Following manatees across changing coastlines

A special focus on Lesser-Known Marine Mammals

Manatees are not often the first marine mammal people think of, and are often seen as a Florida only based mammal. However there are more populations out there than expected. Many know of dugongs; an Asia based herbivorous “sea cow” very similar to manatees, but did you know there are manatees in South America? And they are at the centre of an urgent conservation story.

Manatees are often misunderstood as simple or passive animals. In reality, they are highly perceptive and adaptable, with a remarkable ability to navigate complex environments and locate freshwater sources across large and changing landscapes. Their slow movements are often mistaken for a lack of awareness, when in fact they reflect a species finely tuned to its environment.

American manatees in this region, particularly in Brazil, have experienced an unusually high incidence of strandings, especially for neonates; the highest reported anywhere in the world.

Broad environmental degradation or human pressures in coastal habitats manatees depend on are why calves continue to strand year after year, though many strandings are preventable.Addressing root causes is what allows rehabilitation to remain a bridge to recovery, rather than a permanent emergency response.

This is the focus of long-term work led by manatee researchers and conservation partners, including by the UBC Institute of Ocean and Fisheries’ Marine Mammal Research Unit’s Research Associate Dr. Carol Meirelles. Dr. Meirelles’ research in this area focuses on fieldwork, rescue and rehabilitation, and regional collaboration to better protect manatees. Understanding how they use the environment and what types of actions can reduce risk before emergencies happen.

This is the focus of long-term work led by manatee researchers and conservation partners, including by the UBC Institute of Ocean and Fisheries’ Marine Mammal Research Unit’s Research Associate Dr. Carol Meirelles. Dr. Meirelles’ research in this area focuses on fieldwork, rescue and rehabilitation, and regional collaboration to better protect manatees. Understanding how they use the environment and what types of actions can reduce risk before emergencies happen.

Take rehabilitation, for example. Responding to strandings can prevent immediate population losses, but it is resource-intensive, especially for calves.

“Young manatees require years of continuous care, specialized facilities, and highly trained teams to survive and eventually return to the wild,” said Dr. Meirelles. “Rehabilitation plays a critical role, but it is not a long-term solution on its own. If the underlying causes of strandings, such as habitat loss, reduced access to freshwater, and human disturbance, are not addressed, rehabilitation risks becoming a permanent emergency response rather than a pathway to recovery

Conservationists need a clear picture of where manatees are, how they move, and what conditions make habitats viable. “We have been using spatial ecology: looking at how animals use space over time and how that relates to environmental conditions and human activities, to understand the situation,” Dr Meirelles says. “Manatees in tropical waters live in a variety of habitats, requiring safe feeding areas, reliable freshwater sources, and shallow, calm water refuges, that they can move between during the year. Mapping their patterns assists with conservation planning, impact assessment, and management decisions.”

Multiple data sources are used, including citizen science sightings and telemetry data. Stranding records also provide information about risk exposures and mortality patterns. Traditional and local ecological knowledge can also help fill gaps in regions that are poorly represented by systematic surveys. Each data source must be interpreted carefully. As a result, stranding locations do not necessarily reflect where manatees are living, but can reflect where lost calves or carcasses are most likely to be recovered. The goal is not to discard any data type, but to understand what each one represents and explicitly account for bias in spatial analyses.

Human activities and climate change are already reshaping this habitat network. In semi-arid regions of Brazil, manatees have largely stopped using estuaries that have become hypersaline due to climate change and human impact and now rely almost entirely on submarine freshwater springs. These are limited and vulnerable freshwater sources. It also reinforces the need for mapping movements and habitat connections. Protecting feeding areas alone is not enough if freshwater access is shrinking, or if the corridors that connect key habitats become disrupted.

To gather more information, Dr. Meirelles gathered specialists from across South America to form the Alliance for Manatees. Using evidence-based data, such as models, maps, and priority areas, the Alliance provides decision-makers with information that can move reactive conservation to more proactive approaches. This can identify priority areas before conflicts arise, guide coastal and marine spatial planning, and improve environmental impact assessments by grounding them in evidence of actual habitat use rather than assumptions or incomplete data. In places where information has been scarce, fragmented, or unevenly distributed, reducing uncertainty, and increasing transparency can determine whether conservation is built into planning early, or only considered after losses become obvious.

Public understanding is part of this picture too. “For the Brazilian American manatee subpopulation, regional coordination and better integration of science into decision-making and planning, will mean greater stability, fewer calf strandings, improved protection of key habitats, and more secure access to freshwater in a changing climate,” said Dr. Meirelles.

“Moving our understanding of these unique regionally based marine mammals into the mainstream will help us all recognize the ecological complexity and social realities of conservation objectives, and keep manatees thriving in the wild.”

Tags: Brazil, Carol Meirelles, conservation, freshwater, habitats, manatees, Marine Mammal Research Unit, marine mammals, MMRU, strandings