Massive die-offs in the Kruger National Park: This park is expecting massive die-offs of animals due to one of the worst droughts in history. According to research findings published by Navashni Govender, senior chief manager of conservation in the game park, this is not mainly as a result of too little drinking water, but because of a shortage of grazing. In the short term, the drought has caused a loss of biomass, while in the long term, encroachment of wood species and a decrease in animal populations can be expected. Trees, elephants and predators survive better with a water shortage but grass eaters suffer. Currently, only half of the game park’s vegetation is available for these animals. The available biomass (grass) is 66% less than in 1992. Under normal circumstances, 4 000kg biomass per hectare is required, but only about 399kg/ha is available. While predators survive a drought better because more weakened prey is available, there is a sharp decrease of animal populations such as buffalo, hippo and buck. The current drought is much worse than the previous most serious drought (1991-92), as this drought was preceded by a much drier year (2014), and, since July 2015, the temperature had been much higher than in 1991-92. Although it did rain in March and April, it was too late, as the growing season was over. The heat and low rainfall also caused a lower water level in many of the rivers. Although anmials must travel further to reach drinking water, sufficient surface water is still available. (Hanti Otto, Beeld, 10 June 2016).
Australian mangrove die-off blamed on climate change: Some 7 000 hectares or 9% of the mangroves in the Gulf of Carpentaria, in Australia’s remote north, perished in just one month according to researchers from Australia’s James Cook University, the first time such an event has been recorded. Norm Duke, a mangrove ecologist from this university, said climate change was the likely cause: “We are experiencing an unusually long dry season. Droughts are normal, but not so severe”. The dieback occurred synchronously across 700km in one month. Some of the mangroves suffering “dieback” were defoliated, meaning they were not yet dead but had lost all their leaves, and could recover. Most will, however, not recover. Local rangers told scientists they were seeing creatures like shellfish, which need the shade of the trees, dying, and that turtles and dugongs that are dependent on the ecosystem could be starving in a few months. By all accounts, the climate is going to become more erratic in future, and these types of events are expected to become more common. (News 24, 11 July 2016).
Pecan nut terms: Pecan nut trees are hermaphrodites (androgynous), which means that the male flowers (Afr blomkatjies) and female flowers can be found apart and in different positions on the same tree. There is a time difference among different pecan nut cultivars for pollen production, so that cross-pollination can take place. This process is called diagagomy. Pecan nut trees are also heterozygous, which means that seedlings are not replicas of the mother tree. In most cases, seeds or nuts that are then planted do not perform as the mother tree did. The concept ‘biological control’ is increasingly practised by pecan nut producers, because of the resistance of certain plagues to chemical agents, pollution of the environment, poison residues on products, the increasing cost of insecticides, as well as the withdrawal of certain insecticides from the agro-chemical industry. Insect predators that feed on aphids include, amongst others, Ladybirds (Coleoptera coccinellidae), Lacewings (Neuroptera chrysopidae) and Hoverflies (Diptera syrphidae). The advantages of the larvae of these predators are, however, not so well known to producers. As the larvae increase in size, they moult, and each moulting stage is called instars. The larvae play an important role in the agro-ecosystem and provide free ‘biological control’. (SA Pecan, vol 73, Summer 2016).
Value for your money: In spite of potato prices having skyrocketed recently, a recent study have found that potatoes are the best buy as far as price and nutritional value is concerned. Although dark green vegetables contain the highest nutritional value density, researchers have found that potatoes offer more nutritional value per cent. It is one of the cheapest options for four key nutritional substances, namely, potassium, fibre, vitamin C and magnesium. One medium sized potato (150g), with the skin, contains more potassium than a banana, provides nearly half of your daily dosage of vitamin C and contains no fat, sodium or cholesterol. Potatoes are nature’s legal performance booster. It is readily available, quick and easy to prepare, delicious and natural – an excellent source of carbohydrates. Except for the fact that it boosts performance, it can also assist with the recovery process after a race or strenuous exercise. If you need fuel for a big race, get some potatoes! Visit www.potato.co.za for more information. (Sources: Health24.com, Livescience.com, BBC.CO.UK)
Did you know? The word ‘potato’ comes from the Spanish name for the tuber – patata. This is a joining together of two South American names – batata (sweet potato) and papa (potato). About 5 000 potato varieties are grown around the world. (Source: ‘International Year of the potato 2008’, United Nations Food and Agricultural Organisation).
