"Snakes. I hate snakes." - Indiana Jones, Raiders of the Lost Ark.

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How many of you have been walking along a trail or in your neighborhood during a spring afternoon, and unexpectedly came across a snake bathing in the sun? Or how about the first time you saw a snake at a zoo, nature center, or on the television? Try to remember the reaction that you had. Were you afraid? Were you excited? Did you sense danger? 

If you felt fear, have you ever considered why? Was it the way the snake looked (opposite of humans; hairless, legless, no ear lobes, skin, or eyelids)? Was it the way it moved, using its strong muscles to slither around or hold most of its body up into the air? Were you frightened by its behavior as it coiled up, struck in your direction, or slithered away to avoid you? Did you recall that some snakes are venomous, and the fear of death aroused an uneasy feeling in you?

If you felt any of these things, well, you are not alone. After all, it is scientifically suggested that humans have evolved to fear snakes - just as snakes have evolved with appearances and behaviors to scare you - and any other potential predator. In a world full of hungry animals, snakes are just another creature trying to survive.

There are almost 3,000 species of snakes in the world, and it seems as though Indie from the Indiana Jones series hated just about every single one. While there are many species of snakes to fear (like the 600 or so species that are venomous, such as rattlesnakes and coral snakes here in the U.S.), a majority of them are harmless and nearly all are, in fact, beneficial to us. Why? Because of what they do to survive! What do they do to survive? They eat! What do they eat? Potential disease or parasite carrying rodents and birds! Sometimes other snakes and lizards! They don't want to eat humans... well, that is, unless you look like J.Lo. or Ice Cube.

Snakes are predators, but most of them are not BIG predators - so they cannot eat BIG prey. In my backyard, the typical diet of local snakes includes field mice, small rats, and birds (snakes in other places will feed on insects, eggs, and invertebrates). Gopher snakes, garter snakes, king snakes, and rattlesnakes all dine in the same cafeteria, like my backyard. The result? I have no need for mouse traps!

Different species of snakes have different approaches to eating, and these adaptations make them more efficient hunters of their prey and encourage biodiversity. While some species of snakes constrict or suffocate their prey (i.e., Common kingsnake), pit vipers - the venomous kinds of snakes - strike at their prey with fangs and inject a lethal poison. Some snakes, especially after being in captivity, do not constrict but simply scavenge recently killed prey. These feeding habits can also be important defensive mechanisms.


One of the coolest things I have ever witnessed was a little cafeteria bullying between a juvenile Northern Pacific rattlesnake (Crotalus oreganus) and a Common kingsnake (Lampropeltis getula californiae). In an epic battle like this - who would you expect to win? The snake with the poisonous fangs or the snake with the super squeeze muscles? Well, there is a reason why the kingsnake is called such: it is the king! As the only snake known to be immune to rattlesnake venom, the kingsnake is 
notorious for feeding on rattlesnakes. Now that is a crown I wouldn't mind wearing.

As it fails to inject a lethal dose of venom into a kingsnake, this rattlesnake is on its way to becoming a meal itself.

Often when we talk about predators like snakes, it is hard to imagine any creature that could turn a snake into prey. But the reality is that snakes are prey to predators higher up on the food chain - primarily raptors and coyotes (and sometimes a kingsnake!). As snakes help keep population numbers of creatures lower on the food chain in check, top-level consumers control snake populations - all contributing to a healthy ecosystem. But if all of the snakes disappeared, populations of rodents could explode - not good news for humans or the food chain.


In order to be a sustainable contribution to the food chain, snakes have evolved over time to not only avoid predators, but to be excellent hunters. Their coloration and patterning is often a form of camouflage, varying from species to species depending on their habitat. Some snakes even have warning colors or patterns. Following the old adage, "Red on yellow will kill a fellow, but red on black is a friend of Jack," a coral snake is an excellent example of warning colors, or aposematic coloration. Other snakes, like gopher snakes, blend in perfectly well to their surroundings.

The coral snake is not a pit viper like a Rattlesnake,
but is the only other kind of venomous snake found in the United States.
 Its aposematic coloring follows the old saying,
"If red touches yellow, you're a dead fellow." snakecare.org

Another type of survival technique found among snakes in my backyard includes Mullerian mimicry, where a non-threatening snake will behave or mimic a dangerous snake. A popular example is that of a gopher snake posing as a rattlesnake: gopher snakes will flatten their heads to take on a diamond shape (a key indicator that a species is a rattlesnake, which has a diamond or triangle shaped head to store the pits in its cheeks), and shake their tails on the dry grass to make it sound like a rattle. Furthermore, gopher snakes have evolved over time to resemble rattlesnakes, and both species usually need a second look to ensure correct identification.

With a flattened head and nearly "ready to strike" pose, this gopher snake mimics 
many of the threatening traits of a Northern Pacific rattlesnake. 
A gopher snake's appearance and behavior - especially when threatened - 
is similar to that of a rattlesnake's, often leading to species misidentification. 
Photo courtesy of Krist Jensen.

If you felt nervous around a snake, perhaps you were feeling the very emotions that snakes have evolved to give you. In order to survive their environment, appear intimidating to potentially dangerous creatures, and do well as hunters, snakes present themselves with a particular nerve-wrecking style. Perhaps the next time you come across a snake, you'll take a gander at its look and behavior, and you may have a good idea as to what its intentions really are - and that, I can almost guarantee - is just to survive.  

Spring is germinating!

What does a lot of rain followed by an abundance of warm sunshine in the middle of February mean in the Bay Area?


For some it means a quick getaway to the beach before the rains return, or perhaps that "global weirding" is really starting to mess with our heads. But when the sun makes it out in the wintertime, sometimes the last thing people want to do is look at the ground (they're too busy thanking the sky for the warmth). But personally, I find it almost impossible to take my eyes off the things going on at my feet - the growth of new plants and fungi. Without this process, called germination, spring would never have the refreshing sense it provides us with every new bloom.

The germination of this California buckeye began
 at Black Diamond Mines Regional Preserve in Antioch, CA.

Before a California buckeye is a full-grown tree, it is a seedling. Before it is a seedling, it is a seed, or a buckeye gall. When the rains come and is followed by an abundance of warm sunshine (ideal growing conditions), a physiological signal occurs within the buckeye gall, triggering it to begin sprouting. This is called germination. First the root forms and grows into the ground, and suddenly a young tree is rapidly sprouting towards the sky (a sporeling grows from a fungi spore). This is an important signal, not only for the plant and its growth, but for the insects, birds, and other wildlife that depends on this process every year for food and shelter.

But the problem with germination in recent years is the timing: germinating plants like California buckeye and oak trees have been experiencing germination earlier because of abundant rains followed by short periods of sun shine, once again followed by rains. If the plant germinates during a short window of ideal growth time and then drowned, there is a strong likely hood that the plants will not survive. This can have impacts on a plant population, and with fungus, can reduce the numbers of available decomposers. This in turn impacts the nutrient cycle and the food chain.

An acorn in the early
stages of germination.

So "global weirding" appears to be messing with more than just our heads. It is also messing with the most critical stage of a plant's life cycle by causing germination to begin earlier, when ideal conditions are more temporary and well, less than ideal. So the question becomes, How refreshing will spring be when it no longer begins the same?