Volume 14, Number 2
March -April 1997

Director’s Note

There is a tradition in academic institutions
that at approximately seven-year intervals
faculty members may take leave of their
everyday administrative tasks, committee
meetings, teaching assignments and so
forth to concentrate fully on their research
and scholarly work. During this “sabbati-
cal”— a word with the same roots as
“Sabbath”, the seventh day of the week, and
the day of rest — individuals typically
spend from six months to a year pursuing
their own research, be it laboratory, field or
academic in nature. The opportunity to
gain greater depth and broader experience
that the sabbatical provides helps make
them more effective scholars and teachers.

In 1996, three Institute ecologists took
advantage of this opportunity. Dr. David
Strayer was a Visiting Scholar in the
Department of Biological Sciences at Ohio
Northern University, Dr. Richard Ostfeld
was a Visiting Scientist in the Department
of Integrative Biology at the University of
California, Berkeley, and I worked at my
research site in New Hampshire.

The IES Newsletter is published by the
Institute of Ecosystem Studies, located
at the Mary Flagler Cary Arboretum in
Millbrook, New York.

Director: Gene E. Likens

Administrator: Joseph S. Warner

Head of Education: Alan R. Berkowitz
Newsletter editonjill Cadwallader

Address newsletter correspondence to
the editor at:

Institute of Ecosystem Studies
Education Program, Box R

Millbrook NY 12545-0178

or e-mail toJillcad@aol.com

Printing: Central Press, Millbrook, N.Y.

Dr. Likens’ Sabbatical:

Redbacks, Reflection and Research

Hubbard Brook Experimental Forest,
New Hampshire. July 1996, 11 p.m. — It’s
dark and it’s drizzling. Northern redback
salamanders emerge from within and
beneath rotting logs, from under rocks
and from the leaf litter layered on the
forest soil. They climb into shrubs, up
tree trunks, over mosses and across leaf
surfaces, looking for a meal of insects and
other small invertebrates. Suddenly, a
salamander becomes the hunted instead
of the hunter: two rain-jacketed giants
have trapped it in their flashlight beam.
Gene and Phyllis Likens step back and
record the sighting in their field note-
book ...

This research project was one of several
on which Institute of Ecosystem Studies’
Director Likens focused during his recent
sabbatical leave. From May through
November 1996, he spent the bulk of his
time at the Hubbard Brook Experimental
Forest. It was there, in the White Moun-
tains of New Hampshire in 1963, that he
and three colleagues developed a
research program called the Hubbard
Brook Ecosystem Study (HBES). Now, the
Hubbard Brook Experimental Forest is
one of the most intensely studied
landscapes on Earth.

During his seven months away from IES,
Dr. Likens was able to concentrate on his
writing and field work. One of the many
long-term HBES research programs that

he has led is an investigation of the role of
calcium in the forest ecosystem, and one
of his writing projects while on sabbatical
was completion of a monograph called
T he Biogeochemistry of Calciuvi at Hubbard
Brook There were 11 authors, including
Dr. Gary Lovett and Mr. Donald Buso of
IES, and it was Dr. Likens’ challenge to
bring all the contributions together in
one scholarly report. The monograph
now has been submitted for publication.

He also was able to do a great deal of
hands-on field work. In summer 1995 he
began the salamander study, with a focus
on the northern redback salamander
(. Plethodon cinereus), to determine whether
the population of these amphibians at the
Hubbard Brook Experimental Forest has
changed since he and one of his former
Cornell University graduate students did
a similar study 25 years ago. (Dr. Thomas
Burton, now chairman of the Zoology
Department at Michigan State University,
was the student.) Dr. Likens is assisted in
his current work by Phyllis Likens, his
wife. An IES administrative assistant,
Phyllis Likens has been the Hubbard
Brook Ecosystem Study executive
secretary for a number of years. The
purpose of the project is to gather data to
test the idea that there has been a wide-
spread decline in amphibians.

continued on page 3

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L. to r:Dr. F. Sherwood Rowland, Mrs. Phyllis Likens and Dr. GeneE. Likens at the Tyler Environmental
Prize Pavilion Dedication in November. Dr. Likens and Dr. Rowland, who was a 1995 recipient of the Nobel
Prize in Chemistry for his discovery that chlorofluorocarbons could destroy the stratospheric ozone layer, are
past recipients of the Tyler Prize.

