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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Every year on the first Friday in August, beer lovers around the world come together to celebrate International Beer Day. In 2026, the celebration falls on Friday, August 7, offering the perfect opportunity to discover new brews, support local breweries, and enjoy time with friends.
Founded in 2007 in Santa Cruz, California, International Beer Day has grown into a global event observed in dozens of countries. The celebration recognizes not only the beverage itself but also the brewers, bartenders, servers, and everyone who helps bring beer from the brewery to your glass.
Whether you’re a fan of crisp lagers, hoppy IPAs, rich stouts, refreshing wheat beers, or adventurous sour ales, International Beer Day is a great excuse to step outside your comfort zone and sample something new. Many breweries and pubs celebrate with special releases, tasting flights, live entertainment, brewery tours, and food pairings.
As the craft beer movement continues to flourish across the United States, this annual celebration is also a reminder of the creativity and community that local breweries bring to neighborhoods large and small.
If you decide to celebrate, remember to drink responsibly, arrange for a designated driver or rideshare if needed, and support your favorite local brewery.
Cheers to International Beer Day!
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Economy
Donor States vs. Recipient States: Where Does Your Federal Tax Dollar Go?
Some states send Washington more money than they receive, while others receive considerably more federal spending. Here’s what “donor state” really means—and why the numbers don’t necessarily measure government dependency.
Every year, Americans send trillions of dollars to Washington through income taxes, payroll taxes, corporate taxes and other federal revenues. The federal government then sends trillions back across the country through Social Security, Medicare, Medicaid, military spending, federal salaries, contracts, grants, infrastructure projects and dozens of other programs.
But the money doesn’t necessarily return to the states in the same proportions in which it was collected.
That’s where the terms “donor state” and “recipient state” come in.
What Is a Donor State?
Simply put, a donor state sends more money to the federal government than it receives back in federal spending.
Imagine taxpayers and businesses in a state contribute $100 billion to the federal government during a year. If federal spending within that state totals only $80 billion, the state has effectively contributed $20 billion more to the federal government than it received.
A recipient state experiences the opposite: federal expenditures within the state exceed the amount collected there in federal revenue.
These aren’t official federal government classifications, however. They’re terms commonly used by researchers analyzing the flow of money between individual states and Washington.
Only Three Donor States in 2023?
According to an August 2025 analysis from the Rockefeller Institute of Government using preliminary federal fiscal year 2023 data, only three states had negative balances—meaning they contributed more federal revenue than they received in federal expenditures.
Those states were:
New Jersey: approximately $18.9 billion more contributed than received.
Massachusetts: approximately $6.8 billion more contributed than received.
Washington: approximately $54 million more contributed than received.
At first glance, that might suggest nearly every other state depends financially on those three states.
The reality is considerably more complicated.
COVID Changed the Numbers
Historically, several wealthy states—including California and New York—have frequently appeared on the donor side of the equation.
The enormous federal response to the COVID-19 pandemic disrupted that pattern.
Trillions of dollars in extraordinary federal spending flowed into states through stimulus payments, business assistance, unemployment programs, healthcare funding, state and local government assistance and other programs.
Even after the emergency phase of the pandemic ended, some of those expenditures continued influencing federal balance-of-payments calculations.
That’s one reason examining a single year can produce a misleading picture.
California: Recipient Today, Historical Donor
California provides perhaps the best example.
In fiscal year 2023, California technically received slightly more federal spending than it contributed—approximately $342 more per person.
But look at the longer-term numbers and the picture changes.
Using a nine-year average that excludes COVID-related spending, Rockefeller Institute researchers calculated California’s average balance at approximately negative $29 billion.
In other words, over a more typical period, California has historically contributed substantially more to the federal government than it received.
Its enormous economy, high incomes and large number of taxpayers generate tremendous amounts of federal revenue.
New York Tells a Similar Story
New York has also historically ranked among America’s major donor states.
Yet in 2023, New York had a positive federal balance of approximately $13.3 billion, receiving roughly $1.04 in federal expenditures for every $1 it contributed.
Researchers attributed much of the change from New York’s historical pattern to lingering pandemic-era federal expenditures.
As those programs disappear from the calculations, New York could return to its traditional position as a donor state.
Arizona Is a Net Recipient
Arizona presents a different picture.
Over the Rockefeller Institute’s nine-year analysis, Arizona averaged a positive federal balance of approximately $44.5 billion.
