Nevada Solar Farm Killing Birds: Crescent Dunes and Why No Fines

The solar facility most often described as a Nevada bird-killer is the Ivanpah Solar Electric Generating System, which sits just across the state line in California’s Mojave Desert, about five miles from Primm, Nevada, and is clearly visible from Interstate 15.¹ A second concentrated solar power tower, Crescent Dunes near Tonopah, is actually inside Nevada and had its own high-profile bird kill in 2015. Estimates of annual bird deaths at Ivanpah range from about 1,000 to as high as 28,000 depending on who is counting, with federal biologists landing near 6,000.² Neither plant has ever been fined, and Ivanpah will keep running until at least 2039 after California regulators rejected a proposal in December 2025 to shut it down.

Why These Plants Burn Birds Out of the Sky

Ivanpah and Crescent Dunes use concentrated solar power, or CSP, which is a different technology from the photovoltaic panels most people picture when they think of solar. More than 170,000 software-controlled mirrors called heliostats aim sunlight at boiler towers to make steam, and the air around those aim points reaches intensities high enough to singe feathers. Birds that fly through these zones of concentrated energy, known as solar flux, can suffer burns, feather damage, or fatal injuries.

During Ivanpah’s first year of monitoring, collisions with mirrors and structures accounted for roughly 52% of bird deaths with identifiable causes, and singeing accounted for about 47%. Observers at the plant describe trails of smoke when something passes through the flux as “streamers.” Early reports suggested birds were vaporized mid-flight, but analysis found that Ivanpah’s flux levels, around 600 kilowatts per square meter, are not strong enough to vaporize a bird. Most singed birds fall as recognizable carcasses. Many of the streamers people see are actually insects, which incinerate at rates of 400 to 500 per hour.³

Those burning insects help explain why the kill numbers stay high even with mitigation. The U.S. Fish and Wildlife Service has described a “funnel effect” in which the intense light attracts insects, which then draw in insectivorous birds and the raptors that hunt them, turning the facility into what one agency document called a potential “population sink.”⁴ Warblers, hummingbirds, and nighthawks are among the most commonly recovered carcasses.⁵ Roadrunners frequently get trapped along the perimeter fence, where coyotes finish them off.²

The Fight Over How Many Birds Die

Nobody agrees on the Ivanpah death toll, and the gap between estimates spans an order of magnitude. During the first year of monitoring, from October 2013 to October 2014, surveyors recovered 703 bird carcasses, which translated to roughly 3,500 estimated deaths after adjusting for scavenger removal and search coverage limits.³ Federal biologists have pegged the annual figure at about 6,000.² BrightSource Energy, a co-owner, has cited a number closer to 1,000.⁵

The 28,000 figure that gets quoted in news stories comes from ecologist K. Shawn Smallwood, who testified on behalf of the Center for Biological Diversity. Smallwood took the 183 dead birds found in April and May 2014, assumed that scavengers took four of every five carcasses before counters could reach them, and then multiplied again by five on the assumption that only about a fifth of the heliostat fields were being systematically searched. That produced an estimate of about 2,365 deaths per month, or roughly 28,380 per year.⁵ Smallwood himself called the math “back-of-the-napkin” and based on unverified assumptions. BrightSource called the figure “science fiction” and pointed to 321 documented deaths over six months as a more accurate accounting.⁶

Both sides have a point about the other’s weaknesses. Smallwood’s multipliers stack large assumptions on top of each other. BrightSource’s raw counts almost certainly undercount reality because they cannot capture scavenged or undetected birds. An independent analysis cited by E&E News estimated about 5,000 deaths after adjusting a raw tally of 1,098 recovered carcasses in one year for detection and scavenging rates.⁷

Crescent Dunes: The Plant Actually in Nevada

Crescent Dunes, near Tonopah, was the first utility-scale CSP plant in the United States to use molten-salt energy storage. On January 14, 2015, during a testing phase, biologists watched roughly 130 birds die in about six hours after flying into concentrated solar flux about 1,200 feet above the ground. Some birds, including common ravens, were reportedly incinerated so thoroughly that no carcass could be recovered.⁸

After that incident, SolarReserve reprogrammed the heliostats to spread their standby aim points over a much wider area, which dropped peak flux below the threshold known to damage feathers. The company reported only one bird fatality during the 30 days of commissioning that followed, and its CEO said the facility recorded just six dead birds between January and October 2015 after the fix.⁹ Crescent Dunes had chronic financial troubles beyond its bird issues. Tonopah Solar Energy LLC, the project owner, filed for Chapter 11 bankruptcy in January 2026, its second filing since 2020, and was seeking to sell the facility’s assets.¹⁰

Why No One Has Been Fined

No federal or state agency has ever fined Ivanpah for killing birds. The California Energy Commission has said it is not aware of any formal enforcement actions by the U.S. Fish and Wildlife Service or the California Department of Fish and Wildlife over avian mortality at the facility.¹¹ A 2016 congressional review by the House Natural Resources Committee found no instances in which the Department of the Interior had pursued enforcement actions against any solar operator for bird deaths.¹²

