Audubon Christmas Bird Count issue: Eagles did not prosper during the ‘time of DDT’

August 26, 2015

Still photo captured from the film, “Christmas Bird Count,” by Chan Robbins; photo shows a group counting birds, probably in the 1940s or 1950s. Audubon’s Christmas Bird Count got its start in 1900.
Still photo captured from the film, “Christmas Bird Count,” by Chan Robbins; photo shows a group counting birds, probably in the 1940s or 1950s. Audubon’s Christmas Bird Count got its start in 1900.

In the notoriously wrong and misleading “100 things you should know about DDT” posted by pro-DDT, anti-wildlife Steven Milloy of “Competitive Enterprise Institute” and Fox News fame, based on the foggy rant of Dr. Gordon Edwards, we get these two misleading claims:

69. After 15 years of heavy and widespread usage of DDT, Audubon Society ornithologists counted 25 percent more eagles per observer in 1960 than during the pre-DDT 1941 bird census. [Marvin, PH. 1964 Birds on the rise. Bull Entomol Soc Amer 10(3):184-186; Wurster, CF. 1969 Congressional Record S4599, May 5, 1969; Anon. 1942. The 42nd Annual Christmas Bird Census. Audubon Magazine 44:1-75 (Jan/Feb 1942; Cruickshank, AD (Editor). 1961. The 61st Annual Christmas Bird Census. Audubon Field Notes 15(2):84-300; White-Stevens, R.. 1972. Statistical analyses of Audubon Christmas Bird censuses. Letter to New York Times, August 15, 1972]

99. The Audubon Society’s annual bird census in 1960 reported that at least 26 kinds of birds became more numerous during 1941 – 1960. [See Anon. 1942. The 42nd annual Christmas bird census.” Audubon Magazine 44;1-75 (Jan/Feb 1942), and Cruicjshank, AD (editor) 1961. The 61st annual Christmas bird census. Audubon Field Notes 15(2); 84-300]

100. Statistical analysis of the Audubon data bore out the perceived increases. [White-Stevens, R. 1972. Statistical analyses of Audubon Christmas bird censuses. Letter to New York Times, August 15, 1972]

Those claims are false with regard to bald eagles.

The careful citations offered by Milloy and Edwards simply do not exist; if the source exists, the source does not say what is claimed by these guys.  (Don’t take my word for it; go see for yourself.)

Audubon never suggested, in any forum, that their famous Christmas Bird Count had shown increases in eagles. Most other species showed no increases, either. I spent a couple of days at the library of Southern Methodist University reviewing every issue of Audubon Magazine from 1941 through 1974, and found not a single article suggesting anything other than declining eagle populations in the lower 48 states (Alaska eagles were not untouched by DDT, but were not so seriously affected; and as you will see below, the first counts of Alaska’s eagles did not occur until after 1950, so the addition of numbers from Alaska counts do not indicate an increase in U.S. population of eagles.)

I also reviewed each bird count, usually published in a separate booklet with the March issue of Audubon in that time. While raw numbers increased, that was clearly due to increases in people observing. At no point did any ornithologist or Audubon member suggest eagles were in recovery, from 1941 through 1972.

That’s a long explanation, unsuitable for quick discussion on blogs, and wholly too much for a 140-character Tweet. My experience with Milloy and his followers is that they will say my analysis somehow errs, though they cannot offer any real analysis from any other source that isn’t just a misreading of the raw bird count.

I wrote the Audubon Society, and asked them to respond to the claim. At first the press office thought the claims so bizarre that they didn’t think a reply necessary.  I sent them a half-dozen links to other documents that cited Milloy and Edwards.  Delta Willis at Audubon took the claims to officials of the bird count.

Geoff LeBaron, Director of Audubon’s Christmas Bird Count sent the following reply (posted without correction).

See also the footnote from Audubon Chief Scientist Gary Langham appended to the end of the e-mail.

