Avian Community Structure as a Function of Season, Habitat ...downloads.hindawi.com/journals/ijecol/2018/2045629.pdf · Habitat Type, and Disturbance, in Mole National Park, Northern

Research ArticleAvian Community Structure as a Function of SeasonHabitat Type and Disturbance in Mole National ParkNorthern Region (Ghana)

Collins Ayine Nsor 1 Emmanuel Acquah1 Grace Mensah1

Vincent Kusi-Kyei1 and Samuel Boadi2

1Department of Ecotourism and Forest Recreation Kwame Nkrumah University of Science and Technology Kumasi Ghana2Department of Social Forestry Kwame Nkrumah University of Science and Technology Kumasi Ghana

Correspondence should be addressed to Collins Ayine Nsor ayineusyahoocom

Received 12 February 2018 Accepted 8 May 2018 Published 19 June 2018

Academic Editor Ram Chander Sihag

Copyright copy 2018 Collins Ayine Nsor et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The study assessed factors that influenced bird-habitat preference diversity and spatial distribution in Mole National Park Birdswere identified using point count sampling method while ordination techniques were performed to determine the influence ofenvironmental factors on bird-habitat preference A total of 4951 individuals belonging to 131 species were identified across thefour habitat types in the wet (n = 3033) and dry (n = 1648) seasons Despite the high abundance and richness of birds in thewoodland and shrubland habitats grassland habitat was the most diverse due to the high spatial evenness distribution of the birdsBushfire patchiness and animal trampling were the key environmental determinants in bird assemblages and habitat preferencesand accounted for 6202 and 8182 variations in the two seasons Rarer birds likeWhite-BackedVulture (NT) andWhite-HeadedVulture (CR) Bateleur Eagle (NT) and Woolly-Necked Stork (VU) with high conservation concern suggest intensification ofconservation effort while the dominance of Sahel Bush-sparrow was probably due to their broad range habitat preferences andability to adapt to environmental conditions across these habitats These species could be used as indicators of habitat quality iffuture scenarios restrict their movement or distribution in narrow range habitats

1 Introduction

The study of bird-habitat selection and use has long beenestablished as a functional field of study in bird ecology [1ndash4]Early habitat-selection theory was characterized by correla-tive models of habitat characteristics and species abundance[5 6] which subsequently evolved into models that involveddensity dependence (ie the ldquoideal-free distributionrdquo andldquoideal-despotic distributionrdquo models) [7 8] More recentlyhabitat-selection studies have shown that many factors suchas landscape structure [9ndash11] nest predation [12] com-petition [11] intraspecific attraction [13] food availabilityvariable climate diseases and human activities [14] caninfluence exactly how ldquoidealrdquo and ldquofreerdquo animals are whilemoving through a landscape and selecting habitats Habitat-selection studies have assumed a new urgency partially as a

result of the importance of incorporating both habitat anddemographic information into conservation planning [15]given recent report about global bird population decline [16]largely linked to habitat transformation [17 18] But Pulliam[19] and Caughley [15] argue that there is no guarantee thatthe presence of individuals in a given habitat is positivelyrelated to habitat quality This is so because in the absenceof behavioral or life-history information there is no way toknow if detected differences have any bearing on choices ofindividuals [12 20] Pulliam and Danielson [10] and Martin[20] therefore conclude that habitat preferences are ratherassumed to be adaptive without demonstration of increasedfitness in preferred habitats

Notwithstanding these views about bird-habitat relation-ship studies have shown particular birds to be associatedwith particular habitats [21 22] and therefore they respond

HindawiInternational Journal of EcologyVolume 2018 Article ID 2045629 14 pageshttpsdoiorg10115520182045629

2 International Journal of Ecology

quickly to changing habitats [23ndash25] Birds have been usedas surrogates for assessing the impact of habitat changes[26] and considered as good predictors of habitat qualityas they relate to changes that are associated with theirhabitats [27ndash29] Other habitat quality indicators such ashemeroby have widely been used in plant ecology to indicatethe level of disturbance of the optimal habitat for a species[30] Hemeroby is scaled on a range of ten- or five-pointscores higher scores of hemeroby meaning higher level ofdisturbance [30]

Vegetation structure (a typical floristic habitat type) isimportant in structuring avian communities [31 32] andthus their relative abundance is often associated with veg-etation community [33] Vegetative structure is frequentlyassumed to be the primary proximate factor determiningwhere and how species use resources For example SageGrouse (Centrocercus urophasianus) is strongly associatedwith sagebrush (Artemesia tridentata) Chukar (Alectorischukar) is associated with cheatgrass (Bromus tectorum) andChestnut-backed Chickadees (Parus rufescens) appears tofollow the distribution of Douglas-fir (Pseudotsugamenziesii)in California [34] In the Sudan-Guinea Savannah biomeof Ghana where continued habitat loss in protected andunprotected areas is thought to threaten bird survival [25]maintenance of vegetation structure is crucial in sustainingbird population Skowno and Bond [35] observed a stronginfluence of vegetation structure (ie mosaic of trees shrubsand open grassland in mesic African savannas) on bird-habitat use compared to floristic composition HoweverMacNally [36] suggested that floristic habitat relationships ofbirds are often influenced by the scale of observation Mac-Nally [36] concluded that it is important to consider differentobservational scales to determine the relative significance ofstructural and floristic attributes of the habitat

Although tourists have expressed satisfaction at thewildlife attraction (ie large mammals) and the environment[37] bird watching was among the least attractive possiblydue to scanty information about their preferred habitatsborne out habitat transformation Given their important rolein enhancing biodiversity and as bioindicators to ecosystemchange [16 27] birds are among wildlife attractions toMNP and other game reserves across African landscapesThus understanding bird-floristic habitat preference andthe factors that influence their spatial distribution is keyin developing right conservation measures that will sustainbird watching as part of ecotourism drive Though previousstudies have established the presence of diverse avifauna inMNP [38] and are found to be of biogeographical importancethe study did not investigate the habitat preferences and(dis)similarity of bird species assemblage in the variousfloristic habitat types and factors influencing their habitatpreference and spatial distribution The possible mechanismsunderlying the bird species distribution pattern and theuncovering of the possible mechanisms underlying thesepatterns are critical due to the intensity of land use byhumans which continues to alter the availability qualityand distribution of habitats supporting native bird species[39] This study focused on understanding bird communitystructural assemblages as a function of habitat preference and

the predictive factors that influenced their spatial distributionin the MNP in different seasons Thus we hypothesizedthat predictive factors will not alter bird (i) abundanceand richness among habitats (ii) compositional differencesamong habitats (iii) seasonality will not influence changesin abundance and richness and finally (iv) processes thatstructure assemblages in different habitats will not varyamong the habitats along seasonal transition

2 Materials and Methods

21 Study Area The Mole National Park (MNP) where thisstudy was conducted is the largest wildlife reserve in Ghanaand home to a large proportion of Sudan woodland in thenorth of Ghana It is located in the Northern Region of Ghanaand covers an area of 4577 km2 It is one of themajor tourismdestinations in the Northern Region as well as the largestprotected area in Ghana The area lies within geographiccoordinates of 9∘ 111015840 and 10∘ 101015840 N and between 1∘ 221015840 and2∘ 131015840 W and an elevation of 120 to 490 meters above sealevel (Figure 1) Average annual temperature is 28∘C whichvaries from 26∘C in December to 31∘C in March Averageannual rainfall is about 1100 mm decreasing to 1000 mm inthe north of the park [40] The dominant vegetation type inMole National Park is open savanna woodland interspersedwith grasses [41] There are at least 344 different species ofbirds inMoleNational Park and among the key protected sitesin Ghana conserving 37 endemic Sudan-Guinea Savannabiome bird species [40]

