|The African Republic of Cape Verde consists of nine
inhabited and several uninhabited volcanic islands set out in the Atlantic
Ocean, about 500 km off the most westerly point of the African mainland and
1500 km south of the Canary Islands (Fig. 2).
Most are rugged and mountainous; three (Sal, Maio, and Boavista) are flat,
desert islands with sand beaches. Precipitation is meagre and very erratic;
indeed Cape Verde can be seen as an island extension of the arid Sahel zone.
Three species of the genus Phoenix are recorded from the Cape
Verde Islands, P. dactylifera L., P. canariensis Chabaud and
P. atlantica A. Chev. While the former two species have almost
certainly been introduced by man, the latter is said to be endemic to the
islands. Perhaps because the Cape Verdes are a particularly isolated set of
islands or because palms are notoriously awkward to collect, little is known
about the taxonomy, origins and natural history of this species.
Phoenix atlantica was described by the French botanist Auguste
Chevalier (1935a) following field exploration in the Cape Verdes in 1934
(Chevalier 1934: 1153). Chevalier provided limited diagnostic characters,
defining the species as a clustering palm with 2–6 trunks, 5–15 m in height
with dark green leaves 2–3 m in length. He considered it to be most similar
in form to P. dactylifera and P. canariensis, possessing
characters of both (Chevalier 1935a). Chevalier’s description indicates that
Phoenix atlantica can be distinguished easily from P. canariensis
by its clustering growth form (P. canariensis always has a
single, stout trunk) and its shorter, straighter leaves. However, the
differences between P. atlantica and P. dactylifera appear
much more subtle. For example, while P. dactylifera is usually
observed as single-stemmed, when left undisturbed for a number of years it
becomes clustering like the Cape Verde Phoenix, so this character on
its own is unreliable. Further alleged distinctions include acuminate (P.
atlantica) versus rounded (P. dactylifera) petals in the male
flowers (Chevalier 1935a, b, Greuter 1967: 249, and Brochmann et al. 1997),
fruit 2 cm long (P. atlantica) versus fruit more than 2.5 cm long (P.
dactylifera) (Brochmann et al. 1997), leaves green (P. atlantica)
versus leaves glaucous (P. dactylifera).
The somewhat ambiguous characters defined by Chevalier have raised
suspicions that Phoenix atlantica is not a distinct species. Barrow
(1998), in her monograph of Phoenix, suggested that it could be a
feral form of the date palm (P. dactylifera) or a product of
hybridisation and introgression between P. dactylifera and P.
canariensis. However, she was unable to resolve the question because the
material available to her was inadequate. The problem is intensified by a
lack of knowledge of the full extent of morphological variation in P.
dactylifera. Fortunately, genetic variation in Phoenix is being
investigated more fully at CIRAD (Centre de Coopération Internationale en
Recherche Agronomique pour le Développement) and IRD (Institut de Recherche
pour le Développement) in Montpellier (see also, for example, Trifi, Rhouma
& Marrakchi  and references therein), providing an alternative basis
for making comparisons with the Cape Verdean Phoenix.
With this in mind, a collaborative project was set up between The Natural
History Museum, London and Instituto Nacional de Investigaçao e
Desenvolvimento Agrário (INIDA), Santiago, with the aim of clarifying the
taxonomy of Phoenix atlantica using morphological and molecular
tools. The initial phase of the project entailed collection of primary data
– leaf material for DNA extraction, herbarium specimens, photographs and
ecological notes. After consulting literature and herbarium specimens for
collecting localities and flowering times, we arranged a field trip for May
2002. The four most easterly islands of Sal, Boavista, Maio and Santiago
“The neighbourhood of Porto Praya, viewed from the sea, wears a
desolate aspect. The volcanic fires of a past age, and the scorching heat
of a tropical sun, have in most places rendered the soil unfit for
vegetation. A single green leaf can scarcely be discovered over wide
tracts of the lava plains; yet flocks of goats, together with a few cows,
contrive to exist.” Charles Darwin (1845)
Charles Darwin’s first vision of Santiago in 1832 rings only too true
today. The island’s capital, Praia, has an undeniably West African feel –
lively markets flanked by roadside kitchens selling rice and bean stew for
breakfast, sweet sellers on the roadsides and shops in doorways.