Even after excluding COVID-related spending, Arizona’s average remained positive at roughly $35.3 billion.
That means federal expenditures flowing into Arizona have substantially exceeded federal revenue collected from the state.
But that doesn’t mean Arizona simply receives tens of billions of dollars in “welfare.”
Federal spending includes far more than public assistance.
Arizona hosts military installations, federal lands and agencies, defense and aerospace operations, veterans programs and a significant retiree population receiving Social Security and Medicare.
All of those expenditures count toward the state’s federal balance.
Texas Receives More Than It Sends
Texas also had a substantial positive balance in 2023.
Federal expenditures exceeded revenues collected from Texas by approximately $80 billion, making it one of the country’s largest net recipients in total dollars that year.
Again, the number needs context.
Texas is home to major military installations, NASA operations, defense contractors, federal infrastructure projects and millions of Social Security and Medicare recipients.
Those federal dollars all count as money flowing back into the state.
The Surprising Leader: Virginia
If recipient-state status simply meant dependency on federal welfare programs, Virginia would seem like an unlikely candidate to lead the country.
Yet Virginia recorded the nation’s largest positive federal balance in 2023 at approximately $145.4 billion.
Why?
Location.
Virginia sits next to Washington, D.C., and contains an enormous concentration of federal employees, military installations, government contractors and defense spending.
Neighboring Maryland ranked second with a positive balance of approximately $81.1 billion.
The numbers illustrate why federal balance-of-payments statistics should not automatically be interpreted as measurements of welfare dependency.
A recipient state isn’t necessarily a “welfare state.” Federal expenditures include Social Security, Medicare, military installations, defense contracts, federal salaries, research, infrastructure, grants and other programs.
Where Does the Federal Money Actually Go?
Federal expenditures flowing into a state can include:
- Social Security
- Medicare and Medicaid
- Military bases and personnel
- Defense contracts
- Federal employee salaries
- Highway and transit funding
- Scientific and university research
- Agricultural programs
- Veterans benefits
- Disaster assistance
- Federal grants
- Infrastructure projects
- Federal agency operations
A state containing a large military installation, federal laboratory or government agency can therefore receive billions of federal dollars without that money having anything to do with traditional public assistance programs.
Why Wealthier States Often Become Donors
Federal income taxes are progressive.
People with higher incomes generally pay a larger percentage of their income in federal income taxes.
States containing large concentrations of high-income households and highly profitable companies can consequently generate enormous amounts of federal revenue.
That helps explain why states such as California, New York, New Jersey and Massachusetts have historically appeared frequently among net contributors.
The federal government doesn’t earmark the taxes collected in California exclusively for California.
The money enters the national treasury and helps finance programs throughout the United States.
In that sense, federal taxation intentionally redistributes resources geographically as well as economically.
So Are Donor States “Subsidizing” Recipient States?
In a broad accounting sense, yes.
Federal revenue collected disproportionately from some states helps finance federal expenditures occurring elsewhere.
But describing the relationship simply as one state “paying for” another leaves out important context.
Federal spending follows national priorities rather than state borders.
A Navy base in Virginia protects the entire country. NASA facilities in Texas conduct missions funded by taxpayers nationwide. Social Security benefits paid to a retiree in Arizona may reflect payroll taxes that person paid while working decades earlier in California, Illinois or New York.
Americans and businesses also move between states throughout their lives.
The federal system was never designed to ensure that every dollar collected within a state’s borders would eventually return to that same state.
The Bigger Picture
The donor-state debate is often used as political ammunition, particularly when politicians argue about which parts of the country are supporting others.
The numbers are real, but they require context.
A state can move from donor to recipient status because of a recession, natural disaster, military spending, demographic changes, infrastructure investments or extraordinary events such as the COVID-19 pandemic.
That’s why examining several years of data generally tells us more than looking at a single year.
Ultimately, the donor-versus-recipient calculation reveals something fundamental about the United States:
Federal taxes don’t remain where they’re collected.
They become part of a national pool used to fund programs, obligations and investments across all 50 states.
And depending on where you live, your state may be putting more into that pool—or taking more out—at any particular moment.
Related External Links
- Rockefeller Institute of Government – 2025 Balance of Payments Report
- USAspending.gov – Explore Federal Government Spending
- USAspending.gov – Federal Spending Guide
- IRS – Individual Income Tax Data by State
- IRS – Federal Taxes Collected by State
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Food Truths
The Truth About the “Chemical” in McDonald’s Burger Buns: Should Consumers Be Concerned?