22 Sampling Procedure Asurveywas undertakenwithin thestudy area to map out designated vegetation types and thetransect points to use for bird censusWe adopted point countsampling design employed to census birds following Bibbyet al [42] Sutherland [43] and Hutto et al [44] approachin the dry (January-May 2017) and wet (June-October 2017)seasons We counted birds within a 25 m radius surroundingthe observer in four plots covering an area 60 m times 50 m(3000 m2) each in the four vegetation types (ie grasslandwoodland riparian and shrubland) These vegetation typeswere selected because they represented the general vegetationcomposition in Mole National Park The distance betweeneach plot to the other was 100 m and randomly demarcatedBirds that were detected outside the 25 m radius but stillfound within the demarcated boundaries of the plot werecounted and considered as being within the fixed-radius [4244] We chose a 25 m radius because we tended to comparebird abundances evenness distribution and richness amongthe different vegetation types Point count of birds was donetwice in the day the early hours of the morning (from0630-0930 am and in the afternoon (1530-1730 pm)when the temperature is low and most of the birds wereout feeding perching or nesting Flying over birds were notcounted because we assumed that their habitat preferencedid not strongly relate to the vegetation types found in MoleNational Park We avoided performing bird count duringwindy days since visualization of birds might be difficultBird identification was done visually using Birds of Ghanakeys developed by Borrow and Demey [45] and by their calls

International Journal of Ecology 3

Figure 1 Map of Ghana showing the study area at Mole National Park in Northern Region

using the bird sounding technique The data was collectedin eight weeks within the period of November to February2016-2017 GPS coordinates of the various sampling pointswere taken Environmental factors namely bushfire animaltrampling erosion and patchiness on each sample plot wereassessed to determine how these factors gave rise to variationsin bird abundance evenness and richness across the fourvegetation types These environmental factors were assessedon the basis of severity and scope of their threats on birdsfollowing guidelines provided by [46] A score ranging from1 to 4 (1 being lesser impact and 4 highest impact) wasused to assess scope and severity of every threat ldquoScoperdquomore precisely is referred to the percentage of the study areaaffected by a specific threat within the last 5 years (where100) corresponding to the total site area [46] whereas

severity is the intensity of a disturbance or a threat in the studyareaThe scoreswere assigned as follows 4 the threat is foundthroughout (50) the site area 3 the threat is spread in 15-50 of the study area 2 the threat is scattered (5-15) and1 the threat is much localized (lt5) Assessment of the areadisturbed was carried out within 60m by 50m in each habitattype This is because all the disturbances were observedwithin this perimeter following a preliminary survey Wefurther classified the level of disturbances following thehierarchal threat guidelines provided by Salafsky et al [47]They are as follows threats are considered comprehensivewhen they contain all possible items at least at higher levelsof the hierarchy) consistent (ensuring that entries at a givenlevel of the classification are of the same type expandable(enabling new items to be added to the classification if they


are discovered) and exclusive (allowing any given item toonly be placed in one cell within the hierarchy) [46]

3 Data Analysis

31 Species Abundance Distribution Bird abundance as ameasure of diversity was quantified using rank abundancemodel [48] In each habitat we listed the number of birdspecies say 1198781 represented by one individual and the numberof species say 119878119870 represented by 119870 individuals where 119870denotes the abundance of the most abundant species and1198781 + + 119878119870 = 119878 [49] Accordingly the sequence of relativefrequencies 119891119903=119878119903119878 (119903 = 1 K) constitutes a frequencydistribution for the number of individuals per species whichis usually referred to as the species abundance curve [49]

We then fitted the geometric model (GS) in the speciesdata (raw abundance) using the regression model approach[49] to determine how the communities are assembled ineach habitat This model approach was used in order totest against the null hypothesis (119867119900) that bird abundanceand evenness distribution did not differ in each of the fourhabitats All the species in each of the four sample plots perhabitat (four habitats) were ranked from the most to the leastabundant on the rank abundant curve [49] Each species rankis plotted on the x-axis and the abundance plotted on the y-axis

With the geometric series if a log scale is used forabundance the species exactly fall along a straight lineaccording to the model equation log119860 = 119887119900 + 1198871119877 whereA is the species abundance R is the respective rank and1198870 and 1198871 are optimized fitting parameters [50] Analysis ofcovariance (ANCOVA) was applied to test for the significantdifference of the slope of the SADs for the four habitatswhile Pearsonrsquos Chi-square test (1205942) was applied to determinewhether an observed distribution along the goodness offit statistically differed in the GS model The SAD modelis mostly used to measure the impact of disturbance oncommunity structure [51] while the geometric series (aproposed SAD model) represents species distribution withlower evenness and provide a good fit to simple communitiescharacterized by the high dominance of a few species [48]The shape of the frequency distribution gives an insight intothe bird diversity of the communities under study

Individual-based rarefaction technique [52] was usedto compare bird richness across the four habitats (rarefac-tion curves) Rarefaction curves are created by randomlyresampling the pool of 119873 samples multiple times and thenplotting the average number of species found in each sample(1 2 119873) [53] Thus rarefaction generates the expectednumber of species in a small collection of 119899 individuals (or 119899samples) drawn at random from the large pool of119873 samplesThe rarefaction curve 119891119899 is defined as

119891119899 = 119864 [119883119899] = 119870 minus (119873119899)minus1 119896sum119894=1

(119873 minus 119873119894119899 ) (1)

[52] where 119883119899 is the number of groups still present in thesubsample of ldquo119899rdquo less than 119870 whenever at least one group ismissing from this subsample 119873 is total number of items 119870

is total number of groups and119873119894 is total number of items ingroup 119894 (119894 = 1 119896) [53 54] Therefore the linear model forthe GS was fitted for each rarefied run in order to build the95 confidence limits for the slopes of woodlands

Rarefaction methods both sample-based and individual-based allow for meaningful standardization and comparisonof datasets [51] and have been used on bird counts [eg [55]]

Finally Renyi diversity ordering approach [56] wasapplied to quantify and compare current bird diversitystatus among the habitats following initial analysis thatresulted in various diversity indices Thus Renyi diversityordering has the ability to harmonize the different tech-niques and indices developed for biodiversity analysis (egBerger-Parker Shannon-Wiener and Simpsonrsquos 1-D diversityindices) that makes it complex to select the right toolfor comparing biodiversity measurements [48] Renyi [56]extended the concept of Shannonrsquos entropy [57] by definingthe entropy of order 120572 (120572 ge 0 120572 = 1) of a probabilitydistribution (1199011 1199012 119901119904) Diversity profile values (H-alpha)were calculated from the frequencies of each componentspecies (proportional abundances 119901119894 = abundance of speciesi total abundance) and a scale parameter (120572) ranging fromzero to infinity as

(119867120572) = (logsum119904119894minus1 119901119894120572)(1 minus 120572) (2)

[58] All analyses of bird abundance richness and diversityordering were performed using PAST ver 306 softwarepackage [59] which contains robust algorithm as indicatedin Krebs [60]

