Marine Cultural Heritage in Norther Mozambique – Wes Forsythe

Our Rising from the Depths project in northern Mozambique has been concerned with understanding the natural environment as a context for marine and underwater cultural heritage. A large dataset of geophysical survey results captured around Mozambique Island (Ilha de Mozambique) allows for new insights and features to emerge demonstrating the long history of sea-level change and its relevance for today’s communities in the context of climate change. In this blog we provide some of the first imagery derived from the survey work, which was conducted with colleagues from Centro de Arquelogia Investigção e Recursos da Ilha de Moçambique (CAIRIM) and the local community in Mozambique Island and marine heritage practitioners from the region.

Global sea level was -120m to -130m lower than present at the height of the last Ice Age (roughly 20,000 years ago) because vast quantities of ocean water were locked up in ice sheets. The coastal landscape inhabited by prehistoric people was therefore very different to today. Away from the large continental ice sheets the fall in sea level exposed large tracts of land, allowing rivers to cut across what is now the continental shelf and pushing coastlines out towards the shelf edge. Over time, global climate warmed, the ice melted and sea level rose. These landscapes, and any archaeological evidence they contained, were flooded and now lie on, or buried under the seabed.

Previous studies in Southeast Africa have identified remnants of these submerged landscapes. These types of evidence have been found off the KwaZulu Natal coast of South Africa and as far north as Maputo in southern Mozambique. The evidence includes former shoreline complexes, incised valleys and their sedimentary fills and shallow water/lagoonal sediments found at depth on the continental shelf.  The resulting evidence has also been used to provide insights into the timing, pattern and rate of the post-Ice Age sea-level rise. However, elsewhere on the East African coast, investigations of submerged landscapes and sea-level change are few and far between. The new evidence from northern Mozambique therefore represents a step towards filling this gap.

Consequently, the main aim of the December 2019 marine geophysical survey of Mozambique Island was to see if we could find any evidence of past sea level in this area. We chose to focus on two main areas. Firstly, the outer edge of the shelf fronting the Baie de Mozambique. Secondly, the channels which form the bay’s deeper entrances and allow access to the shallow waters behind the Island [1]. By using both multibeam echosounder (MBES) and sub-bottom profiler (SBP), we hoped to capture the geomorphic expression of relict landforms exposed on the seabed as well as features and stratigraphy which are currently buried under the seabed. The acquired data are still being analysed, but even so, a preliminary examination has been able to identify a number of features of geological and archaeological interest.

Our main area of MBES survey covered the outer shelf fronting the Baie, an area of ~13km². The resulting Digital Elevation Model (DEM) has a spatial resolution of up to 1m and shows a steep shelf which descends from ~-20m at the Baie entrance to almost -200m within a kilometre offshore. Several features of interest are visible on the MBES, the clearest being a narrow channel cut into the seabed between the Ile de Goa and Ile de Sena. At face value, this seems to provide a great example of a former river valley which was incised when sea level was lower [2]. Also apparent on the MBES are several submerged breaks in slope. The clearest one forms a distinct cliff line both north and south of the incised channel (but is absent in front of the channel). Where the base of the cliff is clearly visible, its depth is at ~-65m. At least two other low ridges/breaks in slope occur landward of the cliff line at depths of ~-35m to -40m. It is presently unclear whether these features represent former palaeo-shorelines. The depth of the submerged cliff line superficially matches palaeo-shoreline complexes (-60m) from KwaZulu Natal, but further analysis is needed to conform this. Fortunately, there was also enough time (and budget!) to acquire smaller patches of MBES around the northern end of the Ilha. These give glimpses of the inner parts of the Baie showing in particular the deeply incised nature of the channel between the Ilha and the mainland [3]. These data also captured some of the historic shipwrecks which are known to lie here and which will be the subject of future blog posts.

