland rainforests of the east coast. The potential habitat loss is also expected to affect species that only occur in a very small distribution area but are very common there, such as Brookesia tuberculata.

An increasing development of the habitat is only assumed for Furcifer oustaleti, Furcifer rhinoceratus, Calumma parsonii (unfortunately without indication of the subspecies), Calumma oshaughnessyi, Calumma crypticum, Calumma brevicorne and Brookesia supericilaris. According to the various calculation models, Madagascar could lose between eight and eleven chameleon species by the year 2100.

Modelling reveals the effect of climate and land use change on Madagascar’s chameleons fauna
Alessandro Mondanaro, Mirko di Febbraro, Silvia Castiglione, Arianna Morena Belfiore, Girogia Girardi, Marina Melchionna, Carmela Serio, Antonella Esposito, Pasquale Raia
Communications Biology 7, 2024: 889
DOI: 10.1038/s42003-024-06597-5

 

Photo: Calumma crypticum in Ranomafana, Madagascar, photographed by Alex Laube