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Foraging behaviour of the Brazilian squirrel Sciurus aestuans (Rodentia, Sciuridae)

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We describe the foraging behaviour of the Brazilian squirrelSciurus aestuans Linnaeus, 1776 in a natural free-living population, in an area with a high concentration of palm fruitsSyagrus romanzoffiana (Chamisso) Glassman. Our objective was to investigate if the abundance ofS. romanzoffiana fruits, an important food item for squirrels, temporally influenced the foraging behaviour of this population. The observations were carried out over an eight-month (April–November 2001) period. Fruiting phenology ofS. romanzoffiana was also monitored. The most consumed food item for this period was the fruit ofS. romanzoffiana (70%), followed by foods of human origin (14%). The percentage of time spent feeding increased in September, and the time spent travelling declined in September, October and November, when females were observed showing evidence of reproductive activity. At the same timeS. romanzoffiana fruits become available. The consumption of human items illustrates the opportunistic feeding habit of these squirrels, but variations in foraging behaviour detected probably were more strongly related to availability ofS. romanzoffiana fruits.
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Introduction
Al though op por tu nis tic and gen er a list in
their feed ing hab its, squir rels feed pri mar ily on
fruits and seeds. Fruit pro duc tion nor mally
var ies ac cord ing to spe cies, lo ca tion and year,
and this may in flu ence the num ber of an i mals in
a pop u la tion, as well as their dis tri bu tion in
dif fer ent for ested hab i tats (Gurnell 1996). Be -
sides, dif fer ences in food avail abil ity and qual ity
be tween hab i tats may ex plain vari a tions in the
ac tiv ity pat tern and for ag ing be hav iour of squir -
rels (Wauters et al. 1992). Ar eas with poor food
sup plies are avoided by squir rels, which in stead
con cen trate their ac tiv i ties in hab i tats with
more abun dant food re sources (Lurz et al. 2000).
In this study, we in ves ti gated the for ag ing
be hav iour of a pop u la tion of Sciurus aestuans
Linnaeus, 1776, in a sec ond-growth for est in the
Serra do Caraça Re serve, in which there is a
high con cen tra tion of the palm Syagrus roman-
zoffiana (Arecaceae). Some stud ies in di cated
that the fruits of this palm tree were an im -
[69]
Acta Theriologica 51 (1): 69–74, 2006.
PL ISSN 0001–7051
For ag ing be hav iour of the Bra zil ian squir rel Sciurus aestuans
(Rodentia, Sciuridae)
Cibele A. ALVARENGA and Sônia A. TALAMONI
Alvarenga C. A. and Talamoni S. A. 2006. For ag ing behaviour of the squir rel Sciurus aestuans
(Rodentia, Sciuridae). Acta Theriologica 51: 69–74.
We de scribe the for ag ing behaviour of the Bra zil ian squir rel Sciurus aes-
tuans Linnaeus, 1776 in a nat u ral free-liv ing pop u la tion, in an area with a
high con cen tra tion of palm fruits Syagrus romanzoffiana (Chamisso) Glassman.
Our ob jec tive was to in ves ti gate if the abun dance of S. romanzoffiana fruits,
an im por tant food item for squir rels, tem po rally in flu enced the for ag ing
behaviour of this pop u la tion. The ob ser va tions were car ried out over an
eight-month (April–No vem ber 2001) pe riod. Fruit ing phenology of S. roman-
zoffiana was also mon i tored. The most con sumed food item for this pe riod was
the fruit of S. romanzoffiana (70%), fol lowed by foods of hu man or i gin (14%).
The per cent age of time spent feed ing in creased in Sep tem ber, and the time
spent trav el ling de clined in Sep tem ber, Oc to ber and No vem ber, when fe males
were ob served show ing ev i dence of re pro duc tive ac tiv ity. At the same time
S. romanzoffiana fruits be come avail able. The con sump tion of human items
il lus trates the op por tu nis tic feed ing habit of these squir rels, but vari a tions in
for ag ing behaviour de tected prob a bly were more strongly re lated to avail -
abil ity of S. romanzoffiana fruits.
Post-graduate Programme in Vertebrate Zoology. Pontifícia Universidade Católica de Minas
Gerais. Av. Dom José Gaspar, 500, Belo Horizonte, MG, 30535-610, Brazil,
e-mail: cibele_alvarenga@yahoo.com.br, talamoni@pucminas.br
Key words: Sciurus aestuans, Syagrus romanzoffiana, for ag ing be hav iour
por tant food re source for this spe cies (Galetti et
al. 1992, Paschoal and Galetti 1995, Bordignon
and Monteiro Filho 1999, 2000). Thus, the high
avail abil ity of this fruit in the area of study
al lowed us to in ves ti gate if the abun dance of
pre ferred food tem po rally af fected for ag ing be -
hav iour of this free-living population.