LeBaron, Geoff

Sent: Friday, May 10, 2013 10:21 AM

To: Willis, Delta; Langham, Gary; Dale, Kathy

Subject: RE: DDT and effects on birds, and Audubon Christmas bird count

Hello Delta,

From the 1930s through 1970s there was a tremendous growth in the number of Christmas Bird Counts, from 203 total counts in the 30th CBC to 1320 counts in 80th CBC.  The number of observers on those counts rose from 679 in 30th to 32,322 in the 80th Count.  That is a tremendous increase in effort as well as geographic coverage, and more people in more areas are going to count more Bald Eagles, even if the populations are [were] declining.

A second major factor is that during that period many CBCs were started with the specific goal of censusing wintering Bald Eagles.  Thus we were targeting the areas where eagles were wintering, and thus tallying a much greater percentage of the total population.

Thirdly, there were only two individual CBCs conducted in Alaska prior to the late 1950s.  Bald Eagle populations never suffered dramatically in Alaska [from DDT?], and their numbers were always much higher there.  Since the late 1950s there has been a tremendous growth in the number of counts in Alaska—again, with some of these counts targeting areas where wintering eagles congregate even in the thousands.  These counts added in Alaska can contribute greatly to the total number of Bald Eagles in each season’s CBC.

Thus even while Bald Eagle populations were plummeting in the lower 48 states (outside of Florida) CBC [Citizen Science] efforts were greatly increasing, and in fact targeting monitoring Bald Eagles.  That is why both the raw number of eagles and the numbers when weighted for observer effort went up when you pull CBC data for Bald Eagle during the decades of heavy DDT use.

It’s still educational to look at raptor numbers in CBC data in the years following the banning of the use of DDT in the US.  Many species of raptors show a rapid rebound in numbers after the mid-1970s…and Bald Eagles also dramatically increased.

Per Dr. Gary Langham, Audubon Chief Scientist:   Audubon scientists are careful to include levels of participation and geographic coverage in all analyses. Fortunately, we have tracked both of these aspects since the CBC was started and so it is straightforward to adjust for their impacts.

Bird counts do not show that eagles were out of trouble during DDT years, roughly 1946 through 1972; especially they do not show that bald eagle populations increased.


Explanation of the Christmas Bird Count in four minutes, by Chan Robbins.

Chandler Robbins, founder of the Audubon Christimas Bird Count, screen capture from Audubon film
Chandler Robbins, founder of the Audubon Christimas Bird Count, screen capture from Audubon film “Christmas Bird Count.”

Nota bene: Yes, this has sat in my “to be published” box for too long. It was scheduled for publication, but it appears I had not hit the “publish at scheduled time” button. My apologies to readers, and especially to Audubon’s scientists and press people.

Spreading the news: Environmental Health News says we can learn from saving eagles, to save honeybees now

July 5, 2015

Environmental Health News invites repostings of this story, with attribution and links back to EHN’s original story.

It’s a good article. Can’t improve on it much, so let’s save time and pass it directly.

Can we learn from the success in saving the bald eagle from extinction, to save our domestic bee industry and native American pollinators?

Unintended consequences

How a law that failed to protect eagles could offer a lesson to save honeybees

June 6, 2015

By Peter Dykstra
Environmental Health News

Spraying DDT on a beach

Historic photo from EPA

The Bald Eagle Protection Act, signed into law 75 years ago on June 8, 1940, was well-intended. A multi-pronged assault on the raptors was taking its toll — habitat loss, lead-shot poisoning, and bounty-hunting by ranchers and fishermen all contributed to a growing threat. (Click here to see how this played out in Alaska.)

Congress passed, and President Franklin D. Roosevelt signed, the act to outlaw the “taking” of eagles and their eggs, disruption of their nests, or sale or possession of eagle feathers or parts.

It didn’t work. Bald eagle populations accelerated their decline, for reasons that Congress, wildlife officials, and FDR couldn’t possibly anticipate.

Throughout the late 1930’s Swiss chemist Paul Müller labored to find the right mix of synthetic chemicals to control moths. Not only did dichlorodiphenyltrichloroethane do the trick, but Müller’s lab work found it was effective against lice, houseflies, beetles, and the dreaded mosquito. Müller’s employers, J.R. Geigy AG, applied for the first DDT permit about two months before the Eagle Act passed.

