[Instrumental piano music]
I think of Sonoran pronghorn as a desert relic. They’re unique to North America,
and have special adaptations to this harsh environment surrounding us.
Back in 2002, after a year of severe drought, the Sonoran pronghorn population in the United States
crashed to just 21 individuals. Wildlife biologists think we were just months away
from losing the entire population of Sonoran Pronghorn in the United States.
Part of the reason Sonoran pronghorn are in trouble today is because of human activities.
As a result, we have a responsibility to help restore this pronghorn and make
sure it doesn’t go extinct. And more importantly, we know that’s possible.
[Music fades out]
Hi my name is Stephanie Doerries and I’m the Sonoran Pronghorn recovery coordinator
and wildlife biologist at Cabeza Prieta National Wildlife Refuge.
I have been working with the Sonoran pronghorn for more than 11 years.
The Sonoran pronghorn is a subspecies of American antelope that are especially adapted to live in
the desert’s harsh environment. They are 20-40 lbs. lighter than their grassland counters parts,
and their fawning and mating seasons are shifted to occur
earlier in the year so they correspond with the desert’s bimodal rainfall patterns.
Sonoran pronghorn, like most desert species, do not occur at really high densities.
Pronghorn need a larger area to roam around on
to get enough food to eat than they would if they lived in a grassland, for example.
When an animal doesn’t occur at a very high density,
then they’re really susceptible to any drought for example that comes along. And so we’re
very concerned about the effects of droughts on Sonoran pronghorn. On top of that, when humans
started to settle in the desert southwest, they started to fragment pronghorn habitat.
Pronghorn aren’t very good at crossing fences. They have to be built in a special way.
So when you had a lot of people coming into the area with cattle and other
livestock and grazing those livestock, fences potentially inhibited pronghorn movement.
additionally, the livestock had certain types of diseases that they pronghorn were susceptible to
because they’d never been exposed to them before.
It’s these four main factors - habitat loss and fragmentation,
drought, and disease, that have predominantly caused this decline in Sonoran pronghorn.
Today, our management efforts and our conservation efforts generally fall into
two different categories. The first is captive breeding. This allows us to have pronghorn
to translocate to other areas so that we can supplement existing populations and,
more importantly, start additional populations of Sonoran pronghorn in the United States.
We have two captive breeding pens for Sonoran pronghorn.
The one on Cabeza Prieta National Wildlife Refuge is a whole square mile in size.
It was built in 2003 and the first pronghorn were brought to the pen in 2004.
The second category of conservation efforts actually focuses on actually supporting
wild pronghorn, and the pronghorn that we release out into the wild.
What we’ve found is that Sonoran pronghorn will readily drink water if it’s in the appropriate
habitat. So we’ve started providing pronghorn with supplemental water, and in certain areas,
supplemental forage, so that they have food to eat predominately during that hot dry season,
that period where it starts to get really hot in about April, until the monsoon rains come in July.
In addition to the supplemental waters and forage stations,
we also have a couple forage enhancements plots, where we irrigate native vegetation
that pronghorn like to eat so that during those very dry periods pronghorn have a place
where they can go so that they can have good high-quality natural forage to eat.
The last survey of Sonoran pronghorn in the United States estimated 257 individuals
in the area where there were only 21 individuals back in 2002.
We have 458 Sonoran pronghorn in the United States today.
Sonoran pronghorn are unique to North America. They’re they fastest land
mammal on the continent. They don’t occur anywhere else in the world.
With the conservation success that we’ve currently witnesses we know that we can eventually,
through the strong partnerships that we have in the Sonoran pronghorn recovery team, can take
this species from endangered and down list it to threatened, and then get them delisted entirely.