Methods
The study was con ducted in the Serra do Caraça Pri vate
Nat u ral Her i tage Re serve (20°05’S, 43°29’W), lo cated on the
slopes of the Serra do Espinhaço Moun tains sys tem, in a
re gion con sid ered to be a tran si tion zone be tween the
Cerrado and the At lan tic For est biomes, in the state of
Minas Gerais, Brazil. The Re serve mea sures 10 187 ha,
with el e va tion rang ing from 850 to 2070 m a.s.l. and a
cli mate marked by a rainy sum mer (Oc to ber March) and a
dry win ters (AprilSep tem ber). Var i ous floristic for ma tions
char ac ter ize the Re serve and in clude semideciduous for ests,
high-al ti tude fields, and rupestrian fields (grass lands sur -
rounded by rock out crops, as well as shrubs and small trees).
The study was car ried out in sec ond-growth for est lo -
cated near the Re serve’s head quar ters, and in a gar den
around the head quar ters where there are other ex otic tree
spe cies, such as Cupressus (20–30 trees, Cupressaceae) and
Quercus sp. (5 trees, Fagaceae). In the study area tour ists
are con stantly pres ent and food of hu man or i gin (bread,
pop corn, bis cuits, cake, pea nuts, ba nanas) is fre quently
sup plied to the an i mals. From April to No vem ber 2001, for -
ag ing be hav iour of squir rels was in ves ti gated at nine ob ser -
va tion points, en com pass ing an area of 4.0 ha. In each
month a set route for mak ing ob ser va tions was trav eled
dur ing 6 days to en sure that all nine points were sam pled
at all times of the day. Observations were made us ing 8–17
´ 25 mm bin oc u lars be tween 6:00 to 18:00 hours. Thirty
min utes were spent at each ob ser va tion point, dur ing which
fo cal-an i mal sam pling with con tin u ous re cords, and mod i -
fied scan sam pling were car ried out (Altmann 1974). The
thirty-min ute pe riod was di vided into five ini tial min utes of
scan sam pling, twenty min utes of fo cal-an i mal sam pling
and the last five min utes again of scan sam pling. Time al lo -
cated to each be hav iour cat e gory was quan ti fied us ing data
ob tained from fo cal-an i mal sam pling. Data from scan sam -
pling was ex pressed as the to tal num ber of oc cur rences of
the dif fer ent be hav iour cat e go ries (Mar tin and Bateson
1986). In each month, ob ser va tion time to taled 60 hours.
Af ter pre lim i nary ob ser va tions, five be hav iour cat e go ries
were re corded as shown in the ethogram be low: Trav el ing
walk ing or run ning in trees or on the ground; Feed ing – con -
sump tion of food, in clud ing food han dling prior to eat ing,
and drink ing of wa ter; Search ing for food – in trees or on
the ground; Rest ing sit ting or ly ing on a tree branch, or
stand ing still on the ground; Other be hav iours – Food
caching, food retrieval, grooming, vocalizing, nest building,
agonistic interactions.
The be hav ioural ob ser va tions were car ried out on 15
squir rels (8 fe males and 7 males) pre vi ously trapped and
marked be tween Feb ru ary and April 2001, and three non
marked squir rels, who were iden ti fi able from in di vid ual
marks (ie, one fe male who had a big white spot on her right
leg; one male with out a right fore foot and blind in one eye;
and an other male with a torn ear). These squir rels were
in cluded in our data col lec tion be cause they were fre quently
ob served in the months af ter the cap ture of the marked an i -
mals. The cap ture was done us ing 12 live-traps (gal va nized
wire cages mea sur ing 15 ´ 15 ´ 32 cm) in the study area.
S. romanzoffiana fruits or pea nuts were used as bait. In di -
vid u als were marked us ing plas tic col lars with two col ored
beads: one color for sex iden ti fi ca tion and the other for
in di vid ual iden ti fi ca tion. The mark ing and re lease of the
squir rels oc curred im me di ately af ter cap tures.
The phenology of S. romanzoffiana was an a lyzed ev ery
two weeks. Al to gether, 105 trees dis trib uted in the ob ser va -
tion area were in di vid u ally marked. The num ber of ripe
fruit bunches, im ma ture fruit bunches and flow ers in each
tree were re corded. To cal cu late the avail abil ity of fruit, an
av er age of 796.5 ± 331.6 fruits (n = 20, Galetti et al. 1992)
per bunch was mul ti plied by the num ber of ob served ripe
fruit bunches.
Spearman’s rank cor re la tion (Zar 1999) was used to test
the hy poth e sis that time spent by squir rels in the dif fer ent
be hav iour cat e go ries and num ber of oc cur rences of each cat e -
gory may be as so ci ated with avail abil ity of S. romanzoffia-
na fruits. Also in ves ti gated was whether fruit con sump tion
cor re lated with the es ti mated avail abil ity of S. romanzoffia-
na fruits in the study area.
Results
Feeding and trav el ing had the great est per -
cent ages of oc cur rence us ing both fo cal-an i mal
sam pling (Fig. 1) and scan sam pling (Fig. 2). The
most in fre quent be hav iours were search ing for
food and rest ing (Figs 1 and 2). Feeding in creased
in the month of Sep tem ber, while trav el ing
de clined in Sep tem ber, Oc to ber and No vem ber,
when com pared with pre vi ous months (Fig. 1).