...and possibly also humans!
Those bothersome flies zooming around during meal times in summer can help to make our world ecologically sustainable, says Jason Drew, founder and director of AgriProtein. This company in Phillipi, Cape Town (said to be the world’s largest fly farm) produces 7,5 tons of fly larvae daily, which consumes 110 tons of refuse, and is used to manufacture protein animal feed. This product, made from dehydrated fly larvae, is a substitute for fishmeal (which is very expensive) and soya meal (which is less effective). The fly larvae are also environmentally friendly as they are fed organic refuse such as left-over food or garden refuse that can be used as compost. The process relieves pressure on agricultural activities and fishing stock and leaves a smaller carbon footprint. Currently, the product is used as fish and chicken feed, but plans are under way to also use it as pet food. In future, it may be used in protein supplements for humans. All the products were tested scientifically in cooperation with the University of Stellenbosch (Sake Rapport, 22 May 2016).
By 2030, the cost for developing countries to cope with and adapt to changing climate conditions will amount to between $140 milliard and $300 milliard annually [a milliard is a thousand millions]
This is at least four times more than previous estimates, says the UN’s environmental programme (UNEP) in a report presented at the bi-annual Adaptation Futures conference in Rotterdam recently. Many cities in Africa and Asia do not have proper strategies to make changes, and are also concerned about financing such initiatives. According to Parks Tau, mayor of Johannesburg, it is estimated that it will cost this city about R116 million to prepare for climate change. The city can expect an increase in heat waves and exceptionally cold conditions in the near future. The eThekwini municipality in Durban, which is more exposed than Johannesburg, expect sea levels of more than a metre higher than currently by 2100. Rainfall will also increase, but it will rain at shorter intervals, which means that water levels will be much higher and that the water will flower much more rapidly. This will increase pressure on the city’s sewage system (Yolandi Groenewald, Rapport, 22 May 2016).
Higher temperatures and diminished rainfall are wreaking havoc in two of South Africa’s largest economic sectors – agriculture and energy. Yet, on the face of this growing crisis, the SA government continues to display unyielding allegiance to the nation’s water-guzzling coal sector, whose 50+ billion tons of coal reserves fuel 90% of the country’s electrical generating capacity and provide a third of its liquid fuels. When completed in 2020, the 4 800 megawatt Medupi coal-fired power station near Lephalale will consume 6.9 billion litres of water annually, which, according to forecasts based on the current drought, will not be available. Coal also generates hundreds of millions of metric tons of climate-changing carbon emissions annually that aggravate SA’s warming and drying. The other side of the coin is that 13 wind power plants and 31 solar generating stations are already operating in South Africa, and R95 billion has already been invested in renewable energy installations. The country appears well on its way to reaching the national target of 6 000 new megawatts of renewable energy capacity by 2020, and 18 000 new megawatts by 2030 (Keith Schneider, senior editor and chief correspondent for Circle of Blue, 27 May 2016).
Although cycads are not endemic to our area, the general state of cycad species in our country is of great concern to all who are in favour of a balance in nature.
Cycads are the most threatened group of plants on earth, with 62% classified as threatened in the 2010 IUCN global assessment. South Africa is a cycad diversity hotspot, with 37 species in die genus Encephalartos, yet 78% are threatened with extinction. The greatest threat to our cycads is illegal harvesting from the wild. Three species are already extinct in the wild, four are close to extinction, and another seven have fewer than 100 individuals remaining. The rate of loss has placed the existence of wild cycads on a knife’s edge.
A collaborative study between the SA National Biodiversity Institute and UCT is developing a solution to regulate the illicit trade in cycads by using stable isotopes to distinguish between wild and cultivated cycads. Having been used in numerous forensic studies, stable isotopes are now being applied to cycads.
