Forest Fragment In Southeastern Brazil Research Articles

VARIATION IN THE DIET OF THE BROWN-NOSED COATI (NASUA NASUA) IN SOUTHEASTERN BRAZIL

We determined the diet of the brown-nosed coati (Nasua nasua) in an urban semideciduous forest fragment in southeastern Brazil. Coati feces were collected weekly for 3 years. The 226 fecal samples included plant parts (85.4%), insects (75.7%), millipedes (53.9%), fruits (48.7%), spiders (33.6%), organic waste (9.7%), vertebrates (9.3%), and gastropods (2.6%). More spiders and millipedes were consumed during the wet season, and more fruits were consumed in the dry season. The consumption of vertebrates, fruits, and millipedes differed among different years. The monthly consumption of spiders and millipedes was positively correlated with rainfall. The consumption of fruits was negatively correlated with the consumption of millipedes and insects. Fruits were an important resource during periods of arthropod scarcity. Coatis ingested and defecated intact seeds of 49 plant species, indicating that they can be important seed dispersers. The consumption of vertebrates was occasional and varied.

Florística e estrutura do componente arbustivo-arbóreo de uma floresta higrófila da bacia do rio Jacaré-Pepira, SP, Brasil

As florestas higrófilas são formações ribeirinhas caracterizadas por ocorrerem em solo permanentemente encharcado e restritas a pequenos fragmentos junto a outros tipos vegetacionais. Neste trabalho caracterizaram-se a florística e a estrutura do componente arbustivo-arbóreo (plantas com DAP>5cm) de uma área de 0,36ha de floresta higrófila localizada em Brotas (48º06'W 22º16'S, 470m.s.m.), Estado de São Paulo, usando-se método de parcelas (total de 24 parcelas). No total foram amostrados 735 indivíduos, distribuídos em 32 famílias e 51 espécies. As espécies que se destacaram na comunidade devido aos elevados valores de importância foram Calophyllum brasiliense Camb., Protium almecega L. Marchand, Podocarpus sellowii Klotzch., Tapirira guianensis Aubl. e Dendropanax cuneatum DC. Decne. & Planch. O índice de diversidade de Shannon foi igual a 2,81, valor pouco superior aos descritos para florestas semelhantes. Na comunidade, as espécies generalistas com relação ao encharcamento do solo e as de solo drenado contribuíram na riqueza total (juntas 62% do total de espécies amostradas), enquanto as espécies de solo encharcado tiveram maior contribuição na composição da dominância (66% da dominância total) e densidade (67% da densidade total) relativas. A diversidade de situações topográficas e a entrada de espécies da vegetação do cerrado adjacente permitiram que espécies com diferentes exigências hídricas se estabelecessem na área relativamente pequena da floresta e influenciaram fortemente a florística e estrutura da comunidade.

Notes on the occurrence of an aberrant coloration in Eulaema nigrita (Hymenoptera: Apidae: Euglossina) in forest fragments in Southeastern Brazil

[No abstract]

Metapopulation viability of the marsupial Micoureus demerarae in small Atlantic forest fragments in south‐eastern Brazil

AbstractA population viability analysis (PVA) was carried out for populations of the arboreal didelphid Micoureus demerarae in eight small (1.5–15.0 ha) forest fragments in south‐eastern Brazil. Analysis was based on field data obtained through demographic studies carried out since 1995. Populations are small, but connected by dispersing individuals, thus forming a metapopulation. Frequency of catastrophic fires was estimated from the Reserve's historical records. We used the computer package VORTEX for all analyses. All populations and the metapopulation were found to be endangered within 100 years (extinction probability > 0.98). A sensitivity analysis was run varying six parameters: three demographic (sex ratio, migration and mortality rates), two environmental (K, fire frequency) and one genetic (level of inbreeding depression). Genetics, K, mortality rates and sex ratio seemed to play major roles to population persistence, whereas catastrophes and migration rates had a secondary role. Among demographic factors, extinction rate was least sensitive to migration rate. Micoureus demerarae can be used as a model species, thus improving our knowledge of how extinction‐prone populations of neotropical arboreal marsupials in forest fragments might be, and which management actions could decrease such risks.

