mongooses in Japan - Okinawa and Amami-oshima Island- Office for - PowerPoint PPT Presentation

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 km 2 ) Population: 70,000 Kagoshima Amami-oshima Okinawa Okinawa Island (1,208 km 2 ) Population: 1,200,000 Taiwan 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 Okinawa Is. ( Spilornis cheela perplexus ) ( Scolopax mira ) Yaeyama-group Miyako-group Miyako Is. Iriomote Is. Ishigaki 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 (300km 2 ) • Dr. Watase, the famous biologist （ 2004年） 2004 in Japan was advised by foreign scientists to import mongooses to control poisonous snake Habu and harmful black rat （ 1978年） 1978 • 1990 Released around southern part of Okinawa and settled and spread gradually • 1990s: Expand to Yamabaru O ki naw aw a a I s. region(northern Okinawa) , the (1,206km 2 ) hotspot of wildlife • Mongoose Control measure launched by Okinawa Prefectural Government & MOE launched from 2000 rel eased i n 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 8 FY 2003 FY 2006

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 9 Native species monitoring

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 Amami jay for preventing endemic birds

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 CPUE(Mongooses/100Trap-days) Mongooses CPUE (C/100TD) 800 2,000,000 0.400 Trap-days 619 0.29 573 560 0.27 600 549 1,500,000 0.300 543 520 Okinawa 0.20 396 0.19 0.17 400 1,000,000 0.200 0.16 284 255 208 202 230 200 500,000 0.06 0.100 0.014 0.03 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 rel eased i n 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 am i -oshi m a a I s. • Pest control by local government (712 km 2 ) 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 Ishikawa s frog Amami rabbit Ryukyu long-haired rat Otton frog Amami tip-nosed frog Amami spiny rat 15 Amami Wildlife Conservation Center from 2000 to 2006

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 km 2 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 Bounty trapper 120 • 14,558 mongooses were caught in this five Full time trapper 100 year trapping 2000-2004 80 60 40 20 12 6 4 1 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 AMB 3,000 2,500 2,000 1,500 1,000 500 0 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 2005 2004 2006 2008 2007 2009 22

2012 2010 Log_CPUE (C/1000TD) 100.00 10.00 0.01 0.10 1.00 2001 2002 2003 2004 2011 2005 2006 Year 2007 2008 2009 2010 2011 2012 23

FY2012: 197 mongooses captured In FY2012, 179 mongooses were caught In FY2012, 179 mongooses were caught 37,000 traps are deployed with 2.26 million trap-days. 18 mongooses with 2.26 million trap-days. 18 mongooses were caught with sniffer dogs and handler. were caught with sniffer dogs and handler. Live trap Kill trap Modified kill trap 24

Abundance dynamics of mongooses 10000 Estimated population 推定個体数 Log 10 (Population size) Number of capture 捕獲数 1000 個体数 100 Hierarchical Bayes Model 1980 1990 2000 2010 year 25