Pest Management Professional Hall of Fame

Swiss chemist Paul Muller, of A. G. Geigy corporation; the man who discovered DDT kills.  Pest Management Professional Hall of Fame

The rest is natural and human history. Cheap to produce and an effective defense against lice-borne typhus and mosquito-borne malaria, DDT quickly became a fixture in farm fields, living rooms, and World War II battle theaters. Müller became a science rock star, garnering a Nobel in 1948 and — wait for it — membership in the Pest Management Professional Hall of Fame in 2004.

But bald eagles continued to decline. So did hummingbirds, robins, ospreys, pelicans and peregrine falcons. Years of science, met with serious blowback from the chemical industry, eventually proved that DDT was thinning birds’ eggshells, not to mention causing impacts in fish, humans, and other mammals. Rachel Carson’s Silent Spring drew international attention to the threat, and in the U.S., DDT was outlawed on the last day of 1972. Bald eagles, ospreys, brown pelicans and peregrine falcons have all since staged remarkable comebacks from the Endangered Species list.

Which brings us to today’s threat to other ecologically priceless wildlife — pollinators. Honeybee populations have been in freefall for more than a decade. Like the threats to eagles, the potential causes are multiple: loss of habitat and native plants, parasites, and a mix of insecticides and fungicides. Newest, and most notable among the suspects, are neonicotinoid pesticides. Like DDT, neonics were developed in the 1980’s and 1990’s and welcomed as a step forward, since they were thought to be effective on insect pests but relatively benign on non-target wildlife and ecosystems. Today they are a billion-dollar agricultural product, ubiquitous on common crops like corn and soybeans.

But mounting evidence shows that neonicotinoids may be part of the frontal assault on bees and other pollinators. In 2013, the European Union banned the use of three of the most contentious types of neonicotinoids, citing a clear and immediate risk.

In 2014, President Obama ordered the creation of a federal pollinator strategy. Its first draft came out last month, calling for everything from creating bee-friendly habitat to further study on neonics and other agricultural chemicals. The first edition of the strategy, issued in May, outlines a multi-year process for re-examining use of neonics.

If the EPA and other federal agencies concur with other studies on the potential harm of neonicotinoids, the U.S. will issue assessments for neonics in 2016 and 2017, and may or may not take action until 2018 to 2020. All of this will take place under a new president who may or may not take interest in protecting bees.

That timetable may work. Or not. Or, with a president with little more than a year left in office and a hostile Congress, it may be a moot point.

But perhaps a more important point is that in 1940, the President and Congress took action on the known threats to eagles. They didn’t know about the chemical risk from DDT. If neonics are as big a threat as the science suggests, the current president and Congress won’t have ignorance as an excuse for waiting.

EHN welcomes republication of our stories, but we require that publications include the author’s name and Environmental Health News at the top of the piece, along with a link back to EHN’s version.

For questions or feedback about this piece, contact Brian Bienkowski at

Prior to the 20th century, all eagles, including bald eagles were regarded as pest predators and pest carrion eaters.  Populations of the birds plunged between 1492 and 1900.  The first eagle protection law in 1918 did little to stop the decline in eagle populations.  A harder-toothed anti-hunting law in 1941 helped, as discussed above. Anti-environmentalists often seize on these historic facts to claim that DDT was not to blame for the failure of the eagles to recover after 1941.  But recovery of the birds started as soon as DDT was banned.  Fecundity of bald eagle populations rose in direct proportion to the drop in residual DDT and DDT breakdown products in the flesh and fat of eagles.

In Silent Spring Rachel Carson provided 53 pages of notes and citations to science journals, documenting the dangers and the unknowns of DDT and a variety of other chemicals. The book was published in 1962.  It is a tribute to Carson’s meticulous research that every study she pulled from is still accurate today. Later research only supported her conclusions, or in the case of bird damage and eggshell thinning, provided documentation of even more and greater harms.

Do we learn from history?

Gresham’s Law: DDT disinformation crowds out facts

February 18, 2008

I love irony.

