Category Archives: amphibians

THE RACE: Homage to “The Prince”

The island of Príncipe is ancient… at 31 million years of age it is twice as old as São Tomé, yet biologically the two islands are unquestionably related. Along with documenting and describing hitherto unknown species of strange, endemic plants and animals that inhabit one or the other island (rarely, both), we attempt to understand the relationships of these species to each other and to their ancestral populations from the African mainland.

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For instance among the striking Príncipe uniques is Leptopelis palmatus, the Príncipe giant tree frog (above). Females of this species attain dimensions such that they are largest tree frog in Africa! Males, first described by us, are usually less than half their length. The original specimen upon which the species description was based over a century ago was a single female of 110mm body length (excluding legs). Like all female frogs, they do not have an advertisement call and despite their great size, very few have been found and reported in the scientific literature.

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(male)

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(female)

A few days ago, Dr. Rayna Bell found the large female pictured above, pressed to the surface of a small flat rock on the ground on a steep, dryish slope in the northwestern part of the island. Females tend to be dark compared to males, but this is the first all-black specimen reported. There are three other tree frog species on the islands, but they are all closely related to each other and belong to a different frog family from the Príncipe giant.

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Dr Bell has shown that these other three are most closely related to a species from the Ogooué and Congo River basins and thus likely of western Central African origin. Other work has shown that the nearest relative of Leptopelis palmatus of Príncipe is from west of the Niger River and thus the giant is  probably of northern (West African) origin, perhaps dispersing from the Niger River drainage..

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Dr. Luis Mendes and Maria Jeronimo have continued to collect butterflies to fill in knowledge gaps with species for Luis’s book. Luis has collected a number of specimens that he cannot readily identify; on these poorly-known islands, this is particularly exciting.

Maria has actually been doing a lot of everything: collecting butterflies with Luis, joining us in the classrooms and going out at night collecting with Dr. Rayna Bell, Lauren Scheinberg and our photographer, Andrew Stanbridge. Considering that this is a “break” from her PhD dissertation work, her energy level is truly impressive.

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Most geckos are nocturnal but the genus Lygodactylus is comprised of strictly daytime species in Africa and Madagascar. Readers may recall that the islands of Annobon, São Tomé and Príncipe are each inhabited by a single endemic species usually distinguishable by different black markings under the chin; other than these markings, the island species are usually a combination of grey and black. Luis Mendes captured an adult male on Príncipe that appears to be in breeding coloration of a sort I have not seen before in this genus. There is one species endemic to a small forest in Tanzania that is a beautiful blue, several others in East Africa that have yellow heads, and one species in Zambia that has a yellow belly. The male collected on Principe has a bright yellow head and the body that is a striking shade of light green. Not only is this the first time I have observed a green individual, I am also unaware of any literature describing temporary (usually hormonal) color intensities associated with breeding activities in this group of lizards.

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Many of the photos we post on social media might well suggest that our work is being carried out in some sort of paradise; in some ways it is exactly that but is by no means easy!

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The work we do here is only possible with the support of local entities; this is especially true on Príncipe. On our first two expeditions years ago we had difficulty finding suitable accommodations (reliable power for our equipment, etc) and logistics; there were not many available vehicles on the island, and we had little access to the really interesting higher elevation areas of the island or more remote southern areas. Since that time, our efficiency has increased hugely due to the generous support of several organizations on the old island. First and foremost is the Office of the Regional President (Tose Cassandra-he is also head of the recently created Principe World Biosphere Reserve, and also Daniel Ramos, head of the Príncipe Obo Natural Park.

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For a number of years, we have been able to stay at Bom Bom Island resort which has also helped with needed transportation, both vehicular and marine. This year we were invited to stay at the new Roça Belo Monte (Africa’s Eden) who also provided transportation and assistance. At one point we planned a boat trip to explore the remote southeastern part of the island but the skipper, Bobby Bronkhorst, of Makaira Lodge fell ill.

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Our work is now also in cooperation with the newly formed Príncipe Trust; the Trust played a major supporting role in the production of this year’s biodiversity bird field guide/coloring book and binoculars! Our biodiversity education efforts were concluded for Gulf of Guinea IX here on the old island with our return to the 3rd grade classes of the same schools we have been visiting since 2011. Usually after class visits, we see 3rd graders out in the bush peering through their new binoculars but frequently backwards! This may well be more fun for them.

