This year, manatee appreciation day has fallen on 31st March and a great way to celebrate this is to spread awareness of these gentle marine mammals.
Species of Manatee
There are three species of Manatee across the globe which are distinguished by their geographical location. They are often referred to as ‘sea cows’ due to their large physique and slow, placid nature however, they are actually related to elephants. Manatees are primarily herbivores, feeding on a diet of over 60 different freshwater and saltwater plants and can weigh up to 1,300 pounds! Impressively, they are able to consume a tenth of their own weight in just 24 hours!
Their average life span in the wild is 40 years and their size can vary from 8 to 13 feet long. These gentle mammals are born underwater (their babies are called calves) where the mother helps them to the surface for their first breath. However, manatees are perfectly adapted and within an hour of being born, the calves can swim on their own.
West Indian Manatee: Located along the North American east coast from Florida to Brazil.
Amazonian Manatee: Are found in the Amazon River.
African Manatee: Occupy the west coast and rivers of Africa.
Threats to Manatees
Manatees, which once were classified as ‘endangered’, had their category downgraded to ‘threatened’ in 2017. Although this is a step in the right direction, the species still has many threats today.
Red tides / Harmful algal blooms: This is an event where the naturally present Karenia brevis microorganism grows rapidly in large numbers. This occurrence produces brevetoxins which can have toxic effects on the central nervous system of animals. The manatees will consume seagrass which contains the toxins and also breathe in the airborne toxins as they surface. This can lead to seizures and even drowning. In 2018, Florida Fish and Wildlife (FWC) found that 26% of the recovered deceased manatees they found had died due to red tide exposure.
Boat Strikes: Unfortunately the areas which manatees inhabit (rivers, estuaries and coastal waters) are also areas heavy with boat traffic. Due to the manatees often feeding in shallow waters and being close to the surface, they are put at high risk for boat collisions. Boat collisions are the leading cause of human-related deaths for manatees. It has been found in a 2004 study that a staggering 97% of manatees have scars from boat strikes. The best way to try and stop this is for boats to always avoid areas with manatees if possible. Follow the signs posted advising of their presence. Also never feed manatees. This will train them to associate boats with a food source, encouraging them to swim into boat’s paths.
Marine debris / pollution: Like many other marine animals, manatees are also negatively impacted by marine debris. They can become entangled in fishing gear or consume plastic which is floating in the water. A study conducted in 2017 showed that over a 20 year time frame, a shocking 11% of deceased manatees studied had ingested rubbish or showed signs of entanglement. Manatees are also at risk from climate change and habitat loss so if we can clean up our oceans and properly dispose of our waste then at least we can improve the habitat they do have.
Fun Facts about Manatees
They inspired mermaid legends. Many voyagers would see the figure of manatees in the water and believe they may have witnessed the legendary mermaid. Christopher Columbus caught a glimpse of three mermaids (which were really manatees) and wrote “they are not so beautiful as they are said to be, for their faces had some masculine traits.”
A diverse family tree. All species of manatee belong to the sirenius family. This means they share a common ancestor with the elephant, aardvark and small gopher-like hyrax!
Manatees cannot turn their heads. Manatees do not have the neck vertebra that most other mammals possess. Therefore they have to turn their entire bodies to look around.
Manatees never leave the water. Instead, they simply come up for air every 5 minutes or so. However, when resting, they can hold their breath for up to 20 minutes and when exerting greater energy they may surface every 30 seconds for air.
Manatees can swim at speeds up to 15 miles per hour. Manatees are usually slow moving animals and travel at around 5 miles per hour. This often means algae and barnacles grow on their backs! However, they can swim short bursts at 15 miles per hour if required.
For such a gentle creature, manatees truly are unique and should definitely be appreciated!