Aarin-Conrad Allen, Florida International University

The gentle, slow-moving Florida manatee has no natural predators.

And yet, these charismatic mammals face numerous threats.

Manatees are struck by vessels in busy waterways across the state, and a majority bear scars from these collisions.

Harmful algal blooms – characterized by the rapid growth of algae that degrades water quality – can impair their nervous systems.

With less blubber, or fat, compared with other marine mammals like whales, dolphins, seals and sea lions, manatees are vulnerable to cold-stress syndrome during winter months.

And they can ingest or get entangled in marine debris like derelict fishing gear and drown or be crushed by floodgate and water control structures.

I am a doctoral candidate in marine biology at Florida International University’s Institute of Environment. Over the past 15 years, I have gained extensive experience working with marine mammals, particularly manatees.

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Recently, my colleagues at the United States Geological Survey, Florida Department of Environmental Protection and I documented a change in the dietary pattern of manatees. We found that manatees are eating less seagrass – traditionally their primary food source – and more algae than in decades past. This change occurred along Florida’s Atlantic coast during a period of extensive seagrass decline.

We believe this represents an emerging threat to the species’ survival.

Protected species

Manatees were listed as an endangered species under the Endangered Species Act of 1973. By the early 1990s, the manatee population in Florida had dwindled to less than 1,300.

Researchers believe that federal protection, along with additional state measures such as slow-speed zones and no-entry refuges, has contributed to the growth of the manatee population in Florida.

In 2017, manatees were reclassified from endangered to threatened. Surveyors counted 5,733 individual manatees during a statewide aerial survey conducted in 2019.

Florida manatees average 9-12 feet (2.7-3.7 meters) in length and typically weigh about 1,000 pounds (450 kilograms), but they can grow as large as 3,500 pounds (1,600 kilograms). As the largest fully aquatic herbivore, they consume 5% to 10% of their body weight in vegetation each day.

While manatees eat a broad diet of over 60 different plants, they most commonly feed on species of seagrass. Seagrasses are marine plants that, like land plants, have leaves, flowers, roots and seeds, and make their food through photosynthesis.

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So what happens when these seagrasses are no longer available?

A changing estuary

The Indian River Lagoon is an estuary along Florida’s east coast that covers roughly 350 square miles (560 square kilometers) between the mainland and barrier islands, from Ponce Inlet to Jupiter Inlet.

It is a critical habitat for manatees, which feed on native seagrass meadows in the lagoon during their seasonal migrations.

Seagrasses are vital to the health of marine ecosystems. They are a habitat for juvenile fish and other marine organisms, provide food for aquatic herbivores, reduce carbon in the atmosphere and improve water quality. They also protect coastal habitats by stabilizing sediments and reducing wave energy that can erode shorelines and damage coastal infrastructure, especially during hurricanes.

For more than a decade, the Indian River Lagoon has experienced extensive loss of seagrass meadows, due to a series of algae blooms associated with nutrient runoff and degraded water quality from septic overflow leaching into the environment.

When untreated sewage and fertilizers flow into the estuary, they add nitrogen, phosphorus and other nutrients that drive excessive algal growth. These harmful algal blooms deplete oxygen levels and block sunlight, which seagrass needs for photosynthesis.

Between 2011 and 2019, over 50% of all seagrass in the lagoon was lost. This led to an increase in macroalgae and even led to a change in the animal communities that live in the lagoon. For example, among finfish, sheepshead populations declined, while seabream numbers increased. Invertebrate communities were also affected, with bryozoans colonizing areas previously dominated by barnacles.

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Manatees along the Atlantic coast have suffered two unusual mortality events since the seagrass decline, including one that is ongoing. Researchers attribute the increase in manatee deaths to malnutrition due to a shortage of seagrasses in the Indian River Lagoon.

A shift in manatees’ diet

In our study, we examined 193 manatee stomach samples collected from carcasses recovered from the Indian River Lagoon during two time periods – one before and one after the onset of the seagrass loss in 2011.

We compared stomach sample contents from carcasses collected between 1977 and 1989 with samples collected between 2013 and 2015.

Our findings indicate that manatees consumed 45% less seagrass and 74% more algae after the seagrass decline.

Recently, in a study supported by FIU’s Center for Aquatic Chemistry and Environment, I investigated differences in the nutritional composition – like protein, fat, carbohydrate and fiber – of items identified in manatee stomach samples. My preliminary results show notable differences in the nutritional composition of seagrass and algae.

Marine mammals are particularly vulnerable to dietary shifts due to their large size and high energy demands. Such changes can worsen their physical health and increase the likelihood of starvation.

