Lessons From the Field #3: Don’t feed the !@(*&# wildlife

This past March I went on a great geology field trip across northern Arizona, eastern California, and southern Nevada and Utah.  The biggest stop on the trip involved two days in Death Valley National Park.  This park is huge, and although it’s the hottest, driest, most inhospitable place in North America, there is a ton of cool stuff to see.  Here I’m focusing on why it’s so hot and dry, and how that’s precisely why you shouldn’t feed the wildlife here (or anywhere, but especially here).

Looking north up the valley from Mosaic Canyon.

First, why is this the driest place in North America?  High mountains create a rain shadow effect.  In North America prevailing winds carry clouds eastward.  As the clouds move up over mountains, they tend to release most of their moisture on the windward side.  Once the clouds pass over the mountains, they tend to have low moisture.  In mountainous regions, this rain shadow effect multiplies as clouds travel over each range.  The Sierra Nevada Mountains and the Panamint Range west of Death Valley completely dry out the approaching air in this manner.

Looking southwest across Badwater Basin from the mouth of Natural Bridge Canyon.  The Panamint Range is in the background.

What little precipitation occurs collects in the lowest spots on the valley floor.  The largest such location is Badwater Basin, shown above.  That is indeed water you see, but it’s not fit to drink.  It’s extraordinarily salty…hence the name “Badwater”.  The bottom of the valley is a 200-square mile salt flat.  The enclosed basin collects mineral-rich water that runs off the mountains.  After the water evaporates, it leaves behind these minerals.  Over a great deal of time, they collect into vast deposits.

Salt. Lots of salt.

Next, why is this the hottest place in North America?  Death Valley is the lowest basin in North America’s basin and range province.  Here the crust is slowly being pulled apart by extensional forces.  The crust cracks and forms faults, and some blocks drop along these faults relative to the surrounding blocks.  The dropped blocks form valleys (basin) and the higher blocks form mountains (range).  This alternating basin-range sequence continues for hundreds of miles.

Looking west from the Amargosa Range across Death Valley to the Panamint Range.

Badwater Basin is about 280 feet below sea level.  The large amount of sunshine, high atmospheric pressure, low humidity, and the enclosed nature of the basin help create and trap heat.  It got above 80 degree Fahrenheit in March, and in the summer it gets around 130 degrees in the daytime.

Despite the hostile landscape, a number of organisms make a living here.  Among them are coyotes (Canis latrans, Canidae) that manage to find enough food, water, and shelter to survive.  What doesn’t help them survive, however, is when ignorant people feed them.

Ignorant person tossing food to a coyote in Death Valley National Park.

While this may seem like a nice thing to do (it certainly feeds the animal in the short term), in the long term it actually hurts the animal.  First, animals learn to beg for food from cars, bringing them close to roads where they can get hit.  Second, animals can start pestering humans living and camping in the area, becoming a nuisance and a possible danger that can warrant their extermination.  Third, animals can learn to rely on people for food instead of hunting.

When there are a lot of generous tourists around, things are great for the animals.  Tourism plummets in Death Valley in the summer, however, when few people brave the scorching heat.  Animals that have learned to rely on people for food can suddenly find themselves starving.  This can negatively impact their health and survival, or it can lead them to invade human settlements in search of food.  Once they start harassing and threatening people, they can find themselves on the wrong end of a rifle.  While this is a problem everywhere, it’s especially alarming in Death Valley.

So a note to people like the guy above:  Do the animals a favor and don’t feed them.  They lived here for a long time without your help, and your “help” now may very well kill them.


About Jeremy Sell

Science and nature nerd.
This entry was posted in Geology, Lessons From the Field, National Parks, Vertebrate Zoology and tagged , , , , , , , . Bookmark the permalink.

14 Responses to Lessons From the Field #3: Don’t feed the !@(*&# wildlife

  1. Jim Martin says:

    I completely agree with your first and second point:

    ‘First, animals learn to beg for food from cars, bringing them close to roads where they can get hit. Second, animals can start pestering humans living and camping in the area, becoming a nuisance and a possible danger that can warrant their extermination.’

    And for those two reasons alone I completely agree with your premise that it is bad to feed them.

