Enforcement paying off for the Atlantic humpback dolphin of Western Africa

Like many threatened species, the Vulnerable Atlantic humpback dolphin (Sousa teuszii) is under pressure from anthropogenic activities. Industrial and commercial scale fishing forces locally-based artisanal fishers to within 200 metres of the beach – using their nets in critical habitat for this poorly understood marine mammal. In a recent field report to SOS Save our Species, who funded the work, Tim Collins from the Wildlife Conservation Society (WCS) and IUCN CSG Member, reports on the impact of routine and frequent surveillance patrols in the waters of Conkouati-Douli National Park (CDNP), in the Republic of Congo – one of two project sites- to deter and intercept the trawlers that are deemed the root cause of the problem.

Humpback dolphins near the border of Gabon and Congo. They are known to routinely traverse this frontier. Photo Credit: Tim Collins

According to project director, Tim Collins, patrols have intercepted 15 trawlers (both metal hulled and wooden vessels) fishing illegally in park waters since December 2013. He explains that with a limited number of eco-guards on a single patrol boat, it is difficult to board every illegal vessel in the area, and typically some flee during intercepts. More recently, park waters have become empty of trawlers during the day, but vessels have started to come in after dark, usually around 8-9pm, leaving again by 5-6am, while Tim and colleagues evaluate how to adapt to this new pattern of activity. One option being discussed is to head out late in the day, heading into deeper water under cover of darkness, anchoring at sea. Trawlers fishing illegally would be intercepted at first light when they are heading back out to sea, explains Tim, although this is not without risk, he adds!

A juvenile humpback dolphin killed by a coastal, artisanal gillnet. Photo Credit: Tim Collins

Commenting on intercepted fishing boats, Tim explains these are generally registered locally with crews comprising a mix of Congolese and Chinese expatriates. In each case, skippers and vessels’ paperwork were taken into custody and brought to land for prosecution, and in most cases, the vessels themselves were escorted to the anchorage near coastal villages to facilitate processing of fines and confiscation of gear. In addition some larger West African pirogues fishing with long filets dormant – bottom set gill nets often over 2.5km long – with Congolese, Beninese, Ghanaian and Senegalese crews, have also been found in the park. All of these have been made to recover their nets and advised on where park limits lay. These boats are treated more leniently although are always provided with a warning.

Crucially, funds collected from the fines have been reinvested in strengthening enforcement in the national park with a part set aside for funding local fisheries cooperatives. This has been incredibly important for the project and fishers alike according to Tim. “We promised fishers that we would take action and in return they would honour an agreement to free the inshore strip – dolphin habitat. Being able to complete missions and return some of the financial benefits is critical and is helping to generate local support and buy-in”. This is extremely hard to do in a place where most people live from meal to meal and have very little room to make personal sacrifices, or risk loss such as moving their nets back into a risky area.

While part of the solution involves removing the trawler threat, the project’s sustainable impact comes from improving stakeholder management of local fisheries, in conjunction with the creation of local fishing cooperatives to improve management of artisanal fisheries. The positive results of the marine patrols, along with the efficient and clear reinvestment of fine funds into park management and the creation of local fishing cooperatives, attest not only to the success of the conservation initiative but also to the interest of both national authorities and local communities to enforce regulations and improve the conservation prospects of coastal dolphins and other species within CNDP. For more information about this project’s work in Mayumba National Park (Gabon) and Conkouati-Douli National Park (Republic of Congo) please visit the project page here.

News article is reproduced from SOS Save Our Species: the original article is at this link

Update on Mekong and Ayeyarwady Irrawaddy dolphin conservation

With support of the CSG, further steps were taken recently toward the conservation of two of Asia’s three riverine populations of Irrawaddy dolphins Orcaella brevirostris: in the Mekong of Cambodia and Laos and in the Ayeyarwady of Myanmar.

Mekong River Irrawaddy Dolphins

The critically endangered Mekong River population has been the subject of ongoing global interest and concern, and an ad hoc team of international conservation scientists has been providing advice to local conservationists in the Cambodian Fisheries Administration and WWF-Cambodia since 2009 (see reports from 2009 and this background summary). Since 2012 and the landmark Kratie Declaration on the Conservation of the Mekong River Irrawaddy Dolphins, major changes have occurred in the governance and management of dolphin conservation efforts within both the Cambodia government and WWF-Cambodia. In view of those changes, local partners decided to organize a workshop in Phnom Penh to assess progress on implementation of the recommendations from the Kratie Declaration and to update Cambodia’s river dolphin conservation strategy. Randall Reeves co-chaired the event which was well attended by local government and civil society representatives. CSG members Bob Brownell, Andy Read, Brian Smith, Randy Wells and Gerry Ryan as well as Frances Gulland of the SSC Wildlife Health SG, Helene Marsh of the SSC Sirenia SG and current president of the Society for Marine Mammalogy, and Peter Thomas of the US Marine Mammal Commission also participated in the workshop.