Outside the city, heading up to the hills one travels through barren and
desolate land dotted with planted Prosopis juliflora (Fabaceae) and
the ubiquitous Calotropis procera (Asclepiadaceae). Near São Jorge
dos Orgaõs the higher elevations bring somewhat lusher vegetation and a more
tranquil atmosphere. Here, small numbers of Phoenix line the valleys
next to settlements, suggestive of their being planted, but they are
many-stemmed and at least superficially like P. atlantica.
Field work on Santiago centred around the area from which Chevalier’s
syntypes of Phoenix atlantica were collected, “around Praia and São
Martinho, near to the shore, at the edge of the valleys...” (Chevalier
1935b, translation) to the south of the island. The sites visited by us
(from west to east) were: Ribeira Grande, São Martinho (Pequeno and Grande),
Praia Baixo and São Francisco.
Passing through Cidade Velha, where the 16th century ruins of the old
capital of Santiago are found, we reached Ribeira Grande, a deep, lush
valley brimming with mango trees, coconuts and date palms. Here, we observed
numerous cultivated Phoenix including a striking individual, with
large plumose, glossy leaves and bright orange leaf bases. Around São
Martinho, the palms are mainly found in two spectacular, barren, dry river
valleys (ribeiras) known as São Martinho Pequeno and São Martinho Grande. A
handful of apparently untended Phoenix stand proud against the
landscape of rock and dust (Figs. 3–5). The
vast Phoenix populations at São Francisco extend from a dense,
managed grove into a population with a more natural appearance on the shore.
There is a striking morphological difference between the inland and the
coastal palms; moving away from the tall, archetypal palms inland onto the
dunes and the beach, we encountered remarkable stunted individuals,
many-stemmed and with short, glaucous leaves (Front Cover). These palms are
undoubtedly exposed to sea spray and some of those growing closest to the
shore may even experience salt water at their roots at high tides. Whether
or not they were originally natural, the Phoenix groves at Praia
Baixo, as at Ribeira Grande, are now quite obviously managed with some
clearly cultivated Phoenix seedlings, signs of irrigation, burning of
Prosopis and further plantings of coconuts and mangoes reinforcing
our convictions that these are agricultural systems, not natural
populations. In São Francisco and Ribeira São Martinho, however, the
distinction was far less obvious.
In Santiago began what we discovered to be extremely dusty work, often
made less appealing by rubbish left under the palms; in these relatively
populated areas the palm groves provide welcome shade for people and their
livestock. Phoenix is important to the Cape Verdeans in other ways;
leaves may be cut and used (sometimes sold) by villagers as thatch, fencing
or fodder for livestock. At some localities (e.g. Praia Baixo) the fruit is
apparently eaten by the locals while at others the fruit is fit only for the
goats. The best fruit is said to be traded throughout the islands.
Brief respite from fieldwork was provided in Ribeira Grande in the form
of locally produced grogue, a spirit made from sugar cane (grown in
the fertile valleys). Grogue is figuratively and literally a way of
life to many; not only is it an extremely popular drink on the islands, but
it is also produced on a small-scale by many farmers. Oxen or mules are used
to drive the trapiche, the machine which squashes the sugar cane. It
is said that the pressing of the cane, with its steady rhythm, has been a
strong source of inspiration for the famous Cape Verde music, although the
grogue itself has probably proved to be equally stimulating! The
hoteliers on the islands must have been surprised at our morning orders for
local grogue from the bar, but in fact we had found an alternative
use for it – for preserving Phoenix flowers.
