There's a Paul McCartney quote popular with veg-heads: "If slaughterhouses had glass walls, everyone would be a vegetarian." It may not be quite as simple as all that, but he's definitely got a point.

For a little over 10 years, groups such as Mercy for Animals, the Humane Society of the United States, and Compassion Over Killing have conducted undercover investigations into abuses and rules violations on factory farms, and publicized what they've documented to lobby for change.

It's worked: Individual campaigns have resulted in business closures, criminal charges, and even broader changes in social behavior. That has got Big Animal Ag scared.

So it has done what Big Ag does best: crafted legislation and lobbied for it. State farm-protection laws, or "ag-gags," as The New York Times' Mark Bittman lovingly called them, come in many different forms, mixing various combinations of restrictions on undercover filming and activist access to farms and slaughterhouses. Some of the laws give a nod to the value of whistleblowers but require that damning footage be handed over to law enforcement within a day or two, immediately blowing the cover of investigations that would typically last from two to six weeks.

Environmental activist Daniel McGowan is out of prison, but he’s not out of the woods. He was incarcerated for seven years for his alleged involvement in arson at an Oregon lumber company, then thrown back in prison for writing about how his beliefs got him branded  a terrorist. He's now been released, but only after being told he can't publish his opinions or talk to the press.

McGowan is the central figure in the 2012 Oscar-nominated documentary If a Tree Falls, which details the lead-up to his prison sentence for arson credited to the Earth Liberation Front. He was released this past December to a halfway house in New York City.

McGowan spent more than two years of his sentence in a Communication Management Unit (CMU), where his contact with the outside world through letters and phone calls was highly restricted. In a piece published in The Huffington Post on April 1, McGowan explains how he ended up in the CMU: The Federal Bureau of Prisons (BOP) didn't like what he was writing about environmental activism from his cell. "In short, based on its disagreement with my political views, the government sent me to a prison unit from which it would be harder for me to be heard, serving as a punishment for my beliefs," he writes. McGowan learned these details after filing a lawsuit on behalf of himself and other CMU prisoners. Through the lawsuit, the BOP was forced to reveal some damning internal memos. McGowan:

The following speech is listed in these memos to justify my designation to these ultra-restrictive units:

My attempts to "unite" environmental and animal liberation movements, and to "educate" new members of the movement about errors of the past; my writings about "whether militancy is truly effective in all situations"; a letter I wrote discussing bringing unity to the environmental movement by focusing on global issues; the fact that I was "publishing [my] points of view on the internet in an attempt to act as a spokesperson for the movement"; and the BOP's belief that, through my writing, I have "continued to demonstrate [my] support for anarchist and radical environmental terrorist groups."

On April 4, three days after McGowan's post was published, the BOP responded by -- what else? -- throwing him back in prison for talking about what he wasn't supposed to talk about.

The oil industry isn't the only business flexing its muscle in Washington. The Business for Innovative Climate and Energy Policy coalition, aka BICEP, today released a “Climate Declaration" urging Congress to do some heavy lifting on climate change and "asserting that a bold response to the climate challenge is one of the greatest American economic opportunities of the 21st century.” Signatories include Nike, Starbucks, eBay, and 30 other companies, with a combined annual revenue of about $450 billion.

“The signers of the Climate Declaration have a clear message for Washington: Act on climate change. We are, and it’s good for our businesses,” Anne Kelly, director of BICEP, said in a statement.

From the statement: "The signatories of the Climate Declaration are calling for Congress to address climate change by promoting clean energy, boosting efficiency and limiting carbon emissions -- strategies that these businesses already employ within their own operations."

Though the clean coalition's efforts are aimed at policymakers, its business is really aimed at the rest of us. And that's where this effort starts to feel a bit self-serving.

The Salton Sea was once California's biggest tourist attraction -- now, with some of the highest rates of unemployment in the country, it's the state's rustiest, dustiest failed region. With water usage in Southern California at a premium, the accidentally human-made sea is drying up, with its only significant inflow coming from nearby farm runoff. It's still vital wetlands for 400 species of migratory birds, but the sea is poised to evaporate into a 365-square-mile dust bowl right next to Palm Springs within just a few years. And while it may not be blowing airborne toxins all over southern California and Arizona just yet, it's already assaulting Los Angeles with its powerful poison "odor events," which scientists predict could only grow more intense. (You can read some background on the Salton Sea in my comic above, an excerpt from the [free!] December issue of Symbolia Magazine.)

Now for the first time in a while, politicians are actually sounding hopeful about mitigating the sea's degradation. (Sorry, disaster tourists.) “We have a united vision. For the first time, there’s a chance to make some progress,” says one local county supervisor. But they have very different ideas on how to do it.

