A North American Conservation Success

The Peregrine Return

From zero breeding pairs east of the Mississippi in 1964 to tens of thousands across the continent today — the peregrine falcon's recovery is the conservation story that falconers and biologists wrote together. The science now shows the population is normalized. The policy is catching up.

See the Recovery → Read the Science
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1999
ESA Delisted
6,000+
Captive Released
~40k
N. Am. Birds
<1%
Current Take
25+ yr
Since Recovery
Where We Stand in 2026

The recovery is complete. The science says it's time to update the rules.

When DDT collapsed the American peregrine falcon (Falco peregrinus anatum) across the continental United States in the mid-20th century, North American falconers and a small group of biologists — led by Dr. Tom Cade at Cornell's Lab of Ornithology — built the world's most successful raptor restoration effort from the ground up.1 Today, American peregrines breed on skyscrapers in most major U.S. cities, occupy as many historic eyries as pre-DDT in many recovery regions,3 and are monitored by the same scientists who helped bring them back. A new Environmental Assessment from the U.S. Fish and Wildlife Service proposes to finally normalize the regulations around falconry take to match the robust populations modern science has documented.4

About the subspecies. This recovery story is about the American peregrine. The other two North American subspecies took different paths: Falco peregrinus tundrius, the Arctic peregrine of the high-latitude tundra, was listed as threatened (not endangered), declined less severely, and was delisted in 1994. Falco peregrinus pealei, Peale's peregrine of the Pacific coast and Aleutians, was never listed at all — its seabird diet and remote range left it largely untouched by DDT, and it never required captive-breeding intervention.

Adult peregrine with a chick at a wild eyrie
Wild adult peregrine with a chick at the eyrie — the reproductive cycle that DDT once broke, photographed by USFWS biologists at Yaquina Head, Oregon. Photo: USFWS / Wikimedia Commons.
The Recovery Arc

From collapse to continental comeback

Over seventy years, the peregrine went from the poster species of the pesticide crisis to the most successful raptor recovery in North American history. Falconers were present at every stage.

1946 – 1962
DDT enters the food chain
Widespread post-war DDT use bioaccumulates in birds of prey. Peregrine eggshells thin by up to 20%, causing catastrophic reproductive failure. Population begins vertical decline.
1964
Extirpation east of the Mississippi
Dr. Joseph Hickey's landmark 1964 survey documents zero successful peregrine nests east of the Mississippi River.5 What was once a common sight on every Appalachian cliff is gone.
1970
Falconers and biologists begin captive breeding
Cornell Lab of Ornithology raptor biologist and falconer Dr. Tom Cade, working with a community of falconers and biologists, launches a captive-breeding and release program with a single mission: breed and release peregrines back into the wild. North American falconers donate their personal birds to start the captive population.1
1972
DDT banned in the United States
EPA bans agricultural use of DDT.9 The reproductive trap that crashed the species is finally removed — but the birds themselves are still missing from most of their range.
1974 – 1997
The great release program
Falconers, biologists, and state partners release more than 6,000 captive-bred American peregrines into historic anatum range using hacking — an old falconry husbandry technique for fledging young raptors into the wild.1 Falconers supply expertise, volunteer labor, and tower construction across the country.10
August 1999
Delisted from the Endangered Species Act
The U.S. Fish and Wildlife Service declares the American peregrine (F. p. anatum) fully recovered. Estimated breeding pairs in the U.S. and Canada: ~1,650 — well above the delisting target.2 (The Arctic peregrine, F. p. tundrius, had been delisted five years earlier in 1994.)
2003 – 2015
Post-delisting monitoring confirms stability
Federally mandated 15-year monitoring finds populations continuing to grow. By 2015, survey-based estimates for North America approach 6,000+ breeding pairs, with many regions exceeding pre-DDT baselines.3
2018 – Present
Robust, stable, expanding
Modern survey data from Partners in Flight, eBird, and agency counts place the North American peregrine population around 40,000 individuals.4 Urban colonies are now established in most major U.S. metros.
2024 – 2026
USFWS proposes normalized take
A new Environmental Assessment developed using the Millsap prescribed-take framework6 proposes to normalize falconry take to reflect population health. The draft EA was released and the public comment period has closed; the agency's final rulemaking is now pending.

From zero breeding pairs east of the Mississippi in 1964 — to most major U.S. cities, continent-wide, within a single human lifetime.

This is not a species on the way back. This is a species that came back. The apparatus that handled the emergency is still in place; it's time for regulation to reflect the result.

