Species occurrence of cetaceans in Guinea, including humpback whales with southern hemisphere seasonality

An initial inventory of the dolphins and whales occurring in Guinea's coastal waters is documented primarily from specimens and photographic evidence obtained from strandings and by-catches. Seven species are fully validated, four odontocetes, Tursiops truncatus, Sousa teuszii, Stenella frontalis, Kogia breviceps and three balaenopterid whales: Balaenoptera brydei, Balaenoptera acutorostrata and Megaptera novaeangliae. Another three reported species (Globicephala macrorhynchus, Steno bredanensis and Delphinus delphis) are insufficiently supported but thought to be valid. Small cetaceans landed as by-catch and a stranded whale were used for human consumption, but no evidence of substantial takes, directed or by-catch, was found. However, concern is raised about even minimal takes of the vulnerable Atlantic humpback dolphin. The seasonal presence of three confirmed humpback whales, two strandings (July and September) and a sighting (October), is synchronous with the species' southern hemisphere wintering/breeding season in low latitudes. We hypothesize that these whales may comprise the north-westernmost range of the population that breeds/overwinters in coastal waters of the Bight of Benin, northern Gulf of Guinea

The cetaceans of Guinea, a first check-list of documented species. Scientific Committee document SC/58/O15, International Whaling Commission, May-June 2006, St. Kitts

A CMS workshop on West African Cetacea (Conakry, May 2000), called for i.a. ‘carrying out .. inventory of cetacean species; collection, treatment and compilation of data for each state.’ The present paper is a preliminary faunal checklist of cetaceans occurring in Guinea’s EEZ. Information was gleaned from strandings, bycatches, scientific and opportunistic sightings and a literature review. Ten species are included for which supporting voucher material and data were available for examination. These are, three baleen whales: Balaenoptera brydei, Balaenoptera acutorostrata and Megaptera novaeangliae; and seven species of odontocetes: Kogia breviceps, Tursiops truncatus, Sousa teuszii, Stenella frontalis, Delphinus delphis, Steno bredanensis and Globicephala macrorhynchus. Another two species, Physeter macrocephalus and Stenella attenuate were sighted off Guinea but no photographic evidence was obtained. The current account is thought to reflect an incomplete picture of Guinea’s cetacean biodiversity. Future surveys are expected to update and investigate spatial and temporal distribution patterns for each species along Guinea’s coast. A few bycatches landed by artisanal fishers were utilised locally, but there are no signs of any substantial captures. Nonetheless, monitoring should be continued. The set-up of a national reference collection and database is recommended. The population identities of the encountered Atlantic humpback dolphin, minke whale and humpback whale are of particular interest

Indeterminate status of West African populations of inshore common bottlenose dolphins <i>Tursiops truncatus</i> caution against opportunistic live-capture schemes

The limited information available on the status of inshore common bottlenose dolphins Tursiops truncatus along the coasts of West Africa is reviewed. Although reported from at least ten countries, it is unclear whether their distribution is continuous. Population structure and genetics have not been studied, however cranial morphology suggests that the West African dolphins differ from North Sea bottlenose dolphins. Mean group sizes are small (3.19 – 12.91 individuals/group) and are smallest in Guinea-Bissau. There are no estimates of abundance but by analogy with a well-studied population in Sarasota, Gulf of Mexico, the Guinea-Bissau population may number only in the hundreds. It is essential that scientific estimates be obtained through dedicated surveys. In some areas of Guinea-Bissau with a high density of fishing activities, bottlenose dolphins are now less frequently encountered than they were in the recent past. Key parameters besides abundance, including population identity, bycatch levels and other anthropogenic threats need to be documented and quantified before any deliberate exploitation is considered. A small-scale, botched live-capture operation in Senegal in 2003, in which all dolphins died, serves as warning against such opportunistic schemes. In management terms, live-capture operations are equivalent to hunting and multi-year, large-scale removals of bottlenose dolphins in Guinea-Bissau would have the potential to effectively extirpate the wild population from its waters

New records of Atlantic humpback dolphin in Guinea, Nigeria, Cameroon and Togo underscore fisheries pressure and generalised marine bushmeat demand