The International Appeal of IES: Part II

The Institute of Ecosystem Studies is increasingly a place for international collaboration in research and education. In the last issue of
the IES NEWSLETTER, the cover story introduced visiting scientists from Spain and China. This issue profiles two scientists from
Brazil who are working with IES ecologists for a year.

Limnologist Dr. Vera L.M. Huszar wanted
to work at an institution where she could
improve her research by collaborating
with experts in her field, the study of
freshwater ecosystems. An adjunct
professor of botany at the Universidade
Federal do Rio dejaneiro, Brazil and an
expert on phytoplankton ecology and
taxonomy, Dr. Huszar had become
familiar with the work of IES scientists
through their papers in the scientific
literature. She met Dr. Likens injuly 1995
at the 26th Congress of the International
Association for Theoretical and Applied
Limnology in Sao Paulo where she started
to make plans for her 1997 visit. A fellow-
ship from the Brazilian Government,
which has programs to improve the
qualifications of university professors, is
supporting her work here.

Phytoplankton are microscopic “plants”
suspended in water of lakes and oceans.
They are diverse, found in seven botanical
divisions, or phyla, in three kingdoms
(Monera, Protista and Plantae). In fact,
they are more diverse genetically than all
terrestrial plants combined. This genetic
diversity is associated with a great deal of
diversity in size, growth form, toxicity and
nutrient content. These factors in turn
have an impact on food web transfers,
biogeochemical cycles, aesthetics and

Testing a Model for Algae in Lakes

even, in some cases, human health. Thus,
it is important to understand the environ-
mental conditions that select for different
phytoplankton communities.

Phytoplankton communities in lakes are
extremely variable, depending on
nutrient chemistry, the trophic state, and
physical parameters such as the rate of
water flushing and the frequency of
mixing of the water layers. The Reynolds’
Habitat Template, developed by Dr. Colin
S. Reynolds at the Institute of Freshwater
Ecology in England, is a model that
attempts to explain this variation. The
model considers how algal populations
increase over time, how morphological
and behavioral adaptations are differen-
tially selected and how populations are
assembled. Dr. Huszar’s work at IES is
aimed at testing this model.

Dr. Huszar is working with IES biogeo-
chemist Dr. Nina Caraco, studying
phytoplankton from six lakes ranging
from an oligotrophic, or non-productive,
state, to a eutrophic, or productive, state.
The lakes are: Mirror Lake in the
Hubbard Brook Experimental Forest in
New Hampshire; Ellsworth Pond, near
Hubbard Brook; Lake Wononskopomuc
in Lakeville, Connecticut; and, in New
York, Chodikee Lake, near West Park,

Stissing Lake in Pine Plains, and Mohonk
Lake in New Paltz. For these lakes, many
of the physical and chemical variables
thought to control phytoplankton have
been measured previously as part of work
by Dr. Caraco and Dr. Jonathan Cole on
carbon dioxide and phosphorus dynam-
ics. Samples for measuring these chemical
variables, along with phytoplankton
samples, were collected by IES research
assistants Rich Miller and Peter Raymond.

Dr. Huszar is analyzing the phytoplank-
ton samples from each lake, counting and
identifying the functional groups in
relation to the seasonality and environ-
mental attributes. If the relationship
between the dynamics of the community
and the physical and chemical environ-
mental variability is strong, she hopes to
be able to predict the assemblages of
species and develop approaches for
environmental management.

At home, Dr. Huszar studies phytoplank-
ton ecology in coastal lagoons, in small
reservoirs and in an Amazonian flood-
plain lake that receives tailings from a
bauxite mine. Her work at IES will help
her expand the field of limnology in
Brazil.

What Controls Bacterial Growth in the Hudson River?

Dr. Fabio Roland is an ecologist at thejuiz
De Fora Federal University in the
mountainous Juiz De Fora Province of
Brazil. Also supported by a fellowship
from the Brazilian Government, he is
working with aquatic microbiologist Dr.
Jonathan Cole to learn what environmen-
tal factors control bacterial growth
efficiency in the Hudson River.