Metapopulation viability of the marsupial Micoureus demerarae in small Atlantic forest fragments in south-eastern Brazil

Metapopulation viability of the marsupial Micoureus demerarae in small Atlantic forest fragments in south-eastern Brazil

Feeding behavior of Geoffroy's marmoset (Callithrix geoffroyi) in an Atlantic forest fragment of South-eastern Brazil.

We report on the diet and feeding behaviour of a group of Geoffroy's marmosets (Callithrix geoffroyi) in an Atlantic forest fragment in south-eastern Brazil, studied during the period February 1993 to Januaray 1994. Major food categories were gums (68.6%) fruits (15%), and small animal prey (invertebrates 14.6% and vertebrates 0.8%). Dietary changes were observed between the wet and dry seasons, although they were not statistically significant. Insects and gums were consumed throughout the year but fruits were more prevalent in the diet in the wet season. Plant species exploited for their gums includedInga stipularis, followed byAcacia paniculata, Paulinia carpopodia, andBauhinia angulosa. Chemical analysis of the gum of the four species most used all presented high values for carbohydrates and crude proteins. Fruits of an unidentified species of Myrtaceae (sp. 2) were consumed the most. Animal prey consisted mainly of insects, arachnids, snails, and in three cases, lizards and frogs, with orthopterans being the most prevalent insect prey. This study demonstrates thatC. geoffroyi efficiently exploits resources typically available in secondary and disturbed forest habitat. The main threat to the species is forest destruction, degradation, and fragmentation, but the management of small forest fragments may be an effective corservation strategy.

Diet of buffy tufted-eared marmosets (Callithrix aurita) in a forest fragment in Southeastern Brazil.

The feeding ecology of the Atlantic forest marmosets (Callithrix spp.) in southeastern Brazil is poorly known, and few studies have focused on buffy tufted-eared marmosets, Callithrix aurita. We determined the food items and investigated the seasonal variation in the diet of a group of four Callithrix aurita in a 17-ha semideciduous forest fragment in southern Minas Gerais State, Brazil. We recorded daily feeding activities between October 1994 and September 1995 using scan sampling at 5-min intervals. The marmosets devoted feeding time to gums (50.5%), fruits (11%), and animal prey (38.5%) in a total of 499 records. Plant resources comprised 27 species from 16 families. They used Acacia paniculata (Mimosoideae, Leguminosae), the main gum source (82%), year-round. Maclura tinctoria (Moraceae) was the fruit species that they consumed most (22%). The marmosets preyed on caterpillars (33%), katydids (5%), and homopterans (4%). Feeding on fruits varied seasonally and was inversely related to gum feeding. Consumption of animal prey remained constant over the year. The wide and year-round dependence on gum suggests that Acacia may play a critical role in marmoset persistence in forest fragments.

Use of space by the marsupial Micoureus demerarae in small Atlantic Forest fragments in south-eastern Brazil

The spatial patterns presented by the marsupial Micoureus demerarae were studied through capture–mark–recapture in two small Atlantic Forest fragments (areas 7.1 and 8.8 ha). The study took place from March 1995 to August 1997. Considering all captures of each individual, males did not have larger home ranges within the fragments than did females. A negative correlation was found between home range sizes and population densities. For males, home ranges overlapped often, and were larger during the breeding season. For females, home ranges did not overlap except for a short period when there were many individuals present, and home range sizes were not significantly larger in the breeding season. Five movements between the two forest fragments were detected, across 300 m of open vegetation. All the movements were performed by males during the reproductive season. M. demerarae in the small fragments therefore displays a metapopulation structure, although possibly an atypical one where only males disperse.

Diet of the brown howler monkey Alouatta fusca in a forest fragment in southeastern Brazil

Le regime alimentaire du hurleur brun Alouatta fusca a ete etudie dans un fragment de foret du sud-est du Bresil pendant 42 mois consecutifs. Les hurleurs ont ete observes au cours de 366 prises de nourriture (un groupe ou un singe mangeant une seule plante) de 52 especes de plantes. 23 % des feuilles et 52 % des fleurs provenaient de lianes. 18 especes sont dispersees par les hurleurs sous forme de fruits et les graines de deux lianes sont mangees. Dans les petits fragments de foret d'ou la plupart des grands frugivores specialises sont absents, les hurleurs peuvent etre les principaux responsables de la dispersion des graines des grands fruits