Table Of ContentA
INTERACTIONS AMONG ATTALE PALMS, BRUCHID BEETLES, AND
NEOTROPICAL TERRESTRIAL FRUIT-EATING MAMMALS: IMPLICATIONS
FOR THE EVOLUTION OF FRUGIVORY
r By
,
KIRSTEN MARIANA SILVIUS
y
A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE
UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE
REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
:
. 1999 •
To Joe,
without whose imagination
creativity
-r determination
bullying
cajoling
loving
laughing
and, of course, canoeing
none of this would have been possible
or even desirable.
ACKNOWLEDGMENTS
Many people contributed to all stages of this
dissertation, and without them both field research and
writing-up would have been very difficult. Two people,
however, provided emotional and logistic support without
which the whole thing might well have been impossible. I am
deeply grateful to Jan Sendzimir and Gisela Bosch for their
friendship and unique definition of human community. Over
the years their support took the form of computers, books,
hot tubs, unending glasses of beer and wine, a dog to walk
and hug, two wonderful daughters to remind me of the other
important things in life, a beautiful wedding celebration
and, most importantly, a temporary place to stay that became
a home to return to even if some day it is transferred to
some other place on this Earth. They are proof that
permanence can come from this impermanent process called
graduate school.
A similar role was played by two members of the World
Doctors (Medecins du Monde) mission to the Yanomami Area in
Brazil. Joseph Ceruetto and Mattieu Lena were incomparable
companions and true friends under difficult circumstances.
They saw the links between the conservation of nature and the
prevention of ethnocide, and provided logistic support for my
research that few others were in a position to provide. They
introduced me to the Yanomami people, their land, and the
indigenists that are struggling to save both, and thus
provided me with the strongest possible motivation to work
for tropical rain forest conservation. The entire World
Doctors team, including the coordinators in France, is to be
commended for its vision and hard work.
Four other people contributed over and beyond the call
of duty to the completion of this dissertation:
My,parents, Robert and Rosita Silvius, were critical to
the endeavor not only by providing their usual rock-solid
trust and encouragement (and strategically placed care
packages), but also by taking care of bureaucratic, financial
and other logistic requirements on the home front while I was
in Brazil.
John Eisenberg enabled the completion of this
dissertation by believing that independence is a good thing
despite the academic risks it carries. During those times
when I felt that maybe I had it all wrong and the data were
not that interesting or valuable, his boundless fascination
with and insight into all things natural rekindled my
enthusiasm for the work. His insight into human nature also
helped me evaluate more clearly the personal and nonacademic
situations that came up while I was writing.
Buzz Rolling contributed more than he can imagine by
providing a different, albeit lumpy, way of thinking about
ecology. His was the most influential of all the classes I
iv
. "
took during my graduate career. He also enabled my escape
from my sixth-floor computerless cubicle by inviting m.e into
the superbly equipped Arthur Marshall lab. Buzz and the
other denizens of 111 Bartram--Lance Garry, Jan, Paul and
,
the irreplaceable Toni Carter--provided advice, inspiration,
technical assistance and a surfeit of Canadian humour.
Without them writing up would have been no fun at all, eh?
I would also like to thank all members of my committee
for providing essential information in the form of
discussions, references and editing. Colin Chapman always
seemed to have the papers I needed. Walter Judd's Tropical
Botany course has stayed with me over the years as a firm
reminder that ecology without taxonomy is an exercise in
futility. Richard Bodmer's focus on the interesting
evolutionary questions my data brought up was refreshing. I
will also always be grateful for his inspired introduction of
a desiccated Mauritia palm fruit at a crucial junction in my
qualifying exams.
The Wildlife Conservation Society provided most of the
funding for my research, and I would like to thank John
Robinson and Alejandro Grajal for supporting a plant-oriented
project. The Lincoln Park Zoo provided additional funding
through the Scott Neotropical Fund. CNPq provided additional
support in the form a visiting researcher fellowship to my
husband, Jose Fragoso, and by granting me permission to carry
out research in Brazil. "
The staff at Maraca Island Ecological Reserve ensured
. .
the smooth running of the station and comfortable living
conditions in a remote place. Station Manager Guttemberg
Moreno de Oliveira did his best to understand the nature of
our research and relied on his love of Maraca to navigate the
political storms that threaten research in places like
Roraima. A consummate humanist, when push came to shove he
always did the right thing for his friends.
