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NEWS NEWS Study suggests climate change may The shocking truth about kill off the aardvark in some areas electric fences Bob Yirka Alan Lee and Matt Macray Current Address: Bloomfield, Indiana, United States Current Address: University of Cape Town, South Africa E-mail Address: not available E-mail Addresses: [email protected] and [email protected] Reprinted From: https://phys.org/news/2017-07-climate-aardvark-areas.html Reprinted From: https://view.joomag.com/agri-kultuur-august-agustus-2017/0074993001502436356?tok en=xBd7xtAGSSqOjuMAXE079CyonuCXH6JEuASZgURJclFw6PujtbJKflD8HvdW%2BvQSYVN3BO09i8T team of researchers with the Uni- ment. This was backed up by measure- nantly nocturnal and distributed widely ht2qjI6kvC7DV%2BMMp9XvyAkL6roI1TI0BWRY8LuiudbKYcXJBjG36lXqGsFMkVOhK%2FjUU5MZwoSGl versity of the Witwatersrand in ments of extremely low body weight. throughout Africa except for arid de- DxOm3y7f A South Africa has found evidence The researchers suggest the reason serts. Their survival may be threatened that suggests the aardvark may face the aardvarks had trouble finding food by climate change via direct and indi- a large decrease in population as the was because ants and termites need a rect effects of increasing heat and arid- n South Africa, we have a fence loving viduals, 35 alive), followed by Angulate appear to wedge themselves in mesh planet heats up due to global warming. certain amount of water in the soil to ity. To measure their current physiologi- culture: no-one has grown up without tortoises (54 individuals, 5 alive) and fences and are unable to escape. This In their paper published in the journal survive. The aardvarks that died had cal plasticity, we implanted biologgers Ifencing of some kind. Fence types de- tent tortoises (5, all dead). Unsurpris- study highlights the current threat of Biology Letters, the group describes starved to death, the researchers con- into six adult aardvarks resident in the pend on land-use types, but recently ingly, Leopard tortoise mortalities were non-electric fencing on tortoises as no how they fastened monitors to a group cluded, as had several other aardvarks semi-arid Kalahari. Following a particu- there has been a rapid growth in the significantly higher along electric fences similar findings have been reported. of aardvarks who by happenstance were they observed in areas around the test larly dry and hot summer, five of the use of electric fencing to control prob- than non-electric fences. Despite form- These additional tortoise mortalities forced to endure a severe drought— site. This, the team suggests, indicates study aardvarks and 11 other aardvarks lem animals as well as manage large ing only approximately 4% of all road- should be considered alongside other and how the animals fared. that aardvark populations are likely go- at the study site died. Body tempera- game species, particularly in the wildlife side fencing, electric fences account for emerging threats when questioning ing to plummet as their habitats grow ture records revealed homeothermy ranching sector. However, recent stud- 56% of leopard tortoise mortalities. the longevity of these tortoise popula- Aardvarks are interesting mammals, to hotter and drier. (35.4–37.2°C) initially, but heterothermy ies have found that leopard tortoises tions, not only in the Karoo, but glob- (Stigmochelys pardalis) are prone to Matt also recorded Angulate tortoises ally. For instance, Pied Crow have been say the least; they have floppy ears, a increased progressively through the tubular snout and a body reminiscent More information dying from electrocution along electric (Chersina angulata), a smaller tortoise recorded to feed on small and juvenile of an armadillo. They survive by hiding summer, with declining troughs in the fences, more so than any other wildlife. of up to 30 cm length and 2 kg. Mor- tortoises. from sub-Saharan African heat inside Benjamin Rey et al. Drought-induced nychthemeral rhythm of body temper- talities did not differ between electric burrows they dig and eating ants and starvation of aardvarks in the Kalahari: ature reaching as low as 25°C before The Leopard tortoise is the largest and non-electric fences, likely due to Implementation and practicality of termites at night. As the researchers an indirect effect of climate change, death, likely due to starvation. Activity (with exceptional individuals reaching the lower shell height. A novel finding mitigation strategies note, aardvarks are considered to be a Biology Letters (2017). DOI: 10.1098/ patterns shifted from the normal noc- lengths of 750 mm and masses of 40 was that mortalities of this species were keystone species because others ani- rsbl.2017.0301 turnal to a diurnal mode. Our results do kg), most abundant and widespread higher along diamond mesh fences Raising the electric strands has previ- mals use the burrows they build as nests, not bode well for the future of aardvarks tortoise across South Africa. This makes than strand fences. Angulate tortoises