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Parting Shot:
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PARTNERS:
We are most grateful to Arlindo de Ceita Carvalho, Director General, Victor Bomfim, and Salvador Sousa Pontes of the Ministry of Environment, Republic of São Tomé and Príncipe for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tomehttp://www.stepup.st/, our “home away from home”.We gratefully acknowledge the support of the G. Lindsay Field Research Fund, Hagey Research Venture Fund of the California Academy of Sciences for largely funding our initial two expeditions (GG I, II). The Société de Conservation et Développement (SCD) and Africa’s Eden provided logistics, ground transportation and lodging (GG III-V), and special thanks for the generosity of private individuals who made the GG III-VII expeditions possible: George G. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke, Mr. and Mrs. Michael Murakami, Hon. Richard C. Livermore, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. Robert M. Taylor, Velma and Michael Schnoll, and Sheila Farr Nielsen; GG VI supporters include Bom Bom Island and the Omali Lodge for logistics and lodging, The Herbst Foundation, The “Blackhawk Gang,” the Docent Council of the California Academy of Sciences in honor of Kathleen Lilienthal, Bernard S. Schulte, Corinne W. Abel, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. John Sears, John S. Livermore and Elton Welke. GG VIII was funded by a very generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Mrs. W.H.V.“D.A.” Brooke, Thomas B. Livermore, Rod C. M. Hall, Timothy M. Muller, Prof. and Mrs. Evan C. Evans, Mr. and Mrs. John L. Sullivan Jr., Clarence G. Donahue, Mr. and Mrs. John Sears, and a heartening number of “Coolies”, “Blackhawk Gang” returnees and members of the Academy Docent Council. Once again we are deeply grateful for the support of the Omali Lodge (São Tomé) and Roça Belo Monte (Príncipe) for both logistics and lodging and for partially sponsoring part our education efforts for GG VII and GG VIII.

Our expeditions can be supported by tax-deductable donations to “California Academy of Sciences Gulf of Guinea Fund

THE RACE: GG IX – RETURN TO THE BIG ISLAND

The seven members of GG IX all met up in the Lisbon airport on September 18 and arrived the next day in São Tomé. Two new collegues on this expedition are from Portugal. Dr. Luis Mendes, a butterfly expert from the Natural History Museum in Lisbon is finishing a major book on the butterflies of the islands and is checking certain localities for species that have not been seen for many years.

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Maria Adelina Jeronimo, a PhD candidate from the Gulbenkian Institute in Portugal, also studies butterflies but specifically the genetics of certain novel morphological characters. Maria is a matter of months from finishing her doctoral dissertation.

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Dr. Rayna Bell has returned for her third trip and is continuing her studies of the interesting hybridization phenomenon that seems to be occurring between the two endemic São Tomé tree frog species, reported in a major publication earlier this year. She has also discovered that the little green tree frogs of Principe, while seemingly nearly identical to those of São Tomé, are in fact a separate species. This does not surprise us really; see earlier blogs on geckos and snakes!

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Rayna is being assisted by our third new member,  Lauren Scheinberg of the Herpetology Department of the California Academy of Sciences.

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Our brilliant (and very tall) photographer, Andrew Stanbridge, has joined us for the fifth time (also as co-leader).

The education team is, as usual, Roberta Ayers and myself, plus our long-time São Toméan colleagues, Roberta dos Santos, Anita Rodriguez and Quintino Quade Cabral. Maria Jeronimo has been assisting. A new cycle begins this year, starting again with third grade.

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There have been several interesting discoveries already. A couple of years ago we published a study of the giant geckos of the islands, describing a new species from Príncipe (Miller, et al, 2012). We suggested that the large endemic species of São Tomé, Hemidactylus greefi, was only found in natural settings, having been out-competed in the towns by common, widespread recent colonizers. During our first week the group found an adult Greef’s gecko at sea level on a door in Angolares, the second largest town on the big island. I suspect that if competition with widespread common immigrants accounts for the absence of this gecko in the capitol city, there must be fewer of the former in Angolares. This is understandable as Angolares is still quite small and is not by any means a port city; that has always been São Tomé city.