vi
TABLE OF CONTENTS
ACKNOWLEDGMENTS iii
ABSTRACT ix
CHAPTERS
,_ ,
1 INTRODUCTION 1
2 PALM FRUITS AND NEOTROPICAL RAIN FOREST MAMMALS: DIRECT
AND INDIRECT RELATIONSHIPS 3
Neotropical Palm Use by Mammals 3
Methods 6
Results and Discussion: Palm-Vertebrate Interactions...8
Results and Discussion: Fruit-Vertebrate-Bruchid
Interactions 17
Summary and Conclusions 29
3 PULP HANDLING BY MAMMALIAN FRUIT-EATERS AFFECTS PALM
SEED PREDATION BY BRUCHID BEETLES 47
Introduction 47
Study Area and Species 51
Methods 55
Results 63
Discussion 71
4 PALM ENDOCARP USE BY THREE NEOTROPICAL SEED-EATERS:
FRUGIVORY OR"GRUBIVORY?" 96
Introduction 96
Study Site 99
Study Species 100
Methods 102
Results 112
Discussion 123
5 AGORUATNIGE(DOANSYMPARROACCTAAIASGLOAUNTDIE)CHOALBOIGTIACTALUSREE,SERDVIEE,T,NAONRDTHHEORMNE
BRAZILIAN AMAZON 141
Introduction 141
MSettuhdoydsArea 1I4453
vii :>
Results 153
Discussion 165
6 SCALE-DEPENDENT DISTRIBUTION PATTERNS IN PLANTS USED
BY THREE TERRESTRIAL RAIN FOREST MAMMALS AT MARACA
ISLAND ECOLOGICAL RESERVE 198
Introduction 198
Study Site 201
Methods 207
Results 211
Discussion 221
7 CONCLUSIONS AND IMPLICATIONS 246
Phenology: Methods and Implications 246
Palm-Mediated Bruchid-Vertebrate Interactions 247
Complexity in Frugivory Systems 248
Mosaics of Fruit Availability: Scale and Grain Size..252
Plant-Animal Interactions and the Aggregated
Distribution of Tropical Forest Plants 255
APPENDICES
1 "EDIBLE" PLANT SPECIES ON PHENOLOGY TRANSECTS 264
2 FLORISTIC PLOT DATA SUMMARIZED FROM MILLIKEN AND
RATTER (1989) AND NASCIMENTO (1994) 266
REFERENCES "\ ,271
.
BIOGRAPHICAL SKETCH 290
viii
.
Abstract of Dissertation Presented to the Graduate School of
the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Doctor of Philosophy
INTERACTIONS AMONG ATTALEA PALMS, BRUCHID BEETLES AND
NEOTROPICAL TERRESTRIAL FRUIT-EATING MAMMALS: IMPLICATIONS
FOR THE EVOLUTION OF FRUGIVORY
BY
Kirsten Mariana Silvius
May 1999 •- '
Chairman: John F. Eisenberg
Major Department: Zoology
The fruits and seeds of arborescent palms are important
food items in the diet of Neotropical terrestrial mammals.
A literature review shows that seventy-seven species of
mammals have been documented feeding on fifty-nine species of
palms. Most of the records are of pulp rather than seed
consumption. Among mammals, terrestrial consumers are the
most important predators and dispersers of palm seeds.
Bruchid beetles (Coleoptera: Bruchidae: Pachymerini) are
specialized predators on palm seeds and are associated almost
exclusively with the coconut-like palms (tribe Cocoeae)
Manipulation of Attalea palm fruits indicated that pulp
removal by rodents, primates, and ungulates improves fruit
quality for ovipositing bruchid beetles. Fruits that fall to
the ground unhandled by any vertebrate have the best chance
ix
of surviving beetle infestation: they are rapidly removed by
tapirs (Tapirus terrestris) and are later defecated at sites
where infestation by bruchids is lov/er than near parent
trees.
Monitoring of palm endocarp use by white-lipped
peccaries (Tavassu pecari), agoutis (Dasvprocta agouti), and
squirrels (Sciurus igniventris) indicates that all three
species feed on bruchid beetle larvae. Squirrels are palm
specialists that feed on both larvae and endosperm year
round; agoutis feed on both larvae and seeds only at times
and at sites where alternate foods are not available; and
white-lipped peccaries feed preferentially on bruchid larvae
rather than seeds. The three species should therefore
respond independently and distinctly rather than as a
community to changes in Attalea fruit availability.
Home range size of five radio-collared agoutis ranged
from 2.9 to 8.5 ha. All animals showed a shift in core area
use as different individuals of the same tree species and
individuals of different tree species came into fruit.
Agoutis responded to their habitat at the scale of individual
trees, and appeared to base foraging decisions on knowledge
of food available on their entire home range. Preferred diet
items were primarily in the Sapotaceae (Pouteria surumuensis
and Pradosia surinamensis) and secondarily in the Palmae
(Astrocaryum aculeatum pulp and seeds and Attalea marioa
pulp)...
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