News
Untreated sewage and fertilizer runoff threaten the Florida manatee’s main food source, contributing to malnutrition
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.
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.
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.
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.
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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News
How healthy is Sodastream?
The SodaStream Sparkling Water Maker is a device that forces carbon dioxide (CO2) gas (stored under pressure in a cylinder) into water, making it sparkling (fizzy)
Sodastream machines have been gaining popularity in recent years as an alternative to store-bought soft drinks. Not only are they more environmentally friendly, but they also offer several health benefits compared to traditional sodas.
Reduced Sugar Intake
One of the most significant health benefits of using a Sodastream machine is reducing sugar intake. Traditional sodas are loaded with sugar, and excessive sugar intake can lead to weight gain, obesity, and other health problems such as Type 2 diabetes. With a Sodastream machine, you can control the amount of sugar you add to your drink, allowing you to enjoy a refreshing beverage without the harmful effects of excessive sugar consumption.
No Artificial Sweeteners
Many store-bought soft drinks contain artificial sweeteners, which can have negative health effects such as headaches and digestive problems. Sodastream machines, on the other hand, allow you to use natural sweeteners such as fruit extracts, honey or agave nectar, giving you a healthier and more natural alternative.
No Preservatives
Another advantage of using a Sodastream machine is that you can avoid preservatives commonly found in store-bought soft drinks. Preservatives such as sodium benzoate and potassium sorbate have been linked to health problems such as cancer and allergies. By making your own drinks, you can avoid these harmful additives and enjoy a healthier, preservative-free beverage.
Eco-Friendly
In addition to the health benefits, using a Sodastream machine is also environmentally friendly. Traditional soft drinks are packaged in plastic bottles or cans, which contribute to environmental pollution. With a Sodastream machine, you can reuse the same bottle multiple times, reducing waste and helping to reduce your carbon footprint.
Variety
Finally, Sodastream machines offer a wide variety of flavors and options, allowing you to customize your drink to your liking. You can mix and match different flavors or create your own unique blends, giving you a healthier and more enjoyable alternative to traditional sodas.
In conclusion, Sodastream machines offer several health benefits compared to traditional store-bought soft drinks. By reducing sugar intake, avoiding artificial sweeteners and preservatives, and being eco-friendly, they offer a healthier and more sustainable alternative to traditional soft drinks. Moreover, with a wide variety of flavors and options, you can customize your drink to your liking, making it a fun and enjoyable way to stay healthy.
Consumer Corner
Behind the Product: What Sustainability Looks Like in Beauty Development
Beauty Development: Shoppers want to know what ingredients are used, how items are packaged and whether the production process includes thoughtful choices. Beauty brands are taking note, and sustainability is increasingly shaping decisions across sourcing, packaging, production, shipping, storage and replenishment.
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(Feature Impact) Shoppers are paying closer attention to the products they bring into their homes. They want to know what ingredients are used, how items are packaged and whether the production process includes thoughtful choices. Beauty brands are taking note, and sustainability is increasingly shaping decisions across sourcing, packaging, production, shipping, storage and replenishment.
Responsible product lines rarely come from sweeping change. They are built through smaller, connected choices made throughout development. Packaging, ingredient sourcing and production planning influence how a product performs, how much waste it creates and how sustainably products can be produced.
Consider this beauty sustainability information from Laura Badcock, Chief Operating Officer of NourishUs Naturals.
Why packaging matters beyond appearance
“Packaging is often the first thing shoppers notice,” Badcock said. “It can shape how someone feels about a product before they ever try what’s inside.”
A package should look appealing, though appearance is only part of the equation. It also needs to protect the product, travel safely, store well and hold up through regular use. Once the product is finished, the packaging should allow easy recycling, refilling or responsible disposal.
There is no single packaging option that works best for every beauty product. A lightweight container may reduce shipping weight. A refillable option may stay in use longer. A recyclable material may work well in one area but create challenges in another if local recycling systems cannot process it. Even packaging that appears sustainable can create problems in practice if it leaks, breaks or requires excess shipping materials.
Why ingredient sourcing matters
“Ingredient lists have become an important part of how people evaluate beauty products,” Badcock said. “Shoppers often look for familiar oils, butters, botanical extracts and information about how ingredients were sourced, which plays a major role in the environmental impact.”
A product’s environmental footprint is influenced by many factors, including shipping distance, processing methods, storage conditions and supplier practices.
These factors can also affect product consistency and ingredient availability over time. Beauty brands working with wholesale skin care suppliers or private label manufacturers often need to balance ingredient goals with sourcing reliability and production needs.
How better planning can lead to less waste
“Packaging and ingredients are usually the first things people associate with sustainability, but how much product gets made, stored and discarded matters, too,” Badcock said.
Overproduction is one of the biggest hidden sources of waste in beauty and personal care. Products that sit too long in storage may eventually expire or remain unsold. Excess inventory can also create additional packaging waste, warehousing needs and disposal costs.
Smaller batch sizes give producers more room to adjust as trends or demand shift, and producing closer to expected sales windows helps reduce long storage periods and unnecessary waste. Testing new products in smaller volumes and restocking based on actual demand makes overproduction less likely.
How sustainable beauty choices are connected
Packaging, ingredient sourcing and production planning are closely connected throughout development.
“A packaging choice can affect shipping weight, storage needs and whether a package can be refilled,” Badcock said. “Ingredient choices can influence sourcing timelines and how products need to be stored. Production planning affects how much material gets used and how much product could eventually go unsold.”
