“The search for rare butterflies in the high mountains is not really a science, nor does it require too much technical mountaineering skill, and although is has many elements of both, it is mostly a path of extreme patience, more akin to the metaphysical aspects of meditation, than to anything else”. —John Hessler, Searching for the Rarest of Butterflies in the Alps (2024)

Biography

When not climbing in the Alps, looking for rare plants in the desert, or searching for endangered butterflies in some remote valley in the Pyrenees, I am an historical biogeographer, lepidopterist, and writer, living in Nice, France.

The founder of the LEP-LAB for the study of alpine lepidoptera, my field oriented biogeographic research centers on mapping the intricate population dynamics and spatial distribution patterns of rare forms of high-altitude butterflies in the Pyrenees, and in the remote valleys of the parc national du Mercantour and the parc national des Écrins.

Recently, I have begun working on reconstructing the historic distribution patterns of the critically endangered large blue butterfly, Maculinea arion, across Europe and the United Kingdom, from preserved museum specimens.

Interested in rare butterfly migrations, I am also mapping the appearances of Nymphalis antiopa across the UK and the distribution of the historically recorded periodic influx many individuals, even though none of the immature stages of this butterfly has ever been found in the wild in the British Isles.

My long-term projects include tracing the locations of the specimens and collectors, whose work is contained in the monumental Biologia Centrali-Americana, and researching the historical collecting and explorations of the naturalists, James John Joicey, Henry John Elwes, Vladimir Nabokov and William Fassnidge.

The author of twelve books and more than two hundred articles, including the New York Times bestseller, MAP: Exploring the World, my latest article, To save lives: Lessons of a pandemic cartographer, was published in the Transactions of the Institute of British Geographers, in late 2024.

A Fellow of the Royal Geographical Society (FRGS), I find pondering the mysteries contained in ancient DNA, wondering about the fate of Colias ponteni, and marveling at the complexity and beauty to be found in Darwin’s tangled bank, strangely comforting.