Time filter

Source Type

Van Waerebeek K.,COREWAM Senegal | Van Waerebeek K.,Peruvian Center for Cetacean Research | Djiba A.,COREWAM Senegal | Djiba A.,Cheikh Anta Diop University | And 3 more authors.
African Zoology | Year: 2013

Seventeen confirmed and four probable sightings of humpback whales, Megaptera novaeangliae, were documented from platform-of-opportunity Research Vessel (R/V) Dr. Fridtjof Nansen in a passing-mode visual survey of continental shelf waters between Conakry and Cap Vert Peninsula (Dakar), 21 October -5 November 2011. None were encountered in the northern stratum Dakar-Agadir, 6 November -15 December 2011. Total visual survey effort was 468 h, 01 min, covering 5335 km. Depending on the exclusion or inclusion of probable records, the sum of group sizes totalled 33 or 43 individuals, respectively. Humpback whale encounter rates between Conakry and Dakar then amounted to 1.74 or 2.27 whales/ 100 km, respectively. Group sizes ranged from 1-6 individuals (mean = 1.94, S.D. = 1.20, n = 17; median = 2). Minimally five of 17 groups (29.4%) consisted of adult-calf pairs, with a minimum crude birth rate ranging from 0.060-0.152. All sightings occurred in shallow water, 22-60 m (mean = 35.0 m, S.D. = 10.13, n = 17) but survey effort in deeper, offshore water was negligible. Sea-surface temperature at sighting locations ranged from 25.5-29.0°C (mean = 27.34, S.D. = 0.96, n = 17). No humpback whales were sighted during a second survey covering Conakry-Tangier-Las Palmas, from 9 May to 22 July 2012 (519 h, 13 min; 6278 km). The Cape Verde Islands comprised, to date, the only known wintering ground located in the North-East Atlantic. This study showed that Senegal, The Gambia, Guinea-Bissau and Guinea are normal range states for M. novaeangliae. A temporal signature, six to seven months out-of-phase with mid-season in the Cape Verde Islands, and neonate presence strongly suggest that the wide Conakry-Dakar continental shelf serves as both wintering and nursery grounds for a South Atlantic stock, in agreement with Bamy et al. (2010). This stock may comprise the northwesternmost component of the large humpback whale assemblage migrating in and out of the northern Gulf of Guinea in austral winter/spring. Further research is required to consolidate insights linking temporal and spatial distribution off western Africa with hemispheric stock identity and migration paths.


PubMed | Wildlife Conservation Society, Federal University of São Carlos, Peruvian Center for Cetacean Research, Southwest Fisheries Science Center and Centro Ballena Azul Blue Whale Center
Type: | Journal: Molecular ecology | Year: 2016

Many aspects of blue whale biology are poorly understood. Some of the gaps in our knowledge, such as those regarding their basic taxonomy and seasonal movements, directly affect our ability to monitor and manage blue whale populations. As a step towards filling in some of these gaps, microsatellite and mtDNA sequence analyses were conducted on blue whale samples from the Southern Hemisphere, the eastern tropical Pacific (ETP) and the northeast Pacific. The results indicate that the ETP is differentially used by blue whales from the northern and southern eastern Pacific, with the former showing stronger affinity to the region off Central America known as the Costa Rican Dome, and the latter favouring the waters of Peru and Ecuador. Although the pattern of genetic variation throughout the Southern Hemisphere is compatible with the recently proposed subspecies status of Chilean blue whales, some discrepancies remain between catch lengths and lengths from aerial photography, and not all blue whales in Chilean waters can be assumed to be of this type. Also, the range of the proposed Chilean subspecies, which extends to the Galapagos region of the ETP, at least seasonally, perhaps should include the Costa Rican Dome and the eastern North Pacific as well.


Segniagbeto G.H.,University of Lomé | Van Waerebeek K.,Agbo Zegue | Van Waerebeek K.,University of Ghana | Van Waerebeek K.,Peruvian Center for Cetacean Research | And 5 more authors.
Integrative Zoology | Year: 2014

