Pemba

MOZTIPA024
Pemba

Country: Mozambique

Administrative region: Cabo Delgado (Province)

Central co-ordinates: 13.1046 S, 40.54190 E

Area: 231km²

Qualifying IPA Criteria

A(i)Site contains one or more globally threatened species

IPA assessment rationale

The remnant pockets of natural coastal habitats within the Pemba Bay region and south to Mecúfi qualify as an IPA under criterion A(i). This site contains internationally important populations of 11 globally threatened plant species, five of which are assessed as Endangered and six as Vulnerable. Of these, Pemba IPA contains the total known global range of Eriolaena rulkensii (EN). As noted above, it may also contain Justicia niassensis (EN). The area is designated as an IPA in the hope that the small patches of intact coastal vegetation can be conserved and that degraded areas away from settlements can be restored such that its botanical importance can be protected and enhanced. Given the extent of fragmentation, the remaining areas of Rovuma Coastal Dry Forest are not considered to trigger criterion C(iii) at this site.

Site description

The Pemba IPA is located in Pemba, Metuge and Mecúfi Districts of Cabo Delgado Province. It comprises the coastal lowlands of Pemba Bay from Metuge southwards, parts of the Pemba Peninsula - excluding the urban and residential areas of the port city of Pemba, the capital of Cabo Delgado Province, and associated villages - and extending along the Indian Ocean coastline south towards the town of Mecúfi. The site contains a mosaic of terrestrial coastal habitats, much of which are heavily transformed but with some intact vegetation remaining. It also includes extensive mangroves in Pemba Bay. Although delimited as a single unit, with an area of ca. 231km2, only small and isolated pockets of this area are still of high botanical value. The inland boundary of this IPA is only vaguely delimited at present and may require future refinement.

Botanical significance

Although much of this IPA is heavily degraded and with large extents of the original vegetation now lost, it still contains a number of rare and threatened plant species within fragments of the original coastal vegetation of the proposed Rovuma Centre of Plant Endemism (Burrows & Timberlake 2011; Darbyshire et al. 2019a). Of primary importance, this site contains the entire known global population of Eriolaena rulkensii (EN), the only continental African member of this predominantly Asian genus. This is an attractive yellow-flowered shrub or treelet which occurs in heavy clay over coral-rag in coastal scrub and forest, sometimes at the upper margin of mangrove communities (Dorr & Wurdack 2018; Darbyshire et al. 2019b). This species occurs on the west (bay) side of the Pemba Peninsula and in remnant forest patches south of the peninsula towards Mecúfi. This latter area is also of importance for the rare endemic tree Acacia latispina (VU) which grows in open woodland on both dark clays and on gravelly and pebbly soils immediately behind coastal dunes. The habitat for the population between Pemba and Mecúfi is severely degraded due to wood-harvesting and overgrazing by cattle, although this species is able to withstand moderate habitat disturbance (Burrows et al. 2014a). Only the third known Mozambican site for the globally Endangered tree Hildegardia migeodii (EN) was discovered in 2012 on the Pemba peninsula. This IPA also holds some small populations of the Mozambican endemic tree genus Micklethwaitia carvalhoi (VU); these have been impacted by firewood cutting, but as this species does coppice well it can withstand heavy harvesting pressure (Burrows et al. 2014b). Pemba Bay holds an important population of the mangrove parasite Viscum littorum (NT) which grows here on both Sonneratia alba and Ceriops tagal; this species is endemic to northern Mozambique. In total, 11 globally threatened species have been recorded from the Pemba IPA, although the continued viability of some of these populations requires confirmation.
The Pemba Peninsula is one of only two known localities historically for the striking herb Justicia niassensis (EN), which was recorded near the lighthouse at Maringanha Point . However, the record at this site is from 1960, hence its continued presence on the peninsula requires confirmation given that much development has taken place in the meantime; the area in which this historic collection was made is not included within the IPA boundary but it is hoped that this striking species can be found elsewhere within the IPA in future.

Habitat and geology

The area supports a mosaic of habitats with much farmland and settlement. Away from the coast, the Pemba Peninsula and continuing southwards beyond Murrébue, the land rises rapidly to a low flat ridge up to 150 m asl., comprising iron-rich sandstones of the Mikindani Formation of mid-Neogene origin (ca. 10 – 15 mya). This rock gives rise to a coarsely sandy well-drained red soil. Elsewhere in Cabo Delgado, these Mikindani sandstones hold important areas of dry forest (Timberlake et al. 2010) but this whole area now is highly transformed and with no areas of forest remaining. Wild & Barbosa (1968) indicate on their vegetation map that this may have once supported Guibourtia schliebenii thicket (their mapping unit 14) but none of this remains. Elsewhere, the IPA is dominated by more recent Quaternary deposits including littoral dunes and recent alluvial deposits. Areas of heavy clay soils are found both around Pemba Bay and on the coastal lowlands between Murrébue and Mecúfi and these support an open Acacia-dominated woodland. There are also areas of raised coral rag which support a thicket vegetation. The south side of Pemba Bay supports extensive mangrove communities which are included in the IPA.
The coastline here has a highly seasonal humid tropical climate, with the wet season from December to April, usually peaking in March and with a prolonged dry season from May to November. Annual rainfall is ca. 870 mm at Pemba.