At the be gin ning of the study, most of the
an i mals ob served were sub-adults. Fe males
show ing ev i dence of re pro duc tive ac tiv ity (eg,
large nip ples and lac ta tion) were ob served in
Sep tem ber and Oc to ber. Dur ing this time, three
new fe males with signs of re pro duc tive ac tiv ity
ap peared in study area; whereas, a to tal of 2
males dis ap peared, one in June and one in
July, re spec tively. Fur ther more, 2 new ju ve nile
squir rels were ob served in the study area in
No vem ber, at the end of the study.
70 C. A. Alvarenga and S. A. Talamoni
The food most of ten con sumed by the squir -
rels was the fruit of S. romanzoffiana, to tal ing
70.7% of the to tal food con sump tion (Ta ble 1).
Food of hu man or i gin was also eaten by squir rels,
and rep re sented 14.1% of to tal food con sump tion.
S. romanzoffiana fruits were con sumed most
of ten in the month of April, when 57 oc cur rences
of squir rels feed ing on these fruits were re corded,
af ter which the num ber of oc cur rences was vari -
able. In No vem ber, 66 oc cur rences of squir rels
feed ing on dif fer ent food types were ob served
(Ta ble 1). Phenological anal y sis of S. roman-
zoffiana showed that avail able ripe fruits in the
trees were in creas ing from 796.5 (1 bunch), 2389
(3 bunches), 3186 (4 bunches) and 3982 (5
bunches) for the months of Au gust, Sep tem ber,
October and November, respectively.
Squir rels were se lec tive in their con sump tion
of S. romanzoffiana fruits; they would eat some
and dis card oth ers. Squir rels re quired 220.2 sec
± 84.6 (mean ± SD; n = 48) to re move the exocarp,
open the endocarp and eat the en do sperm. One
young squir rel, ob served in No vem ber, spent
al most one hour on this pro cess. The act of
cach ing fruit of S. romanzoffiana, bread and
pea nuts be tween rocks, un der leaves, fallen
trunks, or in side bro meli ad (Aechmea blanche-
tiana), or bury ing S. romanzoffiana fruit in
sand, was ob served 27 times dur ing the study.
An adult squir rel was seen re cov er ing S. roman-
Foraging of Brazilian squirrel 71
0
20
40
60
80
Feeding
Travelling
Searching for food
Resting
Oct Nov
Aug Sep
Apr May Jun Jul
Behaviour categories (%)
Fig. 1. Per cent ages of time al lo cated for be hav iour cat e go ries ob served for Bra zil ian squir rels, Sciurus aestuans, in the Serra
do Caraça Re serve dur ing April to No vem ber 2001. Data ob tained by fo cal-an i mal sam pling.
Feeding
Travelling
Searching for food
Resting
0
20
40
60
80
Behaviour categories (%)
Oct Nov
Aug Sep
Apr May Jun Jul
Fig. 2. Per cent ages of oc cur rences of be hav iour cat e go ries ob served for Bra zil ian squir rels, Sciurus aestuans, in the Serra do
Caraça Re serve dur ing April to No vem ber 2001. Data ob tained by scan sam pling.
zoffiana fruit from the ground and cach ing
them, one by one, at a dis tance of ap prox i mately
3 m from the tree. Twelve fruits were cached in
11 min utes.
Ex cept for an in verse cor re la tion be tween the
per cent age of time spent search ing for food and
the con sump tion of hu man items (r
s
= –0.85, p =
0.007), Spearman’s rank cor re la tions showed no
sig nif i cant re la tion ship be tween the main be -
hav iour cat e go ries ob tained by both sam pling
types and the con sump tion of S. romanzoffiana
fruit (p > 0.05). A sig nif i cant neg a tive cor re -
la tion was ob served be tween the con sump tion of
S. romanzoffiana fruits and the con sump tion of
anthropic items (r
s
= –0.73, p = 0.037). The
num ber of oc cur rences of the cat e gory feed ing
cor re lated pos i tively with the avail abil ity of S.
romanzoffiana fruits (r
s
= 0.74, p = 0.05).
Discussion
Lac tat ing fe males were cap tured in Sep tem -
ber and Oc to ber, so the young must have been
born around this time. Young ap pear to be
in de pend ent at the same time that fruit of
S. ro manzoffiana be come avail able. Dur ing our
study, some males moved out of the study area
dur ing the re pro duc tive pe riod and never re -
turned. Con versely, non-res i dent lac tat ing fe -
males were re corded in the study area only in
the fi nal months of the study, when we ob served
the great est abun dance of food. These facts may
be due to be hav ioural dif fer ences be tween the
sexes, with males tend ing to travel lon ger dis -
tances to find re cep tive fe males for mat ing and
fe males look ing for ar eas with more abun dant
food sup plies to meet their en ergy needs dur ing
72 C. A. Alvarenga and S. A. Talamoni
Ta ble 1. Oc cur rences and per cent ages (in brack ets) of Bra zil ian squir rels, Sciurus aestuans, ob served feed ing on the dif fer ent
food items, in the Serra do Caraça Re serve dur ing April to No vem ber 2001. Data ob tained by scan sampling.
