Eradication Project of Invasive Alien Mongooses on Amami-Oshima

Home , Okinawa rail, Otton frog, Prionailurus, Small Indian mongoose

Eradication project of invasive alien mongooses in Japan - Okinawa and Amami-oshima Island-

Office for Alien Species Management, Wildlife Division, Nature Conservation Bureau, Ministry of the environment Masato Morikawa

1 Ryukyu Archipelago - one of biodiversity hot spots of the world

Tokyo Amami-oshima Island (712 km2) Population: 70,000 Kagoshima

Amami-oshima Okinawa

Okinawa Island (1,208 km2) Taiwan Population: 1,200,000 2 Ryukyu Archipelago - one of biodiversity hot spots of the world

• Biogeographically, border of Palearctic and Oriental region. • Isolated from the continent about 2 - 1.7 million years ago. c.f. Mainland Japan : isolated about 10 000 – 20 000 years ago. • Many endemic species inhabit with limited predator species Korea

Kyusyu Watase line

Taiwan Islands of poisonous snake, habu 3 Native wildlife in the Ryukyus evolved in the absence of predatory mammals

Amami-group Amami-oshima Is. Tokunoshima Is. Iriomote cat Amami rabbit (Prionailurus bengalensis (Pentalagus furnessi) iriomotensis) Okinawa-group

Crested Serpent Eagle Amami woodcock (Spilornis cheela perplexus) Okinawa Is. (Scolopax mira) Yaeyama-group Miyako-group Miyako Is. Ishigaki Is. Iriomote Is.

Yambaru long-armed Amami thrush Okinawa woodpecker Okinawa rail scarab beetle (Zoothera dauma major) (Dendrocopos noguchii) (Gallirallus okinawae) (Cheirotonus jambar) 4 Small Indian Mongoose (Herpestes auropunctatus)

• A small, slim-bodied predator native to areas from Iran, through India to Myanmar, VietNam. Small Indian mongoose • It has been introduced to many islands to control rats, particularly in sugar cane fields of tropics. • The mongoose has had a major impact on native species in the areas where it has been introduced.

5 100 of the worst invasive alien species by ISSG, IUCN More than 70 islands/areas introduced

(Hays & Conant, 2007) 6 1910: First introduction to Japan

(300km2) • Dr. Watase, the famous biologist （2004年） in Japan was advised by foreign 2004 scientists to import mongooses to control poisonous snake Habu and harmful black rat （1978年）1978 • Released around southern part 1990 of Okinawa and settled and spread gradually • 1990s: Expand to Yamabaru region(northern Okinawa) , the O kinaw a Is. (1,206km2) hotspot of wildlife • Mongoose Control measure launched by Okinawa Prefectural Government & MOE launched from 2000 released in 1910 7 Starting control efforts

• In 2000, the Okinawa Prefectural Government began cull efforts. • In 2005, control efforts began with the enforcement of the Invasive Alien Species Act. • The mongoose population continued to expand until 2006, causing the Okinawa rail population to retreat. • Mongoose proof fence installed in 2006 in SF line to prevent mongooses from spreading north.

SF line

FY 2000 FY 2003 FY 2006 8 Outline of control measures • Control initiatives began with cage-type live traps, which required daily checking. Trappers installed traps along logging roads. • The introduction of tube-type kill traps for which checking frequency can be set as desired (usually every two to four weeks) and the use of kill traps and live traps as required brought about a drastic increase in the number of traps managed. • Trappers began related work in forests in FY 2007.

