Research Article
Species Composition of Tropical Understory Birds in
Threatened East African Coastal Forests Based on Capture Data
Robert B. Modest and Shombe N. Hassan
Department of Wildlife Management, Sokoine University of Agriculture, P.O. Box 3073, Morogoro, Tanzania
Correspondence should be addressed to Robert B. Modest; robertbya@yahoo.com
Received 10 December 2015; Revised 17 February 2016; Accepted 3 March 2016
Academic Editor: Eugene S. Morton
Copyright © 2016 R. B. Modest and S. N. Hassan. his is an open access article distributed under the Creative Commons
Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is
properly cited.
he East African coastal forests are subject of haphazard modiication following anthropogenic pressures including tree cutting and
clearing for agriculture. hese activities, which are leading cause of habitat disturbance and species loss, are the major challenge
in the management of sensitive wildlife species such as forest understory birds. his study investigated species composition of
understory birds in the coastal forests of northeastern Tanzania to generate information for the management of the landscape and
biodiversity in the area. Using mist nets, birds were trapped from core and edge habitats of representative forest patches. Trapped
birds were classiied to species level and categorized into bird guilds based on their levels of forest dependence. It was found out
that species richness was inluenced by forest patch size rather than level of habitat disturbance. Edge habitat was also found to
be important in hosting higher number of forest understory birds, especially generalists—but this should be treated with caution
because following habitat destruction that is ongoing in the study area, there is a danger of generalist wiping out specialist species
due to competitive exclusion. Strict control measures to stop illegal tree cutting and agricultural activities near the forests were
recommended for sustainable conservation of the understory birds in the forests.
1. Introduction
On telling the status and complexity of forest ecosystems,
understory bird species composition is of particular consid-
eration [1–3]. he role of understory birds in shaping the
forests ranges from seed dispersal [4, 5] to pollination as well
as pest control [6], among others. However, persistence of
most species of this ecological guild within forested habitat is
determined by many factors, such as canopy cover and vege-
tation stratiication [7–9], and microclimatic conditions [10–
12]. Unfortunately, in most of tropical landscapes, these vital
factors which deine forest structures are subject of haphazard
modiication following human actions such as man-made
ires and unsustainable use of the forest resources—with
ultimate negative consequences on bird diversity [11, 13–16].
Under this scenario, the role of understory birds in particular
frugivores is indispensable mainly on dispersal of seeds to
ill gaps that are let behind ater negative anthropogenic
activities including uncontrolled harvest of forest lora—the
process which helps in ecological succession and recovery
of habitats [4, 5]. An additional, yet important role of forest
understory birds can be noted within the agriculture sector,
whereby loss or decline of understory insectivores owing to
habitat degradation, for example, has obvious implications
including crop loss as a result of increased abundance in
invertebrate pests [1, 6].
he East African coastal forests are reknown for their
high bird diversity and endemism [17, 18]. However, these
forests face uncontrolled human livelihood issues that include
tree cutting, charcoal burning, and habitat clearing for
agriculture [15, 17, 19]. hese deleterious activities lead to
habitat disturbance and fragmentation with eventual negative
consequences on bird populations [4, 18]. Previous researches
within the forests such as that of Hassan et al. [15] based
on point count and that of Korfanta et al. [2] as well as
Newmark [1] based on mist netting reported that deleterious
anthropogenic activities were the major reason for the uneven
distribution of avifauna species among the forests.
Hindawi Publishing Corporation
International Journal of Zoology
Volume 2016, Article ID 1390364, 9 pages
http://dx.doi.org/10.1155/2016/1390364