Food item
Apr May Jun Jul Aug Sep Oct Nov Total
Syagrus romanzoffiana 57 (93.4) 36 (66.7) 25 (61.0) 28 (52.8) 26 (74.3) 23 (82.1) 43 (84.3) 37 (56.1) 275 (70.7)
fruit (Palmae)
Lafoensia pacari fruit 1 (1.6) 3 (5.6) 6 (14.6) 11 (20.8) 1 (2.0) 22 (5.7)
(Lythraceae)
Cupressus fruit 2 (4.9) 3 (5.7) 1 (3.6) 1 (1.5) 7 (1.8)
(Cupressaceae)
Bark 1 (1.9) 1 (2.9) 3 (5.9) 1 (1.5) 6 (1.5)
Rubus brasiliensis fruit 1 (1.6) 2 (3.7) 1 (1.9) 1 (2.0) 5 (1.3)
(Moraceae)
Musa fruit 2 (5.7) 2 (7.1) 4 (1.0)
(Musaceae)
Dasyphyllum fruit 3 (5.7) 3 (0.8)
(Asteraceae)
Salacia brachypoda 3 (4.5) 3 (0.8)
flower (Lauraceae)
Psidium guajava fruit 1 (1.6) 1 (1.9) 2 (0.5)
(Myrtaceae)
Moss 1 (1.6) 1 (1.5) 2 (0.5)
Prunus persica fruit 2 (3.0) 2 (0.5)
(Rosaceae)
Myrciaria delicatua 2 (3.0) 2 (0.5)
fruit (Myrtaceae)
Lichen 1 (1.5) 1 (0.3)
Anthropogenic items 11 (20.4) 8 (19.5) 7 (13.2) 6 (17.1) 2 (7.1) 3 (5.9) 18 (27.3) 55 (14.1)
Total 61 (100) 54 (100) 41 (100) 53 (100) 35 (100) 28 (100) 51 (100) 66 (100) 389 (100)
lac ta tion (Wauters and Dhondt 1992, Andrén
and Delin 1994, Lurz et al. 2000, Ro dri guez and
Andrén 1999). In the area stud ied, sev eral nests
were found near food re sources (Alvarenga 2002),
thus nurs ing fe males would not have to search
for food in other ar eas and could thus spend less
time away from their young.
Ac cord ing to Gurnell (1996), re pro duc tive
suc cess of Sciurus carolinensis Gmelim, 1788 fe -
males cor re late pos i tively with the avail abil ity
of food in the area. Wauters and Dhondt (1989),
in a study of the red squir rel Sciurus vulgaris
Linnaeus, 1758, re ported that lac tat ing fe males
have to ad just their for ag ing hab its, ac tiv ity pat -
tern and nest uti li za tion, be cause they can not
leave the nest to search for food, to meet their
en ergy re quire ments dur ing lac ta tion. Thus, the
abun dance of fruit of S. romanzoffiana, the main
food re source in the area, as so ci ated with the
prob a ble birth of young, may ex plain the in -
creased time spent feed ing and the de cline in the
time spent mov ing around in the months of Sep -
tem ber, Oc to ber and No vem ber. Our data sug -
gest that lac tat ing fe males can op ti mize their
time spent feed ing by se lect ing hab i tats with
greater food avail abil ity, thereby reducing the
need to spend time traveling in search of food.
Phenological anal y sis of S. romanzoffiana
in di cated that the fruits of this palm tree were
avail able from Au gust to No vem ber, yet were
con sumed dur ing all months be cause of the food
cach ing habit of squir rels. The cach ing and
dis card ing of fruit, of ten ob served in our study,
sug gests that squir rels ef fi ciently dis perse S.
romanzoffiana as re ported for S. aestuans (Maia
et al. 1987, Galetti et al. 1992, Paschoal and
Galetti 1995, Bordignon and Monteiro Filho
1999). Sev eral seed lings were ob served at a
dis tance from the mother-tree, sug gest ing that
dis persal had oc curred. How ever, re search is
needed to de ter mine the ac tual role played by
squir rels as agents of dis persal of this tree
spe cies in the area. Quercus fruit is usu ally con -
sumed by squir rels in the north ern hemi sphere
(Koprowski 1994, Gurnell 1996), how ever the
trees that oc cur in the study area had not
developed fruits for a long time.
The ab sence of sta tis ti cal sig nif i cance be -
tween feed ing oc cur rences and the avail abil ity
of fruit of S. romanzoffiana is prob a bly due to
the fact that the abun dance of fallen and cached
fruits, and the quan tity of anthropogenic foods,
the sec ond most im por tant food re source in the
Re serve, were not eval u ated. The neg a tive as -
so ci a tion be tween the con sump tion of fruit of
S. romanzoffiana and the con sump tion of an-
thropogenic food, to gether with the neg a tive
cor re la tion be tween the time spent search ing for
food and the con sump tion of anthropogenic
items, pro vides fur ther ev i dence of the op -
por tu nis tic feed ing hab its of these an i mals.
How ever, the vari a tions in for ag ing be hav iour of
squir rels prob a bly re flect avail abil ity of fruits of
S. romanzoffiana.
Ac knowl edge ments: We thank J. L. Koprowski and two
anon y mous re view ers for help ful com ments. To R. J. Young
and A. Linghorn for manu script re vi sion. The Caraça Re -
serve Staff pro vided us with all fa cil i ties to com plete our
study. FIP PUC Minas pro vided fi nan cial sup port.