In northern Guinea, we sighted two groups of Sousa teuszii (n=25; n=40 dolphins) off the Tristao Islands during exploratory small-boat surveys in 2011-12. Based on these and recent (2013) observations in the contiguous Rio Nunez estuary, we propose a single 'Guineas stock', combining the former 'Canal do Jeba-Bijagos' and South Guinea stocks. Significant mortality of S. teuszii from fisheries interactions is widely recognised however not quantifiable as monitoring effort is sporadic. In Guinea, catches were documented in 2002 (n=1) and in 2011-12 (n=5). Landed specimens were recorded in Cameroon (n=2) and Nigeria (n=2). All individuals were killed in small-scale coastal fisheries, presumably as accidental net entanglements, though directed takes cannot be excluded. All landed dolphins were butchered for human consumption (marine bushmeat). Nigerian fishers indicated also an alternative use as shark bait. If local markets in cetacean bushmeat and bait develop, as in Ghana, that will exacerbate pressures by encouraging directed takes. Catch records in Nigeria and sightings in Togo authenticate both nations as (long-suspected) range states for S. teuszii, a belated documenting of the primary, historical distribution. The Gulf of Guinea stock ('Cameroon dolphins') extends at least from Togo to southern Cameroon, and probably into Equatorial Guinea. However, rare sightings of small groups point to remnant, not thriving, dolphin communities. We anticipate de novo distribution gaps emerging and consolidating, following decades of fisheries interactions and creeping encroachment on once pristine coastal habitat. Developed coastlines in Ghana and Cote d'Ivoire devoid of records may already constitute such gaps. As the lack or scarcity of records warn about formidable challenges to the long-term survival of S. teuszii, innovative, workable protection measures are needed, soonest. We recommend the implementation of several new border-straddling marine protected areas (cf. Saloum Delta-Niumi National Park Complex) which could bring forth a major conservation effect. Binational involvement bears obvious advantages, from sharing responsibilities and allowing for larger protected areas. Suggested dolphin sanctuary examples could include MPAs straddling borders between Cameroon/Equatorial Guinea and Guinea-Bissau/Guinea-Conakry

Spatial Environmental trends in the three Atlantic African Large Marine Ecosystems in a context of global warming

ICAWA : International Conference AWA, Lanzarote, ESP, 17-/04/2018 - 20/04/2018In Atlantic Africa there is a crucial need to better assess the effect of climate change on marine ecosystems, particularly over the continental shelf and inside the national exclusive economic zones. Nevertheless there is a lack of observation carried out in the African ecosystems and the times series are often short or disrupted. Space-based observations allow precise synoptic observation of marine ecosystem and is often use to monitor, e.g., Eastern boundary upwelling ecosystems, from 36 years of constant monitoring from some major parameters as Sea Surface Temperature and more than twenty years for Ocean-Colour related parameters as surface primary productivity. The spatially heterogeneous trends observed show that these systems are highly variable, at temporal scales decades) that potentially impact some of their marine resources at rates that compete with the decline of human activities, beyond over-fishing. In this work we will present the effect of global warming at regional level for the three large marine ecosystems of Atlantic Africa on the sea surface temperature, wind stress and chlorophyll concentration as a proxy of primary production. The Canary and the Benguela systems are particularly impacted by the global warming, especially in their tropical parts, while Pacific systems show a more stable trend, due to their constantly high activity that partly counteracts some effects of the global warming

International conference ICAWA 2017 and 2018 : extended book of abstract : the AWA project : ecosystem approach to the management of fisheries and the marine environment in West African waters

In Atlantic Africa there is a crucial need to better assess the effect of climate change on marine ecosystems, particularly over the continental shelf and inside the national exclusive economic zones. Nevertheless there is a lack of observation carried out in the African ecosystems and the times series are often short or disrupted. Space-based observations allow precise synoptic observation of marine ecosystem and is often use to monitor, e.g., Eastern boundary upwelling ecosystems, from 36 years of constant monitoring from some major parameters as Sea Surface Temperature and more than twenty years for Ocean-Colour related parameters as surface primary productivity. The spatially heterogeneous trends observed show that these systems are highly variable, at temporal scales decades) that potentially impact some of their marine resources at rates that compete with the decline of human activities, beyond over-fishing. In this work we will present the effect of global warming at regional level for the three large marine ecosystems of Atlantic Africa on the sea surface temperature, wind stress and chlorophyll concentration as a proxy of primary production. The Canary and the Benguela systems are particularly impacted by the global warming, especially in their tropical parts, while Pacific systems show a more stable trend, due to their constantly high activity that partly counteracts some effects of the global warming

Distribution, status, and biology of the Atlantic Humpback Dolphin, <i>Sousa teuszii</i> (Kükenthal, 1892)