What’s in the Burger Buns:The “yoga mat chemical” controversy changed how consumers view food additives. Here’s what azodicarbonamide is, why McDonald’s removed it, and what the science actually says.
For years, headlines and social media posts have warned consumers about a so-called “yoga mat chemical” found in hamburger buns served by major fast-food chains. The claims sparked widespread concern, prompted petitions, and eventually led several restaurant companies—including McDonald’s—to change their recipes.
But what was the chemical, and is there actually a health risk today?
What Was the Controversial Ingredient?
The ingredient at the center of the controversy was azodicarbonamide (ADA), a chemical used as a dough conditioner. It helped improve the texture of bread, making dough easier to handle and producing softer, more consistent buns.
Ironically, the same compound is also used in manufacturing certain foamed plastics, including some yoga mats and shoe soles. That connection gave rise to the viral nickname, “the yoga mat chemical.”
While the comparison was technically accurate, it also lacked important context. Food-grade azodicarbonamide and industrial applications are very different, and many chemicals have multiple uses across industries.
Why Did People Become Concerned?
The concern wasn’t simply that ADA was used in food. Scientists focused on what happens during baking.
When bread is baked, most azodicarbonamide breaks down into other compounds. Some laboratory studies involving animals raised questions about one of these breakdown products, called semicarbazide (SEM), when administered in high doses.
Those findings prompted some countries to take a more cautious regulatory approach.
Why Is It Banned in Some Countries?
The European Union and Canada do not permit azodicarbonamide as a flour treatment agent. Their food safety policies often follow the precautionary principle, removing ingredients when safer alternatives exist or when scientific uncertainty remains.
In contrast, the U.S. Food and Drug Administration has determined that azodicarbonamide is safe when used within approved limits.
These differing regulations don’t necessarily mean one side believes the ingredient is dangerous while the other believes it is harmless. Instead, they reflect different philosophies about regulating food additives.
Does McDonald’s Still Use It?
No.
McDonald’s removed azodicarbonamide from its U.S. hamburger buns in 2014 following growing consumer demand for simpler ingredient lists.
Today’s buns no longer contain the ingredient, joining a broader trend among food manufacturers to eliminate additives that have become controversial with consumers.
Are There Other Ingredients Consumers Should Know About?
Modern commercial bread still contains ingredients designed to improve freshness, texture, and shelf life.
These may include:
- Calcium propionate to prevent mold
- Ascorbic acid (Vitamin C) as a dough conditioner
- Enzymes that improve consistency
- Emulsifiers that help maintain softness
These ingredients have been evaluated by food safety agencies and are generally recognized as safe when used according to regulations.
The Bigger Health Picture
Nutrition experts generally agree that focusing on one ingredient can distract from the larger issue.
The greatest health risks associated with fast food are more closely linked to:
- High sodium intake
- Excess saturated fat
- Added sugars
- Large portion sizes
- Frequent consumption of ultra-processed foods
An occasional fast-food meal is unlikely to determine someone’s long-term health. Overall dietary patterns, physical activity, sleep, and other lifestyle factors have a much greater impact.
Consumer Awareness Is Changing the Food Industry
Whether or not an ingredient poses a measurable health risk, public concern can influence corporate decisions.
Over the past decade, many food companies have reformulated products to remove controversial ingredients, reduce artificial additives, and simplify ingredient labels. In many cases, those changes have been driven as much by consumer preferences as by regulatory requirements.
The Bottom Line
The “yoga mat chemical” story captured public attention because it combined science, food safety, and memorable marketing. While azodicarbonamide was once used in some hamburger buns, including those supplied to McDonald’s, the company removed it from its U.S. buns years ago.
Current evidence suggests consumers are better served by paying attention to their overall diet rather than worrying about a single ingredient that has already disappeared from many products.
Being an informed consumer means looking beyond the headlines, understanding the science, and recognizing that nutrition is about the complete picture—not just one ingredient.
Related External Links
- U.S. FDA – Food Additives & GRAS Ingredients Information for Consumers
- U.S. FDA – Food Additives and Petitions
- FDA – Azodicarbonamide (ADA) Food Substance Database
- Electronic Code of Federal Regulations – 21 CFR §172.806 (Azodicarbonamide)
- FDA – Types of Food Ingredients and Why They’re Used
- Health Canada – Permitted Flour Treatment Agents
- McDonald’s USA – Nutrition Calculator & Ingredient Information
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