Conservation issues

This IPA is currently unprotected. Threats are considerable and varied, and large areas have already been heavily degraded or transformed. The Pemba Peninsula is impacted by continuing expansion of Pemba city and port. The population of this city is now over 200,000 and has more than doubled in 20 years. Further increases in population, at least in the short term, have resulted from displacement of populations from the north due to the recent violent insurgency. Away from urban areas, the major impact is from agricultural activity with extensive areas given over to growing crops and, particularly in areas of clay soils, high grazing pressure. Woody vegetation is also severely impacted by harvesting for charcoal and construction. The vegetation of the coastal fringe is being impacted by beach tourism; this is particularly prevalent at present on the Pemba Peninsula but it is also a threat to the less built-up coastline south of Murrubue towards Mecúfi (Darbyshire et al. 2019b). Regular flights now arrive into Pemba from Maputo and from South Africa, catering to wealthy tourists. Security issues associated with the insurgency to the north are impacting tourism in the short-term but this is likely to be only a temporary hiatus.
There is an urgent need to delimit and protect the remaining areas of natural vegetation and the surviving populations of the conservation-priority species within this IPA. One possible channel of support may be through Lúrio University which has a campus in Pemba with an active interest in biodiversity and conservation.
The Pemba IPA would qualify as an Alliance for Zero Extinction (AZE) site on the basis of Eriolaena rulkensii. It is not currently included within Mozambique’s Key Biodiversity Areas (KBA) network.

Ecosystem services

The remaining wild habitats within the Pemba IPA provide a range of important ecosystem services. The extensive mangroves in Pemba Bay are particularly important for prevention of coastal erosion, provisioning of materials for building and fuelwood, and provision of habitat for productive fisheries. Woodlands and bushlands provide a range of provisioning services including gathering of building materials and wild fruits. Wild habitats neighbouring agricultural areas also provide important habitat for pollinators of crops and for beekeeping. Finally, the natural habitats such as sand dunes and mangroves contribute to the touristic appeal of this area.

Site assessor(s)

Iain Darbyshire, Royal Botanic Gardens, Kew

Marcelino Inácio Caravela, Universidade Lúrio

IPA criterion A species

Species Qualifying sub-criterion ≥ 1% of global population ≥ 5% of national population 1 of 5 best sites nationally Entire global population Socio-economically important Abundance at site
Eriolaena rulkensii Dorr A(i) True True True True False Occasional
Vitex mossambicensis Gürke A(i) False True True False False Unknown
Vitex carvalhi Gürke A(i) False True True False False Unknown
Micklethwaitia carvalhoi (Harms) G.P.Lewis & Schrire A(i) True True True False True Occasional
Acacia latispina J.E.Burrows & S.M.Burrows A(i) True True True False False Occasional
Afrocanthium vollesenii (Bridson) Lantz A(i) True True True False False Unknown
Pavetta mocambicensis Bremek. A(i) True True True False False Unknown
Tarenna pembensis J.E.Burrows A(i) True True True False False Scarce
Justicia niassensis Vollesen A(i) False False False False False Unknown
Combretum caudatisepalum Exell & J.G.García A(i) True True True False False Unknown
Hildegardia migeodii (Exell) Kosterm. A(i) True True True False False Unknown
Oncella curviramea (Engl.) Danser A(i) False True True False False Unknown

Eriolaena rulkensii Dorr

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
True
Socio-economically important:
False
Abundance at site:
Occasional

Vitex mossambicensis Gürke

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

Vitex carvalhi Gürke

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

Micklethwaitia carvalhoi (Harms) G.P.Lewis & Schrire

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
True
Abundance at site:
Occasional

Acacia latispina J.E.Burrows & S.M.Burrows

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Occasional

Afrocanthium vollesenii (Bridson) Lantz

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

Pavetta mocambicensis Bremek.

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

Tarenna pembensis J.E.Burrows

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Scarce

Justicia niassensis Vollesen

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
False
1 of 5 best sites nationally:
False
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

Combretum caudatisepalum Exell & J.G.García

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

Hildegardia migeodii (Exell) Kosterm.