Henry VIII devised a novel way to save money. He ordered coins be minted containing silver, as during the reign of Henry VII, but he ordered that the purity of the silver be reduced. Edward VI continued the policy so that, by the time of the rule of Queen Elizabeth I, royal advisor and financier Sir Thomas Gresham observed that most of the old, high-silver content coins were out of circulation, hoarded by people against future inflation, allowing the lesser-valued money to circulate. Gresham told Elizabeth the bad money drove out the good money.

Sir Thomas Gresham (c. 1519 – 21 November 1579), British financier and advisor to Queen Elizabeth I and earlier regents. Portrait c. 1554 by Anthonis Mor

Sir Thomas Gresham (c. 1519 – 21 November 1579), British financier and advisor to Queen Elizabeth I and earlier regents. Portrait c. 1554 by Anthonis Mor.

The principle had been observed earlier by Aristophanes and others. It is known in modern economics as Gresham’s Law, since 1858 when British economist Henry Dunning McLeod decided to honor Gresham by naming the rule after him.

The bad drives out the good, the cheap drives out the more expensive, gossip drives out good information — the principle is widely observed in areas beyond economics.

And so it is that with regard to DDT, the good information about the dangers of DDT and the benefits of restricting use of the chemical has been driven out of the marketplace by bad information claiming DDT is safe, and ignoring the significant benefits reaped when massive use of DDT was stopped.

And here’s the irony: DDT-happy critics of good environmental policy now claim to be the good information driven out by the “bad” information of DDT’s harms. No kidding. A columnist named Natalie Sirkin, in a column delivering almost nothing but bad, vile information, says bad information drives out the good, never once noting the irony.

The defense of DDT was, from the beginning, a lost cause. A few of us vainly hoped that science would prevail. We soon found that Gresham ’s Law, which states that bad currency drives out good currency, applies to science as well as to economics.

No kidding it applies. Do a Google search for “DDT” today and you’ll find all over the internet the disinformation of Gordon Edwards’ ghost and junk science purveyor Steven Milloy. You will have a difficult time finding any solid study showing how DDT nearly killed off the American bald eagle, however, and you’ll have to do a targeted search to learn of any dangers of DDT — information on human toxicity is almost impossible to find, though it’s easy to find many recountings of Gordon Edwards’ bold drinking of a teaspoon of DDT before lectures.

(Natalie and Gerald Sirkin write for the American Spectator; at this writing, Google features warnings on all of their material at the time of this writing, saying the site host may try to insert “malicious software” on your computer — so I have not linked there. This problem should sort itself out, I hope.)

(The Environmental Protection Agency (EPA) works to get a history of the agency up on the ‘net; a lot from the DDT ban era is now available at the EPA site for scholars; Milloy will not be happy to have factual rebuttal officially and easily available.)

Below the fold, I’ll offer a point-by-point rebuttal of the bizarre claims in favor of DDT and against the noble public officials who worked to restrict its use.

Read the rest of this entry »

Eagle recovery still on, since DDT halt

December 26, 2007

One-paragraph in a story in the Philadelphia Daily Inquirer with a lot of impact:

A record number of bald eagles soared past Hawk Mountain in Berks County this fall, continuing a comeback that began with the banning of DDT in 1972. Then, 18 eagles were counted during the typical migration. The count this fall: 230. – Don Sapatkin

Caption from blog: Visitors and staff gather on the South Lookout at Hawk Mountain Sanctuary, near Kempton, Berks County. (HAWK MOUNTAIN SANCTUARY PHOTO)

Caption from blog: Visitors and staff gather on the South Lookout at Hawk Mountain Sanctuary, near Kempton, Berks County. (HAWK MOUNTAIN SANCTUARY PHOTO) (Photo substituted here for previous photo noted below, which has gone missing in DatedLinksLand)

 South Lookout at Hawk Mountain, Pennsylvania

South Lookout at Hawk MountainThe view from a rocky ledge near the entrance at Hawk Mountain provides a spectacular view of the countryside and is a good vantage point for watching migrating raptors in the fall. This photo was taken the afternoon of 10-16-2006.  Public domain photo, via

The white area at upper center is the “River of Rocks”. According to, this formation is a mile-long boulder field, up to 40 feet deep, which was deposited 10,000-12,000 years ago (the end of the last Ice Age), when glaciers stopped 40-50 miles to the north of this location. Repeated freezing and thawing cracked boulders from the ridgetop that gradually slid to their current position.