Bacteria play an integral role in aquatic
ecosystems. From the point of view of the
carbon cycle, bacteria are catalysts for two
very different kinds of reactions. By the
process of respiration, bacteria oxidize
organic matter, converting it to carbon
dioxide and water. By the process of
growth, bacteria incorporate organic
matter in the environment into their own
tissues. In aquatic ecosystems, the major
pool of organic matter is in the form of
compounds dissolved in the water. This

continued on following page

O
5

InanlES laboratory, Dr. Fabio Roland tests Hudson River water samples to learn more about factors that
affect bacterial growth efficiency.

International Appeal, from page 2

dissolved organic carbon (DOC) is
unavailable to higher organisms, but
bacteria can utilize it. Thus, the portion of
the DOC that goes into bacterial growth
may become available to the consumers of
bacteria (protozoa and small zooplankton)
and this DOC is “recovered” back into the
food web. The portion of the DOC that is
respired by bacteria is lost forever from the
ecosystem. Bacterial growth “links” DOC
to the rest of the food web; bacterial
respiration is a “sink” of this DOC.

Microbial ecologists talk about the
processes of bacterial growth and respira-
tion in terms of bacterial growth effi-
ciency, or BGE. In essence, BGE is the ratio
of bacterial growth to bacterial respira-
tion. If BGE is high, it means that a large
portion of the DOC utilized by bacteria
goes into growth and is therefore available
to the rest of the food web. If BGE is low, it
means that most of the DOC utilized by
bacteria is respired and little is available to
the rest of the food web. While microbial
ecologists routinely measure bacterial

growth, bacterial respiration rarely is
measured. From the studies that exist
(recently reviewed by IES postdoctoral
associate Dr. Paul del Giorgio et al\ see Vol.
13 No. 6 of the IES NEWSLETTER), we do
know that BGE varies widely both among
and within aquatic systems but we do not
yet know the factors that cause BGE to
vary. Dr. Roland is conducting experi-
mental studies of what controls BGE in
the Hudson River.

With IES research assistant David Fischer,
he collects river water samples and
analyzes them for bacterial abundance,
temperature, nutrients and carbon
sources. Results to date show that BGE
decreases with increased bacterial
abundance, increases as the temperature
rises to 25°C (77°F), and drops as the
temperature goes above that. Dr. Roland
will be testing the other parameters in the
coming months.

In his pre- visit correspondence with IES
scientists, Dr. Roland explained that he

would like to learn techniques he could
use to improve microbial ecology
research in Brazil, where he has a limited
budget. In response, Dr. Cole developed
methods that require little in the way of
expensive supplies and scientific instru-
ments. Dr. Roland will be able to use these
methods in the mountain streams of Juiz
De Fora Province, in coastal lagoons and
at Lake Batata in the Brazilian Amazon.

Dr. Rolands work in Brazil also includes
teaching ecology to undergraduate and
graduate students at the university as well
as to primary and secondary school
teachers. While at the Institute, he is
developing ways to integrate teaching and
research, both to give his students a more
complete understanding of the concepts
of ecology and to collect data for his own
research in aquatic ecology. He will be
working with IES ecology educators to
learn about techniques developed and
practiced here that turn the out-of-
doors into a classroom.

Dr. Likens’ Sabbatical, frontpage i

The Likens also worked together on a
forest study in northern Wisconsin. The
forest under investigation had been cut
and burned about 100 years ago and Dr.
Likens is interested to learn more about
ecosystem recovery there. Measurements
included abundance, density and basal
area of all tree species. These data, along
with those collected in 1950, 1960, 1970
and 1980 by forest ecologist Dr. Forest
Stearns, now retired from the University
of Wisconsin, Milwaukee, are being
analyzed and will be published.

In November, Dr. Likens took a short
break from his research and flew to
Canberra, Australia. There, as a member
of a small review committee, he evaluated
the progress of the Cooperative Research
Centre for Freshwater Ecology. “This is
considered one of the top of the [more
than 70] Cooperative Research Centres in
Australia, “ said Dr. Likens upon his
return. “It has an excellent program,
focused on producing the greatest public
good from freshwater ecosystems.”

