VIC LEIPZIG AND LOU MURRAY
Our story started a few weeks ago at Irvine Regional Park with Vic's
bird class. We expected nighthawks, owls and poorwills, all birds
that are active at night. What surprised us was hundreds of western
toads on the park roads.
Apparently, toads like the warmth of the asphalt. They congregate
there in the early evening before hopping on to do their toady
business of catching insects and making baby toads. OK, technically
making baby toads involves eggs that are laid in water, that hatch
into swimming tadpoles, that metamorphose into toads by growing legs
and losing tails, but that's not where this story is going.
The large number of toads at Irvine Regional Park led to the
innocent question of whether there were still western toads here in
Huntington Beach. They're on the species list of Shipley Nature
Center, but we had never seen any.
In the interest of science, we decided to informally survey
Huntington Beach's amphibian population. Unfortunately for us, this
is best done at night. Picture the two of us prowling around the
swamps of Huntington Beach with flashlights. Now picture the
Huntington Beach police force actively investigating all suspicious
nighttime activity. Yep, once again we attracted the attention of law
enforcement.
First we did some research. Amphibians are an order of vertebrates
that includes frogs, toads, newts and salamanders. The first
amphibians crawled out of the primordial slime about 360-million
years ago, long before the age of dinosaurs. Now, after surviving for
millions of years, frog populations are declining all over the world.
Suggested causes for the decline include pollution with
pesticides, herbicides, heavy metals or other toxics. Other possible
causes are habitat fragmentation and loss, fungus and infectious
diseases. Predation by -- or competition with -- introduced nonnative
species also takes a toll. But frogs are declining even in remote
areas with pristine water, so global climate change or increased UV
irradiation due to loss of the ozone layer are other possibilities.
While different factors may be causing declines for different
species, one thing is certain. Amphibian populations are declining
all over the world and our area is no exception. Here in southern
California, the species known as the red-legged frog was once common,
but is now limited to one remote area in Riverside County. Another
southern Californian amphibian, the arroyo toad, is now endangered,
and may no longer be breeding in Orange County.
