scholarly journals Mitochondrial DNA diversity and population structure of a forest-dependent rodent, Praomys taitae (Rodentia: Muridae) Heller 1911, in the fragmented forest patches of Taita Hills, Kenya

2008 ◽  
Vol 104 (11/12) ◽  
Author(s):  
Silvester Nyakaana ◽  
Christopher Tumusiime ◽  
Nicholas Oguge ◽  
Hans R. Siegismund ◽  
Peter Arctander ◽  
...  
Keyword(s):  
Mitochondrial Dna ◽  
Demographic History ◽  
Total Sample ◽  
Forest Fragments ◽  
Forest Patches ◽  
Fragmented Forest ◽  
Taita Hills ◽  
Hierarchical Amova ◽  
Indigenous Forest ◽  
The Hill

The population genetic structure of the forest-dependent rodent, Praomys taitae, sampled from nine indigenous forest fragments distributed over three ranges of the Taita Hills in Kenya, was determined using mitochondrial DNA (mtDNA) control region sequence variation. Thirty-three unique haplotypes were observed in a total sample of 132 individuals, whereas the number of different haplotypes per population ranged from two to 10. An overall low nucleotide diversity of 0.9% was observed in the total sample but varied widely between populations (0.2–1.3%). Significant genetic differentiation was observed in 30 of the 36 possible pair-wise comparisons between populations, while a hierarchical AMOVA revealed significant genetic subdivision between groups of populations on the three hill ranges of Dabida, Mbololo and Kyulu (FCT = 0.404, P less than 0.01), among populations on each of the hill ranges (FSC = 0.112, P less than 0.01) and among populations in the total sample (FST = 0.471, P less than 0.001). Demographic history analyses based on pair-wise nucleotide sequence mismatch distributions revealed that all the populations were in mutation-drift disequilibrium except the populations of the Kyulu and Ronge forest fragments.

scholarly journals Natural History Observations on a Warty Frog: Callulina dawida (Amphibia: Brevicipitidae) in the Taita Hills, Kenya

ISRN Zoology ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-9
Author(s):  
Patrick K. Malonza
Keyword(s):  
Natural History ◽  
Cold Season ◽  
Tree Plantations ◽  
Forest Fragments ◽  
Pitfall Trapping ◽  
Taita Hills ◽  
Exotic Tree ◽  
Indigenous Trees ◽  
Indigenous Forest ◽  
Privately Owned

Amphibian populations are declining throughout the world, but most of the susceptible species possess particular biological attributes. Understanding these traits plus the environmental factors responsible for declines greatly aids conservation prioritization and planning. This paper examines the natural history observations and ecological characteristics of Callulina dawida, a frog endemic to the montane forests of the Taita Hills, Kenya. Sampling was accomplished by use of standardized pitfall trapping, transects, and time-limited searches. Mean monthly temperature and elevation significantly influenced the species distribution and abundance but mean monthly rainfall did not. The species was rare or absent during the cold season and its abundance increased with elevation. Breeding occurred during the long dry season (June to October) with juveniles being abundant between January and March. Available evidence shows that this species deposits a cluster of large yolk-rich eggs on the forest floor with maternal care and direct development. Its occurrence only within highly fragmented indigenous forests makes the species worth listing as critically endangered. To conserve this species, all remaining indigenous forest fragments including those communally or privately owned should be preserved and connected through planting of indigenous trees along stream valleys. In addition, the exotic tree plantations should be replaced with indigenous trees to restore the species habitat.

scholarly journals The importance of orangutans in small fragments for maintaining metapopulation dynamics

2020 ◽  
Author(s):  
Marc Ancrenaz ◽  
Felicity Oram ◽  
Nardiyono Nardiyono ◽  
Muhammad Silmi ◽  
Marcie Elene Marcus Jopony ◽  
...  
Keyword(s):  
Oil Palm ◽  
Agricultural Landscapes ◽  
Genetic Connectivity ◽  
Forest Fragments ◽  
Multiple Use ◽  
Conservation Areas ◽  
Forest Patches ◽  
Fragmented Forest ◽  
Ground Survey

