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Authors
Abstract(s)
Os Açores são um arquipélago que pertence à região biogeográfica da Macaronésia, composto
por nove ilhas oceânicas. Rica em endemismos, a ilha de São Miguel é a maior, a sua vegetação
apresenta elevado grau de invasão, sendo escassas as áreas com vegetação nativa, denominada
Laurissilva.
A comunidade de Passeriformes é composta por 13 espécies residentes, uma endémica da ilha
e cinco subespécies endémicas do arquipélago. No entanto, esta biodiversidade encontra-se ameaçada
pela reduzida área de floresta nativa que persiste. Com este trabalho pretende-se identificar os fatores
que afetam as características das comunidades de Passeriformes florestais na ilha de São Miguel, mais
precisamente: (1) Comparar a comunidade de floresta nativa e exótica; (2) Comparar a comunidade de
Inverno e Primavera; (3) Identificar outras variáveis ambientais determinantes das características da
comunidade.
Foram realizados 40 pontos de contagem no Inverno e na Primavera, em duas zonas, cada
uma com metade dos pontos em vegetação nativa e outra metade em vegetação exótica.
No total foram observadas 12 espécies de Passeriformes, 11 em ambos os tipos de vegetação.
As espécies nativas foram as mais abundantes, estando as endémicas mais associadas à vegetação nativa
e as introduzidas à vegetação exótica. A riqueza e a abundância foi idêntica em ambas as estações do
ano. A riqueza nos pontos foi maior na Primavera, em vegetação nativa e a altitudes intermédias. A
abundância nos pontos foi maior no Inverno, em vegetação nativa, a altitudes intermédias e em pontos
ao longo da estrada florestal.
Apesar dos Passeriformes florestais nativos poderem ocorrer tanto na vegetação nativa como
na exótica, estão mais associadas à primeira e também parecem preferir áreas de altitude intermédia.
Como tal, recomenda-se a conservação e restauro prioritário destas áreas para assegurar a sobrevivência
desta comunidade única de Passeriformes.
The Azores are an archipelago that belongs to the biogeographic region of Macaronesia, composed by nine oceanic islands. Rich in endemism, the island of São Miguel, is the largest, the vegetation presents a high degree of invasion, with few forest areas with native vegetation, called Laurissilva. The passerine community is composed of 13 resident species, one endemic of the island, and five subspecies endemics from the archipelago. Nevertheless, this biodiversity is threatened by the small area of native forest that persists. The main objective of this work was to identify the factors that affect the characteristics of the forest passerine communities on the island of São Miguel, more precisely: (1) Comparing the community of native and exotic forest; (2) Comparing the community of winter and spring; (3) Identifying other environmental variables that determine the characteristics of the community. Fourty sampling points were carried out in winter and in spring, in two different zones, each with half of the points in native vegetation and in exotic vegetation. In total, 12 species of passerine birds were observed, 11 in both types of vegetation. Native species were the most abundant, with endemic species more associated with native vegetation and introduced species with exotic vegetation. Species richness and abundance were identic in both seasons. Speciesrichness at the sampling points was higher in the spring, in native vegetation and at mid-altitude. The abundance at the sampling points was higher in winter, in native vegetation, as well as in midaltitude at points along the forest road. Although the forest passerines may occur in both native and exotic vegetation, they are more associated with native vegetation and seem to prefer mid-altitude areas. As such, priority conservation and restoration of these areas is recommended to ensure the survival of this unique community.
The Azores are an archipelago that belongs to the biogeographic region of Macaronesia, composed by nine oceanic islands. Rich in endemism, the island of São Miguel, is the largest, the vegetation presents a high degree of invasion, with few forest areas with native vegetation, called Laurissilva. The passerine community is composed of 13 resident species, one endemic of the island, and five subspecies endemics from the archipelago. Nevertheless, this biodiversity is threatened by the small area of native forest that persists. The main objective of this work was to identify the factors that affect the characteristics of the forest passerine communities on the island of São Miguel, more precisely: (1) Comparing the community of native and exotic forest; (2) Comparing the community of winter and spring; (3) Identifying other environmental variables that determine the characteristics of the community. Fourty sampling points were carried out in winter and in spring, in two different zones, each with half of the points in native vegetation and in exotic vegetation. In total, 12 species of passerine birds were observed, 11 in both types of vegetation. Native species were the most abundant, with endemic species more associated with native vegetation and introduced species with exotic vegetation. Species richness and abundance were identic in both seasons. Speciesrichness at the sampling points was higher in the spring, in native vegetation and at mid-altitude. The abundance at the sampling points was higher in winter, in native vegetation, as well as in midaltitude at points along the forest road. Although the forest passerines may occur in both native and exotic vegetation, they are more associated with native vegetation and seem to prefer mid-altitude areas. As such, priority conservation and restoration of these areas is recommended to ensure the survival of this unique community.
Description
Tese de Mestrado, Biologia da Conservação, 2022, Universidade de Lisboa, Faculdade de Ciências
Keywords
Abundância Ecologia de comunidades Riqueza de espécies Vegetação exótica Vegetação nativa Teses de mestrado - 2023