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As in every year, we went to the Olea tree at Macambrara (1100 m) to check on the known population of the giant São Tomé tree frog, Hyperolius thomensis. Long-time readers will recall that two holes in this enormous tree are the only place we have consistently found this colorful species. While we have conjectured that the giant tree frog must be widespread in the higher elevation forests (we can hear it call from far above in the canopy), we have been unable to find another locality or tree with appropriate breeding holes… until now!

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With our colleague, Dr. Ricardo Lima of University of Lisbon, we were able to gain access to the primary forest above the huge southern oil palm plantation of Agripalma. At 350 m, above an abandoned roça called Monte Carmo, Bell, Scheinberg, Lima and Stanbridge found large numbers of the giant São Tomé tree frog breeding in pockets of water on fallen logs. This southern-most locality indicates, as we suspected, that this flamboyant frog is widespread in the relatively undisturbed forest and that while not restricted to high elevation (Macambrara), it does indeed seem to breed in pockets of water such as tree holes, rather than standing water like its close relative.

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Here, there appears to be no hybridization as the two tree frog species are separated by oil palm rather than less biologically hostile agricultural fields or plots. In fact, so far as I know, hardly any endemic vertebrates or native plants are able to survive in oil palm.

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This area is also the last bastion of a remarkable endemic bird, the Dwarf ibis, the smallest species of ibis in the world; it is severely threatened, both by hunting and by habitat destruction (oil palm). Notably, there are now two charismatic endemic species, a bird and a frog, endangered by human activities on this remote and fascinating island.

So far, this year’s activities have included working in a number of new localities including the central massif and in the far south. High in the mountains above Roça Agua Izé, one of the larger of the coastal colonial cacao plantations, we got our first decent view of a Giant weaver, Ploceus grandis. One of many endemic island giants on São Tomé and Príncipe, this colorful weaver is the largest in the world.

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As always, our educational efforts are aimed at raising the children’s awareness of the unique aspects of the island flora and fauna. We do not preach conservation per se. but rather try to show the young students how special their islands are and thus how special they are as owners.

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This year, each third-grader gets our coloring book about endemic bird species on both islands, a box of colored pencils and a pair of plastic binoculars (which work!!) These are not just handed out…. we present them personally to each student in each classroom, along with enthusiastic instructions for use, and the reasons  we come each year; we involve the students, the teachers, even school principals, and it is great fun. At the end, 10 of our stick-on logo patches are given to the teacher to reward good work. Each of us is involved at one time or another, as voices begin to suffer after 3 or 4 classroom visits.

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At this point, I must mention some wonderful folks who have been vital to the education effort this year: Alice and Wayne Settle conceived of and sponsored the acquisition of the small binoculars; Jim Boyer of the California Academy of Science once again produced a booklet that qualifies as a work of art, and help with producing the bird books is coming from the Príncipe Trust.

In the next blog, I will report on our progress on the smaller geologically ancient island of Príncipe.

Meantime, here’s the parting shot:

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All photos by Andrew Stanbridge

 

 PARTNERS:
We are most grateful to Arlindo de Ceita Carvalho, Director General, Victor Bomfim, and Salvador Sousa Pontes of the Ministry of Environment, Republic of São Tomé and Príncipe for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tomehttp://www.stepup.st/, our “home away from home”.We gratefully acknowledge the support of the G. Lindsay Field Research Fund, Hagey Research Venture Fund of the California Academy of Sciences for largely funding our initial two expeditions (GG I, II). The Société de Conservation et Développement (SCD) and Africa’s Eden provided logistics, ground transportation and lodging (GG III-V), and special thanks for the generosity of private individuals who made the GG III-VII expeditions possible: George G. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke, Mr. and Mrs. Michael Murakami, Hon. Richard C. Livermore, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. Robert M. Taylor, Velma and Michael Schnoll, and Sheila Farr Nielsen; GG VI supporters include Bom Bom Island and the Omali Lodge for logistics and lodging, The Herbst Foundation, The “Blackhawk Gang,” the Docent Council of the California Academy of Sciences in honor of Kathleen Lilienthal, Bernard S. Schulte, Corinne W. Abel, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. John Sears, John S. Livermore and Elton Welke. GG VIII was funded by a very generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Mrs. W.H.V.“D.A.” Brooke, Thomas B. Livermore, Rod C. M. Hall, Timothy M. Muller, Prof. and Mrs. Evan C. Evans, Mr. and Mrs. John L. Sullivan Jr., Clarence G. Donahue, Mr. and Mrs. John Sears, and a heartening number of “Coolies”, “Blackhawk Gang” returnees and members of the Academy Docent Council. Once again we are deeply grateful for the support of the Omali Lodge (São Tomé) and Roça Belo Monte (Príncipe) for both logistics and lodging and for partially sponsoring part our education efforts for GG VII and GG VIII.

