How to Respond to a Dangerous Animal, US edition

On Halloween I gave a quiz to my Biology 102 students that included the question: "what real life animal are you afraid of?"

Only a few of them listed animals that are dangerous to humans living here in the US.  One in particular stands out as the most dangerous animal in the US; the one that causes the most harm and by far the most deaths every year!  He answered "humans."

The majority of answers were spiders and snakes.  In Massachusetts we only have two venomous snakes and one venomous spider.  It turns out to be very easy to avoid being hurt by these.  In fact, it's easy in most places around the world.

Let's start with snakes.

Step 1:  Don't pick up the snake.

Step 2:  See step 1.

In the United States most people who are bitten by snakes are bitten because they are handling them.  They may be trying to "move them someplace safer" or kill them or show off to their buddies after drinking too many beers.  On rare occasions a hiker will step near or on a snake and both of them get startled.  Most snakes can feel the vibrations of your footsteps when you're out walking and will move away from you.

Timber Rattlesnake (above) by Tony Alter

Copperhead (Right) by Ltshears







Neither of these snakes occur in the part of the state where I teach!





Statistics time.  On average six people are killed by venomous snakes in the US each year.  Twenty one people are killed by dogs.  Fifty four by lightning.

Which one are you worried about?



OK, but what about spiders?

There are very few species of venomous spiders in the US - they mostly fall into two groups - the black widows (easy to identify) and the brown recluses (harder to identify, much less common and less dangerous when they do bite).


Black Widow by Shenrick91

[I did not post a photo of a brown recluse because when I searched for photos there were several distinct species listed as brown recluse and, not being an arachnologist, I didn't want to post an innocent species' photo by mistake.]

Most spider bite wounds are not caused by spider bites (if you didn't see the spider don't assume spider bite - many types of insects also bite and many bacterial skin infections mimic spider bites).

How do you avoid dangerous spider bites?

Step 1:  Look before you put your hand into that dark space.

Step 2:  Don't pick up the spider.

According to a report in the International Journal of Dermatology, there were a total of 36 deaths from black widow bites between 1965 and 1990.

Umm... That averages out to 1.4 per year.

And we now have an antivenom.  So in the first decade of this century there were zero reported deaths.

And deaths from the Brown Recluse are even less common.

So WHY are you afraid of snakes and spiders?