The Mojave Desert is a harsh land, an arid expanse where only the hardiest creatures can survive. But what happens when one species, for its own comfort, alters the landscape in ways that favor another? What happens to other species in this shifted circumstance? We are witnessing just such a shift. Humans love surface water, shady trees and buildings. They strive for rapid transportation, both of themselves and the energy they use to power their civilization. They grow crops and need places to stow the waste they generate.
In the last 80 years or so, ever since the end of World War 2, humans have flooded across the Mojave: building roads, planting alfalfa and pistachios, building suburbs and more and more roads to connect them. They’ve strung high-tension electrical lines from thousands of giant towers. They’ve established artificial lakes and golf courses and parks. In the process they have, without intending to, transformed the Mojave from a place largely hostile to Common Ravens to a paradise for the resourceful birds. Food is plentiful for ravens: lots of dumpsters to dive in, discarded French fries at highway rest stops, pet food unattended in back yards, a daily harvest of road-killed animals to pluck off the pavement. Free water is easily available at sewage ponds, golf course water hazards, in ag fields. Power towers provide ideal nesting structures and planted trees provide cool shade in the midday heat of July. Ravens have responded, as wild animals do to expanded opportunities, by having lots and lots of babies. And with plenty of food and water to support them, those babies have survived in high numbers. Ravens are doing very well by us and their numbers grow year by year.
Enter the desert tortoise, a quiet and careful animal, a denizen of the Mojave for ages. In a desert largely free of ravens the tortoise did fine in this harsh landscape, by using available resources very carefully. Tortoises don’t do well around humans and their babies are a favored food of ravens. The problem for tortoises is that it takes 7 to 10 years to grow from a hatching size of about an inch-and-a-half to about 5’ long. This crucial period in a tortoise’s life, when its shell is still too thin to resist the hammering of a raven’s beak, that is the gauntlet that every tortoise must run.