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Foraging of Brazilian squirrel 73
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Associate Editor was Joseph F. Merritt.
74 C. A. Alvarenga and S. A. Talamoni
... In this way, the relation resource-consumer may be a good way to understand the role of biotic interactions in species distributions; furthermore, this relation was recorded as necessary additional information for the knowledge of the role of biotic interactions in SDMs (Anderson 2017). Herein we used a food specialist species of squirrel to predict its actual distribution once its distribution is poorly known in Brazil, but its foraging behavior is marked by the strong interaction with a palm tree fruit (Alvarenga and Talamoni 2006). ...
... In spite of the generalism in squirrels' diet, in the Brazilian Atlantic Forest, the foraging behavior of S. aestuans is characterized by the use of the fruit of Syagrus romanzoffiana (Cham.) Glassman (Paschoal and Galetti 1995;Bordignon and Monteiro-Filho 2000;Alvarenga and Talamoni 2006). In a study developed in the Brazilian Atlantic Forest, S. romanzoffiana presented up to 70% of S. aestuans diet (Alvarenga and Talamoni 2006). ...
... Glassman (Paschoal and Galetti 1995;Bordignon and Monteiro-Filho 2000;Alvarenga and Talamoni 2006). In a study developed in the Brazilian Atlantic Forest, S. romanzoffiana presented up to 70% of S. aestuans diet (Alvarenga and Talamoni 2006). The same study shows that the palm tree is essential for the reproduction of squirrels, where lactating females spend their time feeding and not searching for food, suggesting elevated habitat fidelity near the palm tree (Alvarenga and Talamoni 2006). ...
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Species distribution models are not usually calibrated with biotic predictors. Our study question is: does the use of biotic predictors matter in predicting species distribution? We aim to assess the importance of biotic predictors in the output of distribution models of the Brazilian squirrel ( Sciurus aestuans ) throughout South America based on fruits of Syagrus romanzoffiana – the most consumed food resource. We hypothesized that the distribution model of S. aestuans using its main food resource as a biotic predictor will be more accurate in comparison with the output of the model without the biotic predictor. We built three different distribution models: (i) distribution of S. romanzoffiana ; (ii) distribution of S. aestuans without biotic predictor; and (iii) distribution of S. aestuans with biotic predictor. We evaluated performance scores, number of presence pixels and concordance between suitability maps. We found that performance scores may not vary between models with different predictors, but the output map changed significantly. We also found that models with biotic predictors seem to vary less in presence pixels. Furthermore, the main variable in the distribution model was the biotic variable. We conclude that the knowledge of a species’ biology and ecology can make better predictions of species distribution models mainly by avoiding commission errors.
... The pulp and kernel are the fruit parts that are most likely to be used by humans (Goudel 2012). Its fruits are also consumed by various animals, such as Tupinambis merianae, including a number of mammals, such as Sciurus ingrami, Cerdocyon thous, Tapirus terrestris, Cebus apella, Alouatta guariba, and Alouatta fusca (Fleury 2003;Alvarenga and Talamoni 2006). The leaves provide forage for livestock, smashed and broken kernels serve as food for birds, and large peduncular bracts are used in crafts and decorations (Noblick 2017). ...
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Fruits of the Brazilian Cerrado: Composition and Functional Benefits describes the nutritional, chemical and physical characteristics of the fruits of the Cerrado, as well as their pharmacological effects and use in phytotherapics. Chapters are dedicated to the morphological characteristics, macronutrients, micronutrients and active compounds of various fruits, with separate sections covering their peels, leaves, nuts, pulps, and other components. The text also includes detailed studies on the treatment of diseases with these natural products, as well as their applications in popular use by local communities. Authors explain the importance of bioactive compounds found in the fruits and their possible mechanisms of action in the organism. This text thus provides a valuable reference to researchers studying a range of topics, including functional foods, phytotherapy, and plant science.
... The pulp and kernel are the fruit parts that are most likely to be used by humans (Goudel 2012). Its fruits are also consumed by various animals, such as Tupinambis merianae, including a number of mammals, such as Sciurus ingrami, Cerdocyon thous, Tapirus terrestris, Cebus apella, Alouatta guariba, and Alouatta fusca (Fleury 2003;Alvarenga and Talamoni 2006). The leaves provide forage for livestock, smashed and broken kernels serve as food for birds, and large peduncular bracts are used in crafts and decorations (Noblick 2017). ...
Chapter
Acrocomia aculeata contains various phytochemicals that contribute to the health benefits, and the consumption of both pulp and kernel is very popular in the Brazilian Cerrado region. Although a lot of research has been conducted, none review of the literature about health benefits of Acrocomia aculeata and its phytochemicals has been compiled. In this sense, this chapter aimed to present the results of studies carried out on the species in traditional application, phytochemicals, health benefits and toxicology of the fruit, kernel and leaves of A. aculeata. The main phytochemicals found in pulp, kernel and leaves are rutin, quercetin and tocopherols. These common phytochemicals are responsible for health effects such as: anti-inflammatory, antioxidant and antimicrobial, hypolipidemic and diuretic effects. Moreover, toxicological studies have been explored to evaluate the safety of parts of the plant that are commonly consumed and provide information on benefits and uses. This work compiles several useful reports for researchers interested in biological activity and main uses of A. aculeata.