While in Australia, Dr. Likens —who was
awarded The Australia Prize* in 1994 —
was invited to brief the Minister for the
Environment, Senator the Honorable
Robert Hill, at a dinner at Parliament
House. To an audience comprising
senators, heads of state and federal
agencies and an environmental group, he
spoke on sustainable forestry. This is a

“hot issue” in Australia, due to the many
forest areas that are being cleared for
wood chips used to produce paper and
other wood products in japan.

On the way home, the Likens stopped at
the University of Southern California in
Los Angeles where Dr. Likens partici-
pated in the dedication of the new Tyler
Environmental Prize Pavilion. The Tyler
Prize for Environmental Achievement,
widely considered the “Nobel Prize for
ecology”, is widely recognized as the most
prestigious environmental award in the
world. Dr. Likens and Dr. F. Herbert
Bormann won the 1993 Tyler Prize in
recognition of their pioneering ecologi-
cal research at HBES; other laureates have
included Mr. G. Evelyn Hutchinson, Dr. C.
EverettKoop, Dr. Eugene Odum, Dr. Ruth
Patrick and Dr. Sherwood Rowland. The
new pavilion honors these and the other
31 scientists who have been awarded the
Tyler Prize since its inception in 1974.
Following the dedication, Dr. Likens
spoke on “The Acid Rain Dilemma: Now
and In the Future”, at a conference on

* The Australia Prize is an international
award, sponsored annually by the Australian
Government, in recognition of outstanding
achievement inscienceand technology
promoting human welfare. Dr. Likens xuas
awarded the prize for his work in the field of
sustainable land management.

International Environmental Science,
Policy and Security in the 21st Century.

Dr. Likens’ goals for his sabbatical were to
focus on his research and reserve time to
think, write and interact with colleagues.
The seven months were full and reward-
ing, and he returned to IES satisfied that
he had met these goals.

While Dr. Likens was on sabbatical,
Institute of Ecosystem Studies Scientist
Dr. Michael Pace served as acting
director, dividing his time between
administrative responsibilities at IES and
his research on lake ecosystems.

IES Visitors

The early spring snowstorm brought down
trees and branches across the Mary
Flagler Cary Arboretum.

The IES grounds crew is clearing the
internal roadways first, and then will begin
work on the trails. The Wappinger Creek
and Cary Pines trails will be closed until
they are free of debris and all “widow-
makers” are removed from overhead. The
greenhouse and perennial garden are
open as usual, with a free permit from the
Visitor Center. Call 914/677-5359 for an
update on the status of the trails.

INSTITUTE OF
ECOSYSTEM STUDIES
Education Program
BoxR

Millbrook, New York 12545-0178

Newsletter

Volume 14, Number 2
March -April 1997

CONTINUING EDUCATION
For a Spring 1997 catalogue and program
information, call the Continuing Education
office at 914/677-9643. Programs during May
and June include:

Gardening

May 18: Spring Wildflower Identification
June 21: Designing a Perennial Border for All
Seasons - Section A

June 28: Designing a Perennial Border for All
Seasons - Section B
June 28: Simply Roses

Natural Science Illustration
May 12-17 (daily; call for hours): Pen 8c Ink II
Biology and Earth Science
May 17: Mosses 8c Liverworts: Bryophytes in
the Field

May 31: Ethnobotany of Eastern Woodland
Indians

June 7: Wonderful Weeds: Knowing and
Using the Common Plants of Your Schoolyard

Workshops

May 10: New Cutting-Edge Perennials
May 15: Wetland Creation and Restoration: A
Hands-on Experience

Excursions and Tours

Some of the May andjune trips are filled. At
press time, the following still had openings:

May 30-31: Mt. Cuba, Winterthur and
Bowman’s Hill

May 31: Shawangunks and Ancient Ice Caves
June 14: Bartlett and Highstead Arboreta
June 21: Mohonk Mountain House, Cardens,
Lake and History
June 28: Caprilands Herb Farm

• The Summer 1997 Continuing Education Program
catalogue will be available in early June.

SUNDAY ECOLOGY PROGRAMS
Free public programs are held on the first
Sunday of the month. In May, there will be a
program on the third Sunday as well.

Call 914/677-5359 to confirm the day’s topic or,
in case of poor weather, to learn the status of the
day’s program.