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 Live trap Forest work Kill trap Sensor cameras Sniffer dogs Native species monitoring 9 Preventing damage of indiscriminate capture • Kill traps were first introduced in 2003 • Deploy endemic rats are absent and/or in low density. Amami spiny rat （Tokudaia ■ Live trap osimensis） …Everyday checking is necessary

…Used in habitat of endangered native species Ryukyu long- haired rat （Diplothrix legata）

■ Kill trap (Pipe- trap) …Efficient (Lightweight, Set for 2-4 weeks) …Birds : discriminable Rats : indiscriminable

Okinawa rail trigger

Simulation and trial to decide trap shape 10 for preventing endemic birds Amami jay Changes in capture status Distribution of mongooses have decreased

Capture number of mongooses Capture number of mongooses Capture number of mongooses Capture number of mongooses 2006 2007 2008 2009 Location of trap installation Location of trap installation Location of trap installation Location of trap installation

Capture number of Capture number of Capture number of mongooses mongooses mongooses 2010 2011 2012 Location of trap installation Location of trap installation Location of trap installation

11 Changes in capture status Mongooses have steadily decreased

1,000 2,500,000 0.500 0.43 Mongooses CPUE(Mongooses/100TrapCPUE (C/100TD) -days) 800 2,000,000 0.400 Trap-days 619 0.29 573 549 560 0.27 600 520 543 1,500,000 0.300 0.20 Okinawa 396 0.19 400 1,000,000 0.200 0.16 0.17 284 255 208 230 202 200 500,000 0.100 0.06 0.03 0.014 0.02 0.016 0 0 0.000

• Since the Yambaru Mongoose Busters started its activities, there has been a drastic increase in the total number of traps (see the line graph). The total number of trap days has kept around 1.5 million every year since 2011. The number of mongooses caught (see the bar graph) has shown a declining trend since 2008, and been a significant drop in the number in recent years. • CPUE, an indicator of mongoose population size, has continued to decrease.

12 1979: Introduction into Amami from Okinawa Island

• There are few records about introduction into Amami • Mongooses were brought in from released in 1979 Okinawa Island (Sekiguchi （2004年） et.al.,2001)

• Mongooses successfully settled on （1990年） Amami and expanded their （2004年） distribution • Damages on farming and poultry gradually appeared from 1983 • Some research by Amami Mammalogical Society from 1989 A m am i-oshima Is. • Pest control by local government (712 km2) began from 1993

14 Strong negative impacts on native vertebrates Partial extinction of mammals and amphibians in range of mongooses ：distribution of native vertebrates ：core area of range of mongooses

Amami rabbit Amami Ishikawa s frog

Ryukyu long-haired rat

Otton frog

Amami spiny rat Amami tip-nosed frog

Amami Wildlife Conservation Center from 2000 to 2006 15 1993-: Pest control by local government

• Pest animal that causes harm to crops and chicks • Local government launched control to reduce damages of crops • Licensed trapper were paid JPY 2,200 for a mongoose • 8,234 mongooses were captured in ⒸAmami city seven years (1993-1999) • Most of them captured around the center of distribution, high density area

16 2000-2004: Control program by bounty trapper

Live trap • At the beginning, mongooses were live trapped by one hundred bounty trappers • To keep incentive to trap, bounty increased from JPY 2,200 (2000) to JPY 4,000 (2001-02) Seminar for and JPY 5,000 (2003-04) bounty trapper • Trapping data of bounty trappers were collected with using standard grid square (about 1 km2 mesh) • A small number of trappers were employed to set traps at low density area and in bushes. 1

trapper in 2002, 4 in 2003, and 6 in 2004 120 Bounty trapper Full time trapper • 14,558 mongooses were caught in this five 100 year trapping 2000-2004 80

20 12 6 1 4 0 17 2000 2001 2002 2003 2004 2005 2005- Organizing Amami Mongoose Busters (AMB)

• Invasive Alien Species Act was enforced in 2005 • MOE launched a mongoose eradication project, hiring trapping experts, “Amami Mongoose Busters (AMB)”. 120 Bounty trapper 100 Full time trapper, AMB 80 60 40 20 0

18 2013: AMB and trained sniffer dogs

19 32,357 mongooses caught in 20 years

4,500 Project by MOE Pest control 4,000 Trapping data set 3,500

3,000 AMB

2,500

2,000

1,500

1,000

500

1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 10,351 mongooses by pest control 22,006 mongooses by MOE project 20 CPUE (Capture/1000trap-days) distribution