 

 

Meanwhile, SBP acquisition was arranged to give a series of profiles running offshore from the coast to the shelf edge and across and along the channels. These were sited to establish the wider stratigraphic sequence and provide targeted data over the channels which could demonstrate how they responded to sea-level change. Starting with the outer shelf, the SBP profiles clearly show that the channel visible on the MBES is actually incised to a considerable depth below the seabed and was later infilled [4]. In fact, the SBP data also show that it extends seaward of its surface expression as a completely infilled valley. The SBP data also confirmed the existence of the distinct cliff line on the outer shelf, and also suggests that its base is buried, and in some cases there may also be a deeper buried break in slope at ~-92m [5]. In the outer part of the Baie, channels are also clearly visible on the SBP data, incised below the seabed and subsequently infilled [6]. In all cases, the nature of these infills requires further analysis. Other potential features of interest include terraces cut into the flanks of the channels and secondary channels paralleling the main channel [6]. Finally, the stratigraphy becomes more complex in the inner part of the Baie behind the Ilha. Whilst the seabed surface appears to be relatively undulating, the SBP results show a more rugged, buried topography. These include high points with an acoustic character suggestive of reefs and basins which have been infilled by horizontal or gently-dipping layers sediment, possibly suggestive of deposition in lagoonal or sheltered water conditions.

 

 

All the above is still work in progress, with interpretations to be confirmed by additional processing and analysis. However, even this preliminary glimpse has shown us the potential of these data to contribute to our understanding of sea-level change and palaeo-landscape evolution on the coast of East Africa. The survey work will form a component of the training on the tools and techniques used being delivered to the community on the Ilha and will inform new exhibition materials for the CAIRM facility on the island.

Caesar Bita – MUCH to Discover in Mida Creek

Our MUCH project continues to attract greater attention. A national fundiing organization / Network called NETFUND (Environment Trust Fund (NETFUND) have expressed interest to support our project. Yesterday their officers visited Mida MUCH to explore areas we can collaborate. This is indeed great.

NETFUND is a State Corporation established by the Environmental Management and Coordination Act of 1999. Our mandate is “To facilitate research intended to further the requirements of environmental management, capacity building, environmental awards, environmental publications, scholarships and grants”. NETFUND’s vision is “Sustainable financing available for environmental management in Kenya”. Our mission is “To mobilize, manage and avail resources for; environmental awards, capacity building, research and publications, scholarships and grants.

Mark Lamont – MUCH to Discover in Mida Creek

 

Inter–tidal ‘wreck’ survey in Mida Creek

Many disused boats can be found hauled up onto the beaches of Kenya’s Indian Ocean coast. These are testimonies to the coast’s rich maritime cultural heritage, but their potential value to local communities has been largely overlooked. Although they are no longer being used for transportation, fishing, or hauling cargo, such vessels remain part of the region’s heritage and can be a diverse source of value.

MUCH to Discover in Mida Creek commissioned a survey in May 2019 to create an interactive map of the ‘wrecks’ within the creek’s inter-tidal areas. One purpose of this mapping exercise was to document the kinds of marine vessels used throughout Mida Creek’s tidal channels. Another reason for carrying out this map of disused boats was to create a record in light of ongoing purchases of such ‘abandoned’ boats for the purpose of making furniture and other objects for sale in the tourism industry. From many places along the East African coast where there is a significant tourist economy, a new taste for chairs, mirror frames, and other kinds of furnishings made from disused, beached vessels has created a market for this heritage.

 

In the shadow of the dhow

Boat building and maintenance is characteristic mark of a maritime culture (Prins 1965). The iconic ‘dhow’ is a symbol of Swahili maritime culture par excellence. Dhow building and sailing has occupied academic interests and continues to drive significant debate about the Indian Ocean world, its histories, its global connections (see Gilbert 2004; Sheriff 2010; Prins 1965; Villiers 1940). Indeed, Lamu’s Dhow Festival is testimony to the allure of these large ocean- going vessels among local peoples and foreigners alike. Yet resting in the shadows of such larger vessels are the many different kinds of smaller boats. This mapping exercise sought to draw attention to the significance of small maritime craft used for inter-tidal or inshore fisheries and transportation. It was hoped that MUCH to Discover in Mida Creek might inspire visitors to participate in the living traditions of the creek’s communities, including boat- building, taking a trip in such boats, as well as contributing to an online project of documenting ‘wrecks’ as artefacts of significant historical and cultural value.

 

Mida Creek Boat Map

Visitors to the MUCH to be Discovered at Mida Creek project will be invited to ‘see’ the maritime cultural heritage as they move around the creek and its channels. A Google Earth Project, the Mida Creek Boat Map, can serve to guide visitors around the various sites, most of which are fishing villages or landing sites.