A priori test for normality of data distribution was carriedout using Shapiro-Wilk test This was to determine theappropriate statistical test to subject data (ie parametric ornonparametric data analysis approach) [61] Kruskal-WallisH test (a rank-based nonparametric test approach) was thenused to determine if overall bird abundance significantlydiffered among the four communities MannndashWhitney U testpairwise comparison was applied to test for differences inbird richness among the four communities A paired 119905-testwas used to test for significant differences in bird abundancerichness and evenness distribution between the wet anddry seasons using GraphPad Prism 5 statistical software forWindows Canonical correspondence analysis (CCA) [62]was performed to determine the drivers of habitat qualityand its influence on bird preference using ECOMexe ver 14[63] CCA is a direct method of ordination with the resultingproduct being the variability of the environmental data aswell as the variability of species data [61]

4 Results

41 Species Abundance and Structural Distribution Shapiro-Wilk test showed that data were not normally distributed(p = 083) A total of 4951 individual birds belonging to 131species were identified across the four habitat types in thewet (119899 = 3033) and dry (119899 = 1648) seasons (Table 1) Majorityof birds were detected in the woodland habitat (dry season= 557 wet season = 981) while grassland habitat was the


Table 1 Mean number of birds counted at each sampling point count (SPC) across the four habitat types in the wet (n = 3033) and dry (n= 1648) seasons

No of individuals SPC 1 SPC 2 SPC 3 SPC 4Dry season

Woodland 557 73plusmn12 68plusmn102 67plusmn11 58plusmn11Grassland 262 30plusmn085 28plusmn021 36plusmn033 31plusmn004Shrubland 536 60plusmn108 63plusmn12 71plusmn04 59plusmn105Riparian zone 293 41plusmn106 35plusmn13 32plusmn09 31plusmn19

Wet seasonWoodland 981 74plusmn14 85 plusmn19 81plusmn16 86plusmn13Grassland 447 34plusmn21 47plusmn15 28plusmn17 35plusmn13Shrubland 927 81plusmn22 74plusmn147 82plusmn11 69plusmn104Riparian zone 678 61plusmn04 49plusmn18 63plusmn16 51plusmn007

Table 2 Results of the geometric series model for the abundance rank distribution of birds of Mole National Park calculated for WoodlandGrassland Shrubland and Riparian habitats Levels of significant difference (P-values) were shown with superscript alphabet (a )

Dry seasonSample Intercept plusmnSE Slope plusmnSE 1198772 ProbWoodland 4169plusmn110 -0158plusmn009 -019 011Grassland 6760plusmn086 -0122plusmn009 -018 020Shrubland 8319plusmn093 -0292plusmn008 -036 00007aRiparian 3551plusmn099 -0009plusmn008 -001 091Slope of SAD F380= 653 p (regr) 00005

Wet seasonWoodland 1824plusmn082 0231plusmn007 028 0001aGrassland 7501plusmn087 0043plusmn011 028 0001aShrubland 5816plusmn103 022plusmn008 022 001aRiparian 3856plusmn097 021plusmn008 023 001aSlope of SAD = F3117 = 732 p(regr) = 00001

least recorded (dry season = 262 wet season = 447) Meanbird abundance varied significantly (119867119888 = 2172 plt00007Kruskal-Wallis H test) in the dry season and ranged between73 plusmn SE 12 and 58 plusmn11 in the woodland community and 36plusmn SE 03 and 28 plusmn 021 in the grassland community The wetseason also showed significant difference in bird abundanceamong the four communities (119867119888= 2774 plt00004Kruskal-Wallis H test) and ranged between 86 plusmn SE 13 and 74 plusmn 14 inwoodland habitat and 47 plusmn SE 15 and 28 plusmn 17 in grasslandhabitat (Table 1) Species abundance distribution (SAD) fittedwell in the geometric series distribution (GS) model andshowed a general significant difference in the dry (119865380=6534119901 (regr) = 00005ANCOVA interactions x species rank)and wet (1198653117 = 732 119901(regr) = 00001 ANCOVA interactionsx species rank) (Figures 2 and 3 Table 2) However fromindividual habitats we observed significant variations inbird abundance along the slopes of the SAD curve in theshrubland habitat (slope [119896] = -0292plusmn008 1198772 = -036 1205942119875= 00007) while grassland (119896 = -0122plusmn0091198772 = -018 1205942119875 =020) and riparian habitats (119896 = -0009plusmn008 1198772 = -001 1205942119875= 091) did not show any significant variations in abundancein the dry season (Table 2 Figure 2) Although in the wetseason bird abundance generally varied across the habitats

woodland (119896 = 0231plusmn007 1198772 = 028 1205942119875 = 0001) andgrassland (119896 = 0231plusmn007 1198772 = 028 1205942119875 = 0001) habitatsrevealed the highest variations in bird abundance (Table 2Figure 3) Comparison of SADs for the four sites allows forthe distinguishing of a particular habitat quality in relationto its influence on bird abundance Thus the shape of therank abundance curve generally revealed differences in birddominance and evenness from individual habitats whichindicate their relative success at competing for food andspace

Bird community assemblages across the four habitatsrevealed that species were ranked from the most abundantto the least abundant (Figures 2 and 3) Thus fewer thansix species (Sahel Bush-sparrow Gymnoris dentata Longed-tail Glossy Starling Lamprotornis caudatus Northern Black-flycatcher Melaenornis edolioides European pied flycatcherFicedula hypoleuca Senegal Eremomela Eremomela pusillaand Vinaceous dove Streptopelia vinacea) were the mostabundant and detected in all four habitats during the wet sea-sonThese species constituted 495 of the total sampled (119899=121) In the dry season the habitat preferences of these specieswere rather limited as they did not occur in all habitats SahelBush-sparrow Gymnoris dentata (a typical resident bird) was


Woodland habitatGrassland habitat

Riparian habitatShrubland habitat

Figure 2Geometricmodel for bird rank abundance distribution across the four habitats inMoleNational Park in the dry season Abundanceis based on cumulative cover values per species per test site Notice that SADs are ordered in a decreasing magnitude and plotted against thecorresponding rank in this order

the most abundant during the dry (119899 = 69) and wet (119899 =86) seasons with a least concern (LC) conservation statusSenegal Eremomela Eremomela pusilla (119899 = 79 a typicalinsectivorous bird) was the second most abundant speciesacross the four habitats but was only detected in the wetseason The occurrence of this species during the wet seasonwas expected as they mostly feed on insects Rarer specieslike theNorthernGround-hornbillBucorvus abyssinicus wasthe least ranked on the SAD curve in the grassland (119899 =4 dry season) while Bateleur Terathopius ecaudatus (119899 =1)and Wooly-necked stock Ciconia episcopus (119899 =1) with aconservation status of near threatened (NT) and vulnerable(VU) respectively were the least ranked in the woodland andshrubland habitats in the wet season (Figure 3 Appendix 1)These species including a few rarer species with conservationconcern (eg White-backed Vulture Gyps africanus (NT)andWhite-headed Vulture Trigonoceps occipitalis (CR) wereconfined to less disturbed sections in the woodland habitat

Helmeted Guinea fowl Numida meleagris (119899 = 45) wasthe single most dominant species in the dry season which

reflects on its ability to withstand harsh environmentalconditions (eg bushfire) that are common in this time ofthe year Oriole warbler Hypergerus atriceps (n = 4) andYellow-fronted Tinkerbird Pogoniulus chrysoconus (n = 4)were the least ranked species in the riparian zone and onlyencountered in the wet season They were mostly confined toareas of where insects and fruit-bearing trees were abundant