All our herbarium material was prepared using the Schweinfurth method,
which involves pressing the specimens between newspaper before drenching
them in 70% alcohol and sealing them in robust plastic bags. At the end of
our fieldwork on Santiago, and indeed on the other islands, the bundles were
packed in boxes and posted back to the UK. Palm specimens can take a long
time to dry out, even using proper herbarium drying facilities, and if the
material is not processed properly, the fruit, flowers and leaves will rot.
Where drying facilities are not available, preservation in alcohol maintains
the quality of the plant material until further processing can take place
back in the herbarium. The processed collections have now been deposited in
the herbaria at INIDA, The Natural History Museum, London and the Royal
Botanic Gardens, Kew.
Our flight from Santiago to Maio lasted ten minutes, hardly worth the one
and a half hour check-in time! We were met and given a warm welcome by
Augusto Alves from the local office of the Ministério de Agricultura e
Peixes (Ministry of Agriculture and Fisheries). Augusto drove us into Vila
do Maio, the sleepy main town, flanked by a stunning beach of the whitest
sand and the most turquoise of seas. Here, young boys played among the
brightly painted fishing boats, crowding round to help the fishermen as they
came onto shore with their catch. On the street above the beach sat two or
three traders with trays of sweets or selling dark lumps of fresh tuna.
Women came and went from the town’s well, a place of great socialising,
balancing buckets of water on their heads.
So we embarked on a tour of the island in the Ministry’s 4WD vehicle. The
flatter parts of the island’s interior have been completely afforested with
Prosopis juliflora, creating the biggest Prosopis plantation
in the Cape Verde Islands. Plagues of locusts of near-biblical proportions
occur in the plantation, although, according to Augusto, the infestation is
not problematic. The new woodland is immensely important, although the
success of the afforestation programme comes at a cost as Prosopis is
notoriously water-greedy. The plantation was developed primarily to provide
fodder to livestock in the highly degraded landscape. In addition, the
timber from Prosopis is made into charcoal by the locals for use in
cooking and is also sold to other islands.
On the dunes at Morrinho, we spotted our first example of date palms on
Maio. Here, a handful of Phoenix grow in the blistering white sand
dunes, impressive in their stature and isolation, accompanied by an
occasional Tamarix bush and creeping Cyperus maritimus. The
dunes are bordered on one side by Praia de Santana, a stunning, but desolate
beach, and on the other by the salinãs (saltpans) of Terras Salgadas. The
saltpan at Morrinho is one of the few relatively undisturbed ecosystems left
on the Cape Verdes and is therefore under protection. The vegetation
consists of an expanse of salt-tolerant plants such as Arthrocnemum
glaucum (Chenopodiaceae), Zygophyllum fontanesii, the Cape Verde
endemic Asparagus squarrosus (dead but recognisable) and the
leafless, spiny Launaea melanostigma, resembling chicken-wire. Birds
abound in the saltpan and on the adjacent savanna-like plains; zebra finches
chirp en masse in Prosopis scrub and guinea-fowl scuttle around in
At the village of Pedro Vaz, to the east of the island, we came across a
large and ancient grove of Phoenix. The palms were majestic, despite
some being so old they had lost their crowns. There was no sign of any
Phoenix seedlings or juveniles here, an indication that the population
is not regenerating, hardly surprising as the pressure from goat grazing is
intense. One of the most striking palms at this site possessed around 15
stems and reached around 30 m in height, suggesting that it might be very
old indeed. After making some collections, we drove through the village of
Alcatraz towards Monte Penoso, a mountain, which, at 436 m, dominates the
otherwise flat landscape. Monte Penoso is an eroded volcano that is green in
the rainy season, hard to believe when the landscape appeared so infinitely
barren at the time of our visit.
At Lagoa, to the south of the island, we clambered down the sides of the
cultivated and relatively lush ribeira to sample a number of clustering
Phoenix. Scattered everywhere were rocks encrusted with Gastropod
fossils, evidence that Maio, while primarily volcanic, also has sedimentary
uplifts. Our search for Phoenix continued along the coast by Praia da
Lagoa, where we were presented with yet more stretches of sparkling seas and
shimmering sands. This walk was not to be blessed with Phoenix
discoveries, but we did make some other, serendipitous finds; a mass of
bifurcating, hollow, stony tubes poking out of the dunes – later identified
as fossil carbonate casts of tree roots – and remnants of a hammerhead
shark, sea turtles and whales strewn around the high tide mark.
