The Guyana dolphin (Sotalia guianensis) belongs to the smaller dolphin species and lives exclusively in South America along a narrow coastal strip from Honduras to Brazil. Because of its nearshore distribution, this species is heavily impacted by human activities. In Venezuela, the main distribution areas are the Orinoco River and Lake Maracaibo. The World Conservation Union IUCN Red List classifies the Sotalia dolphin as potentially endangered (NT). However, at the regional level, the species is classified as endangered. Due to the increase in fishing activity along the entire range and habitat destruction, it is feared that local populations are in danger of disappearing altogether in the future. Lack of monitoring and control has dramatically worsened the situation for these dolphin populations.
Several genetic and morphological studies indicate that the Guyana dolphin population from Lake Maracaibo must be considered a distinct management unit due to differences from the rest of the population. Lake Maracaibo has the highest bycatch rate for this species, with a casualty rate of 180 individuals/year. It is the only region in Venezuela where a dolphin species is exploited for human consumption. In addition, there are regular problems at the oil pipelines with disastrous consequences for the environment. There are approximately 15 oil spills per year in Lake Maracaibo, resulting in contamination with heavy metals and other toxins. Initial studies have already demonstrated negative impacts on marine mammals.
Although studies on population size, behavior, and biology are available at the global level for the Sotalia Guyana dolphin, such findings are unknown for the Maracaibo population. To better evaluate the extent of the bycatch problem, a monitoring program is important.
Successes and progress to date
Thanks to PROYECTO SOTALIA and YAQU PACHA, various studies on the biology and endangerment of the Guyana dolphin have been carried out in Lake Maracaibo (13,000 km²) since 2016.
For example, since 2016, data on the number of animals killed by fishing has been systematically recorded and consumption by the local population has also been documented. Based on these numbers, mortality rates can be better defined. In addition, tissue samples of dead animals are examined to determine possible contamination with mercury and heavy metals. These data are relevant to assess the health status of this dolphin population, but also to outline the risk to humans. Initial figures indicate that the levels of some harmful substances are particularly high, so that consumption of the meat by humans poses a health risk. In collaboration with other NGOs, a campaign has been launched to warn people against eating dolphin meat and thus protect Guyana's dolphins.
Equally important is the recovery of so-called ghost nets, which repeatedly cause animals to become entangled and subsequently die. This work is carried out in cooperation with various other NGOs, including the shark research center CIT Venezuela.
In the area of outreach and education, with the support of YAQU PACHA, a poster on the impact of heavy metals on the ecosystem of Lake Maracaibo was designed and distributed to fishermen and other people living there. Informative posters have also been completed and distributed in recent years. Visiting schools is another important part of the environmental education work.
On the occasion of the International River Dolphin Day, our partners Proyecto Sotalia had an information event in Venezuela.
Many interested people came to this event and our biologist Yurasi Briceño reported about the work on the protection of the dolphins and our activities in Venezuela.
Ethnobiology of the Guyana dolphin(Sotalia guianensis) and traditional knowledge of artisanal fishers in the state of Espírito Santo, southeastern Brazil.
The Guyana dolphin(Sotalia guianensis) is a dolphin threatened by accidental capture in set nets used in artisanal fisheries in the central coastal mesoregion of Espírito Santo (ES) in southeastern Brazil.
For the state of Brazil, there is little information about these dolphins. The Brazilian National Action Plan for the Protection of Endangered Cetaceans (PAN dos Cetáceos Marinhos) highlights the urgent need to collect data on traditional knowledge for the Espírito Santo coast. The objective of this study is to identify, with the knowledge of fishermen, the interactions between sotalia dolphin and artisanal fisheries in the areas where they occur, for the meso region of the central coast of Espírito Santo. In addition, environmental awareness actions will be carried out with children from public schools in fishing communities.
With the results obtained, it will be possible to understand the areas of use and human interactions with the species and achieve the goals of the PAN of Marine Cetaceans, the Decade of the Oceans and Sustainable Development Goal No. 14 "Life in the Water" of the 2030 Agenda. This part of the Sotalia Dolphin project is carried out in collaboration with our partners ECOLOGIA HUMANA DO OCEANO.
Team Latin America | Sea Otter Project | Chilean Dolphin Project | Chilean Dol phin | 30 Years of YAQU PACHA e.V. | Information on the Dolphin Species | Species Conservation | Project Manatis | Project Vaquita | Project Bottlenose Dolphin | Project La Plata Dol phin | Expedition to the Inias in the Rio Casiquiare