42 Seasonal Trends in Bird Richness across the Four Habi-tats Interpolating SADs in the four habitats with sample-based rarefaction we observed a significant increase in birdrichness from dry to wet seasons (119905-test = -959 plt0002)(Figure 4) We found bird richness in the dry season tobe the highest in the shrubland habitat (119899 = 40) whilein the wet season it was the woodland habitat (119899 =73)(Figure 4) Grassland habitat consistently recorded lowestspecies richness in both dry (119899 = 14) and wet (119899 = 35)seasons Comparing bird richness among habitats in the dryseason revealed shrubland habitat as the richest comparedto those from grassland (119905-test = 275 plt0006) and riparian


Woodland habitat Grassland habitat

Shrubland habitatRiparian habitat

Figure 3Geometricmodel for bird rank abundance distribution across the four habitats inMoleNational Park in thewet season Abundanceis based on cumulative cover values per species per test site Notice that SADs are ordered in a decreasing magnitude and plotted against thecorresponding rank in this order

habitats (119905-test = 257 plt0011) but showed no variation withwoodland preferred species (119905-test = -019 p = 084) In thewet season we equally observed similar significant variationsin bird richness between the woodland and grassland (119905-test =447 plt000012) and riparian habitats (119905-test = 237 plt0018)However bird richness from woodland and shrubland habi-tats showed no significant difference (119905-test = 0078 p= 094)

43 Bird Diversity Profiles across the Four Habitats Theobserved differences in bird community structure (ie abun-dance evenness and richness) are shown in the Renyidiversity ordering (Figure 5) Generally the Renyi diversitycurves showed a clear tight bend towards lower values ofthe diversity index and higher alpha scale values Althoughbird diversity did not differ significantly in the dry (Hc =0087119901=083 Kruskal-Wallis test) andwet (119867119888= 017119901=098Kruskal-Wallis test) seasons the profile diversity of species

from the grassland habitat appeared marginally high in thetwo seasons This observation was linked to the shallowernature of the SAD curves (Figures 2 and 3) and clearlyreflected in the Renyi ordering (Figure 5) although speciesabundance and richness (individual-based rarefaction) werethe least in this habitat Grassland species showed a high-profile alpha (120572) values 004 and 396 which correspondedto diversity indices of 199 and 151 (dry season) and 199and 139 (wet season) respectively These diversity indices areindicative of sites in the habitats that were richer in speciesand spatially even distribution

Woodland and shrubland appeared highly similar indiversity profile and were the lowest especially in the wetseason where the two habitats could barely be distinguishedfrom lower to higher 120572 scale values The 120572 values of these twohabitats ranged between 004 and 396 with correspondingdiversity indices of 1980ndash132 (Woodland) and 1981-133


Dry seasonWet season

Figure 4 Standardized comparison of species richness for two individual-based rarefaction curves The data represent summary counts ofbirds that were recorded from the four habitats in Mole National Park The green red turquois and blue lines are the rarefaction curvescalculated from (1) [53] with a 95 confidence intervalThe dotted vertical lines illustrate a species richness comparison standardized to 262(dry season) and 447 (wet season) individuals which was the observed bird abundance in the smallest (grassland) of the four habitats birddata sets

Dry season Renyi diversity ordering

Wet season Renyi diversity ordering

Figure 5 Renyi diversity ordering that compares bird evenness and richness for the dry and wet seasons across the four habitats Notice thatthe shape of the curve of each habitat is an indication of their spatial evenness of species and ordered from the lowest to highest diversity

(shrubland) (Figure 5) These diversity values revealed theirclose similarity in richness and the proportion of the mostabundant species Overall we found that the relationshipbetween 120572 values and diversity indices especially at highinfinities (120572 gt infin) across the four habitats had lowproportion of diversity indices and dominant species

44 Environmental Predictors of Bird-Habitat Preference TheCCA ordination diagrams present summarized informationon bird structural assemblages mediated by environmentalfactors across the four habitats For the dry season CCA

ordination revealed a strong species-environment correlationon axes I and II where bushfire (r = -0836 plt00001)and erosion (119903 = 0638 plt00001) affected the abundanceand richness of grassland and riparian preferred speciesrespectively (Figure 6 Table 3) However in the shrublandand woodland habitats majority of species like Palm-NutVulture Gypohierax angolensis White-Backed Vulture Gypsafricanus and Brown-Capped Babbler Pellorneum fusco-capillus tended to be attracted to postincidences of bushfirecharacterized by left-over carcass Rarer species like White-backed Vulture Gyps africanus (CR) were impacted by this


Habitat types

Bird species

Environmental disturbances

Figure 6 Canonical correspondence (CCA) ordination diagram showing the relationship between environmental disturbances and birdspecies across the four habitat types in the dry season The arrows represent each of the environmental variables plotted pointing in thedirection of maximum change of explanatory variables across the four habitats

disturbance in terms of limited distribution Species likeSpur-winged lapwing Vanellus spinosus and Namaqua doveOena capensis responded to patchiness and animal trampling(119903 = 089 plt00001 axis I) in portions along the riparianzone (Figure 6 Tables 3 and 4) Overall axes I and II jointlyaccounted for 8182 variance in bird diversity across the fourhabitats (Figure 6 Table 3)

In the wet season bird structural assemblages generallyshowed an increase in bird richness and spatial distributionacross the four habitats (Figure 7) in spite of the strongcorrelation between species-environmental factors on axis I(ie patchiness 119903119901 = 085) and II (ie animal trampling119903119901 = 088) (Figure 7 Table 5) These two axes (5856 andaxis 346) jointly explained 6202 of variability of birdassemblages caused by the environmental factors (Table 5)While species richness from grassland habitat were notablylowest and affected by erosion condition (following previousanimal trampling activities 119903 = -0951 plt00001) (Figure 7Table 6) species from the remaining three habitats rathershowed more tolerant to patchiness and animal tramplingconditions Example included Brucersquos pigeon (Treron waalia)African grey Hornbill (Tockus nasutus) in the woodland

Table 3 Summary of canonical correspondence analysis (CCA) ofbirds showing the levels of correlation between axes and environ-mental gradients variance of species and species-environmentalrelationships in the dry season

Axis I Axis IICanonical Eigenvalue 0912 0418Cumulative variance 8122 06 variance explained 8182 113Pearson corr coefficient speciesenvscore 0976 0990

Kendall rank corr of speciesenv score 0666 0666Correlations(1) Patchiness 0101 -0003(2) Erosion 0638 -0215(3) Animal trampling 0474 0128(4) Bushfire -0836 0140

Red-Billed Hornbill (Tockus erythrorhynchus) and Yellow-Crowned Gonolek (Laniarius barbarus) and Bush petroniaSahel Bush-sparrow (Gymnoris dentata)


Table 4 Intercorrelations (Pearson) between the environmental variables (soil erosion animal trampling tree felling bushfire andpatchiness) in bird dataset during the dry season A correlation abovebelow plusmn061 is significant at p = 00013lowastlowastlowast plusmn045 at p = 001lowastlowastand plusmn033 at p = 005lowast

Patchiness Erosion Animal trampling BushfirePatchiness 1 -0588 0891 -0523Erosion -0588 1 -0296 -0370Animal trampling 0891 -0296 1 -0756Bushfire -0523 -0370 -0756 1