Depleted oxygen levels are having a similar impact on aquatic vegetation and seagrass meadows in other regions of Florida, like Biscayne Bay and the Caloosahatchee River and Estuary. This suggests that the ecological challenges seen in the Indian River Lagoon could become more widespread.

What is the solution?

Remediation efforts within the lagoon have incorporated the restoration of seagrass through aquaculture and replanting strategies, similar to efforts to restore coral reefs.

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While the lagoon’s seagrass has recently shown signs of regrowth, the rehabilitation of the ecosystem must begin with improving and maintaining water quality.

Counties along the lagoon have enacted fertilizer bans that aim to reduce the levels of nitrogen and phosphorus in the water that drive algal blooms.

New research, however, indicates that these restrictions alone will not fix the problem, as residential septic systems are the primary source of nutrient pollution in the lagoon.

Furthermore, many of the factors contributing to harmful algal blooms are intensified by global warming and changing climate, which could accelerate the decline of seagrass in Florida and elsewhere.

Given the multiple, synergistic threats facing manatees, I believe that improving water quality, protecting their food sources, and further research – coupled with community outreach and education – are critical to ensure the long-term survival of this iconic Florida species.

Aarin-Conrad Allen, Ph.D. Candidate in Marine Sciences, Florida International University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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The science section of our news blog STM Daily News provides readers with captivating and up-to-date information on the latest scientific discoveries, breakthroughs, and innovations across various fields. We offer engaging and accessible content, ensuring that readers with different levels of scientific knowledge can stay informed. Whether it’s exploring advancements in medicine, astronomy, technology, or environmental sciences, our science section strives to shed light on the intriguing world of scientific exploration and its profound impact on our daily lives. From thought-provoking articles to informative interviews with experts in the field, STM Daily News Science offers a harmonious blend of factual reporting, analysis, and exploration, making it a go-to source for science enthusiasts and curious minds alike. https://stmdailynews.com/category/science/

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New Shepard 28

Blue Origin has once again captured the public’s imagination with the announcement of its ninth human flight, the NS-28 mission, set to launch from Launch Site One in West Texas on Friday, November 22. With the launch window opening at 9:30 AM CST (15:30 UTC), excitement is brewing as space enthusiasts and potential future astronauts gear up for another exhilarating journey into the cosmos.

One of the highlights of this mission is the crewed aspect, making it another significant step in Blue Origin’s mission to democratize access to space. Following the success of its previous flights, NS-28 promises to deliver an experience that will inspire and ignite passion for space exploration. The live webcast on BlueOrigin.com will commence at T-30 minutes, offering spectators a front-row seat to this groundbreaking event.

The NS-28 Mission Patch: A Story of Meaning and Symbolism

Accompanying the NS-28 mission is a beautifully designed mission patch that encapsulates the spirit and purpose of this historic flight. Each element of the patch carries deep significance, painting a portrait of the crew and their aspirations in space.

• Emily Calandrelli is represented by the color pink and a girl in signature pink overalls, acknowledging her influential role as a science communicator and advocate for space education.
• For Sharon and Marc Hagle, this flight marks their second journey on New Shepard, a milestone aptly symbolized by the centerline in the “2,” fostering a sense of continuity and commitment to space travel.
• The stars in the mission patch signify Austin Litteral’s enduring vision of humanity’s place among the stars, highlighting the adventurous spirit that drives our quest for knowledge beyond our planet.
• At the bottom of the patch, a representation of people embodies J.D. Russell’s hope for future generations to expand their understanding of the universe, underscoring the mission’s educational and inspirational goals.
• Lastly, the wolf in the crew capsule’s window stands as a tribute to Hank Wolfond, symbolizing the strength, courage, and tenacity that is required for exploration beyond our earthly confines.

Looking Ahead: The Future of Space Tourism and Exploration

As Blue Origin prepares for the NS-28 mission, more than just a flight is at stake. This mission represents a significant leap in commercial space travel and signifies a broader movement towards making space accessible and enjoyable for everyone. Each launch brings us closer to a future where experiencing space is a possibility for many, rather than just a select few.

With the countdown ticking down to November 22, stakeholders, space enthusiasts, and the general public alike are encouraged to tune in to the live webcast and partake in the excitement surrounding human spaceflight. Innovations in technology and a shared passion for exploration are paving the way for a new era of discovery—one where the stars are no longer out of reach.

Join us in celebrating the NS-28 mission—an emblem of human ingenuity, curiosity, and the indomitable spirit of exploration. See you on launch day—let’s reach for the stars together!

For more information about the crew, please see our previous blog post here

Or read the post from Blue Origin here.

