USFWS: Mysterious 'Funnel Effect' Harming Wildlife at Unnamed Solar Plant

The U.S. Fish and Wildlife Service has weighed in on the proposed Palen Solar Electric Generating System, and the foremost federal wildlife agency says it's concerned about the impacts the project would have on wildlife ranging from eagles to lizards to monarch butterflies.

And the document refers to a mysterious "funnel effect of dead birds recently observed at another power tower facility," which USFWS does not identify but which is almost certainly -- in my professional opinion -- the Ivanpah Solar Electric Generating System (ISEGS), in urging greater caution on approving Palen.

But what's this "funnel effect"? And why the secrecy? We have some tentative guesses.

The background for the odd "funnel effect" mention is pretty important in its own right: USFWS is taking a relatively hard line on the Palen project, insisting on more thorough and more stringent monitoring and mitigation for wildlife impacts, and saying outright that the project proponents' wildlife science leaves something to be desired.

According to USFWS's comments on the project's Draft Supplemental Environmental Impact Statement (SEIS), the 500-megawatt solar power tower project proposed by BrightSource Energy and Abengoa for 3,896 acres of desert habitat along Interstate 10 west of Blythe would have significant impacts to Mojave fringe-toed lizards, bald and golden eagles, migratory birds, and migrating insects such as dragonflies and monarch butterflies.

USFWS is urging the Department of the Interior to revise the Draft SEIS to reflect recent testimony at a state agency hearing on the project's likely effect on the fringe-toed lizard's habitat. The agency also says that proposals by BrightSource and Abengoa to mitigate the project's likely harm to birds don't release the owners from legal liability under the Migratory Bird Treaty Act.

The USFWS comments, which were posted on the California Energy Commission (CEC) website Thursday, also point out that the Draft SEIS is deficient in addressing the solar project's likely effects on bald and golden eagles. USFWS says that the project proponents, doing business jointly as Palen Solar Holdings (PSH), conducted golden eagle surveys at the wrong time of year, thus understating the actual numbers of eagles that might be found on the site.

"Surveys conducted by PSH to assess use of the project site by golden eagles were conducted too late in the breeding season to ascertain with certainty the nesting status in 2013," says the document. "The first golden eagle observations began on April 8, 2013, a timing far later than that recommended by the Service. Palen Solar Holdings has characterized the use of the site by golden eagles as "low," notwithstanding documentation of nesting territories in Joshua Tree National Park, adjacent BLM-managed lands, and incidental observation of golden eagles proximal to [near] the project footprint."

What's more, notes USFWS, the Draft SEIS doesn't consider potential risks the project might pose to bald eagles, despite the fact that bald eagles were seen as recently as last month at a reservoir five miles west of the project site. Bald eagles also regularly migrate past the site on their way between the Colorado River, the Salton Sea, and the coast.

USFWS is recommending that PSH apply for programmatic take permits for bald and golden eagles similar to those the agency is introducing for wind turbine operators if a "robust analysis" of actual data shows the project will kill eagles more often than once every 33 years.

The agency's take on Palen's threat to other migratory birds is interesting:

Paraphrasing the USFWS: "we think it's a fine idea for PSH to preserve habitat elsewhere, but that doesn't get them off the hook for hurting birds protected under MBTA, and we have no idea whether the mitigation will even make a difference without knowing how many birds might end up colliding with the project's 170,000 billboard-sized mirrors or incinerated in the two towers' 900°F solar flux."

That mysterious funnel effect

USFWS also noted an issue ReWire hasn't covered before, and we suspect it has something to do with that funnel effect: the mortality of insects. The agency says the Palen solar project may have a serious effect on insects, based on experience at BrightSource's Ivanpah Solar Electric Generating System (ISEGS) site, now nearing completion in San Bernardino County. "Staff with the CEC reported large mortalities of insects killed during flux testing at the ISEGS site," says USFWS. "[A]mong those documented include migratory monarch butterflies and dragonflies."

A subsequent passage in the note on insects is an important summary of the relevance of insect mortalities to risk to other wildlife:

In its section on solar flux, USFWS recommends that third-party scientific monitoring be done for solar power tower projects "including Palen, ISEGS, and Rice Solar Reserve" to gather more information about the effect of solar flux on wildlife. Of the three, only ISEGS has generated solar flux, a hint at which "other solar power tower project" at which that "funnel effect" has been observed.

Here's the precise language USFWS used in mentioning the "funnel effect," in a discussion of USFWS' view that wildlife mortality monitoring at Palen should start earlier and be more comprehensive than is currently planned:

What does USFWS mean by "funnel effect"? It's hard to say for sure, but the food chain description above offers a hint. If insects are attracted by a power tower facility's bright light -- visble for many miles -- then those insects will converge on the project from across a wide area. Animals that eat insects are constantly on the lookout for their next meal, and a crowd of insects will attract a crowd of birds and bats. Small birds are an attractive food source to larger birds.

If you have a facility that both attracts an entire food chain and then poses a risk of mortality or injury to individual animals at any level in that chain, then you've created an ecosystem-wide population sink that can metaphorically "funnel" individual animals from a wide stretch of habitat to a single spot where they meet their demise.

This is educated speculation, of course. ReWire has contacted USFWS to see if they'll explain the "funnel effect" language in the comment on the Palen SEIS. We'll share their response with you as soon as we get it.

But here's the thing: USFWS is extremely cautious in its public statements on renewable energy projects, likely as a result of marching orders from the Department of the Interior similar to those that have quieted other Interior agencies.

When we reported in October that 30 birds were reported dead over the previous month at Ivanpah, it was a startling rise in reported deaths. It was also not particularly out of line with what you might expect after placing tens of thousands of heliostats on 4,000 acres of great songbird habitat.

If those 30 birds are a great enough loss to merit being described as a "funnel effect," then why the coy reference to "another power tower facility"? The deaths are on the public record, and the USFWS comment baldly refers to wildlife mortality at ISEGS elsewhere in the document -- including more than one bat mortality.

Or is there something else at play here? Some other reason not to describe this "funnel effect" more plainly?

Far be it from us to play Kremlinologist, but we're guessing that USFWS knows something we don't about wildlife mortalities at Ivanpah.