Foto: Jennifer Adler
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Tan­zania: In­de­pend­ent un­der­wa­ter sea sponge farm­ers of Zan­zibar

What is at is­sue:

The aim of the pro­ject is to im­prove the liv­ing con­di­tions of the in­hab­it­ants of Zan­zib­ar's coasts, whose in­come has been de­clin­ing for years due to cli­mate change and the rising cost of liv­ing caused by tour­ism there.

Most of the be­ne­fi­ciar­ies of this pro­ject are single moth­ers. The wo­men are trained as sponge farm­ers. Each farmer will have her own farm, from which she will be able to live after one year by selling the sponges.

Film re­port - For most of her life, Zedi Ab­dul­lah Ab­dul­lah looked at the sea in front of her vil­lage with fear. Then she gathered her cour­age, learned to swim and star­ted sponge farm­ing. Today she is fin­an­cially in­de­pend­ent and a re­spec­ted per­son in the vil­lage.

On marinecultures.org website

What's hap­pen­ing now:

The monthly in­come of the wo­men farm­ers var­ies. For those who are sys­tem­atic, the sponges provide good in­come. In or­der to in­crease com­mit­ment and in­come, the newly foun­ded sponge farm­ers' co­oper­at­ive has de­cided to no longer give new farms to the farm­ers free of charge, but to grant them tem­por­ary leases.

Since the start of the pro­ject, there has been a mor­tal­ity rate of between 10 and 30 per­cent among the sponges caused by pests and dis­eases. In Septem­ber 2021, however, al­most all of the sponges were lost, with about 15,000 sponges in 15 farms. The loss of in­come for the wo­men farm­ers is enorm­ous; they only have sponges to sell for 2-3 months un­til their stock is empty.

Changes in en­vir­on­mental con­di­tions, wa­ter pol­lu­tion and/​or a fungal or bac­terial in­fec­tion have been cited as pos­sible reas­ons for the mass die-off. Wa­ter and sponge samples have already been col­lec­ted and sent to Olden­burg Uni­versity in Ger­many for ana­lysis.

In the rear­ing farm in deeper wa­ter (4-9m depth), the loss was sig­ni­fic­antly lower than in the pro­duct­ive farms (0.5-4m depth) near the shore. There­fore, all re­main­ing an­im­als were evac­u­ated to deeper wa­ter. In ad­di­tion, the farm­ers thor­oughly cleaned all the farm ma­ter­ial and re­moved the dead sponges from the seabed.

An­other cause could be the mono­cul­ture of the sponges. Sea­weed (spe­cies Spinosum) has now been cul­tiv­ated in the empty farms for the first time, so that the farm­ers will at least have some in­come for the next 8 months. As soon as pos­sible, new sponge frag­ments are to be brought back to the pro­duct­ive sponge farms and hung among the seagrass.

The sponge farm­ers' co­oper­at­ive is es­tab­lished and the of­fi­cial re­gis­tra­tion pro­ced­ure has star­ted. The plan for 2022: Ex­pan­sion of the num­ber of pro­duct­ive farms, cul­tiv­a­tion tests of vari­ous sea­weeds and al­gae (e.g. Ulva/​Sea Lettuce) for the pur­pose of mul­ti­cul­ture, train­ing of the sponge farm­ers in the man­age­ment of the co­oper­at­ive in­clud­ing ac­count­ing, han­dover of all sales activ­it­ies in­clud­ing qual­ity man­age­ment. Sim­pli­fic­a­tion of the sponge nurs­ery man­age­ment.

What we have achieved:

In the first phase 2010 - 2015, the loc­ally oc­cur­ring sponges were re­searched to­gether with the pop­u­la­tion of Jam­bi­ani on the east coast of Zan­zibar and meth­ods of cul­tiv­a­tion and mar­ket­ing were de­veloped.

In the 2016 - 2019 phase, the sponge farms were de­veloped and a local mar­ket for the nat­ural sponges was opened up. The sponge farms en­able the wo­men farm­ers to earn an in­de­pend­ent in­come.

In the 2020 - 2021 phase, more pro­duct­ive farms were es­tab­lished and dis­aster man­age­ment in case of losses was im­proved after the massive mor­tal­ity. In the sponge farm­ers' co­oper­at­ive, de­tailed op­er­at­ing reg­u­la­tions were in­tro­duced. New sponge farm­ers are already be­ing trained by the ex­per­i­enced farm­ers. Mar­ine­cul­tures.org mon­it­ors the pro­gress and only in­ter­venes where ne­ces­sary.

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