... The pulp and kernel are the fruit parts that are most likely to be used by humans (Goudel 2012). Its fruits are also consumed by various animals, such as Tupinambis merianae, including a number of mammals, such as Sciurus ingrami, Cerdocyon thous, Tapirus terrestris, Cebus apella, Alouatta guariba, and Alouatta fusca (Fleury 2003;Alvarenga and Talamoni 2006). The leaves provide forage for livestock, smashed and broken kernels serve as food for birds, and large peduncular bracts are used in crafts and decorations (Noblick 2017). ...
Chapter
The Caryocar spp. plants are well known in Brazil, especially for inhabitants of Cerrado biome, commonly called as Pequi, Piqui or Piquiá. The fruit is a typical and characteristic fruit of the midwest region, being appreciated in the traditional cuisine, especially because of their “exotic” flavor and unique manner to consume it, due to its thorny endocarp. Due to its traditional use, mainly as food, nutraceutical, or as medicine, the whole plant has been paid attention to by the scientific community. Thus, considering the high potential of the plant, especially pulp and almond fruit parts, this chapter presents a wide introduction about the chemical composition, food properties and a large biological properties identified by several studies, mainly in the last decades. The fruit presents excellent properties as food, being a satisfactory source of proteins, lipids, carbohydrates and minerals. The fatty acids content varies including the saturated palmitic acid, monounsaturated oleic acid and polyunsaturated arachidonic acid. Besides, several bioactive compounds were identified such as carotenoids; phenolic compounds, including flavonoids; α-tocopherol and tannins. The Caryocar spp. plants have shown interesting biological action for several purposes, i.e., as anti-inflammatory, dermatological, anti-microbiological, gastroprotection, hepatic, vascular and cardioprotection as well as anticancer and antigenotoxicity properties, being a promising ally to human health.
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Present three year-long (2016 to 2019) study deals with the spatio-temporal distribution pattern of Ratufa indica, the endemic giant squirrel of India inhabiting Kuldiha Wildlife Sanctuary. The dietary preferences, behavioural attributes including different reproductive aspects and effect of forest phenology on breeding cycle of the species were documented. Results depicted that sighting frequency (23±0.7 per hour) of this canopy dweller was highest during pre-monsoon morning near forest personnel's residence (Site I). In monsoon and post-monsoon, they preferred to inhabit the denser parts of the forest (Sites II and III). Maximum occurrence and activities were observed at upper canopy layer (56%) during pre-monsoon, whereas, during late monsoon and early post-monsoon, they were observed to come down more frequently to the ground level (27% and 17% respectively). Forest phenology was noted to synchronize with the breeding cycle of this frugivorous rodent. Reproductive cycle was observed to be biannual via two breeding phases: the pre-monsoon and the post-monsoon; with the attainment of maximum litter size (3) during the former. Being an effective functional operator of forest ecology, maintenance of canopy contiguity coupled with the presence of juicy fruit-bearing plants turned out to be essential for this flagship ani-mal's conservation strategy against the prevailing threat factors.
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Cocoa is a strategic resource because it hosts high biodiversity, and it is a reliable source of foreign exchange. In Venezuela, fungi and red squirrels mainly affect its productivity. The objective was to evaluate the influence of the cocoa crop structure on the level of damage caused by red squirrels on the pods. The vegetation structure was defined in 15 farms assessing the cocoa tree biomass, the magnitude of shade tree cover, number of associated crops, presence of alternative fruit trees, and the type of ecological succession present in the surrounding. The % of damage was calculated, and nonparametric tests were used to process data. The damage was higher in crops with less shade cover, a more abundant number of associated crops, and alternative fruit trees. Squirrels used the cocoa pods opportunistically but preferred other fruits. It is concluded that pods can be a complementary food for squirrels to the extent that the cocoa plantation is more complex and has a connection with the forest. Shade cover did not directly influenced squirrels, but it is crucial for bird predators which are more sensitive to disturbance.
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Background and Aims Psidium is the 4th largest genus of Myrtaceae in the Neotropics. Psidium guajava is widely cultivated in the tropics for its edible fruit. It is commercially under threat due to the disease guava decline. P. cattleyanum is one of the 100 most invasive organisms in the world. Knowledge of the phylogenetic relationships within Psidium is poor. We aim to provide a review of the biology, morphology and ecology of Psidium, a phylogenetic tree, an infra-generic classification and a list of species. Methods Morphological and geographic data were obtained by studying Psidium in herbaria and in the field between 1988 and 2020. Forty-six herbaria were visited personally. A database of c. 6,000 specimens was constructed, and the literature was reviewed. Thirty species (c. 1/3 of the species in the genus) were sampled for molecular phylogenetic inference. Two chloroplast (psbA-trnH and ndhF) and two nuclear (ETS and ITS) regions were targeted. Phylogenetic trees were constructed using Maximum Likelihood (ML; RaxML) and Bayesian Inference (BI; MrBayes). Key Results Psidium is a monophyletic genus with four major clades recognized as sections. Section Psidium (ten species), to which P. guajava belongs, is sister to the rest of the genus; it is widespread across the Neotropics. Section Obversifolia (six species; restricted to the Brazilian Atlantic Forest), which includes P. cattleyanum, is sister to the innermost clade composed of sister sections Apertiflora (31 species; widespread but most diverse in the Brazilian Atlantic Forest) + Mitranthes (26 species; widespread in dry forests and probably diverse in the Caribbean). Characters associated to diversification within Psidium are discussed. Conclusions Research on prefoliation, colleters, leaf anatomy, leaf physiology, staminal development, placentation, and germination associated to the anatomy of the opercular plug is desirable. Studies are biased towards sections Psidium and Obversifolia, with other sections poorly known.