Our expeditions can be supported by tax-deductable donations to “California Academy of Sciences Gulf of Guinea Fund

The RACE: SIZE MATTERS!

It is a fundamental tenet of the science of island biogeography that more different species of plants and animals will be found on larger islands than on smaller ones. When we say “larger” in this regard, we really mean surface area. Note that in the graphic illustration below right, both islands have the exactly the same circumference, but the lower island has a mountain in the middle of it which markedly increases any measure of its overall surface area.

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RCD construct.

The greater (and more varied) the surface area, the larger the number of niches for living organisms; hence with time and evolution there will be more living plants on animals on larger islands than smaller (above left). For “niches”, think of “jobs”; every living thing has a three-part job: 1. where it does what it does (spatial niche); when it does what it does (temporal niche) and how it gets its energy (trophic niche). No two living things can overlap on all three and coexist, hence size (area) matters! There are other factors of course, such as geological age and island distance from source, that affect the numbers and characteristics of species found on islands.

Our islands of São Tomé and Príncipe are classic examples of the area/species number relationship. Here are just a few examples:

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Begonia thomeana. T. Daniel phot. — GG

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African butterfly. Photo from  ARKives. Google Images

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New tree frog (Hyperolius) species from Principe Id. A. Stanbridge phot– GG VII.

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African dragonfly.  ARKive phot. Google Images.

The island area effect is even more convincing when the entire archipelago of four islands is included, from the largest (Bioko) to the smallest (Annobón).

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 Lacewing distribution in Gulf of Guinea. Dong Lin phot. GG I; RCD construct.

As one can see, there is an obvious correlation between island size and the number of lacewings present; however in this case it is also important to note that while Bioko is clearly the largest island, it is also geologically youngest and closest to the mainland, having been attached to the mainland multiple times during the Pleistocene. Such factors can have an important effect on these comparisons. While these correlations prove correct over and over again. However this does not mean that very small islands cannot house wonderful biological surprises, and we are learning that this is true in the Gulf of Guinea.

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Jockey’s Bonnet. A. Stanbridge phot, GG VII

Above is the Jockey’s Bonnet (or Ilha Caroço) so named for its obvious shape. This large rock is only about 3.5 km off the southeast shore of Príncipe, only 35 hectares in area but perhaps 100 m in height. It was undoubtedly once part of the main island, which readers will recall dates back to the Oligocene Epoch, so it is probably quite old geologically.

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Jockey’s Bonnet. A. Stanbridge phot. GG VII

Although small, the Jockey’s Bonnet houses at least two very intriguing species. The population of native oil palms (Elaeis guineensis) on the western shores of this tiny island have obviously been there for a long time as they have begun to accumulate change from the parent species on the main Island, but a few km away! While still clearly the same species, the Jockey’s Bonnet palms bear seeds (fruit) that is at least twice the size of the palms on Príncipe and São Tomé.

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Bonnet oil palm seed. RCD phot. CAS botany specimen

For bird lovers, an even more exciting occurrence on the Jockey’s Bonnet is that of the Bonnet Seed-eater, a small brown passerine bird noticeably different from its relatives only a few kilometers away on Príncipe!

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Bonnet seed-eater. A. Stanbridge phot. GG VII

These unique birds are heavier, have longer, broader bills and shorter wings than their island neighbors and have been shown to be genetically distinct from them. They are extremely common (some 3,500 individuals at last estimate) and live exclusively in the oil palm forest pictured above. They have a specialized diet of palm oil and palm pollen, and it is tempting to speculate that there might be some relationship driving the evolution of the palms and the birds.

