Friday, 17 December 2010

Rampant logging, illegal collection and slash and burn agriculture driving Madagascar’s rare frogs towards extinction

Amphibians in the mist: Madagascar's endemic frogs increasingly under threat

By Derek Schuurman and Franco Andreone

The frogs of Madagascar: A rich endemic biodiversity
Recently, some of the leading experts on the endemic herpetofauna of Madagascar estimated that the island possesses 450-500 species of amphibians, with many still awaiting formal classification. However, this stunning array of often remarkable and endemic amphibians is up against a catalogue of increasingly overwhelming threats. These are principally habitat loss due to inappropriate agricultural practices; forest degradation due to illegal logging; climate change, and the pet trade.

Illegal logging threatening the country and its wildlife
Since the democratically elected president was deposed and replaced by a transitional authority in 2009, illegal logging in Madagascar's protected north-eastern rainforests - many of which fall under the World Heritage Site of the Atsinanana Rainforests - has escalated to nightmarish proportions. The consequent degradation of these fragile, remote rainforests has placed the continued survival of any rainforest-dependent species sensitive to habitat disturbance, in jeopardy.

Protected rainforests most affected by the illegal logging activities include the national parks of Marojejy, Masoala and Mananara, and the Natural Park of Makira. In June 2010, the journal Madagascar Conservation & Development (MCD) published the most comprehensive analysis of Madagascar's illegal logging trade to date. Its Malagasy and Chinese authors outlined how the trade in illegally harvested precious timbers generated some $200 million for a small group of individuals over the past year. As the authors of the MCD journal article reported, illegal logging activities peak shortly before national elections and are probably a source of funds for political campaigns.

10,000 people living inside Masaola National Park
Any logging activities in legally protected areas are illegal, and such activities continue to take a heavy toll on the lowland rainforests of Madagascar in particular, with certain species now more at risk than ever. In November 2010, a team of field researchers from Missouri Botanical Garden, returned from a field expedition to Masoala National Park and reported the presence of approximately 10,000 people living inside the park and harvesting precious hardwoods.

Given the current state of affairs in Masoala National Park - which clearly indicates a lack of enforcement of the mentioned decree - coupled with constant reports from underground sources in northeast Madagascar describing rampant logging in Mananara and Makira protected areas - the situation appears bleak. It is difficult to say how severely this extensive logging can affect the wildlife, but it is clear that there will be negative impacts. Recent studies in the Atsinanana rainforests have also revealed that there are still many undescribed frog species which are classified as Data Deficient. Herpetological experts believe that some of these species have very narrow ranges, mostly limited to river systems, and that therefore damage wrought by logging may already have affected certain species heavily, possibly even leading to extinctions. We can confirm that some of these species are already extinct, and it is likely that future assessment based on genetic differentiation will unveil a worrying, hidden rate of extinction within the frogs of Madagascar.

Slash and burn and massive fire damage
For centuries, inappropriate traditional agricultural techniques or ‘tavy' (slash & burn) have been considered the major reason for habitat loss in Madagascar, and primarily the activity which has reduced Madagascar's diverse forest types to mere thumb-prints of their original extent. In November 2010 we received a report from a conservationist based in the SAVA region of north-east Madagascar (where most of the logging problems occurred throughout 2009), to the effect that there are so many forest fires, it has been impossible to see the sun for days. Frequently in the burning season (September to November), fires set by farmers to stimulate new growth of grass for their herds of Zebu cattle, spiral out of control and in many cases, these fires have caused severe habitat damage to officially protected areas.

6,000 hectares of Isalo National Park destroyed by fire
One such fire was reported by various sources in mid September 2010, as having destroyed 6,000 ha of the 81,000 ha Isalo National Park, a rugged sandstone massif in the country's semi-arid south-western interior.

Pet trade

Desolate and naturally parched as this massif may be, it supports some of the island's most interesting and localized amphibians, reptiles and plants. At the same site, Franco Andreone witnessed a fire in November 2009, while conducting a radio-tracking study on the remarkable rainbow frog (Scaphiophryne gottlebei), which due to its almost psychedelic appearance, is also a target of the pet trade. This species, together with the blue-legged mantilla (Mantella expectata) represents two of the most striking localised amphibians of the Isalo Massif.