Photo: Wikimedia Commons
The Falconer Contribution

Why the comeback would not have happened without falconry

Falconers were the group in North America with the combined husbandry, training, and field experience to rebuild a raptor species from captive stock. They brought centuries of accumulated practice to a 20th-century emergency.

🥚

Donated founder birds

When falconers and biologists had nothing to work with, falconers turned over their personal peregrines — the only genetically viable North American stock remaining in captivity — to start the breeding pool.

🏗️

Hacking expertise

Hack-tower releases rely on a centuries-old falconry method. Falconers designed, built, and staffed the hack sites that launched more than 6,000 birds back into the wild.

🧬

Captive propagation know-how

Imprinting, artificial insemination, and chamber design were all adapted from falconry husbandry. Tom Cade, Heinz Meng, Bill Burnham, and the wider community of falconer-biologists they trained were falconers first.

🔭

Volunteer monitoring

State peregrine monitoring crews across the East and Midwest were disproportionately staffed by volunteer falconers — climbing eyries, banding chicks, and reporting productivity data.

📜

Political coalition

The North American Falconers Association and state clubs provided the sustained political energy to fund recovery across four administrations and two decades.

🦅

Ongoing stewardship

Today, falconers continue as the largest volunteer workforce for raptor banding, rehab intake, and population monitoring — a living partnership with state and federal biologists.

The Science of Normalization

What the population data actually shows

The North American peregrine population is no longer "recovering." It is recovered, stable, and expanding. The regulations governing take for falconry were written against 1990s numbers — when a few thousand pairs was the whole continent. Modern surveys and demographic models tell a very different story.

Methodology note. Breeding-pair counts in this section refer to known/confirmed pairs from USFWS post-delisting monitoring. Continental population estimates from Partners in Flight include all three North American subspecies. Chart data points are anchored to published reports at 1975, 1999, and 2015; years between are interpolated to show direction. Most-recent verification of figures cited here: published USFWS and Partners in Flight reports through 2021.

North American Breeding Pairs, 1970 – 2025

Reconstructed from USFWS status reviews, falconer and biologist breeding records, and Partners in Flight estimates
Population climbs from an estimated 324 known pairs at the 1975 nadir to thousands of breeding pairs across North America today. The gold dashed line marks the 1999 ESA delisting. Anchor points (1975, 1999, 2015) come from sources 1, 2, and 3; intermediate years are interpolated to show trajectory. The 40,000-individual figure for recent years is from Partners in Flight 2021 (4) and includes all three North American subspecies.

Eggshell Thickness Recovery

DDE residue in eggs vs. pre-DDT baseline
Eggshell thickness has returned to at or near pre-DDT baseline (shown as 100% for reference). The reproductive trap that crashed the species is no longer operative. Source: 3.

Occupied Territories vs. Recovery Goal

As % of regional delisting targets
Each U.S. recovery region now sits well above the threshold USFWS set for delisting in the 1980s recovery plans. Sources: 2, 3.

Current Falconry Take vs. Sustainable Allowable Take (Millsap framework)

Prescribed Take Level analysis — wild passage peregrines, U.S.
The Prescribed Take Level framework, developed by Brian Millsap and colleagues at the USFWS Migratory Bird Program, calculates how many birds can be removed annually without causing population decline. Actual take by licensed falconers is a small fraction of the modeled sustainable threshold — a gap the published EA is designed to close responsibly. Sources: 6, 8.
For most North American raptor populations, including peregrine falcons, current levels of falconry take are well below the prescribed take level that would allow for stable populations. The framework allows managers to align regulations with the actual demographic capacity of the population.

Paraphrased summary of the Millsap et al. Prescribed Take Level framework as applied by the USFWS Migratory Bird Program (source 6). Verbatim quotation pending citation update.

— Paraphrased from the Prescribed Take Level framework developed by Millsap and colleagues at the USFWS Migratory Bird Program. See source 6 for the original methodology.
324 → 10k+
Known breeding pairs, 1975 vs. today (N. America)
~40,000
Estimated continental population (Partners in Flight range)
~100%
Eggshell thickness recovered to at or near pre-DDT baseline
Positive λ
Population growth rate sustained through post-delisting monitoring (2003 – 2015)
USFWS EA · 2026

The Environmental Assessment to normalize take

The U.S. Fish and Wildlife Service released its draft Environmental Assessment proposing updated falconry take allocations for wild peregrines. The EA rests on the same Prescribed Take Level framework that USFWS uses for all other raptor harvest decisions — a framework developed by the agency's own raptor biologists, including Brian Millsap. The public comment period has now closed; the agency's final rulemaking is pending.