Isolation and evolutionary change within a population of birds separated from their nearest relatives by only 3 km may well seem counter-intuitive; after all, don’t birds fly? The answer is yes they do, but they don’t need to, they often don’t, at least not long distances! Flying is energetically expensive; if the habitat is relatively stable, suitable for survival and reproduction, why leave it? In spite of their ability to fly, most bird species tend to remain in specific kinds of habitats and areas. This is called philopatry.

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Tinhosa Grande.  A. Stanbridge phot. VII

Far to the south of Príncipe (ca. 20 km.) is a fascinating group of small islands known as the Tinhosas. The largest of these is Tinhosa grande (above) with a surface area of but 20.5 ha.

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RCD construct

Geologically the Tinhosas are of great interest because they mark the southernmost limit of the Oligocene Príncipe of over 31 million years ago. As we have noted in earlier blogs, Príncipe was once much, much larger but through millions of years of weathering, largely from the southwest, all that remains are the Tinhosas and Príncipe, along with its other islets. And again, Principe is twice as old as São Tomé.

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RCD phots, GG I and II  (right – bridled tern)

The Tinhosas are important rookeries for some sea birds such as Brown and Black Noddys, the Sooty Tern and Brown Booby and are recognized by Birdlife International as Wetlands of International Importance and official Waterfowl Habitat.

Tinhosa Grande is also inhabited by at least two different kinds of lizards, a skink species and a gecko species. These were observed and photographed by members of a recent ornithological expedition but specimens were not collected. Our colleague, Dr. Luis Ceriaco, of the Natural History Museum in Lisbon discovered that some of these skinks had been collected by a Portuguese expedition and deposited in that museum 45 years ago.

CeriacoDr. Luis Ceriaco with Principe giant tree frog..  phot from Facebook.

After analysis, Luis discovered that the Tinhosa Grande specimens represented a new species which he has described as Trachylepis adamastor. It is a very large skink differing from its nearest relatives in size, scales and coloration.

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Tinhosa skink. (Trachylepis). Ross Wanless phot.

Members of the more recent bird expedition reported to Ceriaco that that the population of these skinks seemed very dense, and Ceriaco later speculated that there might be a trophic relationship between the numerous skinks and the nesting birds. Notice above that the skink is feeding on a recently broken egg (this photo appeared in the paper by L. Cericaco). Such relationships are not unknown.

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Cousin Island. Google images; bridled tern RCD image, Cousin habitat RCD image; Mabuya wrighti James Warwick image)

Cousin Island of the Seychelles Archipelago in the Indian Ocean exhibits a strikingly similar situation that has been well-studied. This small island of 27 hectares supports enormous populations of two species of skinks: Mabuya wrighti, which is large, and Mabuya seychellensis, which is smaller. Studies revealed that in 1979 there were approximately 1,713 individual skinks per hectare, and that these were supported directly by nesting terns (60,000 pairs of Lesser Noddy terns alone) through broken eggs, feces and dropped fish. Such a situation may well exist on Tinhosa Grande.

The Tinhosa gecko remains a mystery. We have no examples of it and cannot examine its morphology or molecular relationships.

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Tinhosa gecko. (Hemidactylus sp.) Photos by Nuno Barros, courtesy, Birdlife Int.

The photos are not of sufficient quality to determine whether this gecko is related to one of the unique island species (H. principensis, H. greeffii) or is a more widespread species.

We are preparing for GG IX in September. More anon.

The parting shot:

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A 4th grade Sao Tomean student with our biodiversity playing cards. A. Stanbridge phot. GG VII