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
True
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

Oncella curviramea (Engl.) Danser

Qualifying sub-criterion:
A(i)
≥ 1% of global population:
False
≥ 5% of national population:
True
1 of 5 best sites nationally:
True
Entire global population:
False
Socio-economically important:
False
Abundance at site:
Unknown

IPA criterion C qualifying habitats

Habitat Qualifying sub-criterion ≥ 5% of national resource ≥ 10% of national resource 1 of 5 best sites nationally Areal coverage at site
Rovuma Coastal Dry Forest C(iii) False False False

Rovuma Coastal Dry Forest

Qualifying sub-criterion:
C(iii)
≥ 5% of national resource:
False
≥ 10% of national resource:
False
Areal coverage at site:

General site habitats

General site habitat Percent coverage Importance
Forest - Subtropical/Tropical Dry Forest No value Minor
Shrubland - Subtropical/Tropical Moist Shrubland No value Major
Savanna - Moist Savanna No value Major
Marine Intertidal - Mangrove Submerged Roots No value Major
Artificial - Terrestrial - Arable Land No value Major
Artificial - Terrestrial - Urban Areas No value Major

Forest - Subtropical/Tropical Dry Forest

Percent coverage:
No value
Importance:
Minor

Shrubland - Subtropical/Tropical Moist Shrubland

Percent coverage:
No value
Importance:
Major

Savanna - Moist Savanna

Percent coverage:
No value
Importance:
Major

Marine Intertidal - Mangrove Submerged Roots

Percent coverage:
No value
Importance:
Major

Artificial - Terrestrial - Arable Land

Percent coverage:
No value
Importance:
Major

Artificial - Terrestrial - Urban Areas

Percent coverage:
No value
Importance:
Major

Land use types

Land use type Percent coverage Importance
Agriculture (arable) No value Major
Tourism / Recreation No value Major
Industrial development No value Major
Residential / urban development No value Major

Agriculture (arable)

Percent coverage:
No value
Importance:
Major

Tourism / Recreation

Percent coverage:
No value
Importance:
Major

Industrial development

Percent coverage:
No value
Importance:
Major

Residential / urban development

Percent coverage:
No value
Importance:
Major

Threats

Threat Severity Timing
Residential & commercial development - Housing & urban areas High Ongoing - increasing
Residential & commercial development - Tourism & recreation areas Medium Ongoing - increasing
Agriculture & aquaculture - Annual & perennial non-timber crops - Small-holder farming High Ongoing - increasing
Residential & commercial development - Commercial & industrial areas Medium Ongoing - trend unknown

Residential & commercial development - Housing & urban areas

Severity:
High
Timing:
Ongoing - increasing

Residential & commercial development - Tourism & recreation areas

Severity:
Medium
Timing:
Ongoing - increasing

Agriculture & aquaculture - Annual & perennial non-timber crops - Small-holder farming

Severity:
High
Timing:
Ongoing - increasing

Residential & commercial development - Commercial & industrial areas

Severity:
Medium
Timing:
Ongoing - trend unknown

Management type

Management type Description Year started Year finished
No management plan in place No value No value

No management plan in place

Year started:
No value
Year finished:
No value

Bibliography

Darbyshire, I., Timberlake, J., Osborne, J., Rokni, S., Matimele, H., Langa, C., Datizua, C., de Sousa, C., Alves, T., Massingue, A., Hadj-Hammou, J., Dhanda, S., Shah, T. & Wursten, B., 2019

The endemic plants of Mozambique: diversity and conservation status

PhytoKeys, Vol 136, page(s) 45-96 Available online

Burrows, J.E., Timberlake, J., Alves, M.T., Coates Palgrave, F.M., Hyde, M.A., Luke, W.R.Q., Massingue, A.O., Matimele, H.A., Raimondo, D., Osborne, J. & Hadj-Hammou, J., 2014

Micklethwaitia carvalhoi. The IUCN Red List of Threatened Species 2014: e.T62494244A62494265.

Available online

Timberlake, J., Goyder, D., Crawford, F. & Pascal, O., 2010

Coastal Dry Forests in Cabo Delgado Province, Northern Mozambique: Botany and Conservation.

Burrows, J.E. & Timberlake, J.R., 2011

Mozambique’s centres of endemism, with special reference to the Rovuma Centre of Endemism of NE Mozambique and SE Tanzania.

South African Journal of Botany, Vol 77, page(s) 518

Burrows, J.E., Timberlake, J., Alves, M.T., Coates Palgrave, F.M., Hyde, M.A., Luke, W.R.Q., Massingue, A.O., Matimele, H.A., Raimondo, D., Osborne, J. & Hadj-Hammou, J., 2014

Acacia latispina. The IUCN Red List of Threatened Species 2014: e.T62494299A62494308

Darbyshire, I., Rulkens. T. & Rokni, S., 2019

Eriolaena rulkensii. The IUCN Red List of Threatened Species 2019: e.T134844673A134844770.

Dorr, L.J. & Wurdack, K.J., 2018

A new disjunct species of Eriolaena (Malvaceae, Dombeyoideae) from Continental Africa.

PhytoKeys, Vol 111, page(s) 11-16

Wild, H. & Barbosa, L.A.G., 1968

Vegetation map of the Flora Zambesiaca area (1: 250,000 scale). Supplement to Flora Zambesiaca.

Recommended citation

Iain Darbyshire, Marcelino Inácio Caravela (2024) Tropical Important Plant Areas Explorer: Pemba (Mozambique). https://tipas.kew.org/site/pemba-2/ (Accessed on 21/05/2024)