We are going to have a full moon on Thursday, 6th July 2017. Our hardworking fishermen are going to take a deserved 7-day break from their daily routine. The fish get a reprieve and hopefully they replenish their stocks. Until the 13th July 2017, no form of kapenta fishing will be countenanced by both the Wildlife and Lake Navigation authorities. All fishing rigs are withdrawn from the lake and are anchored in their moorings. The question to be investigated is – have Full Moon fishing breaks helped our situation?

Historically, fishing stopped for a 4-day Full Moon break. The fishermen got to spend some quality time at home with their families. They worked 26-days a month, which was like the norm in those days. The Full Moon period was their “off days” at work. This tradition was not born out of conservation considerations, but out of practical economic considerations. We had more than enough fish stocks. Now they get an extra three rest days on conservation grounds – in the hope that this will help our kapenta stocks on Lake Kariba which have ostensibly been depleted by relentless overfishing. On face value it seems like a small effort, but let’s look at the results.
Why and how does the full moon affect fishing? As far as light fishing at night is concerned, the moon is a hindrance to progress because the period before, during and after the full moon, it has been empirically proven that fish are reluctant or even stop responding to artificial light (used for fishing). The reason for this was ably explained by Clarke, G.L. and E.J. Denton who in 1962, in an article titled “Light and Animal Life” carried by The Sea Vol. 1 – Physical Oceanography, edited by M.N. Hill, New York, Wiley Interscience pp456-68, observed that the distance at which a fishing light is perceptible naturally decreases with increasing general illumination. That was well before kapenta fishing was introduced into the then infant Lake Kariba.

In addition, the moon may also influence fish behaviour through lunar rhythms occurring in marine organisms notwithstanding the light conditions. During this period, fish catches are poor and to save costs and energy, fishermen rest. Fishing being a commercial business, why was the full moon period increased from 4 to 7 days? Has this had a marked improvement on fish stocks, particularly kapenta (Limnothrissa Miodon)? The Zimbabwe Parks and Wildlife Management Authority’s Lake Kariba Fisheries Research Institute notes that benefits in lake ecology recovery have been observed, though at a micro-scale. In correspondence to all Kapenta Industry Stakeholders dated 21 December 2016, the Institute’ s then Acting Officer-in- Charge, T.B. Matokwe, advised that the increased full moon period, which began on the 1st February 2015 as a result of a resolution passed at the 6th Technical Consultation Meeting, would continue in 2017 and beyond.

It should be noted that during the old 4-day full moon rest period, some fishing operations, curiously (and exclusively) emergent indigenous operators; ignoring tradition, conservation impact and the economies of scale, continued to fish during this period. The new regulations, however, impose a blanket ban on kapenta fishing. None of the fishing operators is afforded the liberty to exercise choice. Zambian fisheries authorities, with whom Lake Kariba is shared with, have gone further to impose a 10-day fishing ban during full moon in the area under their territory. According to the Lake Kariba Fisheries Research Institute, the full moon fishing stoppage “will continue indefinitely to increase the benefits which have been realized since it was implemented.”
Was it enough to just increase the rest days or that move should have been coupled with a reduction in the number of fishing rigs, which are admittedly too many on Lake Kariba, far exceeding the recommended number and holding capacity? Is overfishing the only problem threatening our fish stocks and Lake Kariba’s biodiversity? In the next instalment of this environmental series, this writer will shed more light on other factors negatively impacting on our fish stocks and how these are being addressed.

By Laiton Kandawire, a Patsaka Correspondent

About the Author: Laiton is an Incentive Travel Organizer, Kariba Destination Planner, Certified ZimHost, Travel Correspondent and a thriving Blogger. He can be contacted on: +263 772 817733 or by e-mail: ulakariba@gmail.com