Top PDF Limited carbon and biodiversity co-benefits for tropical forest mammals and birds

Limited carbon and biodiversity co-benefits for tropical forest mammals and birds

Limited carbon and biodiversity co-benefits for tropical forest mammals and birds

5003, 1432 Ås Norway 17 Pontifical Catholic University of Ecuador, Avenue 12 de Octubre and Vicente Ramon Roca, Quito, Ecuador Abstract. The conservation of tropical forest carbon stocks offers the opportunity to curb climate change by reducing greenhouse gas emissions from deforestation and simul- taneously conserve biodiversity. However, there has been considerable debate about the extent to which carbon stock conservation will provide benefits to biodiversity in part because whether forests that contain high carbon density in their aboveground biomass also contain high animal diversity is unknown. Here, we empirically examined medium to large bodied ground- dwelling mammal and bird (hereafter “wildlife”) diversity and carbon stock levels within the tropics using camera trap and vegetation data from a pantropical network of sites. Specifically, we tested whether tropical forests that stored more carbon contained higher wildlife species richness, taxonomic diversity, and trait diversity. We found that carbon stocks were not a significant predictor for any of these three measures of diversity, which suggests that benefits for wildlife diversity will not be maximized unless wildlife diversity is explicitly taken into account; prioritizing carbon stocks alone will not necessarily meet biodiversity conservation goals. We recommend conservation planning that considers both objectives because there is the potential for more wildlife diversity and carbon stock conservation to be achieved for the same total budget if both objectives are pursued in tandem rather than independently. Tropical forests with low elevation variability and low tree density supported significantly higher wildlife diversity. These tropical forest characteristics may provide more affordable proxies of wildlife diversity for future multi- objective conservation planning when fine scale data on wildlife are lacking.
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Limited carbon and biodiversity co-benefits for tropical forest mammals and birds

Limited carbon and biodiversity co-benefits for tropical forest mammals and birds

Abstract. The conservation of tropical forest carbon stocks offers the opportunity to curb climate change by reducing greenhouse gas emissions from deforestation and simul- taneously conserve biodiversity. However, there has been considerable debate about the extent to which carbon stock conservation will provide benefits to biodiversity in part because whether forests that contain high carbon density in their aboveground biomass also contain high animal diversity is unknown. Here, we empirically examined medium to large bodied ground- dwelling mammal and bird (hereafter “wildlife”) diversity and carbon stock levels within the tropics using camera trap and vegetation data from a pantropical network of sites. Specifically, we tested whether tropical forests that stored more carbon contained higher wildlife species richness, taxonomic diversity, and trait diversity. We found that carbon stocks were not a significant predictor for any of these three measures of diversity, which suggests that benefits for wildlife diversity will not be maximized unless wildlife diversity is explicitly taken into account; prioritizing carbon stocks alone will not necessarily meet biodiversity conservation goals. We recommend conservation planning that considers both objectives because there is the potential for more wildlife diversity and carbon stock conservation to be achieved for the same total budget if both objectives are pursued in tandem rather than independently. Tropical forests with low elevation variability and low tree density supported significantly higher wildlife diversity. These tropical forest characteristics may provide more affordable proxies of wildlife diversity for future multi- objective conservation planning when fine scale data on wildlife are lacking.
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Legacies of tropical forest fragmentation and regeneration for biodiversity and carbon storage

Legacies of tropical forest fragmentation and regeneration for biodiversity and carbon storage