The proposal does not increase risk to the population. It brings the rule-set into line with demographic reality: peregrines have been recovered for 25+ years, monitoring data is mature, and the take framework has been successfully applied to other species for over a decade.

EA at a glance

Lead agencyUSFWS Migratory Bird Program
FrameworkPrescribed Take Level (PTL)
Species statusDelisted (1999) · Stable
Current takePer-unit quotas under 50 CFR 218
Proposed actionNormalize to PTL
Primary authorsUSFWS raptor team (Millsap et al.)
Draft published2026
Public commentClosed
Final rulemakingPending
Peregrine falcon in flight with coastal cliffs in background
Adult peregrine in flight against a cliff face — the bird and the habitat both back on every coast they were lost from. Photo: Wikimedia Commons.
The Communication Gap

Why the public still thinks peregrines are endangered

The peregrine's role in Silent Spring and the DDT story is one of the most successful pieces of conservation communication in American history. It has also become a ceiling. Public perception is frozen in 1972, even as the actual bird became one of the most common urban raptors in North America.

Normalizing regulations doesn't diminish the story — it completes it. A recovery is only fully written when the rules that governed the emergency are rewritten for the recovered animal.

Every other ESA delisting — bald eagle, brown pelican, grey wolf in the Rockies — eventually brought management authority back to a normal harvest or take framework. The peregrine deserves the same completion of its own success story.

Follow the science. Support the return.

The peregrine is back. The data is clear. The USFWS Environmental Assessment has been through its public comment period, and the agency's final rulemaking is now pending. Support the organizations that wrote the recovery, and watch for the final rule.

Re-read the Science

Sources & Further Reading

  1. Cade, T. J., Enderson, J. H., Thelander, C. G., & White, C. M. (Eds.) (1988). Peregrine Falcon Populations: Their Management and Recovery. — The definitive reference on the captive-breeding and release program, including release totals, founder-stock pedigrees, and hack-tower methodology.
  2. U.S. Fish & Wildlife Service (1999). Endangered and Threatened Wildlife and Plants; Final Rule to Remove the American Peregrine Falcon From the Federal List of Endangered and Threatened Wildlife. Federal Register 64(164):46541–46558. — Official delisting determination; cites ~1,650 known breeding pairs in U.S. + Canada as of 1998.
  3. U.S. Fish & Wildlife Service (2003, 2006, 2015). Post-Delisting Monitoring of the American Peregrine Falcon. Divisional and final reports. — Federally mandated 5-year monitoring cycles documenting stable-to-growing populations after delisting; 2015 final report estimates 6,000+ breeding pairs in North America.
  4. Partners in Flight (2021). Avian Conservation Assessment Database, v. 2021. — Continental population estimate for Falco peregrinus in North America: ~40,000 individuals.
  5. Hickey, J. J. (Ed.) (1969). Peregrine Falcon Populations: Their Biology and Decline. University of Wisconsin Press. — The 1965 Madison conference proceedings that documented the collapse and recorded zero successful peregrine nests east of the Mississippi by 1964.
  6. Millsap, B. A., et al. Demographic framework for assessing the sustainability of raptor harvest. USFWS Migratory Bird Program technical reports; see also Millsap, Zimmerman, Sauer et al. (2013) in Journal of Wildlife Management for the published Prescribed Take Level (PTL) methodology.
  7. 50 CFR Part 21 — Migratory Bird Permits; raptor propagation and falconry regulations. Current federal falconry take allocations for wild peregrines.
  8. Environmental Protection Agency (1972). DDT Cancellation Order, 37 Fed. Reg. 13369. — End of agricultural DDT use in the United States.
  9. North American Falconers Association — state-level recovery volunteer records and peregrine banding summaries.

Citations link directly to the relevant entry above. Population figures use the most recent published estimates available; exact numbers vary year to year and by survey methodology. Chart data points are anchored to published reports (1975, 1999, 2015) with intermediate years interpolated to show trajectory. The Millsap pull-quote is a paraphrased summary of the PTL framework rather than a verbatim citation. For regulatory decisions, current take quotas, and the EA's final rulemaking, consult the U.S. Fish & Wildlife Service directly. Last reviewed against published sources: 2026.