Beauty shoppers want more transparency around sustainability claims
Sustainability claims carry less weight when those claims aren’t explained in practice.
This shift is pushing many beauty brands to focus more heavily on traceability, supplier relationships and clearer product information. Transparency is becoming part of the customer experience itself.
More responsible product lines are built over time
Responsible beauty products come together through ongoing choices around packaging, sourcing, production and inventory planning. For shoppers, those choices influence the products they bring into their homes.
“The brands that build sustainability into early decisions tend to have the easiest time maintaining it later,” Badcock said. “Once supplier relationships, packaging formats and production routines are in place, small adjustments are far easier than major changes. Treating sustainability as part of product development from the beginning, rather than something to fix later, is what makes it work in practice.”
To find more information on the intersection of beauty and sustainability, visitNourishUsNaturals.com.
Photo courtesy of Shutterstock
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Automotive
EPA removal of vehicle emissions limits won’t stop the shift to electric vehicles, but will make it harder, slower and more expensive
The EPA’s move to rescind the 2009 “endangerment finding” and roll back vehicle emissions limits won’t stop the shift to electric vehicles—but it will slow adoption, raise costs, and increase climate and public health harms.
Alan Jenn, University of California, Davis
The U.S. government is in full retreat from its efforts to make vehicles more fuel-efficient, which it had been prioritizing, along with state governments, since the 1970s.
The latest move came on Feb. 12, 2026, when President Donald Trump and the Environmental Protection Agency issued a new rule rescinding the landmark “endangerment finding,” and reversing various emissions limits on cars and trucks. The 2009 finding stated that greenhouse gases pose a threat to public health and welfare. If the new rule stands up in court and is not overruled by Congress, it would undo a key part of the long-standing effort to limit greenhouse gas emissions from vehicles.
As a scholar of how vehicle emissions contribute to climate change, I know that the science behind the endangerment finding hasn’t changed. If anything, the evidence has grown that greenhouse gas emissions are warming the planet and threatening people’s health and safety. Heat waves, flooding, sea-level rise and wildfires have only worsened in the decade and a half since the EPA’s ruling.
Regulations over the years have cut emissions from power generation, leaving transportation as the largest source of greenhouse gas emissions in the U.S.
The scientific community agrees that vehicle emissions are harmful and should be regulated. The public also agrees, and has indicated strong preferences for cars that pollute less, including both more efficient gas-burning vehicles and electric-powered ones. Consumers have also been drawn to electric vehicles thanks to other benefits such as performance, operation cost and innovative technologies.
That is why I believe the EPA’s move will not stop the public and commercial transition to electric vehicles, but it will make that shift harder, slower and more expensive for everyone.
Putting carmakers in a bind
The most recent EPA rule about vehicle emissions was finalized in 2024. It set emissions limits that can realistically only be met by a large-scale shift to electric vehicles.
Over the past decade and a half, automakers have been building up their capability to produce electric vehicles to meet these fleet requirements, and a combination of regulations such as California’s zero-emission-vehicle requirements have worked together to ensure customers can get their hands on EVs. The zero-emission-vehicle rules require automakers to produce EVs for the California market, which in turn make it easier for the companies to meet their efficiency and emissions targets from the federal government. These collectively pressure automakers to provide a steady supply of electric vehicles to consumers.
The new EPA move would undo the 2024 EPA vehicle-emissions rule and other federal regulations that also limit emissions from vehicles, such as the heavy-duty vehicle emissions rule.
The possibility of a regulatory reversal puts automakers into a state of uncertainty. Legal challenges to the EPA’s shift are all but guaranteed, and the court process could take years.
For companies making decade-long investment decisions, regulatory stability matters more than short-term politics. Disrupting that stability undermines business planning, erodes investor confidence and sends conflicting signals to consumers and suppliers alike.
A slower roll
The Trump administration has taken other steps to make electric vehicles less attractive to carmakers and consumers.
The White House has already suspended key provisions of the Inflation Reduction Act that provided tax credits for purchasing EVs and halted a US$5 billion investment in a nationwide network of charging stations. And Congress has retracted the federal waiver that allowed California to set its own, stricter emissions limits. In combination, these policies make it hard to buy and drive electric vehicles: Fewer, or no, financial incentives for consumers make the purchases more expensive, and fewer charging stations make travel planning more challenging.
Overturning the EPA’s 2009 endangerment finding would remove the legal basis for regulating climate pollution from vehicles altogether.
But U.S. consumer interest in electric vehicles has been growing, and automakers have already made massive investments to produce electric vehicles and their associated components in the U.S. – such as Hyundai’s EV factory in Georgia and Volkswagen’s Battery Engineering Lab in Tennessee.
Global markets, especially in Europe and China, are also moving decisively toward electrifying large proportions of the vehicles on the road. This move is helped in no small part due to aggressive regulation by their respective governments. The results speak for themselves: Sales of EVs in both the European Union and China have been growing rapidly.
But the pace of change matters. A slower rollout of clean vehicles means more cumulative emissions, more climate damage and more harm to public health.
The EPA’s move seeks to slow the shift to electric vehicles, removing incentives and raising costs – even though the market has shown that cleaner vehicles are viable, the public has shown interest, and the science has never been clearer. But even such a major policy change can’t stop the momentum of those trends.
This is an updated version of an article originally published Aug. 5, 2025.
Alan Jenn, Associate Professor of Civil and Environmental Engineering, University of California, Davis
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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