On November 5, 1950, The Field Museum [the Chicago Museum of Natural History at the time] Curator of Mammalogy Colin Sanborn received an extraordinary letter, which began as follows:
I should like to make a rather unusual request of you. Some twenty-five years ago I gave the then Field Museum several specimens from my bird collection. Included among them was a habitat group of Kirtland's Warblers, consisting of the two adults and four nestlings in the nest, mounted by Ashley Hine...I know that the Museum used to have souvenir photograph postcards of many of its mounted groups on sale to the public. Could you find out for me whether such a photo was ever made of this Kirtland's Warbler group, and if so, let me know how I can get one?
It wasn't the request itself that was so unusual: individuals (or their descendants) frequently inquired about a specimen donated to the Museum. It was the letter's author, in this case, that made it stand out: Nathan Leopold, Jr. Prior to becoming part of the infamous duo Leopold and Loeb, convicted for kidnapping and murdering Bobby Franks, a 14-year-old neighbor, Leopold had been a birder and ornithologist. Writing from prison in Joliet, Illinois, he hoped to receive a photograph of a group of specimens he'd donated as a very young man.
In addition to specimens from Loeb—The Field Museum also has a Cooper's hawk and a praying mantis—the Library owns one of only a couple of known extant copies of a booklet called Spring Migration Notes of the Chicago Area that Leopold helped compile. He was just 15 years old at the time the booklet was published.
Joshua Engel, a research assistant at The Field Museum, writes, "This little booklet has so much history, it's hard to know even where to begin. Let's start with the fact that the first author, James D. Watson, is the father of one of the most famous scientists of the 20th century, also named James D. Watson, who along with Francis Crick is credited with the discovery of the structure of DNA. But that's the least of it. The third author is even more intriguing. A budding young ornithologist, Nathan Leopold would spend the bulk of his adult life in prison for the murder of Bobby Franks, one of the most famous crimes of the 20th century."
James D. Watson the younger describes how his father met Leopold: "It was in Jackson Park in 1919 that Dad had met the extraordinarily talented but socially awkward sixteen-year-old University of Chicago student Nathan Leopold, who was equally obsessive about spotting rare birds. In June 1923, Leopold's wealthy father financed a birding expedition so Nathan and my dad could go to the jack pine barrens above Flint, Michigan, in search of the Kirtland warbler. In their pursuit of this rarest of all warblers, they were accompanied by their fellow Chicago ornithologists George Porter Lewis and Sidney Stein, and in addition by Nathan's boyhood friend Richard Loeb, whose family helped form the growing Sears, Roebuck store empire."
The Field Museum's copy of Spring Migration Notes of The Chicago Area, published in 1920, is now stored in the Mary W. Runnells Rare Book Room. Because of its historical value, it was added to the Biodiversity Heritage Library, including the type-written, hand-signed letter on page four from young Nathan Leopold to Ruthven Deane, a leading ornithologist of his time and a resident of Chicago, who eventually donated part of his collection of specimens to The Field Museum (as Leopold did when he went to jail). The cover of this copy even says "Compliments of the authors," presumably written by Leopold.
Aside from the fascinating backstory, there's the actual information that the booklet contains, a priceless indication of what the birdlife of Chicago was like in the early part of the 20th century. At the time, many wetland birds that are now rare or altogether gone as breeding birds were still common, an indication of the destruction of wetlands in the Chicago area over the last century. This includes birds like Black Tern (about which the authors say "Breeds commonly"), King Rail ("Common summer resident"), and Wilson's Phalarope ("Nests in the Calumet region").
On the other hand, grassland birds were already declining, with many formerly common birds becoming rare. For example, Greater Prairie-Chicken was "A formerly abundant permanent resident; now rather rare," Northern Bobwhite was "A formerly very common permanent resident, but now rather rare," and Loggerhead Shrike, which then was known as Migrant Shrike, was a "Fairly common summer resident." These days you have to go hundreds of miles from Chicago to find Loggerhead Shrike or a prairie-chicken. Additionally, there are spring arrival dates for every species each year from 1913 to 1920.
Colin Sanborn's reply to Leopold must have been disappointing. He writes on 20 November 1950: "Your group of Kirtland's warblers were never photographed and in fact have never been on exhibition." Sanborn goes on to write about his own activities in a breezy, newsy tone, e.g., birding, giving talks to a local ornithological society, etc. In other words, no mention of the fact that the letter he's responding to is signed by infamous prisoner #9306-D.
Leopold spent 33 years in prison until his parole in 1958. Active in the Natural History Society of Puerto Rico, Leopold traveled throughout the island for birdwatching and in 1963 he published Checklist of Birds of Puerto Rico and the Virgin Islands. He died of natural causes in Puerto Rico in 1971 at the age of 66.
As for the Kirtland warblers—happily, they are making a comeback. According to Joshua Engel, "The species has made an incredible comeback, from a low of about 200 singing males in the early 1970s to over 2000 today. It's likely to be removed from the endangered species list in the next few years."