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Cocoa is a tropical crop of great economic and ecological importance, with great potential in Venezuela, where fungal diseases and squirrels, among other factors, affect its productivity. The objective of the work was to analyze the relationship between the level of damage and some agronomic and environmental variables in 39 production of the state of Merida. The types of cocoa present were classified as criollo, forastero and hybrid. The damage percentages were transformed to arcsine and grouped into subjective categories according to the variables; the relationship was statistically analyzed using non-parametric tests: Kruskal-Wallis, Kolmogorov-Smirnov, and Moses, assuming = 0.05. The level of damage was not statistically different (p> 0.05) between the crops located at different altitudes. The same occurred with the variables cocoa lot size, planting density, number of cultivars, level of agrochemicals, type of vegetation surrounding the crop, and distance to the forest. But the level of damage was statistically different (p 0.05) between the production units that differed in the number of associated crops. The level of damage was also statistically different according to the number of shade trees.ha-1 and among those that differed with respect to the presence/absence of alternative fruits. It is concluded that the structural complexity of the crops functions as an integrating element in determining the level of damage caused by squirrels and defines the suitability of their habitat.
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Palm trees belong to the family Arecaceae and are often considered an ecologically relevant species, since they present low fructification synchrony and represent, in times of food scarcity, an important source of resources for the fauna. This family is formed by several genera and species, including Syagrus romanzoffiana (Cham.) Glassman., which is a palm tree found in several countries, but endemic in South America. In Brazil, it is spread from North to South, through almost all vegetable formations, including the Cerrado. Although it is a fruit tree with great agricultural potential, its use in food is more restricted to consumption of the fruits in natura. The Syagrus romanzoffiana fruit has a very fibrous and orange colored pulp, due to the presence of carotenoids. It can be used to treat diseases of the digestive and renal systems. The kernel is rich in oil predominantly composed of saturated fatty acids and, consequently, of high oxidative stability. Thus, the purpose of this chapter is to collect information available on Syagrus romanzoffiana, covering various aspects of the plant, mainly the fruit pulp and kernel and their possible nutritional, biological, and pharmacological applications, in order to disseminate the importance of this species.
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A population of Eurasian red squirrels (Sciurus vulgaris) in south-central Sweden showed a strong preference for forest older than 35 years and with more than 25% Norway spruce (Picea abies). This preferred habitat constituted 24% of the study area. The proportion of avoided habitats was 30%, and the remaining 46% could be described as used but not preferred habitats. Given these proportions, the squirrels can be shown theoretically to be able to reach all preferred patches by moving across the used, although not preferred habitat patches, or within the preferred ones. Males had larger home ranges (mean 121.6 ha) than females (mean 23.0 ha). Mean daily movement was 430 m for males and 180 m for females; the maximum movement was 2800 m for males and 680 m for females. Most of the preferred habitat occurred in fragments larger than the area requirement of an individual squirrel, and even the most isolated fragments were within a trivial range for squirrels. Therefore, we predict that the random sample hypothesis will give a good prediction of the effects of forest fragmentation on the red squirrel in this landscape. However, if the proportion of avoided habitats increases, isolation and fragment size might affect the population density of red squirrels and the population size would be smaller than predicted from the random sample hypothesis.
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Survival was positively correlated with body weight in the 2nd winter of life, independent of body length. Females weighing <300 g did not come into oestrus. Female body weight and dominance were the best predictors of fertility. In coniferous habitat, body weight when lactating and the difference in weight over the lactation period predicted success in raising offspring. In deciduous habitat body weight was the best predictor, while the probability of having young was negatively influenced by body length and age. In coniferous woodland, both body weight and longevity were significantly correlated with lifetime reproductive success of females. In deciduous woodland, only body weight had a significant effect due to early breeding in some females with poor survival. Body length was weakly correlated with habitat quality, but there was a strong effect of habitat quality on body weight. Large squirrels settled in areas with the best seed-crop, and gained more weight than those that settled in areas with a poorer seed-crop. -from Authors
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A study on the behaviour of a population of squirrels, the "serelepe" (Sciurus ingrami), was conducted in a secondary araucaria forest in southern Brazil. Forty-three squirrels were marked and observed between 05:00 and 18:00 daily. The largest number of males were trapped during the winter, coinciding with an increase in the number of agonistic encounters and mating chases. Two peaks in occurrence of trapped pregnant females were found, one during the winter and the other in the summer. The population density was 0.89 squirrels/ha and the mean area occupied by males was larger during the winter mating period, decreasing gradually during subsequent seasons. The diurnal activity of S. ingrami exhibited bimodal curves in all seasons, with one peak in the morning and another in the afternoon. During the winter, the morning peak was greater in amplitude than during the other seasons. In the spring and summer, a marked increase in the activity of the squirrels during the hottest hours occurred. The morning peak of activity occurred earlier in the spring and summer and later in the autumn and winter. The daily time spent inrest, displacement, feeding, and maintenance showed seasonal variation similar to that shown by other sciurids.