The distribution, status, and biology of the Atlantic humpback dolphin (Sousa teuszii) is critically reviewed, and results of recent research are discussed. The species’ known distribution limits are, in the north, Dahkla Bay (23º50’N), Western Sahara, and in the south, Tombua (15º47’S), southern Angola. Its habitat is predominantly inshore coastal and estuarine, over soft-sediment bottoms. There is no evidence that it might occur beyond the brackish waters of estuaries into a riverine, fresh-water habitat. There are no records for the Senegal, Casamance, and Niger Rivers. A total of eight stocks are provisionally discerned for management purposes. Six of these are confirmed-contemporary (based on recent records), including Dahkla Bay, Banc d’Arguin, Saloum-Niumi, Canal do Gêba-Bijagos, South Guinea, and Angola. Two stocks, the Cameroon Estuary and Gabon, are historical, and new fieldwork needs to confirm their current presence. No inference is made on degree of reproductive isolation and biological population status of any named stock. The potential existence of a western Togo stock is currently under study. Nine coastal states, including Morocco (Western Sahara), Mauritania, Senegal, The Gambia, Guinea-Bissau, Guinea- Conakry, Cameroon, Gabon, and Angola are confirmed range states. While historically distribution may have been quasi-continuous over the species’ range, indications of contemporary distribution gaps are emerging. Ongoing monitoring of cetacean takes in coastal fisheries off western Ghana, and experimental whale-watching sorties in Bénin have not yielded a single record. The species has either become rare through human-related pressures or, less likely, it never lived there. For most other areas there is little, if any, information due to the lack of research

The interest of smartphone use for field Fisheries and marine environmental sciences surveys in West Africa : a demonstration project AWAphone [résumé]

ICAWA : International Conference AWA, Dakar, SEN, 13-/12/2016 - 15/12/2016Data collection in fisheries and environmental sciences all over the world remain often difficult and expensive and particularly in low income countries as it is the case in West Africa. The national fisheries center have a regal mission to collect fisheries data and all other information relative to the marine environment. For such purpose all the fisheries center get numerous agents spread all along the coastline in the main national landing sites. The smartphone now get an impressive processing capacity and thus can do numerous tasks which were before limited to computer users, but also allow mobility in the field. The application developed for smartphone can now be easily developed and even delivered in open access. To take advantage of such technological progress well assimilated in West Africa (smartphone are now usual in West Africa) we have make some trials. The main interest of smartphone appear to be the data acquisition, monitoring and transfer (e.g ODK application) in near real time particularly for regular fisheries statistics in main landing sites and field interviews. Such method avoid errors during manual data acquisition and allow fast analysis. A side several of information have been collected during the trials as medusa and algal blooms, and stranding of fish or mammal as whales as well as turtle egg-laying but also extreme event as coastal erosion after a storm (e.g. ravage application; Cerema). These information/reports take advantage of spatial localization using GPS option. Obviously, fish species identification during data collection could be validated with remote expert and e.g. INRH have already developed an application (Guide des poissons du Maroc) for fish identification of main exploited fish species. Moreover, the fisheries center agents can inform on fishing interferences as well as illegal activities. We recommend the equipment of the fisheries agents with the development of regional ad hoc applications and procedures of data collection knowing that numerous others new applications of great interest for fisheries center in West Africa, will be found. Lastly, the smartphone can be associated to physic and chemical sensors to allow to upload and transfer data to the research center data center at low cost, quickly and foster collaborative action with civil society

The interest of smartphone use for field Fisheries and marine environmental sciences surveys in West Africa : a demonstration project AWAphone [résumé]

ICAWA : International Conference AWA, Dakar, SEN, 13-/12/2016 - 15/12/2016Data collection in fisheries and environmental sciences all over the world remain often difficult and expensive and particularly in low income countries as it is the case in West Africa. The national fisheries center have a regal mission to collect fisheries data and all other information relative to the marine environment. For such purpose all the fisheries center get numerous agents spread all along the coastline in the main national landing sites. The smartphone now get an impressive processing capacity and thus can do numerous tasks which were before limited to computer users, but also allow mobility in the field. The application developed for smartphone can now be easily developed and even delivered in open access. To take advantage of such technological progress well assimilated in West Africa (smartphone are now usual in West Africa) we have make some trials. The main interest of smartphone appear to be the data acquisition, monitoring and transfer (e.g ODK application) in near real time particularly for regular fisheries statistics in main landing sites and field interviews. Such method avoid errors during manual data acquisition and allow fast analysis. A side several of information have been collected during the trials as medusa and algal blooms, and stranding of fish or mammal as whales as well as turtle egg-laying but also extreme event as coastal erosion after a storm (e.g. ravage application; Cerema). These information/reports take advantage of spatial localization using GPS option. Obviously, fish species identification during data collection could be validated with remote expert and e.g. INRH have already developed an application (Guide des poissons du Maroc) for fish identification of main exploited fish species. Moreover, the fisheries center agents can inform on fishing interferences as well as illegal activities. We recommend the equipment of the fisheries agents with the development of regional ad hoc applications and procedures of data collection knowing that numerous others new applications of great interest for fisheries center in West Africa, will be found. Lastly, the smartphone can be associated to physic and chemical sensors to allow to upload and transfer data to the research center data center at low cost, quickly and foster collaborative action with civil society