Orangutans (Pongo spp.) occur at low densities and therefore large areas are necessary to sustain viable metapopulations, defined here as sets of conspecific units of individuals linked by dispersal. Historically, orangutans lived in large contiguous areas of intact rainforest, but are now increasingly found in agricultural and other landscapes modified by people. Here we collate evidence of orangutans utilizing isolated forest fragments (< 500 ha) within multiple-use landscapes dominated by oil palm monoculture across Borneo. Orangutan signs (i.e. nests) were evident in 76 fragments surveyed by helicopter, and in 50 of 70 additional fragments surveyed on the ground; on average 63 ha in size. This includes presence of adult resident females with dependent young confirmed in 40% of the fragments assessed by ground survey. Our study revealed some resident females are raising offspring in isolated forest patches within mature oil palm stands. This not only confirms that some forest patches can sustain orangutans, but indicates migratory males are capable of reaching these fragments scattered throughout the multiple-use landscape. Therefore, orangutans that use or live in even small isolated forest patches are an essential part of the overall metapopulation by maintaining gene flow between, and genetic connectivity within, populations distributed across larger multiple-use landscapes. Orangutan survival is commonly thought to be low in small, isolated forest patches, and the customary management strategy is to remove (translocate) these individuals and release them in larger forests. In some cases, translocations may be necessary, i.e. in case of fire or when the animals are in eminent danger of being killed and have no other refuge. However, the small amount of data available indicates that mortality rates during and after translocations are high, while the impacts of removing animals from spatially dispersed metapopulations are unknown. Therefore, we argue the current policy of routine translocation rather than conserving the species within human-modified landscapes could inadvertently decrease critical metapopulation functionality necessary for long-term viability. It is clear that orangutans need natural forest to survive, but our findings show that fragmented agricultural landscapes can also serve as complementary conservation areas in addition to fully protected areas if they are well designed with ecological connections, and if orangutan killing can be prevented. To achieve this, we call for a paradigm shift from the traditional large single forest model to one that emphasizes metapopulation functionality in the fragmented forest - human use matrix characteristic of the Anthropocene.

scholarly journals Effects of Forest Disturbance on Vegetation Structure and Above-Ground Carbon in Three Isolated Forest Patches of Taita Hills

2016 ◽  
Vol 06 (02) ◽  
pp. 142-161 ◽  
Author(s):  
Chemuku Wekesa ◽  
Nereoh Leley ◽  
Elias Maranga ◽  
Bernard Kirui ◽  
Gabriel Muturi ◽  
...  
Keyword(s):  
Vegetation Structure ◽  
Forest Disturbance ◽  
Forest Patches ◽  
Taita Hills

scholarly journals Terrestrial mammal diversity in forests close to pineapple crops, Cutris San Carlos, Costa Rica.

2015 ◽  
Vol 7 (1) ◽  
pp. 59-65
Author(s):  
Jonathan Navarro P ◽  
Alexander Gómez L
Keyword(s):  
Conservation Status ◽  
Forest Fragments ◽  
Negative Effects ◽  
Forest Patches ◽  
Wild Mammals ◽  
Predator Prey ◽  
Terrestrial Mammal ◽  
Terrestrial Mammals ◽  
San Carlos ◽  
Mammal Diversity

Pineapple crops reduce the size of forest fragments and generate pressure on biodiversity in the remnants. To determine potential negative effects of forest fragmentation we assessed diversity and composition of terrestrial mammals in forest patches on three farms under pineapple crops. We placedSherman and Tomahawk traps, footprints traps near water bodies, and made daily tracks to obtain traces and direct observation of mammals. We identified seven species of wild mammals, mostly omnivorous and under a least concern conservation status. The effect of cover type generated by the pineapple crops is consistent with mammal composition. Pineapple crops could enhance the most common wildlife problems, such as predator-prey relationships. Therefore, pineapple plantations, by causing fragmentation and lack of connectivity among forest patches, threaten extinction of mammals in some of their original range.

Effects of forest fragmentation on neotropical fauna: current research and data availability

1995 ◽  
Vol 3 (2) ◽  
pp. 191-211 ◽  
Author(s):  
Holly L. Offerman ◽  
Virginia H. Dale ◽  
Scott M. Pearson ◽  
Robert V. O'Neill ◽  
Richard O. Bierregaard Jr.
Keyword(s):  
Forest Fragmentation ◽  
Amazon Basin ◽  
Data Availability ◽  
Forest Fragments ◽  
Forest Patches ◽  
Neotropical Fauna ◽  
Using Data ◽  
Spatially Explicit Data ◽  
Biological Dynamics

Tropical deforestation often produces landscapes characterized by isolated patches of forest habitat surrounded by pasture, agriculture, or regrowth vegetation. Both the size and the distribution of these forest patches may influence the long-term persistence of faunal species. There is, therefore, a pressing need to understand faunal responses to patterns of forest fragmentation in tropical systems. The Biological Dynamics of Forest Fragments Project (BDFFP) provides a wealth of autecological information and spatially explicit data describing habitat use and movement of fauna between Amazonian forest fragments. Using data from the BDFFP and other studies in the Amazon Basin, this paper reviews the information available on tropical insects, frogs, birds, primates, and other mammals that can be used to identify and classify species most at risk for extirpation in fragmented forests.Key words: Amazonia, habitat fragmentation, rainforest, fauna, Biological Dynamics of Forest Fragmentation Project.

Sign in / Sign up

Export Citation Format

Share Document