We were greeted at the airport by an array of staff from the local
Agricultural Ministry, two of whom, Sonia Ramos Barros and Mario Spencer,
accompanied us on our fieldwork. Boavista is composed largely of immense
dunes stretching endlessly along the coast and inland. As our Twin-Otter
came in to land, we were treated with an astonishing early morning view of
the epic white sand dunes at Praia de Chave. Most striking of all though was
the glimpse of vast numbers of date palms extending throughout great inland
dunes beyond Chave. Around Sal Rei, thousands of Phoenix form what
appears to be a dynamic population of even age structure, with adults,
juveniles and even seedlings popping up spontaneously. We realised that we
had our work cut out here – a daunting prospect! In some areas, we noticed
many moribund Phoenix plants growing near to Prosopis (Fig.
6), presumably because the latter competes more effectively for water.
Mario drove us south to the pretty village of Rabil where we collected
yet more Phoenix from what appeared to be a plantation, and then
off-road into the Sahara-like interior of the island (Fig.
8). The Phoenix “populations” in the desert oases have also been
actively managed, sometimes growing with planted coconuts or tamarind trees.
They also appear more static than those around Sal Rei and, as on the other
islands, are composed of mature individuals only. We visited a small farm
adjacent to a Phoenix grove where a deep well provided enough water
for vegetables to be grown. On the edge of the smallholding, a few
magnificent specimens of Borassus aethiopum (Fig.
7) were found. The farmer could tell us nothing of the origins of these
undoubtedly ancient palms.
The monotony of the barren landscape was broken at intervals by hidden
treasures – a remote beach near Praia Santa Monica covered in crab-prints
and bordered by yet more Phoenix, the abandoned village of Curral
Velho, where bread ovens sat ruined and old cooking pots and limpet shells
lay scattered about the long-forgotten houses, the cracked salt crust of the
salinãs at Curral Velho with date palms towering on high coastal dunes
behind and frigate birds at Praia do Curral Velho (the only known breeding
site on the eastern Atlantic being the tiny islet found off this beach).
Beyond this, the rocky moonscape continued unabated, with blinding sun and
Sal is drab from the air and doesn’t improve much on the ground. It has
all the desolation, but few of the charms of the other islands. The land is
entirely uncultivated; even the goats are few in number. It is the oldest,
most eroded and most barren of all the islands. William Dampier, in 1683,
arriving on the isle of Sal from Virginia wrote:
“the land is very barren, producing no Tree that I could see, but some
small shrubby Bushes by the Seaside. Nor could I discern any Grass, yet
there are some poor Goats on it….There are no more than 5 or 6 Men on this
Island of Sall [sic], and a poor Governor…who came aboard our Boat, and
gave about 3 or 4 Goats for a Present to our Captain, telling him that
they were the best that the Island afforded.” William
Today, Sal’s main source of income is from tourism, centred on the small
town of Santa Maria. The seeds of tourism were sown in the 1960s when the
first small guest house was built in Santa Maria by the six mile beach.
Today, Santa Maria is a depressing contrast to the other places in which we
had stayed, the streets lined with restaurants and shops pandering to
European tastes, but the essence of Cape Verde culture still remains. Stray
only a few metres from the tourist route at night, to the backstreets of
Santa Maria, and the place becomes alive with countless hairdressers,
tuckedaway bars and grocers, and local people thronging the streets.