Table 5 Summary of canonical correspondence analysis (CCA) of birds showing the levels of correlation between axes and environmentalgradients variance of species and species-environmental relationships (wet season)

Axis 1 Axis 2Canonical Eigenvalue 0273 0016Cumulative variance 5856 6202 variance explained (6202) 5856 346Pearson corr coefficient speciesenvscore 0854 0880

Kendall rank corr of speciesenv score 0333 0666Correlations(1) Patchiness 0669 0235(2) Erosion 0490 0705(3) Animal trampling 0375 0789

Habitat types

Bird species


Figure 7 Canonical correspondence 773 (CCA) ordination diagram showing the relationship between environmental disturbances andbird species across the four habitat types in the wet season The arrows represent each of the environmental variables plotted pointing in thedirection of maximum change of explanatory variables across the four habitats


Table 6 Intercorrelations (Pearson) between the environmentalvariables (soil erosion animal trampling tree felling bushfire andpatchiness) in bird dataset during the wet season A correlationabovebelowplusmn061 is significant at p= 0001lowastlowastlowastplusmn045 at p = 001lowastlowastand plusmn033 at p = 005lowast

Patchiness Erosion Animal tramplingPatchiness 1 -0336 0028Erosion -0336 1 -0951Animal trampling 0028 -0951 1

The change in the longitudinal profile of species assem-blages from the four habitats (Figures 6 and 7) reflects similartrend observed in previous analysis in SAD curves andindividual rarefaction outcomes (Figures 2 3 and 4)

5 Discussion

Several studies have shown that vegetation habitat typeplays a critical role in structuring bird communities [3132 64 65] This was confirmed in our findings wherewoodland and shrubland habitats supported highest birdabundance and richness probably due to vegetation coverfor nestingsheltering availability of food and less predationaccessibility Despite the high abundance and richness ofbirdsrsquo in the woodland and shrublands overall impact ofbushfire occurrence affected bird diversity therein This wasprobably due to their uneven distribution especially duringthe dry season where food resources and quality nesting siteswere limitedThis scenario tended to increase bird competingfor these resources at sections of the habitats where they arefound leading to their uneven spatial distribution Speciesevenness distribution is considered as one of the keymeasuresof diversity in ecosystems and has been used by manyscientists [eg [66 67]] to quantify biodiversity

Observed variations in bird assemblages suggest theirattraction to habitat-specific which is influenced by eitherevolution or environmental modifications in Mole NationalPark Birds like White-shouldered Black tit Melaniparusguineensis Senegal batis Batis senegalensis and Yellow-fronted Canary Crithagra mozambicus that were foundnesting on selected thorny woody species like Ziziphus mau-ritiana probably did so to seek protection from predationThe dominance of Sahel Bush-sparrow Gymnoris dentataand Senegal eremomela Eremomela pusilla in the dry andwet seasons was probably because of their broad rangehabitat preferences and their ability to adapt to environmentalconditions inherent across these habitats These species couldbe used as indicators of habitat quality if future scenariosrestrict their movement or distribution in narrow rangehabitats Sekercioglu [68] reported that birds encounteredin various habitats types indicate their tolerance to a widerange of ecological conditions More so their populationsize usually depends on the availability of food variableclimate and the interactions among the other factors of theenvironment like human interactions nest predation anddiseases [14]

Bird abundance decline in the dry season especiallyamong grassland associates compared with the remainingthree habitats was probably due to frequency and intensityof bushfires in this habitat which tended to affect foodavailability reduced vegetation cover meant to provide shel-ter and support for bird nest and increased in predationaccessibility (due to less ground cover) The relatively lessimpact of bushfire on birds in woodland and shrublandhabitats including rarer species like Wooly-necked stockCiconia episcopus andWhite-backed Vulture Gyps africanus(NT) with high conservation concern was probably due toless amount of fuel load early vegetation sprout followingburning (which is used as amanagement tool to either reducefuel load or encourage early vegetation growth) and left-overcarcass The survival of these species following postbushfireoccurrence suggests the critical role that woodland andshrublands habitats play in their functional life stages Thesenear threatened or vulnerable conservation status of thesebirds as a result of anthropogenic disturbances may havegradually developed adaptive strategies using their proximatecues (ie genetic and sensory mechanisms) to survive intheir transformed habitats

Studies in Northern Region of Ghana revealed howbushfire affected bird population in off- reserves particularlyin the dry season [69] Sallabanks Walters and Collazo[70] also reported bird postmortality following bushfiresDespite the adverse effects of bushfire and patchiness onbirds observed in this study other studies rather detectedan increase in the abundance of some species like uplandsandpipers (Bartramia longicauda) and yellow billed kiteMilvus aegyptius following burning and grazing activities[70] These varied responses of birds to bushfires may be dueto their tolerance or resilience level at different burning fre-quency and intensity Other environmental factors namelypredation and food scarcity [71] farming practice and urbandevelopment [72ndash74] habitat fragmentation [72 75] cuttingof mangrove vegetation [76] and deforestation [24] havebeen reported to affect bird populations in other ecosystemsRecent reports have shown that birds have gone extinct atan exceptionally high rate estimated to be 1000 to 10000times the natural background rate [16] The InternationalUnion for theConservation ofNature (IUCN) ldquoRedListrdquo havealso shown documented evidence that rate of extinction isgetting worse among species from small islands across theglobe Thus the least birds recorded in the grassland habitatpartly explained that grassland associate birds aremore proneto bushfire outbreak because of the relative quantity of fuelload and ease of burn than the woodland shrubland riparianvegetation

Notwithstanding the least number of birds per species ingrassland Renyi diversity profile rather showed this habitatto be the most diverse in both seasons Ricotta and Avena[66] and Dazzo et al [67] reported that shallower decliningslopes (an indicator of high diversity communities) are moreevenly distributed that steep slopes Thus the shape of theRenyi diversity profiles is influenced by their evenness [77]

Prediction of future bird-habitat specific preference maybe possible because demographic effect of habitat hetero-geneity will be modified by habitat-selection behaviors since


the subset of habitats that are actually used will determinethe populationrsquos demographics [78] Therefore bird-floristichabitat preference in Mole National Park could help predictthe spatiotemporal to long-term distribution and abundanceof birds

6 Conclusions

Generally bird species in Mole National Park were moreassociated with woodland and shrubland habitats and thisis reflected in the outcomes of the SAD and individualrarefaction analyses However variations in bird structuralassemblages suggest their attraction to habitat-specific andmediated by environmental disturbances like bushfire patch-iness and animal trampling We also observed seasonalityinfluence on bird abundance and richness dynamics andlinked the high abundance in the wet season to availabilityof food and vegetation cover against predation Rarer specieswith high conservation concern (eg White-headed VultureTrigonoceps occipitalis (CR) Wooly-necked stock Ciconiaepiscopus (VU) and White-backed Vulture Gyps africanus(NT)) in the woodland and shrubland habitats suggest theneed to intensify conservation of woodland habitats throughcontrol of bushfires reduction of fuel load and limit elephantdestruction of vegetation Limitation of elephant destructionof these two habitats can be done by constructing morewatering holes in the Park to sparsely distribute the elephantpopulation throughout the reserve The resultant effect willlead to reducing pressure on the few watering holes foundin the woodland and shrubland habitats These interventionscould contribute to increasing bird abundance richness andtheir spatial even distribution

Data Availability

The data used to support the findings of this study areavailable from the corresponding author upon request

