Footprint in the Garden

Sometimes the visitors to your backyard habitat, come and go under the cover of night. We don't know they've dropped in unless they leave a calling card. 

This morning, we found this print in some damp soil. At first glance it looks like the handprint of a tiny person. But I don't think we currently have any trolls or gnomes. 

Typically, a "tiny handprint" appearance is the sign of a North American raccoon. We questioned that at first because the raccoon usually has plumper ends to the digits and visible claw marks. However, it must have been how the animal was walking and the dampness of the soil. 

We have been seeing raccoons off and on since last summer. At about two inches across, this is probably an adult raccoon.

Responding to a Common Threat

This morning I awoke to a family of western scrub-jays vocalizing alarm calls. Looking out the window I was intrigued to see a crowd of birds gathering rather than fleeing. Perhaps they only understood the call to mean “trouble” and they wanted to see the source for themselves or perhaps they comprehended specifically what the scrub-jays were alerting and wanted to verify the veracity of the declaration.

Within moments two adult ravens arrived and they took to immediately hazing the threat that seemed to be about 40 ft up along the trunk of a large eucalyptus tree.  Birds of all shapes and sizes–California towhee, spotted towhee, northern mockingbird, Nuttall’s woodpecker, Bewick’s wren and three Allen’s hummingbirds–gathered to see the troublemaker. Some, like the courageous hummingbirds, flew in and out of the foliage near the threat.

My first thought was: great horned owl. A great horned owl has been hooting from the pine tree in the evening and early morning for most of August. We’ve seen the commotion crows and ravens will make as they try to drive a great horned owl out of a tree.

As the ravens took turns diving past the thick growth covering the tree’s trunk, I could hear rustling and occasional strips of bark falling. Then through the foliage I caught a glimpse of the threat: the masked face of a raccoon. An egg thief had been discovered in its daytime refuge and the birds wanted it gone. The young raccoon was slowly making its way down the tree, trying to find a thick patch of branches to hide in for the day. This teenage raccoon has been prowling the area at night.

The political astuteness of birds always amazes me. A scrub-jay poses a predatory threat to a nesting hummingbird. Scrub-jays chase ravens away from their own nesting territory. But here, the birds all saw the raccoon as a greater threat and they quickly banded together in an alliance against a common foe.

If only we humans could trust our long evolved instincts. When one among us breaks the social contract and kills using agents of mass destruction, the benefit of all should be an aligning force encouraging us to make political alliances of the moment. Those who do not act together against such a threat will all suffer the consequences down the line.

Discovery in the Night Garden

Even at night, the yard is filled with biodiversity to be discovered. This common orb weaver spider was getting an early jump on Halloween and building a foot-wide web along the stairway. This wasn't a chance event. This spider specifically was building its web across an area busy with insects attracted to our porch light.

There was another more unexpected visitor at dusk–a young raccoon.

Its glowing eyes prompted us to call it "zombie coon."

The flash from my friend's camera reflected perfectly off of the raccoon's tapetum lucidum. This is an adaptation that allows night-time creatures to see well in the dark. Light that did not directly strike the retina is reflected off of a substance in the back or along the side wall of the eyeball so that it has a second chance to pass through the retina. This allows the greatest amount of available light to reach the optic nerve for vision. 

Tapetum come in a variety of shapes, are located in a variety of places in the eye and are made of a variety of reflective substances. The amazing thing is that this adaptation has evolved in many different nocturnal animals. Alligators and crocodiles, canines (dogs, wolves, coyotes), felines (cats, big and small), ungulates (prey animals like cattle, antelope, deer), rodents and rabbits, sharks, owls and dolphins all have tapedum. 

As members of Order Carnivora, we think of dogs and cats as being closely related to each other. What fascinates me is that the tapetum in a cat (Tabby or African lion) is formed by riboflavin in the tissue along the sides of the inner eyeball, while a dog's tapetum (terrier or wolf) is formed by zinc crystals in the back of the eye. This is a wonderful example of evolution in these two different branches of Order Carnivora.

Raccoons are in the Suborder Caniformia with canines (the same evolutionary branch) and therefore what you see in the photo is the white light of the flash reflecting off the zinc crystals at the back of the eye and streaming back through the pupil. Amazing isn't it? 

In another example of evolution, the tapetum in members of Order Artiodactyla (hippos, deer, antelope and bovines) is formed by collagen in the back of the eye. Whales and dolphins have a tapetum with the same collagen structure. Fossil evidence and DNA have now demonstrated the close evolutionary relationship between whales and hippos.

Most primates, including humans, are one of the few groups of mammals that do not have tapetum. Without fire, or man-made light, humans do not see well in the dark.

Discovery is all around you!

Creating a Garden That Attracts Wildlife

For many people the idea of wild creatures in their garden means rabbits and deer eating plants to the ground while birds and squirrels pilfer the fruit trees. While this can definitely be true, if you create a balanced ecosystem in your yard, the plant eaters will be moderated by the predators.