Sal may not be the most attractive of the islands visited, but it is
critical in terms of Phoenix; two of Chevalier’s P. atlantica
syntype localities are found here. The palms are neither as numerous as in
Boavista nor as majestic as in Maio. At the first syntype locality,
Algodeiro, we collected in the small, dense grove (Fig. 1) adjacent to a
beach with a remarkable salt-and-pepper blend of white shell sand and black
volcanic dust. The second syntype locality, Palmeira, allegedly named for
its abundance of palms, merely boasted a single stand in the middle of a
run-down suburb of the town. One of Chevalier’s specimens from Sal (26 June
1934, Chevalier s.n., P!) is annotated with the locality “Pedro Lime” – the
most similar placename today is Pedra de Lume, found about halfway up the
eastern coastline. An exploration of the area for Phoenix proved
fruitless, indeed we could see nowhere that even appeared to offer suitable
habitat, but the trip was fascinating for other reasons. High above the
village of Pedra de Lume is a salt lake inside the mouth of a long-extinct
volcano from which salt has been extracted for many centuries. The
architecture of the village serves as a reminder that this sleepy settlement
was once a hive of industry; the terraced houses are more reminiscent of
19th century industrial Britain than of anything we had seen so far on the
other islands. The salinãs themselves are set within the adjacent crater,
reached by a tunnel carved through the crater wall. The tunnel is found by
following the cables and wooden pylons of the old tramway that was used at
the peak of the production to transport salt from the crater to the port at
the village. Today, one passes through the mountain to the salinãs to find a
surprisingly silent and beautiful place, with regularly-spaced rectangular
ponds of pink, blue and white. The rusting machinery and rotting buildings
remain, the pulleys and tram-carts still visible, as if the whole industry
was stopped short and abandoned suddenly before the end of a day’s work.
Here in the salinãs we saw seven black-winged stilts, elegant, but
absurd-looking birds which appear to have the body of a gull and the legs of
a flamingo, and look altogether out of proportion. The redundant saltpans of
Pedra de Lume are of great environmental importance as Sal is the only
island in the Cape Verdes where these birds breed. Flamingos were also once
prevalent here; Dampier wrote about flamingos on Sal’s salinãs in 1698,
saying “Their tongues are large, having a large Knob of Fat at the Root,
which is an excellent Bit, a Dish of Flamingos’ Tongues being fit for a
Prince’s Table.” The bird of which he writes is the Rosy Flamingo which is
now extinct on the islands; their demise was probably encouraged by
Dampier’s party shooting 14 of them in one go.
We explored the eastern coast of Sal by 4WD from Pedra de Lume, returning
to the main road near Santa Maria. Finding yet more startlingly white sand
dunes and wind-blasted beaches, we failed completely to locate any more
Phoenix populations. A quest for another of Chevalier’s sites on Sal,
“Palha Verde,” (Chevalier 45840, 1934, P!) also proved difficult, as it was
not evident on any of the maps. After consulting a man selling salt crystals
at Pedra de Lume we drove to Fontona, an old settlement in a dry ribeira
just north of Palmeira, where we did indeed find a grove of around 200
Phoenix interspersed with a few coconut palms and Terminalia catappa.
Again, nearly all the Phoenix palms were clustering adults. Towards the
centre of the island, we identified a “new” locality for Phoenix (Fig. 9),
where around seven individuals grew in a dry ribeira. At Fenjaol, we
relocated another grove of around 150 Phoenix in a ribeira of blown
sand and one of only two sites where naturally-established seedlings were
observed. Perhaps the blown sand that covers the seed here and in the
population at Sal Rei on Boavista encourages germination by protecting the
seed from dessication?
Discussion and Conclusions
We observed some very striking populations of Phoenix in the Cape Verde
Islands, but through the course of the field trip we began to appreciate how
little the palms differed, if at all, from P. dactylifera. What is
intriguing about Chevalier’s observations is that he was able to distinguish
between Phoenix atlantica and P. dactylifera in the field.
Furthermore, of the islands we visited, he recorded P. dactylifera
from Santiago alone, from a palm grove near Praia (Chevalier 1935a, b),
suggesting that all other palms that we saw would have been P. atlantica
in Chevalier’s eyes. Not only this, in addition to “pure” P.
dactylifera and P. atlantica, he was able to identify hybrids of
the two near Praia in Santiago (Chevalier 1935a, b). There is no indication
as to how he determined these; certainly he made specimens neither of the
putative hybrids nor of P. dactylifera. We were unable to distinguish
the two species, let alone a hybrid.