Fragmentation of habitat causes a number of impacts to species, such as population reductions and local extinctions; the strength of fragmentation impacts differ depending on the taxonomic group and life-history traits of species (Turner 1996; Bender, Contreras & Fahrig 1998; Forman & Alexander 1998; Fahrig 2003). Previous studies of reservoir island archipelagos have shown that island taxa typically experience a novel hyper-disturbance regime, resulting in drastic shifts in species diversity and community composition through species turnover, and altered carrying capacity of the remaining habitat (Cosson et al. 1999b; Hanski & Ovaskainen 2000; Terborgh et al. 2001; Ferreira et al. 2012; Benchimol & Peres 2015a). Local species extinctions on reservoir islands have been observed for plants (Yu et al. 2012; Benchimol & Peres 2015a), invertebrates (Feer & Hingrat 2005; Emer, Venticinque & Fonseca 2013), birds (Yu et al. 2012), bats (Cosson, Pons & Masson 1999a), small-mammals (Lambert et al. 2003; Gibson et al. 2013), and midsized to large-bodied vertebrates (Benchimol & Peres 2015b; c). Populations of some species can become hyper-abundant on islands, and invasive species can establish, further impacting other taxa (Chauvet & Forget 2005; Feeley & Terborgh 2006; Lopez & Terborgh 2007; Gibson et al. 2013).
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Plant functional types and traits as biodiversity indicators for tropical forests: two biogeographically separated case studies including birds, mammals and termites

Plant functional types and traits as biodiversity indicators for tropical forests: two biogeographically separated case studies including birds, mammals and termites

A linkage between aboveground carbon, total organic carbon (standing vegetation, dead wood, litter and soil combined) and diversity in tree plant and termite species in Sumatra (Table S19, Online resources) suggests these variables should be examined further as candidate generic indicators. In both regions variations in soil texture and soil physical features such as bulk density exert important indirect effects on faunal diversity through their influence on plant growth and therefore on faunal habitats for which plants are the keystone providers. The same plant-based indicators can be used in other lowland forest types (Fig. S2, Appendix S2, Online Resources) although faunal baseline data are needed for proper evaluation. The lack of evidence for species-based indicators of other species reported here is consistent with findings in African tropical forests (Lawton et al. 1998 ). Where plant species identification is problematic, plant functional traits can be used as independent biodiversity surrogates. However, surrogacy is improved when functional trait and species data are combined. For this reason we suggest that the inclusion of adaptive PFTs and their component PFEs should be used to complement rather than replace species- based biodiversity assessment. The characterization of photosynthetic tissue, organs and life form in the PFEs together with vegetation structure (mean canopy height, percent canopy cover, basal area) contrasts with the more traditional and functionally restrictive (Raunkiaerean) plant life-forms and indicates greater potential for remote-sensing appli- cations and monitoring forest condition at varying scales of spatial resolution (Asner et al.
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Conservation value, biodiversity value and methods of assessment in regenerating and human disturbed tropical forest

Conservation value, biodiversity value and methods of assessment in regenerating and human disturbed tropical forest

throughout Amazonia, detailed information about the ecology and distribution of both species is currently limited. Biologists have been carrying out biodiversity surveys at the MLC since 2004, through biodiversity surveys by expedition groups and more consistently since 2010 with an all-year round field team dedicated to surveying the biodiversity of the reserve both day and night. Despite ten years of on-going research and assessment, the nocturnal and inconspicuous, silky pygmy anteater (Munari et al. 2011; Superina et al. 2010) had evaded detection (see Chapter 1 of this thesis). However, in just three months, cameras at the MLC captured two separate records of this elusive species from two trees (>400m apart; Figure 3). This provided a clear demonstration of the ability of arboreal cameras to collect novel distribution and ecological data, especially for species where this has proven difficult or impossible using traditional survey techniques. A further effective use of arboreal camera traps identified within this study is the ability of cameras to detect species in hunted areas. Mammals are often difficult to detect in hunted areas using traditional methodologies, due to human avoidance behaviours as a result of hunting pressure (Bshary 2001; Croes et al. 2007). For example, at Shipetiari where hunting for subsistence is
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Burning biodiversity: Fuelwood harvesting causes forest degradation in human-dominated tropical landscapes

Burning biodiversity: Fuelwood harvesting causes forest degradation in human-dominated tropical landscapes

