Potential impacts of five large dams on the Endangered Gangetic dolphins in the Brahmaputra River Basin, India

12 October 2010

Minister – Shri. Jairam Ramesh
Ministry of Environment and Forest, Government of India
Paryavaran Bhavan, CGO Complex, Lodhi Road
New Delhi – 110 003, India

Subject: Potential impacts of five large dams on the Endangered Gangetic dolphins in the Brahmaputra River Basin, India

Dear Minister,

The Board of the Society for Marine Mammalogy wishes to convey its concern about the future of the Gangetic dolphin (Platanista gangetica gangetica) in the Brahmaputra River system of India.

The Society for Marine Mammalogy consists of approximately 1,000 scientists from 60 countries and is dedicated to the study, understanding, and conservation of marine mammals and their ecosystems. Of the species of concern to our Society, river dolphins represent the most vulnerable to extinction because their entire distributions are in close proximity to humans. The first extinction of a dolphin known to have been caused by humans occurred just a few years ago and was of another river species in Asia: the baiji or Yangtze river dolphin.

We are very concerned about the future of Gangetic dolphins in the Brahmaputra River and its tributaries because of plans to construct multiple dams. We are particularly concerned about five of the almost 170 dams in the planning or construction stages that have the greatest potential to harm the Gangetic dolphins living downstream. These are the Lower Subansiri Dam (already under construction), the Lower Siang Dam, the Dibang Dam, Lower Damwe Dam, and Kulsi Dam. Individually, these dams are likely to result in declines in the range and abundance of Gangetic dolphins. Together, their cumulative impacts could lead to the complete disappearance of the species from the Brahmaputra River and its tributaries.

Only about 300 dolphins survive in the Brahmaputra system of India, as estimated from a recent survey by Dr Abdul Wakid, an internationally recognized expert on river dolphins in India. River dolphins depend on the relatively deep pools that form in particular portions of natural rivers, and this pool habitat will be degraded or even eliminated by the changes in river morphology and hydrology caused by the dams. The fluctuations in discharge associated with dam operation will also reduce fish diversity and abundance, further threatening dolphins.

We are also concerned that any reduction in fish diversity and abundance may have the potential to adversely impact the livelihoods of the local fishing people, which in turn may have consequential adverse effects on the dolphins through increased fishing effort.

We strongly believe that science should form the basis for management of natural resources and the conservation of biodiversity and that the future survival of the Gangetic dolphin would be significantly enhanced if the following actions could be taken:

  1. Conduct a comprehensive environmental impact assessment that explicitly includes the downstream impacts of the five dams, individually and cumulatively, on Gangetic dolphins and their prey.
  2. Conduct a comprehensive socio-economic impact assessment on the downstream impacts of the five dams, individually and cumulatively, on the local communities, especially the fishers.
  3. Develop a Brahmaputra Basin water development plan that ensures efforts to conserve Gangetic dolphins in one area are not undermined by dam construction in another area.
  4. Consider canceling plans for constructing one or more of the dams if the anticipated risks to the continued survival of the Gangetic dolphin are judged to be severe and cannot be reduced to acceptable levels.

The membership of our Society includes unparalleled expertise in river dolphin biology and risk assessment. We recognize the competing interests for precious water resources and offer our help and expertise in finding solutions that would allow humans and Gangetic dolphins to co-exist. We congratulate the Government of India for its recent declaration of the Gangetic dolphin (Platanista gangetica gangetica) as the National Aquatic Animal of India and hope that many generations of your citizens can enjoy and benefit from rivers with healthy dolphin populations.



Randall Wells, Ph.D.

Vaquita in the Upper Gulf of California

Dr. Adrián Fernández
Presidente, Instituto Nacional de Ecología
Av. Anillo Periférico 5000
Col. Insurgentes Cuicuilco
Delegación Coyoacán
México, DF 04530

April 22, 2010

Dear Dr. Fernández:

The Board of the Society for Marine Mammalogy (SMM) has been following with great interest recovery efforts undertaken by your Government to conserve the highly endangered vaquita (Phocoena sinus) in the Upper Gulf ofCalifornia. As you know, elimination of by-catch is the only approach that will ensure the survival of this endemic species. Since 2007, the Government of Mexico has invested an unprecedented level of funding to eliminate bycatch. The conservation actions taken to date, including buyouts,enforcement of areas closed to fishing, and development of alternative fishing gear, hold great promise to reverse the population decline of this species.

Critical to any conservation program is a monitoring scheme that will allow evaluation of the success of management actions taken over time. We believethat the time has come to implement an effective monitoring program to allow assessment of the efficacy of the critical measures taken to date. Recently the Instituto Nacional de Ecología (INE) convened a workshop to guide the design of such a monitoring scheme. The Report of the Workshopdetails a monitoring plan within the vaquita refuge, including a budget, timeframe and other actions. The Report has been reviewed favorably by several distinguished members of the SMM and by other scientists.

The Board of the SMM considers the scheme outlined in the WorkshopReport to be an effective means of monitoring the vaquita population. Due to the very small size of this population, it is clear that monitoring methods must achieve an unprecedented level of sampling precision. Achieving this level of precision will require a significant investment of funds, but we note that the cost will be small in comparison to the investment already committed to theconservation program and insignificant in relation to the potential ecological and societal costs of losing this iconic species. The Board of the SMM therefore, fully supports the workshop recommendations; we believe that these measures are a feasible means of monitoring this very small population of vaquitas.