Spreading miasma on malaria

July 23, 2007

The Straight Dope has a motto: “Fighting ignorance since 1973. (It’s taking longer than we thought.)”

Alas, the motto could work as well for people who understand science, who understand chemistry and biology, and who urge sanity in discussions about DDT, malaria prevention and control, and Rachel Carson.

Photo from a 1950s science text, showing DDT spraying on crowded beach

DDT sprayed on a crowded beach -- photo from an unidentified 1950s publication. Caption in the photo: "This machine is spreading a kind of fog of DDT spray to see if it will kill the mosquitoes and other insects on the beach. Outdoors, the spray soon spreads and does not harm people."

The meme that “Rachel Carson caused millions of deaths” and prompted the disappearance of DDT is factually in error, but popular, and still spreading. It doesn’t help that there are well-funded groups that work hard to spread the disinformation.

As Ben Franklin noted, in a fair fight, truth wins. The difficulty is that the fight for truth about DDT and Rachel Carson has never been fair, and the anti-sense forces have a 25-year head start on wise people like Bug Girl, Deltoid, Rep. Jason Altmire of Pennsylvania, and even dunderheads like me.

How widespread is the damage? Well, how many editorial pieces were there slamming Rachel Carson, falsely, on the event of the 100th anniversary of her birth? Has Sen. Tom Coburn, R-Okla., lifted his holds on naming a post office for her?

The damage continues to spread.

For example, these blogs have fallen victim to the malaria/DDT/Rachel Carson hoax:

a. London Fog, ostensibly about government in London, Ontario, goes off half-cocked on DDT

b. Irrational Optimism, about a Georgian transplanted to Utah, picks up the misunderstandings of DDT

c. The Squamata Report, a general diatribe, accepts at face value all the falsehoods about DDT, especially those that cast scientists and environmentally-concerned politicians in a light where they can be ridiculed

d. — not the most bizarre view there, so of course it also accepts the false myths as good data

e. Boots and Sabers, sort of a frat party for young military guys, makes the gung-ho gonzo claim that it would have been worth it to sacrifice bald eagles because DDT could have saved African kids

d. Even Forbes Magazine’s blogs put out the faulty version of the story

e. Red State includes an artless and caustic piece here (repeated during what appears to be a brain power failure at PowerLine)

f. The famous column at the Wall Street Journal, marking a premature end of fact checking at that newspaper’s opinion columns

g. “Rachel Carson’s Genocide,” hysteria at a Ron Paul site misnamed Rational Review

h. Even Nobel Prize winning economists and distinguished federal judges get sucked into the vortex of specious information if they are not scrupulously careful — as Becker and Posner did here, and again here. (See final installment,too.)

And even while fighting ignorance and generally rebutting the wild claims about Rachel Carson, even Cecil Adams at Straight Dope gets suckered in by some of the myths. (In “moderate amounts,” DDT concentrates up to 10 million times in the wild, poisoning birds of prey and predator fishes, especially; DDT is deadly to mosquito-eating birds and bats, and pest-eating lizards; EPA’s hearings on DDT were overwhelmingly in favor of banning the substance — a court suit cited EPA for not moving fast enough to ban such a dangerous substance, and evidence in such trials is not made up; the cause of egg-shell thinning in birds is pretty solidly established to be DDT and its breakdown substances, only the exact process is not well understood; the international treaty against POPs has a specific out-clause for DDT to be used to prevent malaria; and so on).

So, there’s a lot of work to be done, and little time. Stay tuned.

Update: The Capital Times in Madison, Wisconsin, had a wonderful feature on the 1970 hearings in that state to ban DDT,[alternate URL here] and the subsequent success with the spectacular return of the bald eagle to local waterways. In comments, early in the process, the junk science about DDT and malaria appear. It’s everywhere.

P.S. — Here’s a reading for a lecture at Purdue University that neatly summarizes Carson’s life and work, accurately. (In fact, the entire lecture series, by Jules Janick, should prove interesting to people interested in horticulture.)

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