Based on strandings and captures, 9 cetacean species, including 6 odontocetes and 3 mysticetes, are documented (photos and specimens) in Togo's coastal waters (newly-recorded species marked with an asterisk): Antarctic minke whale (Balaenoptera bonaerensis*), Bryde's whale (Balaenoptera brydei or B. edeni), humpback whale (Megaptera novaeangliae), sperm whale (Physeter macrocephalus), pygmy sperm whale (Kogia breviceps*), short-finned pilot whale (Globicephala macrorhynchus*), pantropical spotted dolphin (Stenella attenuata*), common bottlenose dolphin (Tursiops truncatus) and common dolphin Delphinus sp. An anecdotal sighting record for killer whale (Orcinus orca) is considered reliable. The lack of Sousa teuszii records in Togo is consistent with its apparent contemporaneous absence in Ghana. The B. bonaerensis specimen, entangled in a purse seine set on small pelagics, is a first record for the Gulf of Guinea. The occurrence of this Southern Ocean species north of the equator underscores the severe gaps in our understanding of cetacean distribution off western Africa. The majority of artisanal fishermen operating in Togolese coastal waters are of Ghanaian origin and are thought to promote trade and consumption of cetacean bushmeat. Because captures are illegal, enforced with some success in the main fishing centers, covert landings of cetaceans are exceedingly difficult to monitor, quantify or sample. Concern is expressed about pollution of Togo's coastal waters with heavy metals due to phosphorite mining and export from the coastal basin near Hahotoé and Kpogamé. © 2012 Wiley Publishing Asia Pty Ltd.


Mondolfi A.E.P.,A-Life Medical | Mondolfi A.E.P.,Institute Biomedicina | Talhari C.,University of the State of Amazonas | Sander Hoffmann L.,Federal University of Rio Grande do Sul | And 5 more authors.
Mycoses | Year: 2012

Lobomycosis, a disease caused by the uncultivable dimorphic onygenale fungi Lacazia loboi, remains to date as an enigmatic illness, both due to the impossibility of its aetiological agent to be cultured and grown in vitro, as well as because of its unresponsiveness to specific antifungal treatments. It was first described in the 1930s by Brazilian dermatologist Jorge Lobo and is known to cause cutaneous and subcutaneous localised and widespread infections in humans and dolphins. Soil and vegetation are believed to be the chief habitat of the fungus, however, increasing reports in marine mammals has shifted the attention to the aquatic environment. Infection in humans has also been associated with proximity to water, raising the hypothesis that L. loboi may be a hydrophilic microorganism that penetrates the skin by trauma. Although its occurrence was once thought to be restricted to New World tropical countries, its recent description in African patients has wrecked this belief. Antifungals noted to be effective in the empirical management of other cutaneous/subcutaneous mycoses have proven unsuccessful and unfortunately, no satisfactory therapeutic approach for this cutaneous infection currently exists. © 2012 Blackwell Verlag GmbH.


Jung J.-L.,University of Western Brittany | Mullie W.C.,Programme Biodiversite | Van Waerebeek K.,Peruvian Center for Cetacean Research | Van Waerebeek K.,Cheikh Anta Diop University | And 6 more authors.
Marine Biology Research | Year: 2016

The surveillance of marine mammal strandings within the framework of a biomonitoring scheme for the Mauritanian coast led to the discovery in 2013 of a 3.98 m long, juvenile rorqual Balaenoptera sp. in an advanced state of decomposition near Chott Boul (16°32.488′N, 016°27.0317′W). Photographs and skin samples were taken, but the specimen could not be collected. Based on limited morphological evidence, only Balaenoptera edeni and B. omurai were plausible. Sequences of three mtDNA regions, i.e. parts of the cox1 and the cytb genes as well as the D-loop, for a total of 2636 bp (> 16% of the mitogenome) identified the specimen as an Omura’s whale, B. omurai, the first record in the Atlantic Ocean and at least 11,400 km away from its closest known range in the SW Indian Ocean (Madagascar). The question of whether the specimen is a vagrant or belongs to an unrecognized Atlantic population is discussed. Advection by currents or transport on a ship’s bow bulb following collision are discarded. Circumstances (juvenile status, great distance from Indo-Pacific, necessary inter-oceanic passage through cold temperate waters) may slightly favour the hypothesis that B. omurai, if rare, could be autochthonous in the Atlantic. Beach surveys remain a useful tool to assess trends in cetacean species composition, to detect unusual mortality events and to help assess the impacts of anthropogenic activities. This is particularly applicable to remote areas where the marine mammal fauna is poorly known and where fisheries effort is high, such as the Mauritanian coast. © 2015 Taylor & Francis.


