The Population size and distribution of critically endangered Hirola Antelope (Beatragus hunteri) in...

The Population size and distribution of The Population size and distribution of critically endangered Hirola Antelope critically endangered Hirola Antelope

((Beatragus hunteriBeatragus hunteri) in Arawale National ) in Arawale National Reserve, KenyaReserve, Kenya

Francis Kamau MuthoniFrancis Kamau MuthoniTerra Nuova East AfricaTerra Nuova East Africa

Transboundary Environmental Transboundary Environmental ProjectProject

25-28 June 200725-28 June 2007 10th SCGIS Conference, Montere10th SCGIS Conference, Monterey, CAy, CA

Hirola ProfileHirola Profile Diet: mostly grassDiet: mostly grass

Weight: 75 - 160 kgWeight: 75 - 160 kg

Mean group size: 7- 8Mean group size: 7- 8

Gestation: 7 monthsGestation: 7 months

Sexually mature: 2 Sexually mature: 2 yearsyears

Habitat: seasonally arid Habitat: seasonally arid region of grassy plains region of grassy plains btwn acacia bush and btwn acacia bush and coastal forestcoastal forest


Study AreaStudy Area

Area: 540 Km2Area: 540 Km2

Only in-situ conservationOnly in-situ conservation

initiative for hirolainitiative for hirola

6 species of conservation 6 species of conservation

interestinterest

Gazetted 1973Gazetted 1973

Protection collapsed 1988Protection collapsed 1988


Historical Range of HirolaHistorical Range of Hirola

38,400 Km38,400 Km22 in Kenya in Kenya and Somalia (1960’s)and Somalia (1960’s)

19,158 Km19,158 Km22 in Kenya in Kenya (1960’s)(1960’s)

Current 9,177 KmCurrent 9,177 Km22

14,000 in 1960’s14,000 in 1960’s

1,000 - 2000 Today1,000 - 2000 Today


Transect Transect MethodologyMethodology

Transects are lined Transects are lined down considering down considering areas of interest or areas of interest or relevancerelevance

Transect counts Transect counts are performed by are performed by moving along the moving along the identified line on identified line on foot/vehiclefoot/vehicle

All observations are All observations are recorded in specific recorded in specific forms and geo-forms and geo-referenced with referenced with GPSGPS

Transect counts are Transect counts are performed on the performed on the same, day and at same, day and at the same time the same time each montheach month


Population Population EstimatesEstimates

Using N= (nZ/T)2W Where: Using N= (nZ/T)2W Where:

N = Population size in the N = Population size in the whole survey zone. whole survey zone. (Dahiye, 1999)(Dahiye, 1999)

n = Population size in n = Population size in transects (monthly transects (monthly average)average)

Z = total area of the Z = total area of the survey zonesurvey zone

T = Length of the transectT = Length of the transect

W= Width of the transect.W= Width of the transect.

Abundance of Hirola Antelope in Arawale National Reserve

0

50

100

150

200

250

300

T1A T2A T4A T5A

Transects

No

. of

Hir

ola

Abundance

N= (45*540/70)0.2


Population Size & Population Size & DensityDensity

Total Sighted: 534Total Sighted: 534

Groups: 87Groups: 87

Mean: 45Mean: 45

Population Size: 69Population Size: 69

Density: 0.13/KmDensity: 0.13/Km22

Mean Groups Size: Mean Groups Size: 6.16.1

Population Size of Hirola in ANR

0

100

200

300

400

500

600

1

Parameters

No.

of h

irol

a Sum

average/Month

Population Size


Seasonal DistributionSeasonal Distribution

Total IndividualsTotal Individuals

-- Dry 59% Dry 59%

-- Wet 41% Wet 41%

Groups Groups SightingsSightings

- - Dry 68%Dry 68% -- Wet 32% Wet 32%

Seasonal distribution of Hirola in ANR

0

100

200

300

400

dry wet

Season

No

./fr

equ

ency

Frequency

Hirola No.

SeasonSeasonss

GroupGroupss

No.No.

DryDry 5959 313313

WetWet 2828 221221

TotalTotal 8787 534534


Distribution of hirola in Distribution of hirola in ANR.ANR.


Habitat PreferencesHabitat Preferences

Habitat Preferences of Hirola in ANR

0

50

100

150

200

250

300

grassland open bush Closed Bush

No

. o

f H

iro

la

Frequency

Hirola No.

HabitatHabitat GroupGroupss

No.No.

GrasslandGrassland 3030 253253

Open bushOpen bush 5757 281281

Closed Closed BushBush

00 00

TotalTotal 8787 534534


Human-Livestock-Wildlife Human-Livestock-Wildlife interfacesinterfaces


Livestock GrazingLivestock GrazingLivestock Species in ANR

0

500

1000

1500

2000

2500

3000

3500

4000

4500

Cattle Shoats Goats Donkey Camel

No

. o

f A

nim

als

Total No.

SpeciesSpecies TotalTotal

Cattle Cattle 4,202 4,202

Shoats Shoats 3,720 3,720

Goats Goats 486 486

DonkeDonkey y

24 24

Camel Camel 2 2

TotalTotal 8,438,4344


ThreatsThreats Habitat degradation Habitat degradation

DroughtDrought

PoachingPoaching

Competition with livestockCompetition with livestock

PredationPredation

InbreedingInbreeding


AcknowledgementsAcknowledgements

Thank YouThank You

Email: [email protected]: [email protected]

The Population size and distribution of critically endangered Hirola Antelope (Beatragus hunteri) in...

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