Using acoustic monitoring to improve tropical forest

protected area management

Joshua M. Linder

Christos Astaras

Peter H. Wrege

David W. Macdonald

IPS/ASP 2016

(Jenkins and Joppa 2009)

The Problem

Anti-poaching Patrols

The Problem

Where?

When?

A Solution

NkwendeHills

Nigeria

Fun Facts About Korup National Park

• Designated a park in 1986

• 1260 km2

• 15 primate species

• 8 diurnal

• Bushmeat hunting extensive

• Anti-poaching patrols since 1990s

EN

R.

Ber

gl

Drill Preuss’sred colobus

CR

Nigeria-Cameroon

Chimpanzee

EN

Korup N.P.

Mundemba town

Mana bridge

(park entrance)

Locations of acoustic

sensors in Korup

Mana bridge

(park entrance)

What We Did

• 12 ARUs (SM2+ Wildlife Acoustics Inc.)

• June 2013 – May 2015

• 189,000 hrs of sound data

• Scanned with gunshot detection algorithm

verified by humans

• Gunshot detection range = 1.2 km

• Regular patrolling throughout study period

Intensify patrols in “core” ARU area after gathering

baseline gun hunting data

Total detection

area = 54 km2

(assuming 1.2 km detection radius)

0

50

100

150

200

250

300

350

400

450

Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May

What We Found

Year 2: 2,357 gunshots

0.55 shots/day/sensor

Year 1: 2,041 gunshots

0.47 shots/day/sensor

June 2013 – May 2014

June 2014 – May 2015

Ebola reaches

Nigeria Wet Dry Wet

Gunshots

/sensor/

month

What We Found

Market day

What We Found

>68% of gun hunting

occurs at night

Day Night

What we found

Mean gunshots/day/sensor (Year 1)

Mean gunshots/day/sensor

NIGERIA

CAMEROON

Korup NP

What we found

Mean gunshots/day/sensor (Year 2)

Mean gunshots/day/sensor

NIGERIA

CAMEROON

Korup NP

Hunting sign encounter rate vs.

Acoustic monitoring of gunshots

Survey effort = 382.18 km

Hunting signs encountered = 155

Acoustic data

Mean gunshot/sensor/day

P

Q

R

S

Year 2: 2,357 gunshots

0.55 shots/day/sensor

Year 1: 2,041 gunshots

0.47 shots/day/sensor

Average annual gunshots in 54 km2 = 2,199

Extrapolate to all of Korup NP (1,260 km2)

51,310 gunshots annually

Why You Should Care

Korup N.P.

Mundemba town

Hunter and household surveys

Gun hunter success rate = ~74%

Primates = ~14% of gun hunting offtake

17,401 gunshots recorded by hunters during 1 year of hunter surveys

Average annual gunshots = 2,199

Why You Should Care

Gun hunter success rate = 74%Primates = ~14% of gun hunting offtake

1,625 animals killed by gun hunters annually223 primates shot

Estimated Annual Offtake inStudy Area (54 km2)

Estimated Annual Offtake in all ofKorup NP (1,260 km2)

Average annual gunshots = 51,310

Gun hunter success rate = 74%Primates = ~14% of gun hunting offtake

37,918 animals killed by gun hunters annually 5,195 primates shot

Heat map of patrol effortAug. 2014 – June 2015 (7 months in total)

Black circles – detection area of ARUs

Thin red lines – permanent trails/transects

Yellow stars – Tourist camps

Total effort:63 patrol days (mean 5.7 ± 4.7/month)

446.2 km walked(mean 40.6 ± 32.5/month)

On trails: 72%

Off trails: 28%

Night patrols: 1 nightMana bridge

Acoustic monitoring results vs.

actual anti-poaching patrols

• Intensified patrols• Day and night patrols• On and off-trail patrols• Constant presence of patrols

Using acoustic monitoring to design and

evaluate anti-poaching patrols

Improving Anti-Poaching Patrols

In Protected Areas

Funding Provided By:Darwin InitiativeUS Fish and Wildlife ServiceSAVE Wildlife Conservation FundUniversity of Oxford – WildCRUJames Madison UniversityPSMNR

Partners:Korup Rainforest Conservation SocietyCameroon Ministry of Forest and WildlifeKorup National ParkWWF-CameroonPSMNR