Habitats change over time: flowers bloom, turn to fruit, and then die; leaves go from green to brown; bare patches of ground made by gophers get covered in grasses; pools once teeming with plants dry up; wildfires periodically turn lush grasslands in to dust. How do animals deal with this constant change of resources? What did our human ancestors do? They move! Temporary habitats, or ephemeral habitats, are very common in the natural world and the adaptations of animals to move from one temporary resource to another are also common.
This is common in my own work, as the Ohlone tiger beetles move from one bare ground area to another. The bare ground changes location because the disturbance from burrowing animals, like gophers, changes locations too. Also, some bike trails are used more one year to the next. This keeps the tiger beetle habitat dynamic, and helps keep the Ohlone tiger beetle population alive and well.
For the tiger beetles, this happens within one habitat area; on a larger scale, some animals completely die out in a habitat and have to move on to a whole new place. You can think of it like a series of dots on paper disappearing in one spot only to reappear in another. This is a natural phenomenon, but humans are changing it. In many cases, human activity and construction have destroyed areas in which the “dots” can reappear, causing them to disappear forever. BUT, sometimes we can CREATE new areas in which the dots can reappear, making new refuges and resources for animals in search of habitat.
Just as we can scrape the ground to make bare ground for tiger beetles and bulldozers can create new areas of butterfly habitat, Dolny and Harabis found that underground mining can create havens for dragonflies. In the Silesian Industrial Region of Poland and the Czech Republic, coal mining abounds and causes the ground to sink- as much as 100 feet!- creating a bowl-like area. This depressed ground becomes pools as it fills with groundwater. Dolny and Harabis surveyed the dragonflies in the area, comparing the mine pools to natural ponds. They found that not only did the mine pools have 50 out of 54 species present, they also had lots of rare dragonflies! In some cases, the mine pools provide the only habitat for dragonflies whose bog habitat has been completely degraded. The authors rightly talk about how we can use areas like this for species conservation, viewing them as potential instead of with despair.