As I write, Batoka Gorge dam is set to go ahead and will be a reality within the next decade. It is the lesser of evils, but an evil nonetheless. Mupata Gorge will also likely happen once the Mana Pools area loses significance should proposed mining operations there go ahead as suggested in a recent report in Zimbabwe’s Sunday Mail. Apparently a sedimentologist and geological consultant Dr Dennis Shoko said about surveys done by Mobil in the Zambezi Valley “They worked on the structure of our basin in areas such as the Mana Pools, the Cabora Basin and Zambezi Basin. Remember we also share this basin with Mozambique, which has also discovered oil.” The government apparently plans to start drilling.

Indeed, natural gas to feed thermal power stations would alleviate pressure on dams needed for hydroelectricity and solve our electricity woes... but at what cost, and is it really too high considering the alternatives? Do we destroy a massive and unique wilderness like Mana with mining operations (oil can be really messy) or the Mupata Gorge dam, or do we flood a narrow gorge at a section of the Zambezi where its impacts will be less dire? This is not to say that the Batoka Dam will not have an impact. 

The proposed dam site is located near the Kabompo Falls, a constriction in the river canyon and when complete will rise 181 meters (one of Africa’s tallest) creating a 50 kilometer long reservoir that would flood the gorge upstream to Rapid 5, just below Victoria Falls. The  1 680 million cubic meter reservoir will cover an area of approximately 26 square kilometers. The project would drown the Zambezi’s iconic big-water rapids and devastate river-based tourism activities like kayaking and white water rafting which is reputed to employ about 700 people (on both the Zimbabwean and Zambian sides) and generates some $4 million annually. The project has been estimated to cost in the region of $6 billion, but according to a recent analysis of large-scale dam projects across the globe, the actual costs of dams are “on average 96% higher than estimated costs.” The project will take 10-13 years to complete and once in full operation will generate 1,600-megawatts split between Zambia and Zimbabwe. Zimbabwe is reported to have a power deficit of 800MW currently, so the project is unlikely to solve any problems ten years hence.

A significant pro for the dam is that it will not inundate a large land mass and is in a low settlement density area, minimizing the number of people that need to be resettled. However, the gorge is a habitat for a number of rare bird species, and the project is expected to have major impacts on local endangered species. Birdlife International lists the Batoka Gorge as an ‘Important Bird Area’ on the basis of its conservation importance. Four species of note breed in the gorge, including the Taita falcon (a small, agile endangered raptor). Another 34 raptor species are also found in the gorge, including rare birds of prey such as Verraux’s eagle (previously known as the black eagle).  This loss is significant but is it acceptable when compared to the loss of Mana Pools?

Many argue that the flooding of that section of the river will destroy significant tourism appeal, without offering much future opportunity in return, and that it is unclear how surrounding communities would benefit, if at all, as few are linked into the national power grid. I would argue that a 50km dam, of a unique formation as the gorge will provide, would more than compensate with other water-borne tourism activities in the future. Some argue it will not offer any significant fishing opportunities due to its depth though it is expected that certain species will indeed find a niche in the dam, and while they may not be prime as far as us hardened Zambezi anglers go, species like Niloticus, vundu and the like may well provide a prime attraction for visiting anglers. Access to the water in the gorge for both tourism and utilisation would be significantly easier, and offer many opportunities along the river. At present, it is 1000 feet below ground level and unless you have a bent for rafting, of little use to the mainstream populace. I have no desire to raft - aside from being dangerous (relative to my usual activities) one risks heart failure getting in and out of the gorge, but man would I - and likely many more thousands of others - love to get on that section with a boat and fishing rod. 

Indeed, there are many other factors to consider, not least of all the effects on the river downstream. Other impoundments have already impacted negatively, adding to degradation of coastal mangroves; reduction in freshwater and prawn fisheries, floodplain agriculture, floodplain water supply and wildlife carrying capacity; and biophysical impacts such as the down-cutting channels in the delta and reduction of the water table level. An additional dam would worsen these impacts. Added to which an extensive 2012 report on the hydrological risks to Zambezi River dams reported climate change is predicted to cause a 25 to 40 percent reduction in the river’s flow, which could significantly compromise the hydroelectric productivity of the Batoka Gorge project. According to a report by International River “Harrison & Whittington (2002) carried out some climate modeling on the proposed Zambezi dams and found that the Batoka Gorge Dam is likely to lose 6-22% production due to declining rainfall as a result of a warming climate in the basin. In his 2012 report on the hydrological risks of planned Zambezi dams (Batoka included), Beilfuss reported that these dams are unlikely to deliver the expected services over their lifetime.”

Impact Assessment Studies were carried out many years ago, and are being up-dated as I write.  The sensitive raptor breeding sites have already suffered due to noise - mostly helicopters flying close to, or in the gorge - and will no doubt come under further pressure from the dam and associated activities. Key aquatic insects which breed in the fast rapids and form the basis of a food chain vital to the Taita falcon will be lost. Could these be replaced by other aquatic insects? Would the raptors necessarily move? The questions can go on forever. One thing is agreed, and that is if the dam and its environs was to be managed to limit noise and disturbance, this may go some way to protecting sensitive Flora and Fauna. 

