Why aren't we talking about the environmental impact of the wall Trump says he will build?

I raised the subject in the comments to the earlier post about the wall. I said: "Am I the only one who worries about the wall as aesthetically and ecologically troubling?" John Henry said:

Why aesthetically troubling? You have no idea yet what it will look like, do you? I suspect that in some placed it may be a wall, in others a fence, in others natural barriers. No wall is needed when the border is at the base of a 100' cliff, for example.

Ecologically troubling? You are the first person I have ever heard ask that. Could you elaborate?

I think you are the first person I've seen have trouble with the what the wall looks like, too.

I said that I was concerned about "a wall slicing through such a long huge length of" of America, "imping[ing] on nature so brutally" and that I worried about "the plants and animals that flow back and forth within those areas." I didn't remember hearing anyone else bring this up, but I had no trouble finding this Newsweek article from a few days ago: "THE ENVIRONMENTAL IMPACT OF THE U.S.-MEXICO BORDER WALL." There's a photograph with the caption: "Javelina (Pecari tajacu) turn away after looking for 100 yards for a place to cross the U.S.-Mexico border fence near the San Pedro river corridor in Arizona in July 2008."

[T]he Rio Grande Valley [is] one of the most biodiverse places in North America, with more than 700 species of vertebrates alone. It sits at the convergence of two major flyways for migratory birds... some 500 different bird species.

Before construction of the fence began in 2009, a list of species likely to be affected was prepared by the Texas Parks and Wildlife Department. It included 10 plants and animals on federal and state endangered lists, 23 on Texas’s threatened list and dozens of species of concern. But the wall went up anyway.

Species with small populations and specialized habitats have suffered the most from the disruption, says Jesse Lasky, an assistant professor of biology at Penn State. He co-authored a 2011 study reporting that the barrier reduced the range for some species by as much as 75 percent. Small range size is associated with a higher risk of extinction, and, according to the study, the wall puts additional stress on Arroyo toads, California red-legged frogs, black-spotted newts and Pacific pond turtles—all listed as endangered or threatened by the International Union for Conservation of Nature—and the jaguarondi, a small wildcat endangered in the U.S. and threatened in Mexico.

Other research concluded that the barrier disrupts movements and distribution of the ferruginous pygmy-owl and bighorn sheep and could isolate small populations of large mammals in Arizona’s Sky Island region, including black bears and pumas. Such isolation reduces exchange of genetic material and makes the animals more vulnerable to disease.

Barrier posts cross the Nature Conservancy’s Lennox Foundation Southmost Preserve near Brownsville, and staffers there have seen increasing numbers of white-tailed deer and javelina on the property. That isn’t a good thing; it likely means, says Laura Huffman, director of the Nature Conservancy’s Texas branch, that wildlife squeezed out of its natural habitat is forced onto the preserve—and not that the overall number of these animals has increased.

“The fence is the very definition of habitat fragmentation, the very definition of what inhibits free movement of wildlife within its natural habitat,” Huffman says.

Much more at the link.