Throughout the trip, we considered the distinguishing features specified
by Chevalier and subsequent authors discussed above. Nearly all the date
palms that we saw were multiple-stemmed, but this is a weak character, given
that P. dactylifera is inclined to cluster if unmanaged. None of the
Phoenix sampled bore fruit and therefore it was impossible to
evaluate fruit characters, though anecodotal evidence suggests that Cape
Verde Phoenix fruit is small, pink (to red) and often inedible.
However, as P. dactylifera cultivars display a vast range of fruit in
terms of colour, size, sweetness and shape (see for example Rhouma 1994),
the distinction in fruit size outlined by Brochmann et al. (1997) is
probably too simplistic.
Any difference in leaf colour is also observed with difficulty; it even
seems to vary within the same individual (the wax coating on leaves may vary
with age). However, the new collections will make possible a more thorough
investigation of the comparative leaf and floral morphologies in the
Whilst all species of Phoenix intercross freely (Wrigley 1995),
the suggestion that Cape Verde Phoenix may be a hybrid between P.
dactylifera and P. canariensis (Barrow 1998) now seems unlikely.
Chevalier (1935b) noted that Phoenix canariensis was occasionally
planted on Cape Verde and recorded it from the island of Sao Vicente, to the
west of the islands we visited. Despite our best efforts we failed to find
this species on Maio, Boavista, Sal or Santiago; perhaps it is cultivated on
some of the wetter islands to the west.
Until the taxonomy is resolved, the conservation status of this palm
cannot be assessed; for this very reason, Phoenix atlantica was
omitted from the most recent Cape Verde Red List (Leyens & Lobin 1996). This
study is further complicated by the claim that the species has been said to
exist further afield. Chevalier (1952) and Kunkel and Kunkel (1974) reported
it from the Canaries and Madeira (but see also Morici 1998) and Chevalier
(1952) described it from Senegal and Morocco (see also Munier 1973: 20). In
the same paper, Chevalier also described P. atlantica var.
maroccana A. Chev. which Barrow (1998) placed in synonymy with P.
dactylifera. These records are not particularly important in solving the
taxonomic conundrum of Phoenix in Cape Verde, but they do suggest
that a detailed, broad-scale assessment of the morphological and genetic
variation in P. dactylifera and its relatives across their range is
The need for a clarification of the taxonomy and conservation status of
Phoenix atlantica is obvious. Potentially, it is one of only two
endemic tree species in the Cape Verde Islands and one of only four palm
species native to Europe and Macaronesia. However, whether or not the Cape
Verde Phoenix proves to be distinct from the date palm P.
dactylifera, our observations suggest that it is of prime importance to
the people of the islands in terms of providing shade, food for livestock
and materials for building shelters. It also provides welcome relief for the
eyes in an otherwise highly degraded and seemingly endless, barren
Firstly, SH wishes to express her sincere gratitude to the Merlin Trust,
the International Palm Society and the South Florida Palm Society, whose
financial support made the trip possible. Thanks also to The Natural History
Museum and to the Royal Botanic Gardens, Kew (especially Dr John Dransfield)
for facilitating fieldwork. SH is also grateful to Dr Wolfram Lobin
(University of Bonn), Dr Teresa Leyens (Fogo) and Dr Estrela Figueiredo
(Lisbon) for all their advice and support prior to the trip. Special thanks
are due to Antonio Querido Director of the Instituto Nacional de
Investigação e Desenvolvimento Agrário (INIDA) and to the following staff of
the divisions of the Ministério de Agricultura e Peixes (MAP): Carlos Dias (Maio),
Augusto Alves (Maio), Francisca Duarte (Boavista), Sonia Barros (Boavista)
and Mario Spencer (Boavista) – their help and kindness proved invaluable.
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