Species Are on the Move and Northward Bound—Then What?

Hey there, plankton—what are your plans?

As all manner of living creatures, from invertebrates to trees to mammals, start heading toward the poles, habitat range is becoming a hot topic (precisely because things are heating up). Most studies are focused on the journeys themselves, but Jens Hegg, a PhD candidate at the University of Idaho, thinks one question getting short shrift is what these species will do once they get to their destination. The shifts won’t happen all at once. We’re not in store for a musical-chairs shuffle with each species arriving at their new homes at the same time. The drifts will happen at different rates, and on move-in day, the migrants won’t be settling into stable ecosystems.

Hegg calls for more research on what lies ahead for a species and who its new neighbors might be. That way, ecosystem managers could get a better idea of who’s coming to town and then, perhaps, make things more hospitable.

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Shuck that oyster, then make a buck?

If you’re anything like me, you spend your free summer days plowing through soft-shelled lobsters and clams, then tossing their shells into a bucket at your elbow. And you’ve probably never thought about recycling them. But chemists Ning Yan and Xi Chen do. In Nature this week, they suggest that instead of throwing these exoskeletons away, we put them to work. Worldwide, we discard up to eight million tons of crab, lobster, and shrimp shells each year, even though they contain lots of useful stuff. Calcium carbonate makes a good chalk for pharmaceutical drug pills, chitin can be used in cosmetics and textiles, and protein can help feed our livestock.

Current methods for refining shells are destructive and wasteful, but the scientists argue that it’s time we figured out a sustainable, efficient way to extract these substances from our seafood waste. If I’d known chitin can go for up to $200 per kilogram, I would’ve saved up all those buckets of shells for a surfboard.

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Stop making trees the fall guys.

In 2006, an outbreak of E. coli in packaged spinach killed three people and sickened many others. The cause was never officially determined, but the bacterial strain was traced back to a farm on California’s central coast, where it was found in the feces of cattle and wild pigs nearby.

Since then, one strategy for preventing future outbreaks has been to clear wild vegetation surrounding farms, the idea being that fewer animals would approach the fields without trees and bushes to hang out and hide in, and that way their E. coli poops could be averted. But a new study published Monday in Proceedings of the National Academy of Sciences says this actually hasn’t helped reduce E. coli or Salmonella contamination in produce, water, or rodents around farms. In fact, pathogenic E. coli in leafy green vegetables has increased since the 2006 outbreak. And over time, growers who removed the most wild vegetation had the largest increases in E. coli and Salmonella in their vegetables.

The authors suggest that vegetation surrounding farms ought to be left alone, because it’s probably more helpful than harmful—it can also provide habitat for bees, which pollinate crops, and prevent both agricultural and bacterial runoff. The study also found that levels of pathogenic E. coli were greater when fields were closer to grazeable land, a.k.a. cattle ranches. Hmm, perhaps we should address the levels of pathogens in our livestock rather than blame the trees.