Florida has the world's largest population of manatees, around 5,000 of the adorable, curious, endangered sea cows. In 1996, a red algae bloom killed 151 of them. Until this year, it was the most lethal red tide on record. But Florida has outdone itself this time.

So far this year, 241 manatees have been killed by a red algae bloom off the southwestern coast of the state. All across Florida, at least 463 manatees have died from a variety of causes, "more deaths than had been recorded in any previous comparable period,” reports The New York Times — more than 9 percent of the population in just over three months.

Wine grapes are about as sensitive as your head the morning after you've tied one on with a bottle of Bordeaux: They need just the right climate to thrive. And that climate, of course, is changing.

A new study published in the journal Proceedings of the National Academy of Sciences predicts the rapid decline of wine-growing regions from California to Australia -- quite the headache for the $290-billion-a-year global wine industry.

The Guardian reports:

Researchers predict a two-thirds fall in production in the world's premier wine regions because of climate change. ...

The scientists used 17 different climate models to gauge the effects on nine major wine-producing areas. They used two different climate futures for 2050, one assuming a worst-case scenario with a 4.7C (8.5F) warming, the other a 2.5C increase.

Both forecast a radical re-ordering of the wine world. The most drastic decline was expected in Europe, where the scientists found a 85% decrease in production in Bordeaux, Rhone and Tuscany.

The future was also bleak for wine growing areas of Australia, with a 74% drop, and California, with a 70% fall

Lead-free gasoline: It's pretty great, as far as gasoline-without-extra-toxins goes. But even though we've made great strides in reducing lead pollution over the last few decades, America's still full of the stuff.

More than half a million American children under 5, or 1 in 38 young kids, have low-grade lead poisoning, according to a new report from the Centers for Disease Control and Prevention. The surveys from 2007 to 2010 showed an 8.6 percent decrease in childhood lead poisoning compared to 1999-2002.

Until last year, the CDC only tracked people with 10 micrograms of lead per deciliter of blood, considered the threshold for lead poisoning by the CDC, World Heath Organization, and the American Academy of Pediatrics. But five micrograms per deciliter is considered enough to potentially cause damage.

Those approximately 535,000 kids aren't really a representative sample of American youth, though.

After much hemming, hawing, and Hulking, some crack reporters have solved the case of the Monsanto rider, the new law that gives GMO crops legal immunity.

It was Sen. Roy Blunt (R-Mo.) in the boardroom with the inappropriate relationships with Big Ag lobbyists!

Politico first broke the Blunt story, but Tom Philpott at Mother Jones highlights just how cozy the Missouri senator is with the GMO giant, who he "worked with" to write and pass the rider.

"If Sen. Blunt plans to continue carrying Monsanto's water in the Senate, the company will have gained the allegiance of a wily and proven political operator," he writes. More from MoJo:

The admission shines a light on Blunt's ties to Monsanto, whose office is located in the senator's home state. According to OpenSecrets, Monsanto first started contributing to Blunt back in 2008, when it handed him $10,000. At that point, Blunt was serving in the House of Representatives. In 2010, when Blunt successfully ran for the Senate, Monsanto upped its contribution to $44,250. And in 2012, the GMO seed/pesticide giant enriched Blunt's campaign war chest by $64,250.

So far, the thousands of barrels of tar-sands oil that spilled into a middle-class neighborhood in central Arkansas on Friday have driven 22 families from their homes and killed and injured a grip of local wildlife. So far, the oil hasn't contaminated the local lake or drinking water supply, according to ExxonMobil. It's a "major spill," according to the EPA, and the cause is so far still under investigation.

But since it's not oil-oil, ExxonMobil hasn't paid into the government clean-up fund that would help bankroll the epic scrub-down necessary to rid poor unsuspecting Mayflower, Ark., of all that bitumen.

"A 1980 law ensures that diluted bitumen is not classified as oil, and companies transporting it in pipelines do not have to pay into the federal Oil Spill Liability Trust Fund," writes Ryan Koronowski at Climate Progress. "Other conventional crude producers pay 8 cents a barrel to ensure the fund has resources to help clean up some of the 54,000 barrels of pipeline oil that spilled 364 times last year."

Here, this helpful infographic might clear things up for you:

California's super-productive farmland is being overrun by development projects. Sprawly exurban housing development and even solar projects threaten to gobble up all the Golden State's arable land. As of 2007, California was home to more than 25 million acres of cropland, but that's shrinking by more than 1 percent each year, according to the American Farmland Trust.

All's not lost, though: Two proposed bills could give a boost to California agriculture big and small, and potentially change the way the Golden State develops over the coming years.