Conflicts of Interest

The authors declare that there are no conflicts of interestwhatsoever regarding the publication of this research article

Acknowledgments

The authors are grateful to the park rangers and tour guidesat Mole National Park for their assistance during field surveyThe study was self-funded by the authors

Supplementary Materials

This can be found in Appendix 1 which describes list of birdspecies identified and their conservation status with respectto the IUCN global ldquo Red Listrdquo database LC = least concernNT = near threatened CR = critical threatened and VU =vulnerable (IUCN 2011) (Supplementary Materials)

References

[1] S C Kendeigh ldquoCommunity Selection by Birds on the Helder-berg Plateau of New YorkrdquoThe Auk vol 62 no 3 pp 418ndash4361945

[2] G Svardson ldquoCompetition and habitat selection in birdsrdquoOikos vol 1 no 2 pp 157ndash174 1949

[3] O Hilden ldquoHabitat selection in birds A reviewrdquo AnnalesZoologici Fennici vol 2 pp 53ndash75 1965

[4] W M Block and L A Brennan ldquoThe habitat concept inornithology Theory and applicationsrdquo Current Ornithologyvol 11 pp 35ndash91 1993

[5] J Verner and M L Morrison Wildlife 2000 Modeling HabitatRelationships of Terrestrial Vertebrates C J Ralph Ed Univer-sity of Wisconsin Press Madison Wis USA 1986

[6] M L Rosenzweig ldquoHabitat selection and population interac-tions the search for mechanismrdquoThe American Naturalist vol137 pp S5ndashS28 1991

[7] S D Fretwell and H L Lucas Jr ldquoOn territorial behaviorand other factors influencing habitat distribution in birds - ITheoretical developmentrdquo Acta Biotheoretica vol 19 no 1 pp16ndash36 1969

[8] S D Fretwell Populations in Seasonal Environments PrincetonUniversity Press Princeton NJ USA 1972

[9] J R Karr and K E Freemark ldquoHabitat selection and environ-mental gradients dynamics in the lsquostablersquo tropicsrdquo Ecology vol64 no 6 pp 1481ndash1494 1983

[10] H R Pulliam and B J Danielson ldquoSources sinks and habitatselection a landscape perspective on population dynamicsrdquoTheAmerican Naturalist vol 137 pp S50ndashS66 1991

[11] L J Petit andD R Petit ldquoFactors governing habitat selection byprothonotary warblers field tests of the fretwell-lucasmodels 1rdquoEcological Monographs vol 66 no 3 pp 367ndash387 1996

[12] T E Martin ldquoNest predation and nest sitesrdquo Bioscience vol 43no 8 pp 523ndash532 1993

[13] H Poysa J Elmberg K Sjoberg and P Nummi ldquoHabitatselection rules in breeding mallards (Anas platyrhynchos) Atest of two competing hypothesesrdquoOecologia vol 114 no 2 pp283ndash287 1998

[14] J Davis E Rocky T Hall et al Diet differentiation and habitatselection of birds in forested and clear-cut areas 2000

[15] G Caughley ldquoDirections in conservation biologyrdquo Journal ofAnimal Ecology vol 63 no 2 pp 215ndash244 1994

[16] Birdlife International Threatened Birds of the World LynxEditionsBirdlife International Barcelona Spain 2011

[17] J R Herkert ldquoThe effects of habitat fragmentation on midwest-ern grassland bird communitiesrdquo Ecological Applications vol 4no 3 pp 461ndash471 1994

[18] D J Twedt and C R Loesch ldquoForest area and distribution inthe Mississippi alluvial valley implications for breeding birdconservationrdquo Journal of Biogeography vol 26 no 6 pp 1215ndash1224 1999

[19] H R Pulliam ldquoSources sinks and population regulationrdquo TheAmerican Naturalist vol 132 no 5 pp 652ndash661 1988

[20] T E Martin ldquoAremicrohabitat preferences of coexisting speciesunder selection and adaptiverdquo Ecology vol 79 no 2 pp 656ndash670 1998

[21] J D Brawn S K Robinson and F R Thompson III ldquoThe roleof disturbance in the ecology and conservation of birdsrdquoAnnualReview of Ecology and Systematics vol 32 pp 251ndash276 2001


[22] C L Seymour and R E Simmons ldquoCan severely fragmentedpatches of riparian vegetation still be important for arid-landbird diversityrdquo Journal of Arid Environments vol 72 no 12 pp2275ndash2281 2008

[23] G M Siriwardena S R Baillie S T Buckland R M FewsterJ H Marchant and J D Wilson ldquoTrends in the abundanceof farmland birds A quantitative comparison of smoothedCommon Birds Census indicesrdquo Journal of Applied Ecology vol35 no 1 pp 24ndash43 1998

[24] J R Krebs J DWilson R B Bradbury and G M SiriwardenaldquoThe second silent springrdquo Nature vol 400 no 6745 pp 611-612 1999

[25] W R L Cresswell J MWilson J Vickery P Jones and S HoltldquoChanges in densities of Sahelian bird species in response torecent habitat degradationrdquo Ostrich vol 78 no 2 pp 247ndash2532007

[26] J A Veraart R S de Groot G Perello N J Riddiford andR Roijackers ldquoSelection of (bio) indicators to assess effects offreshwater use inwetlands a case study ofAlbufera deMallorcaSpainrdquo Regional Environmental Change vol 4 no 2-3 pp 107ndash117 2004

[27] T R Shankar Raman G S Rawat and A J T JohnsinghldquoRecovery of tropical rainforest avifauna in relation to veg-etation succession following shifting cultivation in Mizoramnorth-east Indiardquo Journal of Applied Ecology vol 35 no 2 pp214ndash231 1998

[28] N Chettri E Sharma and D C Deb ldquoBird communitystructure along a trekking corridor of Sikkim Himalaya Aconservation perspectiverdquo Biological Conservation vol 102 no1 pp 1ndash16 2001

[29] T R Shankar Raman ldquoEffect of slash-and-burn shifting cul-tivation on rainforest birds in Mizoram Northeast IndiardquoConservation Biology vol 15 no 3 pp 685ndash698 2001

[30] G Fanelli and C Battisti ldquoRange of species occupancy distur-bance and generalism Applying hemeroby metrics to commonbreeding birds from a regional Atlasrdquo Vie et Milieu ndash Life andEnvironment vol 65 no 4 pp 243ndash250 2015

[31] A P Gabbe S K Robinson and J D Brawn ldquoTree-speciespreferences of foraging insectivorous birds Implications forfloodplain forest restorationrdquo Conservation Biology vol 16 no2 pp 462ndash470 2002

[32] S L Earnst and A L Holmes ldquoBird-habitat relationships ininterior Columbia Basin shrubstepperdquo Condor vol 114 no 1pp 15ndash29 2012

[33] SMCaziani andEDerlindati ldquoAbundance andhabitat ofHighAndes Flamingos in Northwestern ArgentinardquoWaterbirds vol23 pp 121ndash133 2000

[34] L A Brennan and M L Morrison ldquoLong-term trends ofchickadee populations inWesternNorth AmericardquoTheCondorvol 93 no 1 pp 130ndash137 1991

[35] A L Skowno andW J Bond ldquoBird community composition inan actively managed savanna reserve importance of vegetationstructure and vegetation compositionrdquo Biodiversity and Conser-vation vol 12 no 11 pp 2279ndash2294 2003

