Extracted content of prev. attachment- Akure Terrapin Turtle Species

[Folarin Kolawole]

Folarin Kolawole

February 2, 2011 at 2:38 am #22931

Attachments :Pool A at the peak of the rainy season. Algae-like plants form along the water surface..jpgFig 9. Showing cross-section A-A of Pool-A..jpgFig 8. Showing Pool-A formed in granite and a strip of xenolith cutting across it..jpgFig 6. Pool-A. Notice the arrow pointing to a narrow crevice (cut-off tunnel) near the base of the drying pool..jpgAkure Terrapin Turtle Species By Folarin Kolawole Their Discovery In may 2003, a species of terrapin turtles was discovered in Akure, Ondo State capital, Nigeria; subsisting in a harsh and unusual habitat- rock pools (gnammas) on massive granite inselbergs (hills with steep sides and rounded tops). The Akure landscape is a typical inselberg landscape especially around its northern outskirts. This area falls essentially on the southern fringes of Ikere Batholith (a large cluster of granite hills). Shortly after the first discovery, another gnamma within the same area, but on another inselberg was discovered to contain a community of these same species. Since then, there have been various efforts to bring to the knowledge of the state government, the presence and the endangered state of the species. These efforts have also ended in futility due to government___s insensitivity and lack-luster attitude to the subject of tourism and conservation of natural resources in the country. During the past seven (7) years, the species and their habitat have been closely monitored and their behaviours carefully observed. This was the major inspiration for Naijatreks Foundation. We are determined to ensure the successful protection and conservation of these wonderful animals and their habitat. Diet: The terrapins have been observed to live on a diet of earthworms, small insects (e.g. soldier ants, termites, cockroaches, possibly water skeeters) and edible leaves. Head: This terrapin species possesses a “snouted-head” i.e. a pointed head with the front tip characterized by the presence of a snout at which its nostrol is also present. Since these species are omnivorous, when attacking a worm for example, they are able to move their heads quickly to snap. Their eyes are located close to the top of their head. These species of turtles can hide from predators in shallow water where they lie entirely submerged except for their eyes and nostrils. Neck-folding: The Akure Terrapin turtles belong to the Pleurodira, which contract their necks to the side. Shell: The shape of the shell gives helpful clues to how this terrapin species lives. The species has a flat shell which give buoyancy when it is inside water. This also allows it to gain access into narrow crevices at the base of its gnamma habitat. Limbs: The Akure Terrapin turtle have developed adaptations for an aquatic cum terrestrial habitat. They have what can be described as webbed limbs in the sense that the limbs have sharp claws set at the end of a flattened and webbed palm; the webbed palm help to swim conveniently in water and the sharp claws help to move on the rocks. The turtles fly through the water, using the up-and-down motion of the front webbed limbs to generate thrust and the rear webbed limbs may serve as rudders for steering. From time to time during the day, they swim to the surface and crawl out to the slopes of their rock pool home to tan in the sun. Hibernation: The nature of hibernation (brumation) of the Akure Terrapins is still a thing of mystery. The dry season gets very severe around the December/January periods of every year, during which most of the rock holes on the granite hills in the area dry up (including one of the two known to be occupied by the terrapins) due to the excessive heat it absorbs during this hot season. During this period, the terrapin pool dries up leaving a hard and thick sediment deposit at the base. The surface of this deposit is usually very hard and almost impermeable except by prolonged watering. Based on this, it is believed that the terrapins hibernate beneath this thick and protective deposit throughout the duration of the harsh season. These are illustrated in the figures 11-12 below. Egg-Laying: From observations, the entire area is too open and unsafe for the terrapins to crawl out to lay eggs. Therefore they must have been exercising a stronger control on the safety of their eggs by using a more confined zone for their egg-laying. There is a crevice at the base of the pool whose entrance gets a little exposed when the pool dries up. I believe that this crevice serves as the place where they lay their eggs, since turtles are known to lay their eggs on land and not inside water. This crevice may also serve as a hibernation zone for the turtles. These are illustrated in the figure 10 below. Akure terrapins and people: They are aware of predators and people and generally shy away from them. They frantically slide off the rock and jump into their pool when approached. The habitats (Terrapin Pool-A and Terrapin Pool-B) The first pool discovered was the one named ”Pool-A” and the second is the ”Pool-B”. Pool-B is bigger and has larger samples of the turtles than Pool-A. Apart from that, Pool-B is located on an inselberg that is less accessible (Agbawa Hill) compared to Mesan Hill, on which Pool-A is located. This high inaccessibility is as a result of the steep sides of the Agbawa Hill. The hill has fewer bushes on it, mostly bare rock all over. Mesan Hill is broader at the top and has many bushes all over, even forest in some parts. Local subsistent farmers are using some parts for farming. Pool-A dries up during the dry season but Pool-B never dries up completely all through the harsh season. Why are theAkure terrapin Turtles endangered? According to the IUCN Red List of Threatened Species, Akure Terrapin species can be classified as endangered considering the high risk of extinction they are susceptible to in their present location. 1. The presence of human activity near and around their habitat has increased over the years; especially at one of the rock pools where some religious people often come to pray because they believe they are closer to God at the hilltops (proximity to the skies)- the wax from their praying candles can be seen littering the rock surface some 8-10m away from the rock pool. They have also erected a big wooden cross at the site. Rain falls on these rocks and washes these substances down into the turtle pool because it is located down slope. Farmers and adventurous youths climbing the hills had stumbled on the pool and noticed the presence of turtles there and had retrieved some samples which they never took good care of and had died in their possession (someone made a self confession). 2. Also, people stumble upon the habitat and in an attempt to retrieve the turtles from their pool; they throw all manner of objects into the water. These objects, when left in the water may contaminate the water and destroy the habitat. 3. Global warming is also another major threat to the habitat especially one of the pools, although the turtles seem to have devised a special hibernation adaptation for the tough dry seasons. Nevertheless, their existence becomes increasingly endangered with increase in the severity of global warming. Model for Akure Terrapin Habitat (Pool-A Model) The model was developed based on observations at one of the rock pools (Pool A). I believe the “cut-off” tunnel was formed by weathering of the xenolith cutting across the granite in which the gnamma itself is formed. A xenolith is a partially digested pre-existing rock material carried up in the rising magma at the time of formation of the intrusive rock (granite). The xenolith found here is obviously made up of a softer rock which is more susceptible to weathering than the enclosing granite. These are illustrated in Figures 8-9 below. Note: If upon investigation of the internal structure of Pool-B this model doesn___t apply (i.e. if no presence of a cut-off channel), we may have to believe that the Akure Terrapin species lay and hatch their eggs in water- this is highly speculative though. (Attached pictures can be found on the ”Attachment” page of the group). Yours, F. Kolawole Naijatreks Foundation, http://www.naijatreks.com “Only in the minds of a select group of thinkers does a universe begin to divulge its secrets”

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