FY2001

21 CPUE (Capture/1000trap-days) distribution 2001 2002 2003

2004 2005 2006

2007 2008 2009

22 2010 2011

100.00

2012

10.00

1.00

2009 2012 2001 2002 2003 2004 2005 2006 2007 2008 2010 2011

0.10 Log_CPUE (C/1000TD)

0.01 Year 23 FY2012: 197 mongooses captured

InIn FY2012,FY2012, 179179 mongoosesmongooses werewere caughtcaught 37,000 traps are deployed with with 2.262.26 million million traptrap - - days. days. 18 18 mongooses mongooses werewereLive trap caughtcaught withwith sniffersniffer dogsdogs andand handler.handler. Kill trap Modified kill trap

Abundance dynamics of mongooses

Estimated推定個体数 population

10000 Number捕獲数 of capture

1000

(Population size) (Population

個体数

10 10

Log 100

Hierarchical Bayes Model

1980 1990 2000 2010 year 25

(A) Small Indian mongoose (A) Small Indian mongoose

ycpue.mon

0 0

(B) Black rat (B) Black rat 10

2002:2009 10 2002:2009Fukasawa et al., 2013a

Recovery of native species 1 Proc. R. Soc. B

ycpue.rat.dis ycpue.rat.dis

0 Alien Native 0

(C)(A) AmamiSmall Indian Spiny mongoose rat (C) Amami Spiny rat

15 15 2002:2009 15

2002:2009

days)

ycpue.mon

5 ycpue.toge.nat

0 0

(B)(D) BlackRyukyu rat long-haired rat (D) Ryukyu long-haired rat

2 2

10 2002:2009 2002:2009

CPUE(animals/1000trap

ycpue.rat.dis

ycpue.kenaga.nat

0 0

2002(C) Amami2004 Spiny2006 rat 2008 2002 2004 2006 2008 15 Figure 2. Temporal changes in catch2002:2009 per unit effort . For the rat species, the solid and dashed lines indicate Year the areas of mild (10 habitat alteration index, HAI<0) and 26

intensive (HAI >0) habitat alteration, respectively.

5 ycpue.toge.nat 0 (D) Ryukyu long-haired rat

2 2002:2009

ycpue.kenaga.nat 0 2002 2004 2006 2008 Watari et al., 2013 Recovery of native species 2 Ecology and Evolution

Scientists surveyed the population densities along logging road of four endangered species threatened by the mongoose.

Amami rabbit Amami tip- nosed frog

Otton frog Amami Ishikawa’s frog

Figure 3. Temporal changes in numbers of four species 27 observed per site per survey (mean SE). Probability of eradication success • This simulation shows the current capture efforts of 2010 is the most cost-effective way to eradicate mongooses in this island. The eradication success might be feasible if eradication action same capture efforts of 2010 is continued over the next decade. • However, we think that the most difficult point of eradication of mongooses is one final push (Trapping final 10 mongooses ). Therefore we are also considering alternative measure.

Fukasawa et al., 2013b The eradication feasibility of J. Applied Ecology 1.0 mongooses was estimated 0.8 using trapping data. (see 0.6 black circle which indicate 0.4 0.2 eradication feasibility.) 0.0 7.0 2050 6.5 2040 6.0 2030 5.5 0.0 0.2 0.4 0.6 0.8 1.0 5.0 2020 ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― ― 4.5 28 Eradication action plan by 2022

• New ten year mongoose Monitoring area eradication plan was settled on from FY2013 Priority area to 2022. • The challenges are to eradicate small number of mongooses scattered in a large area, and to ensure that no mongoose survives in every area, with using sniffer dogs, camera traps and hair traps.

http://kyushu.env.go.jp/naha/wildlife/data/gairai/boujyo/130425b.html 29 Education & Awareness Pamphlet for the mongoose eradication measure

30 http://kyushu.env.go.jp/naha/wildlife/data/gairai/boujyo/131017a.pdf Thank you for your attention