It is hard to say with any certainty what the Batoka Gorge project will bring. Few are writing or predicting anything positive and the public swell against it is mounting. But we need to be reasonable in our objections. Simply objecting to everything that is proposed will result in authorities turning a deaf ear to unrelenting objections usually based on emotive issues. In my opinion, Batoka is definitely the lessor of all the hydro-electric evils at this time, and in the long term - as Kariba has done - may well provide significant spin-off benefits not associated to the hydro-electricity function, not least of all increased tourism. I believe it will boost tourism in and around the Falls - a sentiment echoed by some lodge operators in the area and along the gorge itself. 

One opposition group (with a face Book page) known as “Stop The Batoka Dam On The Zambezi River” stated on 5 December 2014 after a meeting with Environmental Resources Management (ERM) who are doing the Environmental and Social Impact Assessment (ESIA) for the Batoka Gorge Dam (based in Cape Town) “From our meeting I feel these people are approaching this in a professional and very thorough way. Having said that, we were able to open their eyes to a number of issues that they were not aware of and which they duly noted to include in their research.” They also pointed out funding for construction has not been approved with only the ESIA having been funded by the World bank so far. It seems, a final decision will be taken dependant on the advice of the ESIA. Fingers crossed.

By Anthony Williams

Flying ants, are more correctly defined as winged termites, who after the first rains, take to the air in their millions to propagate new colonies. Most species of flying ants are blind, with the exception of the full sighted ant which is particularly common at Kariba. Without delving into the Latin names and technical terminology of the various species, Trevor Wilton (a recognised authority on the ants and their behaviour), classifies them as the bigger "red Termite" and the "orange Termite" a smaller creature more frequently found in the southern areas of Zimbabwe. While the "red" ant will typically be found coming out of the familiar ant mounds, its "Orange" brother seems to emerge from holes anywhere in the ground, and is therefore more difficult to target and capture unless a bright light is used to attract them after they have taken to the air.

Weather patterns across southern Africa seem to be out of kilter... again, and in Zimbabwe high blue winter skies dominated October (supposedly the suicide month) and November, forcing us poor fishermen to don a jacket some mornings. The rains spluttered into life, and with them the ants, and while we struggle under a deluge of rain now, causing extensive flooding across the region, the ants persist. This water flowing into the rivers and dams, heralds a spark of fishing activity hard to beat. 

Flying ants normally emerge after the first decent rains have occurred, 5-10mm will do it, and will usually take flight at last light, between 6pm and 7pm. Prior to the actual emergence of the ant, increased activity around mounds will be noticed. From about mid November, fresh (wet) mud will be noticed on some mounds, as the ants carry out underground construction. Worker ants appear up a series of slits (as opposed to the more common honeycomb round holes of the mound) and these exits are guarded by soldier and bull ants. As dusk approaches, this activity increases until winged ants begin appearing, at which point the mound should be left alone. Only once the flight has become continuous can one start collecting the ants. Caution should be exercised, as the soldier and bull ants are there for a reason, and will attack careless fingers, sinking their nippers into one's flesh, inflicting quite a painful bite.

Some Tips on Using Ants

Just about every specie of fish will eat flying ants if presented correctly. Elsewhere in this issue, a technique for rendalli has been covered, which will work for most other bream species. Niloticus are very similar in their behaviour, and if one can get on to a farm dam stocked with these fish, some nice specimens can be taken on flying ants.

The Kariba bream, or mozzie as they are affectionately known, are also partial to ants, although they are more difficult to locate and entice. A thin wire trace is advisable (about 10cm long), as tigerfish will often take the bait. Two or three ants should be placed on the hook, and a bubble float used to suspend the bait just below the surface. It seems mozzies will usually only rise when attracted by the feeding of other fish, especially the tiger.

Tigerfish are particularly partial to flying ants, and once they have the taste, will whip the water to a froth in a feeding frenzy. During the flying ant season, many anglers carry a good supply of ants when at Kariba. While spinning for tiger through the tree lines, a hand-full of ants should be thrown onto the water from time to time, especially if any surface activity is observed. 

When the tiger boil to the surface, they will seldom accept submerged ants, and the angler needs to keep the ants on or close to the surface. A thin piano wire trace fed through a large porcupine quill with a hook tied approximately 10 to 15 centimetres from the float will hold the ants on the surface. Four or five large ants (preferably with wings) fed onto the hook will make an attractive meal.

Another technique is to thread a couple of ants onto a tiger spinner and retrieve the bait slowly through the feeding shoal. The size of the bait does not limit the size of fish. Tiger are so partial to flying ants that even those in excess of five kilograms will attack the small offerings.

To target tiger (or indeed mozzies) is a little hit and miss. One of the methods used for locating fish is used in the Sanyati gorge at Kariba, and entails trolling from bank to bank tossing out handfuls of ants to float on the surface. Once a line of steadily drifting ants has been laid, motor fifty metres or so away, kill the outboard, and drift along silently behind the bait. Should the ants drift over a shoal of tiger, or the tiger home in on the free offering, the attack cannot be mistaken. Noisy rises as the fish smash the ants from the surface indicate their presence. Often smaller fish will be attracted first, so wait a while until the bigger fish are evident. If necessary, keep throwing the occasional handful of ants onto the water to keep the fish interested until the bigger tiger arrive.