[36] R C MacNally ldquoAn analysis of density responses of forestand woodland birds to composite physiognomic variablesrdquoAustralian Journal of Ecology vol 15 no 3 pp 267ndash275 1990

[37] E Acquah PDearden andR Rollins ldquoNature-based tourism inMole National Park Ghanardquo African Geographical Review vol35 no 1 pp 53ndash69 2016

[38] F Dowsett-Lemaire and R J DowsettOrnithological Surveys inMole National Park 2004

[39] T L Hamer C H Flather and B R Noon ldquoFactors associatedwith grassland bird species richness The relative roles of grass-land area landscape structure and preyrdquo Landscape Ecologyvol 21 no 4 pp 569ndash583 2006

[40] Mole National Park (MNP)Management Plan 2011[41] K Schmitt and M Adu-Nsiah ldquoForest resource management

project GWDIUCNrdquo The Vegetation of Mole National Park1993

[42] C BibbyND Burguess andD AHill Bird Census TechniquesAcademic Press London UK 1992

[43] W J Sutherland Ecological Census Techniques A HandbookCambridge University Press 2006

[44] R L Hutto S M Pletschet and P Hendricks ldquoA fixed-radiuspoint countmethod for nonbreeding and breeding season userdquoThe Auk vol 103 no 3 pp 593ndash602 1986

[45] N Borrow and R Demey Field Guide to the Birds of Ghana(Helm Field Guide) A amp C Black Publishers Ltd London UK2010

[46] C Battisti L Luiselli and C Teofili ldquoQuantifying threats in aMediterranean wetland are there any changes in their evalua-tion during a training courserdquo Biodiversity and Conservationvol 18 no 11 pp 3053ndash3060 2009

[47] N Salafsky D Salzer A J Stattersfield et al ldquoA standard lexiconfor biodiversity conservation unified classifications of threatsand actionsrdquo Conservation Biology vol 22 no 4 pp 897ndash9112008

[48] A E Magurran ldquoMeasuring biological diversityrdquo Journal of theTorrey Botanical Society vol 131 no 3 pp 277-278 2004

[49] S Fattorini ldquoA simplemethod to fit geometric series and brokenstick models in community ecology and island biogeographyrdquoActa Oecologica vol 28 no 3 pp 199ndash205 2005

[50] S Fattorini F Rigal P Cardoso and P A V Borges ldquoUsingspecies abundance distribution models and diversity indices forbiogeographical analysesrdquo Acta Oecologica vol 70 pp 21ndash282016

[51] J S Gray and F B Mirza ldquoA possible method for the detectionof pollution-induced disturbance onmarine benthic communi-tiesrdquoMarine Pollution Bulletin vol 10 no 5 pp 142ndash146 1979

[52] N J Gotelli and R K Colwell ldquoEstimating species richnessrdquoBiological Diversity Frontiers in Measurement and Assessmentvol 12 pp 39ndash54 2011

[53] N J Gotelli and R K Colwell ldquoQuantifying biodiversityprocedures and pitfalls in the measurement and comparison ofspecies richnessrdquoEcology Letters vol 4 no 4 pp 379ndash391 2001

[54] A F Siegel ldquoRarefaction curvesrdquo in Encyclopedia of StatisticalSciences K Samuel C B Read N Balakrishnan and BVidakovic Eds 2006

[55] C S Robbins J R Sauer R S Greenberg and S DroegeldquoPopulation declines in North American birds that migrate tothe neotropicsrdquo Proceedings of the National Acadamy of Sciencesof the United States of America vol 86 no 19 pp 7658ndash76621989

[56] A Renyi ldquoOn measures of entropy and informationrdquo inProceedings of the Fourth Berkeley Symposium on MathematicsStatistics and Probability vol 1 pp 1286ndash1291 University ofCalifornia Press Berkeley Calif USA 1961

[57] C E Shannon ldquoA Mathematical Theory of CommunicationrdquoBell System Technical Journal vol 27 no 4 pp 623ndash656 1948

[58] B Tothmeresz ldquoComparison of different methods for diversityorderingrdquo Journal of Vegetation Science vol 6 no 2 pp 283ndash290 1995


[59] O Hammer D A T Harper and P Ryan ldquoPAST paleontolog-ical statistics software package for education and data analysisrdquoPalaeontologia Electronica vol 4 no 1 p 9 2001


[61] M Kent and P Coker ldquoVegetation description and analysisrdquo inA Practical Approach John Wiley and Sons Ltd 1992

[62] C J F Ter Braak ldquoCanonical correspondence analysis a neweigenvector technique for multivariate direct gradient analysisrdquoEcology vol 67 no 5 pp 1167ndash1179 1986

[63] P A Henderson and R M Seaby Environmental CommunityAnalysis 13 Pisces Conservation Ltd Hampshire UK 2000

[64] R A H Draycott A N Hoodless and R B Sage ldquoEffectsof pheasant management on vegetation and birds in lowlandwoodlandsrdquo Journal of Applied Ecology vol 45 no 1 pp 334ndash341 2008

[65] K C Tanalgo J A F Pineda M E Agravante and Z MAmerol ldquoBird diversity and structure in different land-use typesin lowland south-central Mindanao Philippinesrdquo Tropical LifeSciences Research vol 26 no 2 pp 85ndash103 2015

[66] C Ricotta and G C Avena ldquoOn the information-theoreticalmeaning of Hillrsquos parametric evennessrdquo Acta Biotheoretica vol50 no 1 pp 63ndash71 2002

[67] F B Dazzo K J Klemmer R Chandler and Y G Yanni ldquoInsitu ecophysiology of microbial biofilm communities analyzedby CMEIAS computer-assisted microscopy at single-cell reso-lutionrdquo Diversity vol 5 no 3 pp 426ndash460 2013

[68] C H Sekercioglu ldquoForewordrdquo in Handbook of the Birds of theWorld OldWorld Flycatchers toOldWorldWarblers J delHoyoA Elliott and D Christie Eds vol 11 p 48 Lynx EdicionsBarcelona Spain 2006

[69] C A Nsor and E A Obodai ldquoEnvironmental determinantsinfluencing seasonal variations of bird diversity and abundancein Wetlands Northern Region (Ghana)rdquo International Journalof Zoology vol 2014 Article ID 548401 10 pages 2014

[70] R Sallabanks J R Walters and J A Collazo ldquoBreeding birdabundance in bottomland hardwood forests habitat edge andpatch size effectsrdquoTheCondor vol 102 no 4 pp 748ndash758 2000

[71] A F L A Powell ldquoEffects of prescribed burns and bison (Bosbison) grazing on breeding bird abundances in tallgrass prairierdquoThe Auk vol 123 no 1 pp 183ndash197 2006

[72] M Allen Wetlands and Fire Water and Rivers CommissionWater Notes for Wetlands Managers WNS2 Natural HeritageTrust Australia 2000

[73] W J Mitsch and J G GooselinkWetlands JohnWiley amp SonsNew York NY USA 3rd edition 2000

[74] L A Brennan and W P Kuvlesky Jr ldquoNorth Americangrassland birds An unfolding conservation crisisrdquoThe Journalof Wildlife Management vol 69 no 1 pp 1ndash13 2005

[75] L I Jacoboski R K Paulsen and S M Hartz ldquoBird-grasslandassociations in protected and non-protected areas in southernBrazilrdquo Perspectives in Ecology and Conservation vol 15 no 2pp 109ndash114 2017