 PARTNERS:
We are most grateful to Arlindo de Ceita Carvalho, Director General, Victor Bomfim, and Salvador Sousa Pontes of the Ministry of Environment, Republic of São Tomé and Príncipe for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tomehttp://www.stepup.st/, our “home away from home”.We gratefully acknowledge the support of the G. Lindsay Field Research Fund, Hagey Research Venture Fund of the California Academy of Sciences for largely funding our initial two expeditions (GG I, II). The Société de Conservation et Développement (SCD) and Africa’s Eden provided logistics, ground transportation and lodging (GG III-V), and special thanks for the generosity of private individuals who made the GG III-VII expeditions possible: George G. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke, Mr. and Mrs. Michael Murakami, Hon. Richard C. Livermore, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. Robert M. Taylor, Velma and Michael Schnoll, and Sheila Farr Nielsen; GG VI supporters include Bom Bom Island and the Omali Lodge for logistics and lodging, The Herbst Foundation, The “Blackhawk Gang,” the Docent Council of the California Academy of Sciences in honor of Kathleen Lilienthal, Bernard S. Schulte, Corinne W. Abel, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. John Sears, John S. Livermore and Elton Welke. GG VIII was funded by a very generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Mrs. W.H.V.“D.A.” Brooke, Thomas B. Livermore, Rod C. M. Hall, Timothy M. Muller, Prof. and Mrs. Evan C. Evans, Mr. and Mrs. John L. Sullivan Jr., Clarence G. Donahue, Mr. and Mrs. John Sears, and a heartening number of “Coolies”, “Blackhawk Gang” returnees and members of the Academy Docent Council. Once again we are deeply grateful for the support of the Omali Lodge (São Tomé) and Bom Bom Island (Príncipe) for both logistics and lodging and for partially sponsoring part our education efforts for GG VII and GG VIII.

Our expeditions can be supported by tax-deductable donations to “California Academy of Sciences Gulf of Guinea Fund

 













The Race: The Amphibians of Sao Tome and Principe, and the Expeditionion

The Biodiversity Education team has been hard at work on our product for GG VIII, of April, 2014.  The 2000 students we have been visiting since the 3rd grade are now in the 5th grade and will be moving on next year, so this is our last visit with them.  We have produced a slightly more technical biodiversity booklet (livreto) for each of them. This cohort represents slightly more than 35% of the island studentsin their age group.

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 NOSSAS PLANTAS  E ANIMAIS ESPECIAIS

2014 BioTeam

The Bio-education team in my Lab: Roberta Ayers (senior educator, and translation – on Skype), Velma Schnoll (Project Manager), Lindzy Bivings (education advisor),Jim Boyer (art work and layout), Tom Daniel (science text).Absent: Mike Murakami (graphics), me..

Just recently a great new book was published called The Monkey’s Journey, by Alan de Queiroz.  An entire chapter (6) is based on our hypothesis as to how amphibians and many of the other unexpected, endemic animals originally crossed over to the islands from the mainland.

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One of us has made an exciting discovery recently (see below) which prompts me to reacquaint readers with the amazing amphibian fauna of Sâo Tomé and Príncipe.  As readers already know, there should not be any amphibians on these islands at all;  they are true oceanic islands which have never been attached to the African mainland, and amphibians have no tolerance for saltwater. There are no native amphibians on the Galapagos or the Hawaiian Islands for this reason. Yet, there are seven species on our islands, possibly eight – all unique and found nowhere else in the world!  The most unlikely of these is the famous “Cobra bobo” of Sâo Tomé.

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Cobra Bobo in the hands of Quintino Quade of Sao Tome. D. Lin phot – GG I

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Upper left, unknown phot, upper right, RCD GGI, lower, R. A. Nussbaum

The cobra bobo (Schistometopum thomense) is a caecilian, part of a group of amphibians only distantly related to frogs and salamanders. They are found almost exclusively in the Old and New World Tropics. About 25% of the 200 species lay eggs, the rest, including our cobra bobo give birth to living young (see above).

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Although they look very much like earthworms, caecilians have backbones, teeth and a vertebral columns. (above lef-UCL photot). Most are burrowers although some are aquatic, but all caecilians lack legs, tails and have reduced eyes, and they are the only amphibians that have sensory tentacles located on each side of the head, between the nostril and the eye (above right – different species-J. Measey phot.).  These are protruded to sense prey items and the environment.

The cobra bobo is widespread under moist leaf litter, old banana stems, etc from sea level to as high as 1400m, at Lagoa Amelia. Although they are totally harmless, they are widely feared by the islanders, which is the reason we use a cobra bobo cartoon for our expedition logo (see earlier posts). We are attempting to demystify it. One of the most interesting things about this endemic species is the distribution of its closest relative.

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Note that several thousand km separate the two known species; the red ? indicates a single old specimen in Brussels from the Ituri region of Zaire that might also be a member of the same genus.

A frog unique to Sâo Tomé is Newton’s rocket frog, Ptychadena newtoni. There are over 50 species recognized on the African mainland, but this endemic is by far the largest of the genus, with females attaining lengths of over 60mm. This qualifies Newton’s rocket frog as a true “island giant.”