5. Conclusions Unlike major sources of habitat loss and degradation, such as land-use shifts, that can be confidently measured by governments and conservationists, the cryptic sources of disturbances that usually follow habitat loss are driven by more complex socioeconomic factors ( Angelsen and Kaimowitz, 1999 ; Brashares et al. , 2011 ; Mahiri and Howorth, 2001 ). Therefore, it is time to seriously consider that, in an overpopulated world, every use of natural resources may have consequences for the long-term persistence of biodiversity in human-modified landscapes ( Melo et al., 2013 ). Yet, most of these cryptic disturbances are related to poverty traps that push human populations into poverty and make them more dependent on natural resources while natural capital is depleted ( Barrett et al. , 2011 ; Coomes et al. , 2011 ). Such chronic disturbances surely add more complexity to the response of biodiversity in face of ecosystem alterations, therefore, including the ‘‘human matrix’’ in the framework will clearly help to move conservation approaches towards a broader solution to conservation problems linked to people’s socioeconomic vulnerability ( Ellis, 2013 ). Therefore, conciliating biodiversity conservation in biologically diverse tropical forests with the poverty amelioration of a huge contingent of the human population that still depends directly on forest goods is a hard but crucial task ( Kareiva et al., 2011 ).
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Tropical tree and palmallometry and implications for forest carbon dynamics in southwestern Amazonia.

Tropical tree and palmallometry and implications for forest carbon dynamics in southwestern Amazonia.

Tropical forests play a vital role in the global carbon cycle and international policy, such as the United Nations Collaborative Programme on Reducing Emissions from Deforestation or Degradation (REDD+), but the amount of carbon they contain and its spatial distribution remain uncertain. Allometric equations used to estimate tree mass are a key source of this uncertainty, because large-scale variation in tree allometry and fundamental differences between functional groups are not accurately represented in pantropical biomass equations. This research tests the effects of accounting for sources of variation not currently explained in tree models (i.e., crown size and structure) and recognising important distinctions between functional groups (monocots vs. dicots) at both the level of individuals and across the landscape. Southwestern Amazonian forests are politically and ecologically important, but biomass estimates may be particularly uncertain in this region. Specifically, tree biomass estimates vary greatly among published models, but these models do not account for crown structure nor have their predictions been tested against directly- measured data in the southwestern Amazon. Palms are also abundant in western Amazonia but their mass has been widely misrepresented: using models developed for dicotyledonous trees is likely inaccurate because these two groups have very different structures.
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Geovisualization of forest simulation modelling results: A case study of carbon sequestration and biodiversity

Geovisualization of forest simulation modelling results: A case study of carbon sequestration and biodiversity

Sustainable forest management requires new tools to analyze spatial and temporal forest dynamics and to examine those forest parameters that are related to sustainability. We built a prototype system for data analysis and decision-making at forest enterprise level by integrating a forest ecosystem model EFIMOD-PRO (long-term prediction of forest growth and soil development) with an interactive visualization system CommonGIS for analysis of spatially and temporally related data. Using the prototype, a case study in Central European Russia simulated four silvicultural regimes over 200 years: natural development, selective forestry, legal forestry according to the Russian forestry legislation, and illegal forest practice. Exploratory analysis of the simulation results demonstrated that (1) natural stand development is the best alternative for carbon sequestration; (2) legal forest management is the best regime for timber production; (3) selective forestry combines the advantages of two previous strategies, and can be the best strategy for implementing sustainable forest management; and (4) illegal forest practices lead to a fast decrease in forest productivity and decreasing biodiversity. Interactive and dynamic visualizations with maps and statistical graphics played a crucial role in data cleaning, model validation, and analysis of simulation results. The case study demonstrated the potential of integrating
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Carbon concentration declines with decay class in tropical forest woody debris

Carbon concentration declines with decay class in tropical forest woody debris

1a, whereas 355 356 3.2 Wood properties among decay classes 357 Wood density and carbon concentration of living trees and woody debris decreased with 358 decay class in the study plots T[r]

