A coyote out in the early morning.
It’s a sunny afternoon. Camille Boag and her dog Rue begin their regular walk around Echo Park Lake. They’ve only just started when Camille stops to take a closer look under the bushes.
She grabs a stick and pokes at a mystery item, but it’s not what she’s looking for. “Domestic dog,” she says to herself, and continues along the path. As a volunteer for a community science project, Camille has agreed to come here each month to document coyote scat (the scientific term for poop). Coyotes pass through the park unseen at night, but they leave behind scat to mark their territories.
With practice, she’s become something of an expert at telling the difference between dog and coyote droppings. Coyote scat has a lot more hair and fur in it, is much more likely to contain bones and seeds, and is usually twisted and tapered at one end. Dog poop, on the other hand, contains mostly mushy pet food and is shaped like blunt logs.
It might seem strange, but this is one of the best ways for researchers to learn about the lives of nighttime animals. You can tell a lot about an animal from its poop.
Coyotes were once called the ghosts of the plains, because they were heard more than they were seen. This is still true. Their calls, familiar to anybody who lives near our hills and mountains, help coyotes keep in touch with their pack-mates, even when they can’t see each other. Perhaps they’re wishing each other a good morning or warning their comrades to be careful.
Most coyotes follow a daily routine: patrolling their territory while looking for food. Imagine a coyote as it reaches a familiar rock near the edge of its home range. Like a domestic dog on a fire hydrant, it uses urine to mark its turf. Think of it as a note written with pee, sending a message to unfamiliar coyotes who might be nearby. “Stay away,” the coyote declares as it sprays the rock. “This seat is taken.”
Let’s imagine a coyote wandering through a golf course. Food is abundant in the hills and yards of Los Angeles. While coyotes will eat a huge variety of plants and animals, living or dead, one of their favorite meals in urban areas is the cottontail rabbit. Rabbits have fewer places to hide on the golf course than in the brush-covered hillsides—the coyote spots breakfast hopping along near the ninth hole. But the coyote just isn’t fast enough, and the rabbit escapes.
In the early a.m. hours, the coyote emerges from the hills to saunter down Sunset Boulevard. This is risky business—like every other animal that calls Los Angeles home, coyotes often become roadkill. But it is more likely to survive a crossing in the middle of the night than during the day.
Because it’s a quiet night, our coyote crosses easily. Safely back on the sidewalk, it turns its head to the left and sees driveway after driveway. Having missed breakfast, the coyote is hungry. And it knows that where there are driveways, there are backyards. The coyote listens but hears nothing. The coast is clear. As it jogs down one driveway, it notices the porchlights, attended by light-seeking insects. Small non-native lizards are enjoying a feast thanks to those lights. While a lizard might make a good appetizer for a hungry coyote, ours knows it can find food more easily in the backyard.
As homeowners and families sleep soundly inside, the coyote quietly moves from yard to yard. Fruit trees have dropped oranges and grapefruits, and one yard has a garden with ripe strawberries. It’s not rabbit, but fruits and berries make a fine feast, and, unlike lizards and rabbits, they don’t run away.
One hour and a dozen backyards later, the coyote gets lucky. A dog owner has left out a big dish of water. Raccoons were at the dish first, but when they sniffed the coyote’s scent, they were off in a flash of black and gray fur. The coyote drinks in total privacy.
At dawn the sky turns pink and road traffic starts to pick up. As the city’s nocturnal critters settle into sleep, people are waking up to their alarms and getting ready for work and school. Having survived the big city another night, the coyote makes its way home to the protection offered by dense chaparral. (But not before leaving a smelly gift behind for some community scientist like Camille to find!) The coyote hears its siblings and parents yipping and yahooing. It returns their calls with one of its own. “I found some tasty food,” it might say. “But now I’m heading home. See you soon!”
As long as there have been critters on this planet, there have been those that sleep through the heat of the day and emerge to go about their lives at night.
The Earth’s daily rhythms have continued more or less unchanged for billions of years. Night is darker and cooler; day is brighter and warmer. Animals—including humans—have evolved to expect these predictable cycles. Plants, fungi, and bacteria also have these internal clocks, known as circadian rhythms.
At night, our artificial lights make parts of the city bright as daylight, altering the night sky with what’s known as light pollution. Changing the basics of night and day can alter the circadian rhythms of animals, insects, and other organisms, even people.
Most birds sleep at night, and hunt and sing during the daytime. In the wild, male robins start singing just before dawn. But in cities like Los Angeles, streetlights can mess with their timing, causing them to start a few hours too early. And male northern mockingbirds usually only sing to find a mate during the day, but those in lighted areas continue to warble at night. Researchers suspect artificial lights trick the mockingbirds into believing it’s still daytime.
A little extra singing might not seem like a big deal, but it is. The birds could be wasting energy singing before their potential mates are ready to listen. Every calorie they burn by singing must later be replenished by eating.
Other changes happen when we have too much light. One study found that female frogs, which normally breed at night, were less choosy about their potential mates in brighter areas. The hypothesis is that they would rather mate quickly and then hide, because bright lights increased the risk that they would become somebody else’s dinner. Another researcher noticed that frogs near a football stadium stopped mating on game nights. If the frog pond was covered, blocking the glow from the bright lights, the frogs were happy to mate.
Some moths can use the light of the moon to navigate. When they mistake artificial lights for the moon they can circle endlessly. Of course, this is great for bats—a cloud of moths hovering around a light is a heavenly feast for them. However, if our communities were to switch to more efficient, darkness-protecting light sources, the bats would go back to finding moths the old-fashioned way. They find the lights useful, but not essential—a handy life-hack for surviving in the city. Without the lights, the bats would still be out there, using their sonar to chow down.
The good news is that there are some kinds of lights that cause a lot less light pollution than other kinds; if your city or neighborhood is talking about making the switch to these more efficient types, it’s worth supporting. Darker skies are good for humans and animals, and they help us see the stars more clearly, too.
The Yuma myotis bat prefers ponds and streams. Thanks to the lake at the La Brea Tar Pits, you can sometimes spot them along Wilshire Boulevard.
Plants are different at night than they are during the day. They may look the same from the outside, but their internal power systems run differently. In daytime they soak up sunshine for photosynthesis, the chemical process that creates energy for them and oxygen for us.
At night, plants can’t photosynthesize because moonlight is too weak (imagine trying to read a book by candlelight—if the candle was a block away). But plants aren’t just chilling out at night, getting bored. Many need nocturnal insects to visit their flowers and pollinate them. They may not be running their energy systems, but they’re still open for business and hoping for customers.
You can find one such plant, the sacred datura, in Los Angeles’s foothills and weedy lots. Nicknamed moon flower or, less charitably, jimsonweed or stinkweed, it’s an attractive plant that resembles a pumpkin vine growing low to the ground. Its dark, gray-green leaves, about the size of a child’s hand, have large, white blossoms, often displaying a purple inner core. These blossoms are pollinated by sphinx moths—insects about the size of a hummingbird, which are active mostly at night.
Want to see a sphinx moth, coyote, bat, or maybe even a bobcat? Many nocturnal animals go to bed before the sun is fully up, but if you’re out early enough, you may see the night shift before they clock out. Before most of the city is awake, you’ll have the roads and hiking trails to yourself and could be the first to find animal tracks or scat (the end of the night shift is also the start of the day shift, so you’ll see twice as much nature as usual). Though they can be harder to spot, the animals and insects that take to the night are important members of our wildlife communities. Without them, Los Angeles would be a very different place, even during the day.