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Newton’s rocket frog. above phot RCD- GGI, below A. Stanbridge,-GGVI

Early records suggested it is a frog of streams and rivers in the northern lower elevations, but we have found its larvae as high as Java, at 600m, and in recent years, Hugualay Maya of ABS has discovered the species in river drainages farther south down the west coast. (pink markers).

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Known localities for Newton’s rocket frog. RCD construct

Frog larvae (or tadpoles as they are often known in English) are used in identification of species by scientists, as well as the study of adults and are formally described.

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Ptychadena newtoni.  above, whole larva; below are mouthparts] drawings -Dylan Kargas.

An extremely interesting fact about Newton’s rocket frog is the location of its closest relatives.  Like the cobra bobo, the species of Ptychadena genetically closest to our island frog are eastern species, not Central or West African.

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This study included 108 rocket frog samples from all over sub-Saharan Africa, including the Nile drainage, Madagascar and the Seychelles.

Another endemic island giant is Príncipe’s giant treefrog, Leptopelis palmatus. In fact, the first specimen ever collected and described nearly 150 years ago was a female measuring 110mm from snout to between the legs. This is the largest ever recorded for the genus.  The largest specimen we have collected was a 108mm female, during GG I near Sundi.

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Sundi female of 108mm. D. Lin phot-GG I

big lepto and male

Left:  same female, R Stoelting phot. GG I; right: Pico Papagaio male, just after calling.  Weckerphoto GG III

There are a number of strange things about this species; the females are usually always dark to dull green, while the males come in a great range of color patterns, some quite bright (polychromatic- see below). Moreover, the largest males are usually less than half the size of the females (above and below).  While we were the first to record its call, this is the one species on both islands for which we have no data for eggs or larvae. Most large females have been found in the lowlands of Príncipe, while males seem to be common up to 700m on the Pico.

polychromatism

Three males and a juvenile Principe giant tree frog.  J. Ledford phot- GG I

lepto nearest

Distribution of the Príncipe giant tree frog and its closest mainland relative, L. macrotis.  This may suggest that the ancestor of both rafted from the Niger River delta into the Gulf of Guinea.

Both islands have small species of puddle frog, Phrynobatrachus, that are widely distributed on both islands in leaf litter, and breed in temporary puddles of water. Both island forms were thought to be the same species (they are tiny and remarkably similar to the untrained eye) until we discovered that they were genetically quite distinct species with physical differences.

dispar principe

The Príncipe puddle frog, Phrynobatrachus dispar, can be found in wet areas from sea level to the top of Pico do Príncipe. While we have its larvae and eggs, we have not yet described them. D. Lin phots-GG II.

leveleve comp

The Sao Tome puddle frog, Phrynobatrachus leveleve  is very similar in appearance to the Príncipe species but there are great genetic differences and physical differences as well.  Like its relative on Príncipe, it is broadly distributed in wet areas from sea level to very high elevations. RCD phots, GG VI.

Its larval characteristics can be seen below.

leveleveX

Drawings: Dylan Kargas

Like the other amphibians, the distribution of the nearest relatives of our two island puddle frogs is intriguing.

phryno phylo

According to a recent study, Príncipe’s puddle frog, P. dispar is most closely related to a population in the Caprivi Strip of Namibia, and together their nearest relative is P. leveleve of Sâo Tomé. The interesting thing to notice is that all of the other members of this lineage, called a clade and defined by the purple box, are East African species.  This is reminiscent of the rocket frog and cobra bobo distributions.

Returning to island giants, we have the Sâo Tomé giant treefrog, Hyperolius thomensis. There are well over 200 species of this genus known from the African mainland, and females of this Sâo Tomé endemic are by far the largest at just under 50mm.

thom adult 2

D. Lin phot- GG I

thom adult1

D.Lin phot. GG – I

thom amplexus

Breeding pair of Sao Tome giant treefrog. D. Lin phot, GG II

This large flamboyant tree frog appears to largely be a tree canopy dweller.  We have discovered that eggs are laid in water-filled holes in trees (phytotelmata). They can be heard calling from treetops but are extremely difficult to locate; in fact all of our specimens have come from a single locality at around 1100m; we monitor this locality every year and keep its exact location a secret.  We have described the larval characteristics, below.

