The earliest use of the term "landscape of fear" that I could find on a quick search referred to a study about how female college students felt while walking particular routes alone after dark. Put in this context, one can well understand why people don't necessarily pick the simplest or most direct route to their objective, and why there are certain places one might simply wish to avoid altogether.
The idea, however, was soon extended to ecology, whereby the distribution of animals across a landscape is determined, not just by physical factors or the direct action of predators, but by fear. The idea is that particular prey animals might become less common in a particular area, not because predators are killing them in those areas, but because they fear that they might.
So, depending on how the predator you are most concerned about hunts, you might avoid open areas where you can easily be seen, or denser ones where they can easily hide. Puma/cougar/mountain lions, for instance, kill most of their prey near forest edges, and animals such as elk adjust their own movements accordingly. At the very least, prey animals will approach such areas cautiously, remaining vigilant, and thus spending less time feeding or resting than they might elsewhere.
While the general idea had been around for decades, it became extended to the modern biological concept of the "landscape of fear" around 2010, where perceived predation risk, as indicated by any of various measures, is plotted against the physical geography of an area. When we are studying how animals use particular habitats, we need to take fear into account just as much as the availability of useful resources.
But we can extend the concept further. The landscape in question need not be physical; it could also be temporal. Consider those college students again. They might avoid certain places, or be sure to travel in groups or with other protection if they have to (i.e. remaining vigilant), but they might also, so far as possible, just not walk the streets after dark.
This, in the technical parlance of ethology, is "diel behaviour". That is, how your activity changes throughout the day. For example, what is considered the founding study to use the landscape of fear concept showed how elk in Yellowstone Park avoid certain areas because they are afraid of wolves. The assumption was that the elk just found those areas scary, as well they might, and so stayed away from them. But it turns out that elk are quite happy to forage for food in places frequented by wolves if they think that the wolves are asleep.
The landscape of fear can therefore be said to change, not just slowly as habitats change with rivers drying up or whatever, but from hour to hour throughout the day. There are places you might be happy to visit during the day that you wouldn't want to go at night.
Perhaps the clearest example of this comes not from fear of predation, but fear of humans. Even where wild animals are not at direct risk of being hunted by humans, they tend to avoid us, and that's just as much a landscape of fear as anything caused by regular predators. The details can be complex, but a common trend is that animals that have to live near humans become more nocturnal.
That's the opposite of what we would usually do if we found a particular place threatening, but that's rather the point. Humans are mostly active during the day, so if you want to avoid them, then, so far as you possibly can, it is better to be active at night. This is something seen across a wide range of animal species, although the details naturally vary.
But, if the landscape of fear changes over the course of a mere day, how long does it take animals to adjust to changes in human activity? Animals are, after all, capable of learning and, while it would likely depend on the animal species in question, we can easily imagine them becoming more or less wary as the human activity around them waxes and wanes. For instance, a study at a recreation area in Utah showed that mule deer and raccoons are less active at weekends, especially near camping grounds.
If we're talking about changes in human activity levels, however, it's hard to argue that the largest disruption to daily life in modern times was anything other than the COVID pandemic. It's well known that many animals changed their behaviour once they realised that humans were not travelling about so much, and some scientific studies have attempted to quantify that.
One, for example, found that stone martens in Poland were more active in the early evenings during lockdown than they normally would be. Stone martens are nocturnal anyway, so would have had little motivation to exploit quieter days, but they could make use of more of the night if humans weren't around after dark in the evening.
Such studies continue to come out, such is the time taken to conclude data analysis, write everything up formally, and get it published and available. Most tend to focus on either urban areas, where we might expect the effect to be greatest, or recreational areas, where animal monitoring equipment may already be set up and that should have been almost totally deserted during lockdown. One new one, however, looked at the more complex matter of the interface between the two.
This study concerned the Jasper Ridge Biological Preserve operated by Stanford University in the San Francisco Bay Area. It's a 1,193 acre (4.8 km²) preserve described as an "outdoor classroom" for nature studies and education, lying on the traditional land of the Muwekma Ohlone tribe, and thus also referred to by the native name of 'Ootchamin 'Ooyakma. Crucially, it is almost entirely surrounded by suburban housing, close to the university. However, in addition to being a wild area in itself (there are cougars and rattlesnakes, for example), there is a narrow corridor linking it to the nearby wilderness of the Santa Cruz mountains. All of which gives it a different character from a typical city park.
On the 12th March 2020, all of the usual guided tours to the Preserve were cancelled, and four days later, so were all educational and research visits, with access restricted only to essential personnel. Educational services resumed in spring 2021, meaning that the former daily visits were paused for an entire year. Camera traps placed to monitor the activity of the local wildlife, however, remained running throughout.
In fact, they found relatively little effect. Of the six mammal species they were able to evaluate, only brush rabbits (Sylvilagus bachmani) - a type of cottontail found only along the West Coast - changed their behaviour to become notably more active during the day. Jackrabbits shifted the peak of their activity to be less active in the evening after the lockdown ended than they had been during it, but since they were already active then before it started, they don't seem to have noticed the beginning of the period, only its end.
The other four species studied, foxes, bobcats, cougars, and black-tailed deer, changed their activity little or not at all.
The researchers conclude that this may be because the animals in this particular area were already used to human activity, and moreover, human activity that didn't involve hunting and killing them. That is, they already felt secure moving about whenever they wished, and the fact that the humans that hadn't been bothering them in the first place weren't there any more didn't make much difference to them.
They also speculate that the brush rabbits being different had little to do with human activity. They are, of course, relatively small herbivores and had a great deal to fear from the foxes and bobcats. And, while those species were no more active during the day than they had been before, they were actually more active during their usual hunting times at night - perhaps feeling more confident in entering the area in general, rather than at particular times of day. And, with more predators around at night, it made sense for the brush rabbits to stay hidden then and cut back on their nocturnal forays.
But otherwise... well, it seems that there is more than one way to cut back on the landscape of fear.
[Photo by Eric Kilby, from Wikimedia Commons.]
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