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Assessing regional scale variability in deforestation and forest degradation rates in a tropical biodiversity hotspot

Assessing regional scale variability in deforestation and forest degradation rates in a tropical biodiversity hotspot

The results of differences in regional deforestation and forest degradation rate highlight the complexity of change processes in Madagascan habitats. For example, shifting cultivation, selective logging and cyclones are major agents of forest cover change along the eastern escarpment, which comprises the lowland evergreen and medium altitude moist evergreen forests (Brown and Gurevitch 2004; Burivalova et al. 2015); while deforesta- tion and degradation in dry forest are more likely modu- lated by shifting cultivation, livestock grazing, charcoal production and wildfires, and to a lesser degree, selective logging (Waeber et al. 2015; Feldt and Schlecht 2016). Consequently, although selective logging is often the most common cause of degradation in tropical forests (Asner et al. 2005), the influence of local drivers at the regional scales may differ or get displaced through leak- ages (i.e. spatial displacement in forest loss) (Gasparri et al. 2016). There are several explanations for these regional differences: one could be the consequence of pressures caused by in-migration of re-settlers to high elevation habitats (Devries et al. 2015). Alternatively, leakage may be driven by shifts in dryland cropping on slopes (Tanety) upland towards montane forests (V agen 2006), seasonal burning (Kull 2002b) or slow reforesta- tion of dry forests once exposed to disturbances (Zinner et al. 2014). Arguably, the dominant drivers of deforesta- tion and forest degradation have shifted to other regions or are beginning to shift in an upslope direction. This may have led to increasing trends in deforestation and forest degradation in parts of Madagascar and decreasing
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Assessment of Carbon Stocks and Biodiversity in Karore Forest, Rawalpindi-North, Pakistan

Assessment of Carbon Stocks and Biodiversity in Karore Forest, Rawalpindi-North, Pakistan

inaccessible portions of forest i.e. steeps, gullies etc. Performed forest inventory was used to draw the volume tables of the forest. The biomass of the sampled trees was estimated using the tree volume and specific gravity of the wood. Biomass estimation was performed and carbon index was calculated. Study also comprised the biodiversity survey of the region. Identification of under storey vegetation, herbarium sheets, biomass calculation and palatability of the species were observed. Carissa spinarum was evaluated in the palatable vegetation of the area. Moreover, study area depicted the on-timber forest product (NTFP) values with the wild presence of fruit trees in the locality. The output of the study showed that with the passage of time the carbon sink has now been shifting towards the carbon source and it is a dilemma for the coming decade.
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Removal of blood from laboratory mammals and birds

Removal of blood from laboratory mammals and birds

to position and fix the cannula (see Gellai & Valtin, 1979; Desjardins, 1986; Dennis et al., 1986; Van Dongen et al., 1990). In both short- and long-term cannulation it may be necessary to restrain the animal in some way to stop it removing the cannula, but this depends very much on the species. It is not always possible to leave animals with complete freedom as they may bite at the cannula. Many of the larger species seem to adapt well to long- and short-term cannulation, particularly after a period of training (acclimatization) to the restraint and some can be housed in groups with appropriate bandaging and protection for the cannula. Smaller mammals, such as rats, on the other hand are often restrained by some form of harness, swivel and tether along which the cannula runs. (This arrangement is some- times referred to as an umbilicus - see Section 4.9.) But even small mammals should be conditioned (acclimatized) to the harness before cannulation, and even then stress may still occur. Cannulae can be maintained in
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Assessing the Floristic Biodiversity and Carbon Stock in a Republic of Congo’s Forest Ecosystem

Assessing the Floristic Biodiversity and Carbon Stock in a Republic of Congo’s Forest Ecosystem