You can access the site here.

Mida Creek’s vessels in context

Mida Creek is currently situated within three important gazetted areas: (1) Watamu National Marine Park; (2) Arabuko-Sokoke Forest; and (3) Gede National Monument. Restrictions in economic activities apply to all of these sites. The creek itself is part of a bio-sphere reserve and certain restrictions are in place on how local residents may use their natural resources.

Fisheries continue to be a significant, although threatened, resource for making a living. Small dugout canoes, mtumbwi (or dau as they are known locally) are all-purpose boats for most inter-tidal fisheries and, on occasion, for ferrying visitors to sites of special interest in the creek. The boat-building activities that took place with this project in 2019 were commissioned to build new mtumbwi that visitors can experience.

Mtumbwi – dugout canoes made from mwembe wood (mango) trees, or msufi (kapok), used extensively in the inter-tidal zones of the creek. They are propelled, or punted, through the water using poles (kafi).

Hori – a variation on the mtumbwi (dau) but used to move between the shore and larger vessels at anchor. Note that only one example of this was found during the survey, but presumably during the active years of the mangrove trade, these would have been numerous.

Ngalawa – this outrigger canoe was used for littoral transportation, as well as for reaching outlying reefs for spear and net fishing. There was one ngalawa found during the survey at Uyombo. They are popular among tourists for local excursions under sail.

Mashua – these are the smaller of the iconic lateen sail ‘dhows’, mainly used for fishing on the ocean for pelagic fish, sharks, and snapper; and/or for transport of cargo from port to port.  Fishermen  could  live  aboard  these  craft and  they  are  used  in  coasting very long distances.

Boat-sheds

The saline and coralline environments takes a toll on wooden boats. While these vessels are mainly made from mango wood or mwembe, as well as msufi (kapok, or cotton-tree), the availability and costs of this wood has become a challenge for most craftsmen. As boat- maintenance has been changed by the availability of new materials and techniques, the

‘fibreglass revolution’ within boat-building traditions has been applied also to repairing these smaller inshore and inter-tidal craft. Most significant landing sites near villages in the creek have boat-sheds  constructed  of straight mangrove poles (boriti) and  palm-frond thatch (makuti) to provide craftsmen and their assistants with shelter and shade while they are working. The MUCH to Discover in Mida Creek ‘dhow-house’, where experimental archaeology activities will take place, is an example of this local, indigenous architecture.

 

Conclusions

Until there is a wide understanding that small inter-tidal and inshore boats are of significant cultural heritage value, their looting will continue. As such boats become replaced by fibreglass vessels, some of their unique manoeuvrability and handling in sheltered, inter-tidal channels will surely be lost. Boats like mtumbwi are perfectly adapted to reach deep inside tidal mangrove channels to exploit resources only found there. Whether it is fishing or taking tourists into the mangrove, such vessels are an important, central part of the maritime cultural heritage of the creek’s communities.

By creating a map of the existing disused boats, MUCH to Discover in Mida Creek creates an opportunity for local people to document the stories of each of these boats. The hope is that an intriguing record of mtumbwi, hori, ngalawa, and the larger mashua will inspire new research and programming into Mida’s fascinating maritime traditions. Not only will an interactive map bring about a record of such boats locations, it also curates them digitally and may start a process whereby local fishermen and their owners value them for something other than the small amounts of money that collectors or looters will pay for them. A map can educate school children, as well as being a source of potential fun as they explore other aspects of the creek’s rich marine and maritime heritage. As biocultural artefacts, such boats tell an interesting story about the special adaptations and history of Mida Creek within a wider world.

 

Suggested and Further Reading:

• Falck, W. E. (2014). Boats and Boatbuilding in T anzania (D ar-es-S alaam and Zanzibar). International Journal of Nautical Archaeology, 43(1), 162-173.
• Gilbert, E. (2011). The dhow as cultural icon: heritage and regional identity in the western Indian Ocean. International Journal of Heritage Studies, 17(1), 62-80.

• Gilbert, E. (2004). Dhows & the colonial economy of Zanzibar: 1860-1970. Oxford: James Currey.