ously been suggested, but was rarely sleeping quarters or simply as a place to Abstract facing climate change. Extirpation of them very prone to contact with low- escape from predators and the intense aardvarks, which play a key role as eco- strand electric wires. Upon contact, desert heat. But their very existence Aardvarks (Orycteropus afer) are elu- system engineers, may disrupt stability the tortoise defence mechanism is en- might be in jeopardy, the researchers sive burrowing mammals, predomi- of African ecosystems. gaged: this involves retracting head and with this new effort have found, as the limbs into the shell, often remaining in planet heats up and conditions in parts contact with the live wire. The animal is of Africa become more inhospitable. then consistently shocked, with death occurring after a prolonged period of As part of an ongoing study of the crea- terrible pain due to dehydration, over- tures, the researchers affixed sensors to heating or internal organ failure. the bodies of several specimens and then released them back into the wild. With South Africa being home to more The sensors tracked both body temper- tortoise species than anywhere else in ature and activity. As it turned out, the the world, this is a major concern. A re- period of study happened to occur dur- cent study by student Matthew Macray, ing a particularly hot and dry spell in the based at the University of Cape Town, area, offering an opportunity to see how quantified tortoise mortalities associ- the aardvarks might fare as sub-Saharan ated with electrified and non-electrified Africa grows hotter and drier. fences, comparing these to areas of veld with no fences, in the Karoo re- As it turned out, the aardvarks did not gion stretching from Prince Albert to fare well at all—five out of six of the Steytlerville. Here, low-line electric fenc- monitored creatures died from appar- ing is commonly used to protect An- ent unnatural causes. Study of data from gora Goats from jackal, amongst other the sensors showed that the animals purposes. had swapped their usual routines, ven- turing out during the day to eat, rather Matt found 403 tortoises on over 160 than at night. They also showed that the km of on-foot survey routes, only 40 body temperature of the animals had of which were alive. Leopard tortoises declined—an indication of malnourish- Figure 1: Aardvark mother and young. Credit: Wikipedia/CC BY-SA 2.0 were most commonly found (344 indi- Figure 1: Angulate tortoise trapped in mesh fence 21 Grassroots Vol 17 No 4 November 2017 Grassroots Vol 17 No 4 November 2017 22 NEWS NEWS observed, and is impractical for control- toise mortalities without compromis- and remove tortoises trapped on the ling the movement of unwanted wildlife. ing fence function. High temperatures fences. Despite having electric fences, The implementation of rock aprons also are associated with later periods of the he was still suffering stock loss due to appeared to be ineffective at reducing day, periods when traditional problem predation by jackal, making it question- What camera traps tell us about mortality rates, in some cases lowering animals are rarely observed. Switching able whether the fences were proving the contact height between low electric fences off during these periods could effective: there is certainly a need for strands and the ground level. However, allow time for tortoises to escape the further research regarding this. Placing elephants eating crops tortoises displayed active behaviour fences. In the Baviaanskloof area, one fences away from tall vegetation and when the temperature was above 20°C, farmer concerned about the impact of water may also help reduce fatalities. thus thermostatic switches for electric his fences on tortoises, employed a staff Overall, a proactive attitude to mitigat- fences could potentially reduce tor- member to patrol the fence every day ing tortoise mortalities is required. Josephine B Smit Current Address: University of Stirling, United Kingdom E-mail Address: [email protected] Reprinted From: https://theconversation.com/what-camera-traps-tell-us-about-elephants-eating-crops- 81149?utm_medium=email&utm_campaign=Latest%20from%20The%20Conversation%20for%20 August%202%202017%20-%2079926399&utm_content=Latest%20from%20The%20Conversation%20 for%20August%202%202017%20-%2079926399+CID_1f9f41d66021104eb65ce58438a05cee&utm_ source=campaign_monitor_africa&utm_term=What%20camera%20traps%20tell%20us%20about%20 elephants%20eating%20crops n important conservation goal is High-risk, high-reward mands. Crops are an attractive source to try and ensure that people and of food for males seeking to maximise Awildlife can coexist. This is espe- All the elephants photographed by our their body size and reproductive suc- cially important when it comes to el- camera traps were males. This is con- cess. ephants, whose large home ranges and sistent with previous studies suggest- long distance movements take them ing that eating crops is a high risk, high How do males learn about crops as a outside of protected areas.