Hyperolius thomensis tads

Drawings by Dylan Kargas

Our last endemic species is closely related to the Sâo Tomé giant tree frog, although it is much smaller and not so brightly colored: Hyperolius molleri, the oceanic tree frog. Since our work began, it is the only remaining amphibian that has been thought to inhabit both Sâo Tomé and Príncipe.  In fact, years ago an early intern of mine, Katie Marshall, compared the two populations using mitochondrial genes and found no significant differences between them; they are certainly extremely similar morphologically ( see below).

2 molleris

Above, Weckerphoto GG III; below, RCD phot GG I

Recent work by Rayna Bell, our Cornell colleague (GG VI, VII) included a reanalysis of the two populations with more advanced technology, and indications are that the two populations may be quite distinct genetically. If this turns out to be the case, the Príncipe population will require much closer morphological examination and redescription, bringing the total number of endemic amphibians on our islands to eight!

While this small green tree frog appears to be a lower elevation dweller on Príncipe, on Sâo Tomé it reaches at least 1400m and can be heard calling at Lagoa Amelia. Like most other members of the genus, eggs are laid on leaves above water, the developing tadpoles ultimately wiggling out of the jelly mass and falling into the water for further development.  We have studied the larvae of the big island form (the original Hyperolius molleri- the species was described based on a specimen from that island) and the characteristics are below.

Hyperolius molleri ST

Drawings by Dylan Kargas

The team leaves for the islands in early April; our mission for GG VIII will largely be on biodiversity education as I mentioned in the beginning, but we will continue to post on our progress while there.

Until then, here is the parting shot:

b-b kingfisher Bronkhorst

The brilliant Blue-breasted kingfisher of Principe Island.  Photo by Michael “Bobby” Bronkhorst, 2014

PARTNERS
We are most grateful to Arlindo de Ceita Carvalho, Director General, Victor Bomfim, and Salvador Sousa Pontes of the Ministry of Environment, Republic of São Tomé and Príncipe for their continuing authorization to collect and export specimens for study, and to Ned Seligman, Roberta dos Santos and Quintino Quade of STePUP of Sao Tomehttp://www.stepup.st/, our “home away from home”. We gratefully acknowledge the support of the G. Lindsay Field Research Fund, Hagey Research Venture Fund of the California Academy of Sciences for largely funding our initial two expeditions (GG I, II). The Société de Conservation et Développement (SCD) and Africa’s Eden provided logistics, ground transportation and lodging (GG III-V), and special thanks for the generosity of private individuals who made the GG III-V expeditions possible: George G. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke, Mr. and Mrs. Michael Murakami, Hon. Richard C. Livermore, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. Robert M. Taylor, Velma and Michael Schnoll, and Sheila Farr Nielsen; GG VI supporters include Bom Bom Island and the Omali Lodge for logistics and lodging, The Herbst Foundation, The “Blackhawk Gang,” the Docent Council of the California Academy of Sciences in honor of Kathleen Lilienthal, Bernard S. Schulte, Corinne W. Abel, Prof. & Mrs. Evan C. Evans III, Mr. and Mrs. John Sears, John S. Livermore and Elton Welke. GG VII was funded by a very generous grant from The William K. Bowes Jr. Foundation, and substantial donations from Mrs. W.H.V.“D.A.” Brooke, Thomas B. Livermore, Rod C. M. Hall, Timothy M. Muller, Prof. and Mrs. Evan C. Evans, Mr. and Mrs. John L. Sullivan Jr., Clarence G. Donahue, Mr. and Mrs. John Sears, and a heartening number of “Coolies”, “Blackhawk Gang” returnees and members of the Academy Docent Council. Once again we are deeply grateful for the continued support of the Omali Lodge (São Tomé) and Bom Bom Island (Príncipe) for both logistics and lodging and especially for sponsoring part our education efforts for GG VII and GG VIII. Substantial support has already come in for our next expeditions from donors in memory of the late Michael Alan Schnoll, beloved husband of our island biodiversity education Project Manager, Velma.
Our expeditions can be supported by tax-deductable donations to “California Academy of Sciences Gulf of Guinea Fund”