• Pollard, E., & Bita, C. (2017). Ship engravings at Kilepwa, Mida Creek, Kenya. Azania: Archaeological Research in Africa, 52(2), 173-191.
• Prins, A. H. J. (1965). Sailing from Lamu: a study of maritime culture in Islamic East Africa.
• Sheriff, A. (2010). Dhow Culture of the Indian Ocean: Cosmopolitanism, Commerce and Islam. Columbia University Press.

• Villiers, A. (1940). Sons of Sinbad: An Account of Sailing with the Arabs in Their Dhows, in the Red Sea, Round the Coast of Arabia, and to Zanzibar and Tanganyika, Pearling in the Persian Gulf, and the Life of the Shipmasters and the Mariners of Kuwait. Hodder & Stoughton.
• Weiss, E. A. (1973). Some indigenous trees and shrubs used by local fishermen on the East
• African Coast. Economic Botany, 27(2), 174-192.

Marine Cultural Heritage in Northern Mozambique 

Northern Mozambique formed part of the Indian Ocean trade network from the 7th century, which gave rise to a vibrant maritime culture of settlement, travel and exchange. The most well-known site is Mozambique Island, a major port of significance for East African maritime trade from the 14th century. It became the capital of Portuguese colonial government from 1507 and its architectural diversity was recognised by UNESCO World Heritage Site designation in 1991. Despite the wealth of archaeological sites located in the waters around the Island, Marine Cultural Heritage (MCH) has not received the attention and protection it deserves. Pressures on the resource have ranged from damage by salvage operations, insensitive development, to poor fishing practises and pollution.

In response the Centro de Arquelogia Investigção e Recursos da Ilha de Moçambique (CAIRIM) is vitally important in providing a focus for the study and conservation of marine cultural heritage on the island and for efforts to reach and engage with the local community. An initiative of Eduardo Mondlane university, CAIRIM has been a key partner of the Northern Mozambique project as it develops new ways of exploring, understanding and celebrating Marine Cultural Heritage.

One such effort to develop new dimensions for MCH is a major campaign of underwater survey touching on themes hitherto unexplored in the region. The Mozambique coast is little studied from a coastal geomorphology perspective and very little baseline information exists on fairweather processes, storm impacts, or sea-level change, all of which shape the landscape and influence livelihoods. The coast and continental shelf contain important indicators of past sea- levels, including former shorelines now submerged. The nature of the geomorphic record provides indications of coastal response to former sea-level change and, taken in conjunction with the contemporary coastal morphology and projected future sea- levels, provides an insight into likely future conditions and the challenges they pose to inhabitants, the local economy and the cultural and biological heritage.

Toward the end of 2019 we deployed a range of geophysical equipment in the waters adjacent to the island. In total over 100km of seismic data and c.25ha of multibeam sonar imagery were collected. The seismic technique is capable of penetrating the seabed and thus detecting buried features that reveal the changes to the environment, for example former river channels which were submerged by sea-level rise and now infilled with sediment. The multibeam sonar measures depth with great accuracy enabling a high-resolution 3D model of the seabed to be produced which includes natural and cultural points of interest. Mozambique Island lies within a large, shallow embayment with deeper channels approaching its anchorage to the north. These exit into the Indian Ocean where the bathymetry deepens swiftly at a submerged shelf that runs parallel to the East African coast. Work concentrated on this area of the shelf which can reveal ‘terraces’, palaeo-channels and other relic geomorphological features suggesting the presence of earlier shorelines and former landscapes under lower sea-level conditions.

Survey data is still under analysis and will form a key element of the training and materials the project will be delivering on its return to Mozambique Island. The survey team’s field visit coincided with a UNESCO training workshop hosted by CAIRIM on the Island. This allowed not only CAIRIM personnel and community volunteers to join the survey vessel but also maritime cultural heritage practitioners from the wider region. In addition, we joined the workshop back at base to deliver training insights on the geophysical techniques employed and their display and interpretation. Once all data is processed a further set of interpretative and training materials will be developed to conclude the surveys findings.

As fascinating as the emerging survey results are, they are not undertaken in isolation of the broader aims of contextualising past climate change in order to meet the challenges of current sea-level threats and other pressures. The project’s return to the island was disrupted by the COVID-19 crisis, however this involves an ongoing programme of training, community engagement and ethnographic survey. In addition work in partnership with CAIRIM will involve returning to shipwrecks imaged during the survey in order to enhance our understanding of them and assess their vulnerability.