Tzika A.C.,University of Geneva | Tzika A.C.,Roosevelt University | D'Amico E.,Free University of Colombia | Alfaro-Shigueto J.,Pro Delphinus | And 5 more authors.
Conservation Genetics | Year: 2010

In the last 60 years, incidental entanglement in fishing gears (so called by-catch) became the main cause of mortality worldwide for small cetaceans and is pushing several populations and species to the verge of extinction. Thus, monitoring and quantifying by-catches is an important step towards proper and sustainable management of cetacean populations. Continuous studies indicated that by-catches and directed takes of small cetaceans in Peru greatly increased since 1985. Legal measures banning cetacean takes, enforced in 1994 and 1996, ironically made monitoring highly problematic as fishers continue catching these animals but utilize or dispose of carcasses clandestinely. Hence, in locations where cetaceans are landed covertly or already butchered, molecular genetic methods can provide the only means of identification of the species, sex, and sometimes the population of each sample. Here, we generate and analyse a fragment of the mitochondrial DNA cytochrome b gene and 5 nuclear microsatellite markers from 182 meat and skin samples of unidentified small cetaceans collected at three Peruvian markets between July 2006 and April 2007. Our results, compared to past surveys, indicate that Lagenorhynchus obscurus, Phocoena spinipinnis, Tursiops truncatus, Delphinus capensis, and D. delphis continue to be caught and marketed, but that the relative incidence of P. spinipinnis is highly reduced, possibly because of population depletion. The small number of possible sampling duplicates demonstrates that a high monitoring frequency is required for a thorough evaluation of incidental catches in the area. A wide public debate on by-catch mitigation measures is greatly warranted in Peru. © 2010 Springer Science+Business Media B.V.


Wang Y.,Shandong University | Li W.,Shandong University | Li W.,Chinese University of Hong Kong | Van Waerebeek K.,Peruvian Center for Cetacean Research
Marine Policy | Year: 2015

In the present study, the species composition, geographical and seasonal patterns of strandings, bycatches and injuries of aquatic mammals reported in Chinese mainland waters, from 2000 to 2006, were analyzed based on national official documents. A total of 97 strandings, 66 bycatches and 30 injuries, involving at least 18 species (possibly 20) in eight families of Cetacea and two families of Carnivora, were recorded. Finless porpoises (Neophocaena spp.), spotted seal (Phoca largha) and bottlenose dolphins (Tursiops spp.) were the most common species in all three categories, in total comprising 59.8% of strandings, 97.0% of bycatches and 86.7% of injuries. Strandings occurred throughout the year, but records of both bycatches and injuries peaked in spring (March to May), corresponding to the major fishing season and may reflect the negative impacts of fishing activities. The highest species diversity found in Fujian Province may be linked to upwelling and high production in the Strait of Taiwan. Serious difficulties were encountered in overall data interpretation and between-provinces comparability, mainly due to a lack of quantified observer effort and variable expertise levels. Hence the establishment of a coordinated nationwide network is recommended, providing a mechanism for the instant reporting of aquatic mammal events, as well as the adoption of a standardised data recording system including necropsy protocols. Better-quality data should allow quantitative analyses leading to an improved understanding of anthropogenic threats in China[U+05F3]s aquatic mammal populations. The need to upgrade reserve management, such as the Dalian protected area in Liaoning, is also stressed. © 2014 Elsevier Ltd.


Kiani M.S.,University of Karachi | Van Waerebeek K.,Peruvian Center for Cetacean Research
Advances in Marine Biology | Year: 2015

Limited historical and new information on Indian Ocean humpback dolphins, Sousa plumbea, in Pakistan are reviewed. Although present along most of the coast, S. plumbea concentrates in the mangrove-lined creek system of the Indus Delta (Sindh), Miani Hor (Sonmiani Bay), Kalmat Lagoon, Gwadar and the Dasht River estuary (Gwater Bay, Jiwani). Other areas of distribution comprise the Karachi coast, Kund Malir, Ormara and Pasni. In the Indus Delta, 46 small-boat surveys conducted monthly (minus July and October) in 2005-2009, documented 112 sightings (439 individuals) in major creeks, smaller channels and nearshore waters. Group sizes ranged from 1-35 animals (mean=3.92±4.60). Groups of 1-10 animals composed 91% of total (27.9% single animals). An encounter rate of 0.07-0.17 dolphins km-1 lacked a significant trend across survey years. A discovery curve remained steep after 87 dolphins were photo-identified, suggesting the population is vastly larger. In Sonmiani Bay, Balochistan, during 9 survey days in 2011-2012, group sizes ranged from 1-68 animals (mean=11.9±13.59; n =36), totalling 428 dolphins. Incidental entanglements, primarily in gillnets, pollution (especially around Karachi), overfishing and the ship breaking industry in Gaddani, pose major threats. Incidental catches occur along the entire Pakistani coast. Of 106 stranded cetaceans, 24.5% were S. plumbea. Directed takes in Balochistan, driven by demand for bait in shark fisheries, have reportedly declined following dwindling shark stocks. Habitat degradation threats include depletion of prey and increased maritime traffic. Domestic sewage and solid waste pollution are predominant on the Balochistan coast, especially at Miani Hor, Kund Malir, Ormara, Kalmat Lagoon, Pasni, Gwadar and Jiwani. An exhaustive habitat assessment combined with appropriate fishery management is the only way to safeguard the future of S. plumbea in Pakistan. © 2015 Elsevier Ltd.