The Migratory Bird Treaty Act makes it illegal to kill migratory birds and carries penalties of up to $15,000 per bird and six months in prison.¹² Enforcement, though, has historically depended on prosecutorial discretion. The Fish and Wildlife Service generally pursues cases only where a company has neglected reasonable mitigation, and FWS officials have reportedly praised Ivanpah’s efforts to reduce bird deaths.¹³

The legal standard shifted in 2017 when the Department of the Interior reinterpreted the MBTA as applying only to intentional killings, which effectively exempted incidental deaths from industrial operations. The Biden administration reversed that position in December 2021 and returned to treating incidental take as prohibited. In practice, FWS has kept relying on enforcement discretion rather than fining solar operators. No incidental take permit framework exists specifically for solar projects, though USFWS has said it intends to develop one.¹⁴

Operators have deployed software fixes that spread heliostat aim points in standby mode, switched to LED lighting that is less attractive to insects, installed anti-perching spikes, used sonic predator-call systems, and sprayed a grape juice extract vapor from a device called the BirdBuffer that is designed to irritate birds.¹³ Evidence of how well any of this works at Ivanpah has been slow to arrive.

Why Ivanpah Is Still Running

Ivanpah’s owners, together with Pacific Gas & Electric, tried to terminate the plant’s power purchase agreements and shut it down, citing underperformance and high costs. The plant has consistently produced only 70% to 80% of its projected annual output since 2014.¹⁵ Both the Biden and Trump administrations supported closing it, and the Department of Energy backed the contract termination.¹⁶

California disagreed. On December 10, 2025, the California Public Utilities Commission unanimously rejected PG&E’s termination agreements, citing rising electricity demand from data centers and artificial intelligence and the risk of stranding more than $333 million in grid infrastructure that ratepayers had already funded.¹⁷ The existing power purchase agreements run through 2039, so the decision effectively keeps the plant operating for at least another 13 years. The CPUC rejected the termination “without prejudice,” which leaves room for redevelopment proposals, including a plan from former National Renewable Energy Laboratory researchers to retrofit the plant with molten-salt thermal storage.¹⁵ For now, the mirrors still track the sun and the bird problem remains unresolved.

How the Numbers Compare to Other Bird Killers

The deaths at CSP plants are real, and they look different in the broader picture of what kills birds in the United States. A 2016 study estimated that all forms of solar energy production kill between 37,800 and 138,600 birds a year nationwide. Fossil fuel power plants are estimated to kill about 14.5 million birds a year across the full cycle of extraction, generation, and pollution.¹⁸ Building collisions kill hundreds of millions a year, and domestic and feral cats kill up to 4 billion.¹⁹

Per unit of energy, Ivanpah’s first-year rate was estimated at 0.7 to 3.5 bird deaths per gigawatt-hour. Fossil fuel plants kill about 5.18 per gigawatt-hour, and wind energy kills about 0.27.³ Standard photovoltaic solar panels, the kind on rooftops and in most utility-scale solar farms, do not produce the solar flux that incinerates birds at power towers. A study of 10 PV facilities in California and Nevada estimated about 2.49 bird deaths per megawatt per year, well below the Ivanpah rate.²⁰ PV panels do kill some birds through collisions and through a “lake effect,” in which water-seeking birds mistake dark reflective panels for water, but the mechanism that makes Ivanpah and Crescent Dunes notorious is specific to the tower-and-mirror design.

1
California Energy Commission. Ivanpah Solar Electric Generating System
2
Los Angeles Times. Solar Plant Bird Deaths
3
U.S. Department of Energy Office of Scientific and Technical Information. Ivanpah Solar Electric Generating System Avian and Bat Monitoring Plan
4
PBS SoCal. USFWS Mysterious Funnel Effect Harming Wildlife at Solar Plant
5
PBS SoCal. Deconstructing the Dispute Over Ivanpah Bird Kill Numbers
6
Grist. The Mystery of Huge Solar Plants and Tiny Dead Birds
7
E&E News. Bird Deaths at Nev. Plant Remain a Mystery
8
PBS SoCal. Scores of Birds Killed During Test of Solar Project in Nevada
9
IEEE Spectrum. Reassessing Bird Deaths From Solar Power Towers
10
Bloomberg Law. Crescent Dunes Solar Plant Owner Seeks Asset Sale in Bankruptcy
11
Fox News. Regulators Allow Solar Plant to Kill Thousands of Birds Annually
12
House Natural Resources Committee. Hearing Memo, Oversight Hearing
13
E&E News. 3,500 Birds Died at Ivanpah Power Towers in First Year
14
Federal Register. Regulations Governing Take of Migratory Birds; Revocation of Provisions
15
SolarPACES. Solar Experts Offer a Solution in Ivanpah Decommissioning Battle
16
Los Angeles Times. Trump, Biden Both Want This California Solar Facility to Close
17
California Public Utilities Commission. Resolution E-5429
18
PolitiFact. Solar Farms Kill Thousands of Birds, Not as Many as Fossil Fuels
19
MIT Climate Portal. Do Wind Turbines Kill Birds
20
National Center for Biotechnology Information. Avian Mortality at Photovoltaic Solar Facilities