[76] T J OrsquoConnell L E Jackson and R P Brooks ldquoBird guilds asindicators of ecological condition in the central AppalachiansrdquoEcological Applications vol 10 no 6 pp 1706ndash1721 2000

[77] D Attuquayefio and F Gbogbo ldquoProspects of conservingwetlands along the Mukwe lagoon at Nungua in the greaterAccra region ofGhanardquoWest African Journal of Applied Ecologyvol 2 no 1 2009

[78] W B Kristan III ldquoThe role of habitat selection behaviorin population dynamics Source-sink systems and ecologicaltrapsrdquo Oikos vol 103 no 3 pp 457ndash468 2003

Hindawiwwwhindawicom

Applied ampEnvironmentalSoil Science

Volume 2018

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Volume 2018

AgricultureAdvances in


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quickly to changing habitats [23ndash25] Birds have been usedas surrogates for assessing the impact of habitat changes[26] and considered as good predictors of habitat qualityas they relate to changes that are associated with theirhabitats [27ndash29] Other habitat quality indicators such ashemeroby have widely been used in plant ecology to indicatethe level of disturbance of the optimal habitat for a species[30] Hemeroby is scaled on a range of ten- or five-pointscores higher scores of hemeroby meaning higher level ofdisturbance [30]

Vegetation structure (a typical floristic habitat type) isimportant in structuring avian communities [31 32] andthus their relative abundance is often associated with veg-etation community [33] Vegetative structure is frequentlyassumed to be the primary proximate factor determiningwhere and how species use resources For example SageGrouse (Centrocercus urophasianus) is strongly associatedwith sagebrush (Artemesia tridentata) Chukar (Alectorischukar) is associated with cheatgrass (Bromus tectorum) andChestnut-backed Chickadees (Parus rufescens) appears tofollow the distribution of Douglas-fir (Pseudotsugamenziesii)in California [34] In the Sudan-Guinea Savannah biomeof Ghana where continued habitat loss in protected andunprotected areas is thought to threaten bird survival [25]maintenance of vegetation structure is crucial in sustainingbird population Skowno and Bond [35] observed a stronginfluence of vegetation structure (ie mosaic of trees shrubsand open grassland in mesic African savannas) on bird-habitat use compared to floristic composition HoweverMacNally [36] suggested that floristic habitat relationships ofbirds are often influenced by the scale of observation Mac-Nally [36] concluded that it is important to consider differentobservational scales to determine the relative significance ofstructural and floristic attributes of the habitat

Although tourists have expressed satisfaction at thewildlife attraction (ie large mammals) and the environment[37] bird watching was among the least attractive possiblydue to scanty information about their preferred habitatsborne out habitat transformation Given their important rolein enhancing biodiversity and as bioindicators to ecosystemchange [16 27] birds are among wildlife attractions toMNP and other game reserves across African landscapesThus understanding bird-floristic habitat preference andthe factors that influence their spatial distribution is keyin developing right conservation measures that will sustainbird watching as part of ecotourism drive Though previousstudies have established the presence of diverse avifauna inMNP [38] and are found to be of biogeographical importancethe study did not investigate the habitat preferences and(dis)similarity of bird species assemblage in the variousfloristic habitat types and factors influencing their habitatpreference and spatial distribution The possible mechanismsunderlying the bird species distribution pattern and theuncovering of the possible mechanisms underlying thesepatterns are critical due to the intensity of land use byhumans which continues to alter the availability qualityand distribution of habitats supporting native bird species[39] This study focused on understanding bird communitystructural assemblages as a function of habitat preference and

the predictive factors that influenced their spatial distributionin the MNP in different seasons Thus we hypothesizedthat predictive factors will not alter bird (i) abundanceand richness among habitats (ii) compositional differencesamong habitats (iii) seasonality will not influence changesin abundance and richness and finally (iv) processes thatstructure assemblages in different habitats will not varyamong the habitats along seasonal transition

2 Materials and Methods

21 Study Area The Mole National Park (MNP) where thisstudy was conducted is the largest wildlife reserve in Ghanaand home to a large proportion of Sudan woodland in thenorth of Ghana It is located in the Northern Region of Ghanaand covers an area of 4577 km2 It is one of themajor tourismdestinations in the Northern Region as well as the largestprotected area in Ghana The area lies within geographiccoordinates of 9∘ 111015840 and 10∘ 101015840 N and between 1∘ 221015840 and2∘ 131015840 W and an elevation of 120 to 490 meters above sealevel (Figure 1) Average annual temperature is 28∘C whichvaries from 26∘C in December to 31∘C in March Averageannual rainfall is about 1100 mm decreasing to 1000 mm inthe north of the park [40] The dominant vegetation type inMole National Park is open savanna woodland interspersedwith grasses [41] There are at least 344 different species ofbirds inMoleNational Park and among the key protected sitesin Ghana conserving 37 endemic Sudan-Guinea Savannabiome bird species [40]

22 Sampling Procedure Asurveywas undertakenwithin thestudy area to map out designated vegetation types and thetransect points to use for bird censusWe adopted point countsampling design employed to census birds following Bibbyet al [42] Sutherland [43] and Hutto et al [44] approachin the dry (January-May 2017) and wet (June-October 2017)seasons We counted birds within a 25 m radius surroundingthe observer in four plots covering an area 60 m times 50 m(3000 m2) each in the four vegetation types (ie grasslandwoodland riparian and shrubland) These vegetation typeswere selected because they represented the general vegetationcomposition in Mole National Park The distance betweeneach plot to the other was 100 m and randomly demarcatedBirds that were detected outside the 25 m radius but stillfound within the demarcated boundaries of the plot werecounted and considered as being within the fixed-radius [4244] We chose a 25 m radius because we tended to comparebird abundances evenness distribution and richness amongthe different vegetation types Point count of birds was donetwice in the day the early hours of the morning (from0630-0930 am and in the afternoon (1530-1730 pm)when the temperature is low and most of the birds wereout feeding perching or nesting Flying over birds were notcounted because we assumed that their habitat preferencedid not strongly relate to the vegetation types found in MoleNational Park We avoided performing bird count duringwindy days since visualization of birds might be difficultBird identification was done visually using Birds of Ghanakeys developed by Borrow and Demey [45] and by their calls







3 Data Analysis





119891119899 = 119864 [119883119899] = 119870 minus (119873119899)minus1 119896sum119894=1

(119873 minus 119873119894119899 ) (1)








4 Results







































Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018










3 Data Analysis





119891119899 = 119864 [119883119899] = 119870 minus (119873119899)minus1 119896sum119894=1

(119873 minus 119873119894119899 ) (1)








4 Results







































Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018






3 Data Analysis





119891119899 = 119864 [119883119899] = 119870 minus (119873119899)minus1 119896sum119894=1

(119873 minus 119873119894119899 ) (1)








4 Results







































Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018









































Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018






























Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018






















Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018














Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018





Habitat types

Bird species















Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018










Habitat types

Bird species







5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018








5 Discussion









6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018






6 Conclusions


Data Availability




Acknowledgments




References



















































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018

































































Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018



























Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018






Volume 2018


Journal of





Journal of










Agronomy




Advances in

Virolog y



Geophysics








BotanyJournal of




Volume 2018




Documents

Avian Community Structure as a Function of Season, Habitat ...downloads.hindawi.com/journals/ijecol/2018/2045629.pdf · Habitat Type, and Disturbance, in Mole National Park, Northern