PubMed | University of Karachi and Peruvian Center for Cetacean Research
Type: | Journal: Advances in marine biology | Year: 2015

Limited historical and new information on Indian Ocean humpback dolphins, Sousa plumbea, in Pakistan are reviewed. Although present along most of the coast, S. plumbea concentrates in the mangrove-lined creek system of the Indus Delta (Sindh), Miani Hor (Sonmiani Bay), Kalmat Lagoon, Gwadar and the Dasht River estuary (Gwater Bay, Jiwani). Other areas of distribution comprise the Karachi coast, Kund Malir, Ormara and Pasni. In the Indus Delta, 46 small-boat surveys conducted monthly (minus July and October) in 2005-2009, documented 112 sightings (439 individuals) in major creeks, smaller channels and nearshore waters. Group sizes ranged from 1-35 animals (mean=3.924.60). Groups of 1-10 animals composed 91% of total (27.9% single animals). An encounter rate of 0.07-0.17 dolphins km(-1) lacked a significant trend across survey years. A discovery curve remained steep after 87 dolphins were photo-identified, suggesting the population is vastly larger. In Sonmiani Bay, Balochistan, during 9 survey days in 2011-2012, group sizes ranged from 1-68 animals (mean=11.913.59; n=36), totalling 428 dolphins. Incidental entanglements, primarily in gillnets, pollution (especially around Karachi), overfishing and the ship breaking industry in Gaddani, pose major threats. Incidental catches occur along the entire Pakistani coast. Of 106 stranded cetaceans, 24.5% were S. plumbea. Directed takes in Balochistan, driven by demand for bait in shark fisheries, have reportedly declined following dwindling shark stocks. Habitat degradation threats include depletion of prey and increased maritime traffic. Domestic sewage and solid waste pollution are predominant on the Balochistan coast, especially at Miani Hor, Kund Malir, Ormara, Kalmat Lagoon, Pasni, Gwadar and Jiwani. An exhaustive habitat assessment combined with appropriate fishery management is the only way to safeguard the future of S. plumbea in Pakistan.


Mangel J.C.,Pro Delphinus | Mangel J.C.,University of Exeter | Alfaro-Shigueto J.,Pro Delphinus | Alfaro-Shigueto J.,University of Exeter | And 5 more authors.
Biological Conservation | Year: 2010

We detail the first direct, at sea monitoring of small cetacean interactions with Peruvian artisanal drift gillnet and longline fisheries. A total of 253 small cetaceans were captured during 66 monitored fishing trips (Gillnet: 46 trips; Longline: 20 trips) from the port of Salaverry, northern Peru (8o14′S, 78o59′W) from March 2005 to July 2007. The most commonly captured species were common dolphins (Delphinus spp.) (47%), dusky dolphins (Lagenorhynchus obscurus) (29%), common bottlenose dolphins (Tursiops truncatus) (13%) and Burmeister's porpoises (Phocoena spinipinnis) (6%). An estimated 95% of common dolphin bycatch was of long-beaked common dolphins (Delphinus capensis). Overall bycatch per unit effort for gillnet vessels (mean ± sd) was estimated to be 0.65 ± 0.41 animals.set-1 (range 0.05-1.50) and overall catch (bycatch and harpoon) was 4.96 ± 3.33 animals.trip-1 (range 0.33-13.33). Based upon total fishing effort for Salaverry we estimated the total annual average small cetacean bycatch by gillnet vessels as 2412 animals.year-1 (95% CI 1092-4303) for 2002-2007. This work indicates that, in at least one Peruvian port, bycatch and harpooning of small cetaceans persist at high levels and on a regular basis, particularly in driftnet vessels, despite the existence since the mid-1990s of national legislation banning the capture of marine mammals and commerce in their products. It is concluded that the coast of Peru is likely still one of the world's principal areas for concern regarding high small cetacean bycatch and there is clearly an urgent need to increase the geographic scope of observer effort to elucidate the full magnitude of this issue. © 2009 Elsevier Ltd. All rights reserved.

Loading Peruvian Center for Cetacean Research collaborators
Loading Peruvian Center for Cetacean Research collaborators