Get Clean and Green
Before you can think about attracting beneficial wildlife, clean up your act. If you wouldn’t drink it or eat it - Don’t Put It On Your Yard. “But there are aphids on my roses,” you say. Spray and the aphids become resistant, their numbers wax and wane. You continue to spray and take on the mindset of a Four-Star General mired in a losing battle. STOP!

No one wants to eat an insect packed full of insecticide. If the aphids get really bad spray them off with the hose. Aphids are not transportation wizards. Knocked off their home plant, many won’t survive. I noticed a group of aphids starting to flourish on my roses the other day, but so did the bushtits. These small birds, the size of a hummingbird, are voracious insect eaters. They scour my roses every few days and voilá, no aphids. I do nothing but watch. Did this happen all a once, NO. So get started today. Stop with the insecticides and herbicides, no one wants to live in or eat at a toxic waste dump.

When Reestablishing An Ecosystem Start Small
Think of your yard as an island, an oasis. As on all islands, the foundation of an ecosystem is the plants. Go Native with your plantings, like this beautiful Fremontia or flannel bush. You will save water, avoid frost damage and begin to attract the smallest wild voyagers, insects and spiders.

If your first response is “No way, insects mean infestation,” let’s talk. White flies infesting your favorite hibiscus? Japanese fruit beetles on your apricot tree? I have two things to say: nonnative insect on a nonnative plant. Native plants have evolved to defend themselves from native insects. Infestations typically occur on plants that have no natural defenses and with insects that are out of control because they have no predators.

If your response is “Uck I don’t want insects, I want to attract birds and real animals,” Let me give you a moment to rethink. A yard without insects and spiders is a Dead Zone.

Arthropods, the class of animals that includes insects, spiders, millipedes, crustaceans, etc., make up 85% of known living animal species. Their biomass is greater than ALL other animal species combined. That’s right, all the whales, elephants, fish and people in world do not weigh as much as the ants, flies, bees, beetles, spiders and krill. You can not have an ecosystem without them.

Open for Business
Think of your island of habitat as a resort with a reputation to maintain. You need three basics: clean water, safe food and safe living quarters. Water can be as simple as a low dish on the ground rinsed and refilled every other day. Moving water is more visible, but not necessary.

For shelter, provide rock mounds or logs for reptiles. Trees are a must for birds, but shrubs are important too. Many native birds, prefer to nest at a mid-height 5’ - 20’ off the ground. If trees aren’t possible a perch that offers height and a good view will help birds feel safe. (Trees provide roosts for birds of prey also.)

Native plants and insects will provide food. Adding a bird feeder or bird house bumps you up from a four to a “five-star” habitat, but they aren’t necessary. A bird feeder, however, will quickly bring seed-eating birds. Bird activity attracts insect-eating birds. They know the seed-eaters will watch for predators. Besides, it’s like choosing between a restaurant that is busy and one that is empty. Which one would you tend to try first? Fruiting or nectar-producing plants will also add to the variety of your visitors.

Safety is a priority. If you want lizards, amphibians or birds you can’t have an urban tiger, a domestic cat, prowling the grounds. Most dogs have less of a need to hunt and can get along with non-mammalian wildlife. Our dog actually watches the hummingbirds at the feeder.

Like any resort, word of mouth, can make or break you. Stagnant water, poisoned insects or a cat lying in wait by the bird bath can turn visitors away. And they will tell their friends. Here again, when you have a bad experience at a restaurant, you think twice before returning.

Something Furry
This is where a backyard habitat becomes more complicated. Humans have reduced native mammalian predators because of our own fear. These larger predators are frequently our predators. Wolves, bear, mountain lions, heck even bobcats and coyotes scare us. I’ve had a coyote looking in my French doors and one night while I was home alone, I could sense something was watching the house. It was a coyote out front.

A coyote is generally not a threat to humans, but it can be disconcerting to have something fairly large hunting in your backyard. However, without these predators rabbit and deer populations can get out of control. We are just in that foothill zone where we occasionally have a rabbit and it is typically preyed upon by someone’s dog or one of the hawks or owls.

Bats however are mammals you can attract to your garden without worry. As insect predators few birds can match them. To attract bats, open water, like a pond or pool, is a plus. Nocturnal insects often fly over water. A bat box or large trees can provide shelter.

Nonnative brown rats and mice can be a problem. They depend on human castoffs, but rats will also prey on the eggs and young of reptiles and birds.

Raccoons, skunks and introduced opossums can also be a challenge. As occasional visitors, raccoons and skunks are valuable snail and grub predators, but you don’t want to feed them. They will be healthier and live longer as wild creatures. To ensure that you aren’t feeding them or attracting coyotes, feed your pets in the house. Pet food bowls can be very attractive to wildlife.

Saving the World
When you create habitat in your backyard I believe you are helping to save the Earth one small piece at a time. Global warming, species extinction and toxic pollution seem insolvable problems, but look out at your yard, the solution starts RIGHT HERE, RIGHT NOW. Restore the native habitat in your yard and help save the world.