Concerning woody trees, the circumference was first measured using a tape measure at 1.3 m from the ground and the diameter calculated on site. The di- ameter of the trees was measured above the buttresses or stilt roots. The height was then measured using the vertex and the species was identified. The height of considered tree was which of the highest branch. To finalized, a number was as- signed in ascending order and marked with red paint to each tree measured and identified. Species identification was made with the naked eye using the follow- ing botanical characteristics: bark shape, latex color, leaf arrangement, crown shape, trunk base shape, and its termination. A manual has been used as a basis for the identification of species: Botanical Manual and Inventory of Biodiversity of the Association of International Tropical Timber Technicians [23]. Regarding the case of Ricinodendron heudelotii (Baill.) Pierre ex Pax which loss its leaves, the bark allowed the identification of the species. Thus, all trees with DBH ≥ 5 cm were measured, identified and counted from band 1 to band 2 and at the same time all herbaceous and lianascent species were identified. Tree species recorded in study area have been identified using earned scientific knowledge during the biosystematics courses at university. Field work experiences during the university studies period also were a help to identify flora species of study area.
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Biodiversity and Carbon Potentials of a Nigerian Forest Reserve: Insights from the Niger Basin

Biodiversity and Carbon Potentials of a Nigerian Forest Reserve: Insights from the Niger Basin

Forest reserves are expected to host a wide array of biodiversity and provide refuge for rare species that may be threatened in nearby forest landscapes. While this is the guiding protocol for most reserves across the tropics, such as Nigeria, the extent to which they host biodiversity and act as potential stores for carbon are quite uncertain. This study used a four hectare randomly se- lected forest plots to verify the biodiversity of the reserve, its stand structure and potentials for carbon storage. Species importance value was used to summarize the composition of the landscape. Both the diversity (mean diver- sity = 0.85) and species richness (eleven species) were low. Biodiversity in the area was quite poor and was mostly composed of Elaeis guineensis and Gmelina arborea , which had relative densities of 74.6% and 11.96%, respec- tively. Over exploitation and preference for fast-growing exotic species ex- plained the poor stand structure and composition of the landscape, respec- tively. Very few tree stands were found in the mature structural class, and its capacity to facilitate regeneration and resilience seemed low. Its ability to store carbon in its biomass is equally low; since the forest landscape was much de- graded. Maximizing the vast land of the reserve for targeted carbon storage (through mass tree planting) is a potential step that could forestall carbon se- questration across the region, especially because, such vast and available (for- est) land cannot be guaranteed in most other forest landscapes.
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Spatial congruence between carbon and biodiversity across forest landscapes of northern Borneo

Spatial congruence between carbon and biodiversity across forest landscapes of northern Borneo