The workshop affirmed that significant progress had been made since the Kratie Declaration, notably in the reinforcement of patrolling activities by river guards and the refinement of protocols to investigate mortality. Nonetheless, the group concluded that entanglement in gillnets remains the most critical and immediate threat to the survival of dolphins in the Mekong and that concerted efforts are needed to address this issue even more vigorously. Also, other threats have emerged, most importantly the notification by Laos of its intention to proceed with construction of a hydropower dam at Don Sahong near the Cambodia border, starting later this year. Proposals for hydropower dams cover almost the entire current range of the Mekong dolphins. Construction of the Don Sahong dam as well as the Xayaburi dam farther upstream in a major tributary of the Mekong in Laos would set a poor precedent as the proliferation of dams in the Mekong would almost certainly spell the end for dolphins in this river system. (WWF is campaigning to prevent construction of the Don Sahong dam). The workshop made a series of recommendations related to strengthened research on demography and mortality of the dolphin population as well as more rigorous analyses of the booming dolphin-watching tourism industry. The full report of the workshop is available here.

Ayeyarwady River dolphins

Given the assembled expertise on river dolphin conservation, the conveners took advantage of the opportunity to hold a separate discussion on the deteriorating situation of the critically endangered dolphin population in the Ayeyarwady River (click here for report). Irrawaddy dolphins in both the Mekong and Ayeyarwady share similar conservation challenges. These include low population size, a declining range, suspected high mortality from gill-net entanglement, illegal electro-fishing, and plans for constructing hydroelectric dams in the mainstem and major tributaries. Compared to the Mekong, much less is known about demography and mortality of dolphins in the Ayeyarwady. As a consequence, a great deal of the discussion focused on identifying information gaps and appropriate strategies for filling those gaps. The long-standing co-operative fishing relationship between dolphins and cast-net fishermen in the Ayeyarwady appears to have broken down due to diminished catches and the disturbance caused by electro-fishing. This illegal fishing technique is practised extensively in the Ayeyarwady but is particularly difficult to stop because it is done surreptitiously by armed gangs at night.

In addition to highlighting the potential disappearance of the human-dolphin cooperative fishery and the ecological problems caused by electro-fishing, the group made recommendations and expressed concern about topics including the importance of conducting rigorous surveys; the apparent resurgence of gold-mining in the river mainstem; the need to understand  movement patterns with respect to population fragmentation; the value of establishing a  mortality monitoring network and a site-specific necropsy protocol that includes an examination for external signs of contact with fishing gear; and the importance of conducting a rigorous assessment of the potential impacts of planned dams. Finally, the group recognized that the participation of international experts has been extremely useful in helping to establish conservation measures and research initiatives in the Mekong River. They therefore suggested that a similar approach would be useful in Myanmar.

After the workshop, Helene Marsh travelled to Yangon to meet with Aung Myo Chit, a local conservationist in Myanmar who is in the process of establishing a foundation for the protection of Irrawaddy dolphins, and staff from the Wildlife Conservation Society Myanmar Program and the Myanmar Department of Fisheries. Together with these partners, Marsh developed a proposal to convene the First International Workshop on the Management and Research Priorities for the Ayeyarwady Dolphin, tentatively planned for late 2014 or early 2015.

There are four (maybe more) separate species of Sousa

By Peter Corkeron (20th April 2014)

Dolphins in the genus Sousa, the humpback dolphins, occur in coastal waters of West Africa, around the Indian Ocean, and in SE Asia and Australia. A recent scientific paper starts to clarify the number of species in the genus. Martin Mendez and Howard Rosenbaum from the Wildlife Conservation Society and American Museum of Natural History pulled together a large team of collaborators from across the taxon’s range. Together, they amassed 235 genetic and 180 morphological samples for new analyses. Previous genetic work, particularly that led by Cèline Frère, suggested that Sousa in Australian waters are distinct from those elsewhere. Earlier morphometric work by Tom Jefferson and Koen Van Waerebeek had not found differences among samples across the Indo-Pacific, suggesting caution when dividing the “Indo-Pacific” clade of Sousa into separate taxa. Mendez and coauthors’ new paper reanalyzed the morphometric data and detected differences, supporting the concept of at least four separate species: S. teuszii in West Africa, S. plumbea in the central and western Indian Ocean, S chinensis in the eastern Indian and western Pacific oceans, and an as yet unnamed Australian species.

A Western Indian Ocean Humpback dolphin (Sousa plumbea) surfaces near Fumba, west Zanzibar, Tanzania. Photo: Gill Braulik

 There’s further evidence suggesting two distinct groups (south-east Africa and the Arabian Peninsula) in the western portions of the range of S. plumbea, and the status of dolphins between south-east Asia and the Indian subcontinent probably won’t be resolved without more sampling. The “Australian” species (which lacks the dorsal “hump” characteristic of S. plumbea and S. teuszii) probably also occurs around the island of New Guinea although establishing the limits of its range will require further sampling in Indonesia, Malaysia and Papua New Guinea. Mendez’s previous work demonstrating links between oceanography and genetic distinctiveness in Sousa suggests ways forward.

 What does this mean for Sousa conservation? S. chinensis, S. plumbea and the Australian species tend to occur in small, relatively isolated populations. Sousa generally tend to live close to shore in areas that are either already heavily affected by human activities or that are becoming more so.  Their restricted coastal distribution, susceptibility to bycatch, and proximity to various human activities make them extremely vulnerable, and all Sousa populations are of conservation concern.

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