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OTS offers courses for undergraduate students, graduate
students, professionals and the general public in English, Spanish and
Portuguese. In addition to traditional courses in tropical biology, OTS
also offers courses and training in conservation biology, environmental
policy, and in natural history.
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UPCOMING BIOCURSOS
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Gray-bellied Hawk found at La Selva
The honor of the first recorded sighting of a Gray-bellied Hawk (Accipiter poliogaster) in Costa Rica goes to Octavio Ruiz who found the raptor at the La Selva Biological Station. The image below was taken by Cristian Gamboa. The identification was confirmed by Bill Clark and Sergio Seipke. Congratulations all!
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OTS Unharmed by 6.2 Quake
On Thursday, January 8 Costa Rica was hit by an earthquake registering 6.2 on the Richter scale. Fortunately, none of OTS'
3 biological stations or its office in Costa Rica were affected.
Although the
6.2 magnitude tremor caused major damage around its epicenter (22 miles
northwest of the capital San José , near the Poas Volcano
National Park), no
researchers, students, visitors or local residents were harmed at any of the
stations.
La Selva, Las Cruces and Palo Verde
continue to function normally after the major scare. Access to all stations remains
unaffected. At La Selva Biological Station, 25
kilometers from the epicenter, they felt the tremors but had no direct damage. According to
Deedra McClearn, La Selva Station Director, "Although this station is the closest to
the epicenter, there was no obvious damage.
However, the Sarapiqui River has been drastically changed: it
is now full of mud and debris."  The ecological
impact on this river has been severe and will be
long-lasting. "Members of the staff have taken pictures in the watershed
and Dr. Ron Coleman, a fish biologist from Sacramento State University,
is going to do some post-disaster fish counts", she said.  The powerful earthquake shook the whole
country and killed at least 20 people. More than 200 people were
injured and 42 communities suffered damages. If you have any questions or concerns, please e-mail us at ots@duke.edu. |
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Earthquake Relief Fund
While OTS was not directly affected by the 6.2 earthquake on January 8, the surrounding area was affected greatly. The steep hillside in the region of the La Paz Waterfall collapsed and
about 15 kilometers of steep mountain roads have been destroyed.
There have been approximately 20
deaths so far recorded, but about 18 people are still missing. The number of
homeless or displaced now stands at approximately 2,300 in 23 different
refuges. Rescue and rebuilding efforts are underway but have been suspended
several times because of continuing aftershocks in the area. People who lived
in this area are not being allowed to return yet.
BEFORE AND AFTER PHOTOS from Observatorio Vulcanológico y Sismológico de Costa Rica
The effects of the earthquake were
severe in the area around the epicenter but there has been no widespread loss of
electricity, water, roads, and bridges. Anyone planning travel to Costa
Rica should not be concerned unless they were
planning to be in the Vara Blanca area.
Relief efforts for the local human
population are being coordinated by the Red Cross, National Emergency Commission
of Costa Rica, and the U.S. and Colombian Military (providing helicopter support).
If you would like to help with this
relief effort, please make a contribution to the OTS Earthquake Relief Fund. The La Selva Biological Station is working directly with the Red Cross in the area and Deedra McClearn, La Selva Station Director, is coordinating our support efforts to local agencies providing people with much needed food, water,
housing, and medical supplies. 100% of your donation will be used to support earthquake recovery and relief efforts.
To support this fund, you can:
1. Donate online (please type Earthquake Fund in the comments section)
2. Donate by mail: Please make checks out to OTS and write "Earthquake Fund" in the memo field.
Organization for Tropical Studies
Duke University
410 Swift Avenue
Durham, NC 27705
3. Call 919-684-5774 (United States office) or 506-2524-0607 (Costa Rica office) to make a donation by phone.
Thank you for your help.
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Research on River Conditions Reveals Impact on Fish Species
An interview with Ron Coleman by Deedra McClearn
January 14, 2009
Dr. Ronald M. Coleman is an assistant professor at California State
University, Sacramento.
For the past fourteen years, he has been studying populations of cichlid
fishes in Costa Rica.