As from May 2012, it is prohibited to harvest, trade, sell, buy, donate, import, export, convey or receive any wild indigenous cycad (even plants that have possession permits). If you suspect foul play, report this to the Department of Environmental Affair’s Environmental Crimes Hotline: 0800 205 005 (KZNCA email, 15 June 2015).
Healthy soil is the foundation of agricultural ecosystems. It builds healthy agricultural economies that, in turn, support national economies. “Soil is teeming with micro-organisms, fungi and bacteria. Just one teaspoon contains more than 100 000, and farmers, growers and gardeners are becoming aware of the huge role they play” (Bunny Guiness).
South Africa is a water-scarce country, and there is limited soil for agricultural production. Of the 100 million ha of farm land in South Africa only 12,75 million ha is arable agricultural land, some of which is prime land, i.e. more arable than the bulk. In fact, a full 47% of agricultural land is unsuited to cultivation of any kind, suitable only for grazing, game, recreation, etc. Using techniques such as no-till planting, deep mulching with natural compost, companion planting and conservative drip irrigation, helps with carbon sequestration and lowers the loss of carbon and moisture from the soil. It prevents large-scale erosion through wind and water and improves soil health, leading to improved yield and sustainable production over time. Maximum cover on top of the soil – plants, either living or dead, serve as armour for the soil, just as our epidermis forms an armour against the sun and rain. It keeps the soil cooler in summer and warmer in winter, provides food for the soil organisms that help sequestrate carbon, and builds soil structure. For every one percent of added carbon to the soil, the water-holding capacity of that soil doubles (Dr Johan Strauss & Richard Findlay, Farmers Weekly, 14 October 2014).
According to soil health expert, dr Jill Clapperton, healthy soil will comprise a large number of functioning soil services, including: Limited soil erosion due to high soil organic matter content; increased nutrient cycling; good nutrient availability and nutrient recycling; good water-holding capacity and water filtering; and good biodegrading of potentially toxic compounds from the likes of chemical fertilisers and agricultural chemicals in the soil: “Today’s intensive use of nitrogen fertilisers, besides supplying the most important plant nutrient for achieving high yields, is generally believed to build soil organic matter by increasing the input of residue carbon as well as supplying nitrogen, itself a key constituent” (‘The Browning of the Green Revolution’ by RL Mulvaney, SA Khan & TR Ellsworth).
Humus is a complex and rather resistant mixture of brown or dark brown amorphous and colloidal organic substance which results from microbial decomposition and synthesis, and it has chemical and physical properties of great significance to soils and plants (Gauteng Smallholder, September 2015).
Tax on sugar-sweetened beverages announced: The scientific reasoning behind the tax on sugar-sweetened beverages (SSBs) aimed at controlling obesity among South African adults, has been described as “nonsense” and “an insult to the integrity and intelligence of real science”. A paper released by the University of the Witwatersrand recently stated that “a 20% tax on SSBs is predicted to reduce energy intake by about 36kj/day. Obesity is projected to reduce by 3,8% in men and 2,4% in women”. According to the South African Sugar Association’s executive director, Trix Trikam, “there are many causes of obesity and perhaps just as many solutions. The sugar industry believes in maintaining a balance and following the South African dietary-based guidelines. Unfortunately, there is no silver bullet for obesity (including a tax on sugar and sugar-containing products), as both scientific and historic evidence shows” (Lloyd Phillips, Farmer’s Weekly, 26 September 2014).