Slik, J.W.F., Aiba, S.I., Brearley, F.Q., Cannon, C.H., Forshed, O., Kitayama, K., Nagamasu, H., Nilus, R., Payne, J., Paoli, G., Poulsen, A.D., Raes, N., Sheil, D., Sidiyasa, K., Suzuki, E., van Valkenburg, J.L.C.H., 2010. Environmental correlates of tree biomass, basal area, wood specific gravity and stem density gradients in Borneo’s tropical forests. Glob. Ecol. Biogeogr. 19, 50–60. http://dx.doi.org/10.1111/j.1466-8238.2009.00489.x. Slik, J.W.F., Arroyo-Rodríguez, V., Aiba, S.-I., Alvarez-Loayza, P., Alves, L.F., Ashton, P., Balvanera, P., Bastian, M.L., Bellingham, P.J., van den Berg, E., Bernacci, L., da Conceição Bispo, P., Blanc, L., Böhning-Gaese, K., Boeckx, P., Bongers, F., Boyle, B., Bradford, M., Brearley, F.Q., Breuer-Ndoundou Hockemba, M., Bunyavejchewin, S., Matos, Calderado Leal, Castillo-Santiago, D., Catharino, M., Chai, E.L.M., Chen, S.-L., Colwell, Y., Robin, R.K., Clark, C.L., Clark, C., Clark, D.B., Culmsee, D.A., Damas, H., Dattaraja, K., Dauby, H.S., Davidar, G., DeWalt, P., Doucet, S.J., Duque, J.-L., Durigan, A., Eichhorn, G., Eisenlohr, K.A.O., Eler, P.V., Ewango, E., Farwig, C., Feeley, N., Ferreira, K.J., Field, L., de Oliveira Filho, R., Fletcher, A.T., Forshed, C., Franco, O., Fredriksson, G., Gillespie, G., Gillet, T., Amarnath, J.-F., Griffith, G., Grogan, D.M., Gunatilleke, J., Harris, N., Harrison, D., Hector, R., Homeier, A., Imai, J., Itoh, N., Jansen, A., Joly, P.A., de Jong, C.A., Kartawinata, B.H.J., Kearsley, K., Kelly, E., Kenfack, D.L., Kessler, D., Kitayama, M., Kooyman, K., Larney, R., Laumonier, E., Laurance, Y., Laurance, S., Lawes, W.F., Amaral, M.J., Letcher, I.L.d., Lindsell, S.G., Lu, J., Mansor, X., Marjokorpi, A., Martin, A., Meilby, E.H., Melo, H., Metcalfe, F.P.L., Medjibe, D.J., Metzger, V.P., Millet, J.P., Mohandass, J., Montero, D., de Morisson Valeriano, J.C., Mugerwa, M., Nagamasu, B., Nilus, H., Ochoa-Gaona, R., Onrizal, S., Page, N., Parolin, P., Parren, M., Parthasarathy, N., Paudel, E., Permana
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The effects of climate change on tropical birds

The effects of climate change on tropical birds

limited knowledge of how future changes in temperature may af- fect rainfall patterns, and how further increases in already high temperatures and/or changes in rainfall regimes may affect the availability of other sources of water and food. The disappearance of water sources is likely to be devastating for these ‘‘oasis’’ com- munities, and the added stress of higher temperatures and possibly scarcer rainfall could test the tolerances of even these seemingly hardy species. Even small temperature increases can greatly increase the amount of birds’ evaporative water loss. Hotter weather due to climate change is expected to test the ability of desert birds to sustain their water balance, and climate change is expected to lead to more frequent episodes of catastrophic mortal- ity by the 2080s. Modeling suggests that small desert birds will require 150–200% more water during the hottest period of the day to survive predicted increases in maximum daily temperature ( McKechnie and Erasmus, 2006; McKechnie and Wolf, 2010 ). 2.7. Birds in human-dominated landscapes
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An allometric approach to quantify the extinction vulnerability of birds and mammals

An allometric approach to quantify the extinction vulnerability of birds and mammals

Gittleman 2002). Because we could not find allomet- ric relationships for N D for all four species groups, we used empirical data on the global current population densities of birds (618 non- carnivorous and 115 carniv- orous species; BirdLife International 2013) and mam- mals (584 non- carnivorous and 78 carnivorous species; Jones et al. 2009) to derive corresponding intercept values. Because BirdLife International (2013) reports global population sizes instead of densities, we divid- ed the population sizes by the reported geographical range sizes to arrive at population densities for birds. For each of the four species groups, we divided the ob- servations into variably spaced logarithmic mass bins including 15 data points each. Per bin, a median pop- ulation density was calculated (similar to, e.g., Savage et al. 2004b, Agosta and Bernardo 2013). The median densities were related to body size using Ordinary Least Squares (OLS) regression (see Table 1 and Appendix S1 in the Supplemental Material). To arrive at the current total number of individuals for a species (N 0 ), we mul- tiplied the current population densities (N D ) with the geographical range size (A).
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Soundscape analysis and acoustic monitoring document impacts of natural gas exploration on biodiversity in a tropical forest

Soundscape analysis and acoustic monitoring document impacts of natural gas exploration on biodiversity in a tropical forest