He originally focused on the rivers near La Selva but has now examined close to
a hundred rivers in Costa
Rica to compare the parental behavior and
life history of the cichlids in these different rivers. Over the past three years he has also been
monitoring the depth and temperature of the Puerto Viejo
River at La Selva in an
attempt to tie river conditions to the life history of the fishes.
DM: Hi Ron. It's good to see you and your assistants
again. Were you able to retrieve your
river sensors?
RC: Yes, we pulled
the sensors up from the bottom of the river and now have another year's worth
of data to look at.
DM: How do the data
look?
RC: Well, temperature
is not strongly related to depth so we can't use temperature as a proxy for
depth. If the river is deep, it's
cool. But it can also be cool when it's
very shallow. The depth loggers show us
the complicated pattern of floods that happen at La Selva.
DM: How fast can the
river rise?
RC: Twelve meters in
24 hours is about the maximum we have seen for the Puerto Viejo.
DM: I remember you
telling me that the ups and downs of the river levels strongly affect the lives
of the fishes.
RC: For some of the
cichlids I'm studying, the ones with small eggs, the  newly swimming fry can't
withstand fast moving waters until they're about three weeks old. They get swept downstream when they're young
and small. So the breeding season has to
be timed to try to fit the early growth of the fry in with slow and low
water. A long-term change in the pattern
of rains and river levels would definitely affect the populations of many fish
species.
DM: How do the fish
populations look this year?
RC: Up on the Río
Frio, there aren't very many big fish left.
Pressure from local fishing has definitely removed many of the big tuba
(Tomocichla tuba)  and guapote (Parachromis dovii) from that area. This year there have been quite a few young tuba,
so the populations can recover if there is some control of fishing. There are lots of big fish in the La Selva
rivers still so it is very important to protect these stocks. The tuba here are 25% longer and likely twice
the weight of the Río
Frio fish.
Reduced adult size is the first key warning sign of overfishing.
DM: Are La Selva
fishes getting up to the Río Frio? Is La
Selva a source for those populations?
RC: We suspect that
there is limited movement over that kind of distance but the various rivers do
connect as they flow to the Caribbean and it
is conceivable that fish could move. We
are very interested in this issue right now because of the recent earthquake
and subsequent death of the fish of the Río Sarapiquí. Right now, there are still enough adult fish
in the Río Frio to produce the next generations as long as people are careful
about not taking too many fish out of the river. I think people need to be more aware that
it takes years for some of these fish to reach breeding size. Also the guapote are analogous to jaguars,
they are the top predators, and there never were very many to begin with so
they must be carefully conserved.
DM: Are there any
problem fish? Any invasives?
RC: In the last
couple of years, there have been increasing reports of suckermouth catfish (commonly
called "plecostomus") in the Río Sarapiquí.
We haven't seen them at La Selva yet, but it is only a matter of
time. Sadly, this fish, though
interesting in its own right, can be highly detrimental to the local fish
fauna. In the Río Chacamaux, in Chiapas, Mexico,
introduced suckermouth catfish devastated the native fishes.
Also, an ongoing threat comes from tilapia raised for human
consumption. These are increasingly
common in small scale pond aquaculture facilities around Costa Rica, and with flooding, and careless
handling, inevitably some of these get into the local rivers. I have seen them in rivers of the northwest
of Costa Rica and also in
the Río Yatsui, at the southeast border with Panama. I have not seen any here yet. In Nicaragua, they replaced many of
the local fishes.
DM: How has the recent
(Jan 8) earthquake affected the fishes? 
RC: The damage to the Río Sarapiquí was catastrophic. Soil
from landslides completely inundated the river and made it into liquid
mud. There was a massive fish kill -
potentially ALL of the fishes in the Río Sarapiquí at least down to the
confluence with the Río Puerto Viejo may have been killed. We suspect the water went anoxic from all of
the mud and the fish simply died. People
collected them by the thousands along the shores right after the quake. The good news is that Río Puerto Viejo and the Río Sardinal, both important tributaries, were not affected. We are
now hoping to investigate how the fishes recolonize the Sarapiquí from these
other rivers.
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