Formerly known only from only a few breeding sites, they have both been found slightly more widespread. The influence of the fire on their survival and on their long-term conservation is not yet properly understood. It is hoped that their common habit of seeking refuge within deep fissures and in wet canyons of the massif can help them survive the regular, devastating fires.

Locally endemic
Other notable recent fires include the destruction of exotic pine forest on the Ankaratra Massif. This replanted forest provided some forest cover on the Ankaratra, one of the highest peaks in Madagascar. The massif is home to a select group of reptiles and frogs: two critically endangered frog species - Boophis williamsi and Mantidactylus pauliani - exist nowhere else. Now that most of the pine has been burned there will be serious consequences for the general habitat quality: with the forthcoming rains in the austral summer of 2010, the ground will be transformed into mud and this, together with ash, can pollute the montane streams severely.

Wildlife smuggling
Reports on incidents of reptile and amphibian smugglers being apprehended nowadays are commonplace, with many stories displayed on the internet and in daily newspapers. An example is that of a South African zoology student from Pretoria, who was caught trying to smuggle 388 reptiles and frogs - including such sought-after species such as Uroplatus leaf-tailed geckoes, in the lining of his jacket. In July 2010, TRAFFIC reported the discovery of hundreds of endemic Malagasy tortoises, for which two women were arrested. According to the report, the women were sentenced to a year in prison under Section 10 (a) of the International Trade in Endangered Species Act 2008.

TRAFFIC added that they were the first people to be prosecuted under the Act which came into force on 28 June. The women had filled two bags with 369 Madagascar radiated tortoises, 5 critically endangered Ploughshare tortoises and also 47 Tomato frogs and numerous chamleons. TRAFFIC noted that this was the second instance in just over a month involving smuggling of rare Malagasy reptiles into Malaysia, because in June 2010, customs officers in Kuala Lumpur International Airport discovered 285 Madagascar radiated tortoises, 14 Spider tortoises (Pyxis arachnoides) and a single Ploughshare tortoise, in two unclaimed suitcases.

Although the impact of collecting for the pet trade (either legal or illegal) is still a matter of debate, it cannot be denied that, especially in heavily degraded situations, this activity represents a threat as it is the case with the extremely rare harlequin mantella (Mantella cowani), known from a few sites in the highlands, and which was until a few years ago collected in high numbers.

Fortunately a commercial ban implemented in 2003 and the creation of a protected site, represent a glimmer of hope for the species' long-term survival.

Frog fungus - Not yet
Amazingly, Madagascar has not yet been affected by the lethal killer fungus Batrachochytrium dendrobatidis which has caused local and global extinctions of amphibian species, and population crashes around the world. Or, at least, this is a result revealed after a spate of research carried out by the South African specialist C. Weldon and colleagues, and also independently by A. Crottini and M. Casiraghi (at Itremo Massif). All these studies, conducted using both histopathological and molecular methods, revealed negative results. However, taking into consideration what has happened elsewhere around the globe, there is always the possibility that this pathology could arrive in Madagascar - either with trade of infected animals, plants and materials - or via boots and equipment used by eco-tourists and scientists.

Madagascar therefore, is in a uniquely privileged position to act as a laboratory for counteracting the Bd introduction. In April and October 2010 workshops were carried out respectively at Antananarivo and Ivoloina (Toamasina) and a specific action plan was created, together with the constitution of an "emergency cell" composed by foreign and national experts. The "emergency cell" will take decisions regarding the actions necessary in case the chytrid alarm is sounded. In the meantime, it will coordinate a monitoring program, that involves 8 sites in Madagascar (chosen within a series of rainforest, dry forest and a high plateau site), and for which two species will be sampled twice a year to get a 50 + 50 annual sample.

These samples will be analysed for the presence of the Bd. At the same time, a program of captive breeding is being launched, with the aim of acquiring the knowledge of basic husbandry science, as this will be useful in case an infected species or population needs to be removed from its natural sites.

Comparatively little is known on the captive husbandry of most of the 270 described species of Malagasy frogs. Only a few species, like mantellas and some microhylids (Dyscophus) have been studied in captivity. Of the rest, virtually nothing is known, so there is an urgency to develop these skills and increase the knowledge in Madagascar and abroad.

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