• We recommend that participants wear long pants
tucked into socks and sturdy waterproof shoes for all
outdoor programs.

Nonprofit Org.
US Postage

PAID

Millbrook, NY
Permit No. 16

100 %

Recycled

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Calendar

Sunday Ecology Programs, continued:

May 4: Fish or No Fish: What It Means for Other
Aquatic Organisms in Ponds, led by IES
Research Assistant Dave Thomas
May 18: Super Soil: The World Beneath Our
Feet, led by IES research assistant Alan Lorifice
June 1: Exotic Pests and Forest Health, led by
IES Plant Ecologist Dr. Gary Lovett

IES SEMINARS

Free scientific seminars are held each Friday
through early May, at 3:30 p.m. at the IES
Auditorium:

April 18: Are Continental Shelves “Black
Holes” for Nitrogen. Dr. Sybil Seitzinger, Inst, of
Marine and Coastal Sciences, Rutgers University
April 25: Spatial Projections of Potential
Habitat and Populations of the Gray Wolf and
Implications for Overall Forest Productivity.
Dr. David J. Mladenoff, Department of Forestry,
University of Wisconsin

May 2: Are You Mad as a Hatter? The Environ-
mental Chemistry of Mercury. Dr. Charles T.
Driscoll, Dept, of Civil and Environmental
Engineering, Syracuse University
• The seminar series will resume in September.

VOLUNTEER OPPORTUNITIES

Volunteers are needed in the IES Ecology Shop,
Education Program and Continuing Education
Program offices, library, Perennial Garden and
Fern Glen. For information on volunteering at
IES, call Ms. Su Marcy at 914/677-5359.

IES ECOLOGY SHOP

New in the Shop ...New York maple syrup ... glass
vases in all shapes and colors ... IES photo
notecards ... for children ... new animal finger
puppets ... and in the Plant Room ... flowering
plants ... EZ-diggers ... knee pads ... bird houses
Spring Plant Sale: May 16 and 17 from 10 a.m. -
4 p.m. and May 18 from 11 a.m. - 4 p.m.

Senior Citizens Days: 10% off on Wednesdays
•• Gift Certificates are available ••

GREENHOUSE

The IES greenhouse is open until 3:30 p.m. daily
except public holidays. Admission is by free
permit (see “HOURS”).

HOURS

Winter hours: October 1 - April 30
Closed on public holidays.

Public attractions are open Mon. - Sat., 9 a.m-
4 p.m. & Sun. 1-4 p.m., with a free permit*.

The IES Ecology Shop is open Mon.- Fri., 11a.m.-
4 p.m., Sat. 9 a.m.-4 p.m. & Sun. 1-4 p.m. (The shop
is closed weekdays from 1-1:30 p.m.)

Summer hours begin May 1.

* Free permits are required for visitors and are
available at the IES Ecology Shop or the Education
Program office daily until 3 p.m. (4 p.m. after May 1 ).

MEMBERSHIP

Join the Institute of Ecosystem Studies. Benefits
include subscription to the newsletter, member’s
rate for courses and excursions, a 10% discount
on IES Ecology Shop purchases, and participa-
tion in a reciprocal admissions program.
Individual membership: $30; family member-
ship: $40. Call Ms. Janice Claiborne at 677-5343.

The Institute’s Aldo Leopold Society
In addition to receiving the benefits listed above,
members of The Aldo Leopold Society are
invited guests at spring and fall IES science
updates. Call Ms. Jan Mittan at 677-5343.

TO CONTACT IES...

... for research, graduate opportunities,
library and administration:

Institute of Ecosystem Studies
Box AB

Millbrook NY 12545-0129
Tel: 914/677-5343 • Fax: 914/677-5976
Street address: Plant Science Building,

Route 44A, Millbrook, N.Y.

... for education, general information and the
IES Ecology Shop:

Institute of Ecosystem Studies
Education Program, Box R
Millbrook NY 12545-0178
Tel: 914/677-5359 • Fax: 914/677-6455
Street address: Gifford House Visitor and
Education Center, Route 44A, Millbrook, N.Y.

IES e-mail: cacw@vm.marist.edu

IES home page: http://www.marist.edu/~ies