Cal State Northridge
College of Science &
Dept. of Biology
The Biology Department Newsletter
Volume 14: No. 1, Editor: J. Maxwell, Publisher J.W. Dole
California State University, Northridge
The Students' Forum
Bios invites articles written by students about their personal "biological experiences."
Interested students are encouraged to consult with the editor regarding their ideas.
About the student authors: Sandra Ng is a graduate student working with Dr. Tom Valone. David Riherd and Ann Tibbels are undergraduate students.
The Carnivore Project: Animal Tracking in the
Sta. Monica Mts.
by Sandra Ng
As people build homes in what was wildland, animals suffer. The habitat they need
is either lost completely or fragmented to such a point that the animals' very survival
is threatened. The problem is especially acute for large carnivores coyotes, bobcats,
and the like that wander widely and that occur in low population densities.
An effort, called the "Carnivore Project," was begun in 1996 to look at
the effects of habitat fragmentation on bobcats and coyotes in the Santa Monica Mountains.
The project is a cooperative venture between the National Park Service (NPS) and
two universities, UCLA and the University of Massachusetts. The mosaic of core habitat
mingled with patches of open space and urban areas makes the Santa Monica Mountains
an ideal study site for developing an understanding of how carnivores react to development
pressures and how their movement patterns are altered in a wildland urban interface.
Field data for the Carnivore Project are being gathered by both camera surveys and
radiotelemetry. Currently, the NPS is tracking 35 coyotes and 28 bobcats. Each animal
has a radio collar with a unique frequency. By using directional antennas, the movements
of each individual can be followed. From this, home range size and survival rates
can be determined. My role in the project is to coordinate these efforts.
Many habitat patches are connected by narrow corridors of suitable habitat. Others,
however, are crossed by freeways, a major threat to habitat connectivity. The extent
to which animals use corridors or are hindered in their movements by freeways is
unknown. My thesis research is an attempt to evaluate the importance of corridors
to carnivores in the Santa Monica and Santa Susana Mountains and in the Simi Hills.
I am using cameras tripped by an infrared beam to monitor carnivore activity. My
work will be done under the guidance of Drs. Valone and Dole.
If NPS ecologists and resource managers are to understand how wildlife populations
operate in a fragmented landscape, data of the sort I am seeking are crucial. Without
it, we are unlikely to preserve the wildlife in our local mountains for future generations
to enjoy. I feel very fortunate to be involved in such a great project, knowing that
I am making a contribution to local wildlife conservation efforts.
The Carnivore Project welcomes volunteers who can commit 40 hour / week for 10 weeks
or more. Course credit may be available. The NPS also has summer internship positions
in natural resources such as threatened and endangered plants, vegetation management,
landscape architecture, land use planning, and geographic information systems, and
in cultural resources, public affairs, computer science, and interpretation/education.
If interested, contact Dana Dierkes at (805) 370 2312.
A Costa Rican Odyssey: I
by David Riherd
Awe inspiring wildlife abounds in the tropical rain forests of Costa Rica. When I
first saw the gold scarab beetle I thought it was a gold brooch. Large metallic blue
butterflies fluttered and floated down the trails. Brilliant scarlet macaws and spectacular
toucans watched over the rain forest from the trees above. Even the sounds of the
rainforest could stir excitement and mystery. The incredible, almost eerie calls
of the howler monkeys dominated the forest like sirens.
The instructors of this course, on the biodiversity of Costa Rica, warned us repeatedly
not to wander off the trails due to the likely event of getting lost. But there John
and I were, late at night, chasing an enormous, beautiful red and brown frog through
the forest far off the trail. We were so taken by this frog that we almost forgot
about the notorious fer de lance, an extremely toxic and dangerous snake that is
a common threat in the rainforest. We were more concerned with catching and identifying
this unknown frog. Laughing hysterically, with my hand raised above the frog, I asked
John, "Do you think it's poisonous?" Laughing just as hard as I was, he
answered, "Probably." We were off the trail in fer de lance country, and
I was positioned to lower my hand down on a potentially dangerous frog. Everything
was so fascinating that we almost lost our senses. The frog got away, and luckily
we managed to find our way back to the trail withoug meeting any poisonous snakes.
The next time I go to Costa Rica I will keep my senses when I see an amazing creature
and stay on the trail.
For wildlife enthusiasts there's no place like Costa Rica. It's a country striving
to protect its magnificent tropical environment. I greatly look forward to the day
that I can return to this beautiful country.
Dr. Jim Dole, his wife Betty Rose, and entomologist Frank Hovore led nineteen students
through the tropical forest on a spectacular two week trip. The lodging, food, lectures
and tours were exceptional. My expectations of the trip were already high, but our
guides planned a trip that went beyond my greatest expectations.
A Costa Rican Odyssey: II
by Ann Tibbels
As you travel towards the equator, species diversity increases. Knowing this is one
thing, but to actually experience it first hand is another thing altogether. Last
summer I was lucky enough to experience the tropics as a student in the Tropical
Biology (Biol. 524) class.
The class consisted of 19 students, most of whom had never been to the tropics, and
three instructors. As our plane landed in Costa Rica, many of us commented on the
area's greenness, quite a change from southern California. But when I stepped off
the plane, the first thing that hit me was the humidity. Yet within a few days we
had adjusted and hardly noticed how moist it was. Once through customs, our pockets
full of Costa Rican colones, we were off to our first stop.
Before I signed up for the class, I had assumed that all tropical forests were the
same. I soon learned how wrong I was. Costa Rica has three types of forests, each
with its own specific and unique plants and animals.
Our first destination was a tropical dry forest on the Pacific side. It's called
a dry forest because it has a distinct dry season when the trees all lose their leaves.
But, fortunately for us, the rainy season had begun and the forest was green and
teeming with life. I was particularly surprised by the discovery of 6 foot high cacti
throughout the forest. I had never expected to see cacti in the tropics, yet they
were common. Another first for me were the fireflies, which (yes, I know) are not
flies but beetles.
Leaving the lowlands we traveled to the village of Monteverde to see a cloud forest.
Located high up in the mountains, right along the continental divide, the cloud forest
lived up to its name, for it was almost always shrouded in a huge cloud of mist.
The flora and fauna were very different from those of the dry forest. The vegetation
was lush and virtually every available part of the trees was covered with mosses,
ferns and bromeliads epiphytes, as biologists call them. The cloud forest was by
far my favorite place and I can now say that I had lunch on the continental divide.
The rainforest, the third forest type we visited, is found mostly on the eastern
lowlands. Tall trees, rain year round, and an abundance of epiphytes characterize
this forest. We stayed at a research facility used by scientists from all over the
world. As an aspiring scientist, I was thrilled to find myself surrounded by all
that knowledge and I hope one day be stationed at such a remote location doing my
own research. On the last night our class stayed at the base of an active volcano,
so close that when the clouds cleared we could see the hot lava glowing above us.
After the class ended a few friends and I explored the Caribbean coast and found
ourselves in another world, one with a strong Jamaican influence and a culture dramatically
different from that in other parts of Costa Rica. We lounged on the beach listening
to reggae, snorkeled on a coral reef, and enjoyed our beer with people from all over
the world. The highlight of our exploration was Tortuguero, a small island where
we saw sea turtles laying their eggs.
Overall, I saw over 150 species of birds, more than 20 kinds of mammals, including
four species of monkeys, and hundreds of unique plants, insects, reptiles and amphibians.
To anyone thinking of traveling to the tropics, I highly recommend it. It will open
your eyes to a whole new world.