Johannesburg - A study has found that penguins' existence is affected by habitat loss, pollution and fishing and more Marine Protected Areas need to be established, the environmental affairs department said on Thursday."A major study of different penguin species has found that birds are at continuing risk from habitat degradation", the department said in a statement."[The study] recommends the establishment of more Marine Protected Areas (MPAs) to help mitigate against a range of effects, including food scarcity [where fisheries compete for the same resources], being caught in fishing nets, oil pollution and climate change."The statement was sent on behalf of the department and in collaboration with British Antarctic Survey Press Office.The study was conducted by a group of 49 internationally renowned scientists on 18 penguin species.According to the statement, populations of many penguin species have "declined substantially" over the past two decades."In 2013, 11 species were listed as 'threatened' by the International Union for Conservation of Nature, two as 'near threatened' and five as 'of least concern'", it said."In order to understand how they might respond to further human impacts on the world's oceans, the scientists examined all 18 species by looking at different factors where human activity might interfere with their populations."Endangered The study considered all the main factors affecting penguin populations.These included terrestrial habitat degradation; marine pollution; fisheries, by catch and resource competition; environmental variability; climate change and toxic algal poisoning and disease.The scientists found that the future resilience of penguin populations to climate change impacts would depend on addressing current "threats" to their existing habitat degradation on land and sea, said the department."The study further notes that protection of penguin habitats is crucial for their future survival", it said."This could be in the form of appropriately scaled marine reserves, including some in the High Seas, in areas beyond national jurisdiction."Head of Conservation Biology at the British Antarctic and the lead author of the study, Phil Trathan, said that penguins and humans often compete for the same food, and some of our other actions also impinge upon penguins.Trathan said the research highlighted issues of conservation and protecting biodiversity and the functioning of marine ecosystems."Whilst it is possible to design and implement large-scale marine conservation reserves, it is not always practical or politically feasible", he said in the statement."However, there are other ecosystem-based management methods that can help maintain biodiversity and a healthy ecosystem."The African penguin is only bred in South Africa and Namibia and is currently classified as globally endangered.The South African population of the African penguin has decreased by 65% since 2001.The bulk of the South African population is now found in Algoa Bay.Four species of penguin, king, Gentoo, macaroni and southern rockhopper breed in South Africa.They have all been classified as vulnerable or Endangered in a recent regional assessment conducted by BirdLife South Africa.