World Wetlands Day and Leap Day for Frogs: The 2nd of February was World Wetlands Day. The Endangered Wildlife Trust’s (EWT) fourth annual Leap Day for Frogs, a national day of awareness and celebration of frogs, will occur on the 27th of February. Amphibians are among the most endangered species on earth, with 43% of the species populations declining globally. Around 120 species of frogs call South Africa home, of which many are endangered. South Africa’s smallest frog is also one of its most threatened. The appropriately named Micro Frog, which will only grow to a maximum length of 18 mm, is critically endangered, and our largest species, the Giant Bullfrog, which reaches 25 cm and weighs in at 1.4 kg, has already lost up to 80% of its habitat, particularly in urban areas of Gauteng. Visit www.leapdayforfrogs.org.za for more froggy facts. You don’t have to be a scientist to save frogs! Leap Day for Frogs is an opportunity to increase awareness around the importance of frogs, and to remove the negative stigma and superstitions that have unfortunately surrounded these fascinating creatures for many decades. Dr Jeanne Tarrant, Manager of the EWT’s Threatened Amphibian Programme highlights the importance of this initiative. "Understanding why many South Africans fear or dislike frogs is essential to changing the attitudes towards these animals, and ultimately protecting them. There is a genuine growing interest in ‘frogging’ and Leap Day for Frogs also encourages learning more about, and celebrating, the amazing diversity of frogs in South Africa, especially amongst our youth". Frogs are crucial in our ecosystems through their role as both predator and prey. They are also important bio-indicators of the health of the environment, and the fact that almost half of all species are declining should be a clear warning that our global ecosystem is under strain (email received on 3 February 2016).
Urban carnivores: South Africa’s urbanites are getting used to baboons and monkeys, attracted by food, in their backyards. Predators, too, are getting closer. In September 2013, a young brown hyena had to be captured in Blairgowrie, Johannesburg. A small pack of them is reported to live in the green belt spanning the west of the city. A wide variety of carnivores appears to be surviving – despite a lack of conservation efforts – on the fringe (within 20km) of one of the largest human populations in SA, according to Dr Brian Kuhn of the Paleosciences Centre at the University of the Witwatersrand. Brown hyenas, black-backed jackals, servals, caracals, mongooses, honey badgers and a leopard have been spotted in and around the Cradle of Humankind (Roelof Bezuidenhout, Farmer’s Weekly, 3 October 2014).
Indigenous veld goat types: Indigenous goats arrived in South Africa with migrating tribes and are found in the specific areas where the different ethnic groups settled. The general appearance of these goats tends to support theories that they originated in different ecosystems. The Boer Goat is famous throughout the world as a hardy meat goat, with a high resistance to disease and an ability to adapt well to hot, dry, semi desert conditions. However, this breed is the result of selective breeding which drew on a variety of goats found locally, particularly in the Eastern Cape. There are four distinct eco types of indigenous goat (excluding the Boer Goat):
Nguni type goats (Mbuzi) – multi-coloured with semi pendulous ears
Eastern Cape Xhosa – multi-coloured with lob ears
Northern Cape, Lob Eared, Speckled (Skilder) Goats
Q Kunene Type (Kaokoland) – multi-coloured with lob ears
(For more information: 083 383 2737 or 051 445 2010 or go to www.indigenousveldgoats.co.za).
When the veld turns toxic: One of the greatest risks to livestock in South Africa is plant toxicity. Toxic plants are usually the first green plants to sprout after a dry season or a veld fire. A number of these are at their most toxic in the young stage when they are most attractive to livestock. Similarly, some are highly resistant to drought and may be the only green plants available during drought.
What to look out for: Toxic plants are often found as weeds in harvested lands and along the roadside (areas frequently used for grazing in times of scarcity). Certain poisonings occur after a sudden change in the weather, usually after an unseasonable frost or when wet, cool conditions are suddenly followed by a warm, dry spell. Wind or hail can knock poisonous acorns or pods to the ground, making them available to animals. Fodder such as hay, silage, stover or concentrates may contain toxic plants, fungi or chemicals.
Plants to watch out for: About 600 indigenous toxic plant species occur in South Africa. Different parts of these (e.g. leaves or seeds) may be poisonous. For cattle, the most common poisonous plants include those producing cardiac glycosides (tulp and slangkop, e.g. gifblaar (Dichapetalum cymosum); Fadogia homblei (causing gousiekte); and Lantana. Dangerous plants for sheep and goats include plants causing geeldikkop, Vermeersiekte, gousiekte and diplodiosis; sceneciosis; and plants producing cardiac glycosides.
(Source: ‘Poisonous plants’, Animal Health for Developing Farmers Programme, ARC-Onderstepoort Veterinary Institute).