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In non-native conifer plantations characterized by strong spatial and temporal variations in the availability of tree seeds in Spadeadam Forest, northern England, the home range and habitat use of red squirrels Sciurus vulgaris was very flexible. Males tended to have much larger home ranges than females and core-areas of most breeding females seemed mutually exclusive. Adult female red squirrels were found to increase their home range and core-area size in forest patches where food was less abundant. Home-range size was significantly related to home-range quality and the extent of overlap by other females. In contrast with high-quality continuous conifer forests: (1) a considerable proportion of adult males and females at Spadeadam shifted home range, (2) both sexes had much larger home ranges than reported from other habitats in Britain or Belgium. Many ranges were multinuclear, particularly from January onwards, when supplies of seeds become depleted through consumption and seed shed. Squirrels tracked the availability of conifer seeds (lodgepole pine cones throughout the study, Norway spruce cones in spring 1992 and Sitka spruce cones in autumn 1993) and intensively used several non-adjacent activity centres in temporally food-rich patches. Consequently, habitat preference changed markedly with time. The squirrels seemed to maximize nitrogen intake and to avoid the smaller seeds when possible. This resulted in an overall preference for a mixed diet of lodgepole pine and spruce seeds and avoidance of Sitka spruce seeds when Norway spruce seeds were available. These results lend support to the hypothesis of Ostfeld (1985) that when food is sparse and patchily distributed, females should develop intrasexual territoriality, concentrating their activity in food-rich patches, while males should be non-territorial and adapt their space use to the distribution of females.
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1. The population ecology of grey squirrels Sciurus carolinensis living in a 9-ha oak Quercus robur wood in southern England was studied between 1976 and 1987 using live-trapping techniques. Trapping was carried out in winter, spring and summer. The availability of tree seeds during the autumn of each year, and the severity of cold weather over each winter were also measured to examine their effects on squirrel population dynamics. 2. Capture probabilities of squirrels in winter, and to a lesser extent in spring, were inversely related to food availability and data from these two seasons were not considered dependable. The analyses concentrated on the summer populations. 3. The long-term average summer density of squirrels was high at 8.8 ha(-1) (SE 3.41 ha(-1)) demonstrating that the oak wood was high quality habitat for grey squirrels. Over 10 of the 12 years, summer densities were remarkably similar, ranging between 7 ha(-1) and 10 ha(-1) (mean 8.5 ha(-1), SE 0.95 ha(-1)). However, numbers were driven upwards in 1977 to a density approaching 18 ha(-1) and downwards in 1982 to a density of about 3 ha(-1): a 6-fold difference. 4. In good seed years, breeding starts in December, in poor seed years the start of breeding is deferred until the spring. There was no or very little spring breeding in 5 years when food supplies were poor. Female reproductive success was positively associated with food availability. Partial correlation analysis showed that the level of association was not improved when the effects of winter weather were taken into account. The number of new adult females in the summer population was positively associated with food availability but there was no association between new males and food. This suggests that food availability is more important to breeding females than breeding males. 5. Persistence from summer to winter was positively associated with food availability, but persistence from summer to spring and to the following summer were not. Partial correlation analyses showed that the severity of winter weather tended to mask the effects of food availability on persistence and the partial correlation coefficients were higher when the effects of weather were held constant. Adult females had the highest persistence between summers (52%, n = 11, SE 6%), followed by juvenile females (38%, n = 7, SE 8%), adult males (36%, n = 11, SE 4%), and juvenile males (21%, n = 7, SE 7%). The persistence of adult males but not females was inversely related to the initial number of males present. 6. In males, there was no significant difference in winter body mass between years and winter body mass was not associated with food availability, although there were very few data for winters when the food supply was good. In 7 years when the food supply was poor to moderate, there was an increase in mean body mass between summer and winter in 4 years, and a decrease in 3 years. 7. The data were explored using ordination techniques; first a standardized principal component analysis and then the canonical form of principal component analysis or redundancy analysis. The analysis was carried out on years derived from MNA of males and females and various combinations of the environmental variables: food availability (FOOD) and the severity of winter weather (TEMP). The ordination biplots clearly showed the high correlation between MNA males and MNA females and that FOOD was the most important environmental variable. TEMP on its own had no effect but FOOD x TEMP was important. 8. Following on the exploratory data analysis and for predictive purposes, a general linear model between the numbers of squirrels in the summer populations and sex, FOOD and FOOD x TEMP as explanatory variables accounted for 77% the variance in squirrel numbers among years. 9. This study shows that tree seed availability is the most important factor limiting grey squirrel densities, but this factor both positively and negatively interacts with the severity of winter weather to affect grey squirrel population dynamics.