Follow Blue Origin on X, Instagram, Facebook, LinkedIn, Threads, and YouTube, and sign up at BlueOrigin.com to stay updated on all mission details.

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The science section of our news blog STM Daily News provides readers with captivating and up-to-date information on the latest scientific discoveries, breakthroughs, and innovations across various fields. We offer engaging and accessible content, ensuring that readers with different levels of scientific knowledge can stay informed. Whether it’s exploring advancements in medicine, astronomy, technology, or environmental sciences, our science section strives to shed light on the intriguing world of scientific exploration and its profound impact on our daily lives. From thought-provoking articles to informative interviews with experts in the field, STM Daily News Science offers a harmonious blend of factual reporting, analysis, and exploration, making it a go-to source for science enthusiasts and curious minds alike. https://stmdailynews.com/category/science/

Excitement is building as NASA prepares for the upcoming launch of the Progress 90 spacecraft, a critical mission that will deliver essential supplies to the crew aboard the International Space Station (ISS). With a launch scheduled for 7:22 a.m. EST on Thursday, November 21, from the Baikonur Cosmodrome in Kazakhstan, this unpiloted Roscosmos cargo spacecraft will transport nearly three tons of food, fuel, and vital equipment to the Expedition 72 crew.

Tune In for Live Coverage

NASA is offering live launch coverage starting at 7:00 a.m. EST on the day of the launch, available on NASA+ and their official website. This is a fantastic opportunity for space enthusiasts and curious minds alike to witness firsthand the relentless efforts of international space collaboration. Not sure how to catch the excitement? NASA has made it easy! Their live coverage can be accessed through various platforms, including social media, so you won’t miss a moment of this thrilling event.

Mission Timeline

Following the launch, the Progress 90 spacecraft will embark on a two-day journey to the ISS, a remarkable feat of engineering and logistics. It is scheduled to autonomously dock at the space-facing port of the Poisk module on Saturday, November 23, at 9:35 a.m. EST. Make sure to tune in for NASA’s coverage of the docking process, which will begin at 8:45 a.m. that same day. Observing the intricate choreography of rendezvous and docking showcases the ingenuity of modern space missions.

Before Progress 90 arrives, it’s important to note that the previous Progress 88 spacecraft will undock from the Poisk module on Tuesday, November 19. Although NASA will not stream this undocking event, it marks another step in efficient cargo operations at the ISS.

What Happens Next?

Once docked, the Progress 90 spacecraft will remain attached to the ISS for approximately six months, providing continuous support to the crew. When it completes its mission, the spacecraft will carry away any used supplies and cargo, ensuring a tidy and efficient living environment aboard the station. It will then safely re-enter Earth’s atmosphere, disposing of invaluable trash generated during the mission.

The Role of the ISS in Space Exploration

For over 24 years, NASA has played a key role in maintaining a continuous human presence in low Earth orbit, enabling groundbreaking research and scientific exploration that simply cannot be achieved on our home planet. The ISS serves as a unique laboratory that allows for experiments in microgravity, helping scientists make discoveries that will not only benefit life on Earth but also pave the way for future space exploration.

The station is poised to support NASA’s ambitious goals for the Artemis program, which aims to return humans to the Moon and expand our presence in the solar system. Ultimately, this sustained effort will guide us toward the dream of human exploration of Mars.

Join the Journey!

As we look forward to another exciting chapter in space travel with the Progress 90 mission, we encourage everyone to join the conversation. Share your thoughts, watch the launch, engage with fellow enthusiasts online, and marvel at the boundaries that humanity is pushing through science and collaboration. Space is within our reach, and every mission takes us one step closer to understanding our universe!

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Together, let’s celebrate the spirit of exploration and the collaborative advances in human innovation that make missions like this possible. See you on launch day! 🌌🚀✨

Get breaking news, images and features from the space station on Instagram, Facebook, and X.

Learn more about the International Space Station, its research, and its crew, at:

https://www.nasa.gov/station

The science section of our news blog STM Daily News provides readers with captivating and up-to-date information on the latest scientific discoveries, breakthroughs, and innovations across various fields. We offer engaging and accessible content, ensuring that readers with different levels of scientific knowledge can stay informed. Whether it’s exploring advancements in medicine, astronomy, technology, or environmental sciences, our science section strives to shed light on the intriguing world of scientific exploration and its profound impact on our daily lives. From thought-provoking articles to informative interviews with experts in the field, STM Daily News Science offers a harmonious blend of factual reporting, analysis, and exploration, making it a go-to source for science enthusiasts and curious minds alike. https://stmdailynews.com/category/science/