Once again, the Board of the SMM offers to your Government its expertise in working towards the conservation of Mexico’s only endemic marine mammal species. Areas in which the Society could potentially assist your Government include:

  • Brokering partnerships with NGOs to assist with the cost of the monitoring
  • Assisting with the development of gear refinements with the aim of reducing bycatch in the areas open to fishing.

The Society looks forward to assisting the Mexican government in its internationally significant endeavors to save the vaquita.


Signature - Andrew J. Read

Andrew J. Read
Society of Marine Mammalogy


Dr. Eduardo Peters R
Director General de Ordenamiento Ecológico y Conservación de los Ecosistemas
Instituto Nacional de Ecología (INE)

Dr. Lorenzo Rojas-Bracho
Instituto Nacional de Ecología (INE)

Lic. Jorge López Vergara
Cargo: Oficial Mayor del Ramo

Western Gray Whales

Mr. Alexey B. Miller
Deputy Chairman of the Board of Directors
16 Nametkina St.
117997, Moscow, V-420. GSP-7

Mr. Sergey Bogdanchikov
President of Rosneft
Chairman of Rosneft’s Management Board
26/1, Sofiyskaya Embankment
1, GSP-8 117997
Moscow, Russia

CEO Rex W. Tillerson
ExxonMobil Corporation
5959 Las Colinas Boulevard
Irving, Texas 75039-2298

CEO Peter Mather
British Petroleum
International Headquarters
1 St James’s Square
London, SW1Y 4PD UK

Exxon Neftegas Limited
28 Sakhalinskaya Street
Yuzhno-Sakhalinsk, Russia 693000

Mr. Mikhailov Y.N.
Acting Director General
CJSC Elvary Neftegaz
78, Chekhova Street
693008 Yuzhno-Sakhalinsk
Russian Federation

April 22, 2010

The Board of Governors of the Society for Marine Mammalogy urges all parties involved in hydrocarbon exploration and production on the Sakhalin shelf to participate in the conservation of western gray whales (Eschrichtius robustus).

Western gray whales have been listed as critically endangered by the International Union for Conservation of Nature (IUCN,; the single remnant population contains approximately 130 individuals. The northeastern shelf of Sakhalin Island, Russia is the critical feeding ground for this population and western gray whales depend on this area for much of their food.

Hydrocarbon exploration and production activities in this area could have severe adverse impacts on this population by disrupting feeding in preferred areas, leading possibly to detrimental effects on individual whales and the gray whale population as a whole. Researchers reported the displacement of whales during a seismic survey in 2001 and behavioral observations made during that period indicated that some whales spent less time feeding and more time traveling when exposed to seismic noise. Deciphering the impact of such changes will require detailed studies of prey distribution, foraging ecology, and continued population monitoring.

In 2004, the International Union for the Conservation of Nature (IUCN) and the Sakhalin Energy Investment Company (SEIC) formed an Independent Scientific Review Panel, whose mandate was to evaluate the risks to gray whales from SEIC’s activities on the Sakhalin shelf. An important result of this review was a recommendation to relocate a major pipeline going from offshore platforms to Sakhalin Island. The originally planned route of the pipeline passed through some areas used most intensively by feeding gray whales. SEIC accepted the Panel’s judgment and chose a longer, but safer (from the point of view of the whales) route for the pipeline. The pipeline is now in operation and, although the relocation incurred some additional cost, it provided a tangible benefit to the whales. The success of this process led to the formation of the Western Gray Whale Advisory Panel, another partnership between IUCN and SEIC.

Oil and gas exploration and production activities will continue on the Sakhalin shelf for decades. Seismic air gun surveys will continue, as the industry needs to track the resources in the fields to maintain production. The planning of these seismic surveys by SEIC is another example of how the process administered by the Western Gray Whale Advisory Panel can minimize the impacts of industrial activity on gray whales. For example, an upcoming SEIC seismic survey has been scheduled to occur when the fewest whales are present on the feeding grounds, and the company has consulted extensively with the Western Gray Whale Advisory Panel to develop a detailed, robust monitoring and mitigation program.

The Western Gray Whale Advisory Panel process, in collaboration with SEIC, has clearly had some notable success. However, SEIC is only one of several oil companies operating on the Sakhalin shelf. To fully minimize impacts of hydrocarbon exploration and production on western gray whales, it is essential that all companies operating in the region participate in the process.

Therefore, the Board of Governors of the Society for Marine Mammalogy urges all parties involved in hydrocarbon exploration and production on the Sakhalin shelf and around the Sea of Okhotsk to participate in the WGWAP process and:

  • inform the Western Gray Whale Advisory Panel of all exploration and production activities planned and occurring off Sakhalin;
  • work co-operatively with the Western Gray Whale Advisory Panel to minimize adverse impacts of these activities on this critically endangered population of whales.
  • adopt and follow the recommendations of the Western Gray Whale Advisory Panel.

Thank you for considering our suggestions about this important conservation matter.


Signature - Andrew J. Read
Andrew J. Read, Ph.D.
President, Society for Marine Mammalogy