    But I question your third statement… I’ll caution this with the ‘I haven’t searched the literature recently.’

    here’s your assignment (if you choose to accept it):

    Do wild animals loose their hunting ability once their diet has been enhanced by humans? Has that been shown?


  2. Jim Martin says:

    give examples.


  3. Jeremy Sell says:

    It may be more accurate to say that young animals don’t develop adequate hunting skills when they’ve learned to depend on humans, rather than say they “lose” their hunting skills.


  4. Jeremy Sell says:

    Peirce, K.N. and L.J. Van Daele. 2006. Use of a garbage dump by brown bears in Dillingham, Alaska. Ursus 17(2):165-177.

    I was unable to get full access to that article, but the introduction contains the following:

    “Grizzly bears in Yellowstone National Park relied heavily on garbage dumps (Craighead et al. 1995). When dumps were closed in the early 1970s, human injuries occurred and many bears were killed in control measures that reduced population size. Bears that survived experienced declines in body weight, reduced reproductive success, a slower maturation rate, and decreased survival (Craighead et al. 1974, Knight and Eberhardt 1985, Stingham 1986, Schoen 1990, Robbins et al. 2004).”

    Without the full paper I can’t trace back their citations.

    The grizzlies seemed to have largely lost either the will or the instinct to forage naturally. If they were reared on human refuse, they never would have developed natural foraging behavior. If they were adults that became acclimated to foraging refuse, they may have “forgot” how to forage normally.


  5. Jim Martin says:

    I expected the bear/garbage dump argument. That situation is different than the one you put out.

    ..I’ll argue that in the Death Valley example we are not seeing anything approaching that quantity, or, more importantly, reliability, in nutrient inputs. The tourist garbage in that desert I think is a more ‘winning the lottery’ thing than having a reliably placed reward like a garbage dump.

    Albeit the odds of winning are higher now than they were before humans brought them left over bits of hamburgers…


  6. Jim Martin says:

    The crux of the challenge lies in defining how enhanced their diet is, I suppose. Further, food reliability and transfer of animal traditions (the learning of the hunt from the older ones/peer group) also play a role.

    I wonder how much of the coyote’s food budget is human derived?


  7. Jeremy Sell says:

    If a coyote is fed once from a car and returns hoping for the same, and is fed again, and again, doesn’t that become a reliable reward? If that pattern holds up, I could see them learning that cars are a reward in the same way the bears learned the dumps were a reward.

    For what it’s worth, the driver above threw out quite a bit of food over several minutes (I think it was meat)…a pretty substantial reward for the coyote. The park gets quite a bit of tourism in the cooler months, and most of the people certainly have quite a bit of food on them for camping. If even a small minority of them have the mindset of the above driver, then cars could become pretty reliable food sources for coyotes.

    I couldn’t find any research closely related to this situation. Think there’s grant money for something like this?


  8. Jeremy Sell says:

    Another question to ask is “why was this coyote hanging around the road/cars in the first place?” I suspect normal coyote behavior is to run from people/cars, but this one didn’t. I suspect it was already conditioned to expect a reward from a car.


  9. Jim Martin says:

    oh, I agree, these animals are becoming highly conditioned… I also agree that getting fed 7 weeks in a row in the same place (even if it is only once a week), will entrain the animal to come back to the spot.

    I’m intrigued with the question of where the break/tipping point is in maintaining self sufficiency (ability to forage independently) in the face of irregular food inputs.

    In the case of the coyotes near the highways there is a peculiar trade off, you named it yourself: great food rewards (=increase chance of survival and reproductive fitness) vs. vehicular canicide (=zero to lessened chance of survival and reproductive fitness).

    This is an interesting research topic. There must be somebody working on problems like this…


  10. Jeremy Sell says:

    I see your point, and the “tipping point” would be something worth investigating.


  11. Interesting aside says:

    2 somewhat related stories: At Sunset Crater, the raccoons fed regularly from our dumpsters. When the dumpsters were raccoon proofed, they regularly destroyed window screens and got into our houses for the trash until they were “dispatched.” And in Salt Lake City, the California Gull was migratory until they learned to live all winter there on the landfill.


  12. Pingback: Lessons From the Field #4: Elevation matters | The Life of Your Time

  13. Pingback: Textbook Cross-Bedding | The Life of Your Time

  14. Pingback: Antelope ground squirrels | The Life of Your Time

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s