The increase in overall detections of nectarivores during the drilling phase may simply be due to a change in season and plant phenology; however, detections were twice as high near the plat- form than at any other distance. At the edge, as in forest gaps, greater insolation favors colonization of plants utilized by nectari- vores ( Feinsinger et al., 1988 ). For this reason, nectarivores often frequent forest edges and can become more abundant at edges or gaps relative to other parts of the forest ( Levey, 1988; Stouffer and Bierregaard, 1995 ), particularly generalist nectarivores ( Feinsinger et al., 1988 ). In fact, frugivores can be found preferentially in gaps and edges as well, as they disperse seeds produced by many gap col- onizing plants ( Levey, 1988 ). Given the timing of operations, with the opening of the platform in May 2014, it is possible that we will see a continual presence of nectarivores closer to the edge, and even a further increase in frugivore detections as edge plants establish, although the relationship between frugivores and edges or gaps is as not well defined ( Levey, 1988; Schemske and Brokaw, 1981 ). Nevertheless, it is also important to note that the detection pattern found for frugivorous and nectarivorous birds may in fact reflect patterns of landscape usage rather than residence, as these groups are more likely to track ephemeral resources across large distances and are less likely to hold stable territories than insectivorous birds ( Stutchbury and Morton, 2001 ).
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Response of tropical birds to habitat modifications in fragmented forest patches: A case from a tropical lowland rainforest in south-west Sri Lanka

Response of tropical birds to habitat modifications in fragmented forest patches: A case from a tropical lowland rainforest in south-west Sri Lanka

est specialist birds. Habitat edges or ecotones are often con- sidered landscape structures that influence bird communities, and bird communities respond differently to structurally com- plex edges (Vâlcu 2006). The forest-home-garden interface sampled in this study predominantly consisted of tea, grown under shade trees with a mixture of multi-purpose trees and fruit trees present in home gardens. Similar croplands in the interface managed under shade trees elsewhere in the tropics have reported comparable observations, with high numbers of resident and migratory bird species recorded from such edge habitats compared to the forest interior (Estrada et al. 1997, Van Bael et al. 2007). Bird diversity and composition in agricultural lands in the wet tropics are strongly influenced by the availability of diverse groups of trees and patches of sec- ondary growth (Daily et al. 2001, Hughes et al. 2002). This, along with the variety of foraging opportunities present in home gardens bordering the forest may explain the high bird diversity and richness at the forest-home-garden interface. Abandoned paddy lands, on the other hand, are dominated by grasses and structurally less diverse, and hence accounted for less bird richness. However, several endemic forest spe- cialists such as Sri Lanka Grey Hornbill, Pompadour Green Pigeon, Sri Lanka Crested Drongo, Sri Lanka Yellow-fronted Barbet, Sri Lanka Spurfowl and Sri Lanka Emerald-collared Parakeet also use edge habitats located inside or bordering the forest.
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Dosage compensation is less effective in birds than in mammals

Dosage compensation is less effective in birds than in mammals

The generally higher expression of Z genes in male versus female birds suggests that Z genes might be more likely to evolve a role in controlling sexual differentiation in birds, as compared with X genes in mammals. In order for a tissue to function differently in males and females, the expression of genes in the tissue must evolve sensitivity to one or more sex-specific factors [41]. One set of sex-specific factors is the gonadal hormones, which are widely available to tissues as signals that evolution can use to control sex differences. If diverse cells in the body of birds express many Z genes at higher levels in males than in females, then Z genes are also widely available as a set of sex-biased signals. Z genes have been proposed to regulate sexually dimorphic development of the zebra finch brain [13]. Some of the Z genes that are expressed at higher levels in zebra finch males than females, such as FST, SMARCA2, LUZP1, and CRHBP, are implicated in signal transduction or as regulators of transcription, and therefore are candidates for factors that induce sex differ- ences in tissue function.
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