Appendix S1. The distribution of respondents (n = 362) in 36 locations in and Negeri Sembilan in the western coast of Peninsular On average, the density of respondents at each location was one respondent per 128 ha

Location Coordinates Total Total number Area per planted of respondents respondent area (ha) (ha) Latitude Longitude Conventional plantation Sungai Kelambu 2°45 45 N 101°33 07 E 624 4 156 Bukit Changgang 2°47 37 N 101°39 03 E 267 4 67 Gagasan 3°37 33 N 101°25 23 E 865 3 288 3°38 42 N 101°25 00 E 1529 6 255 3°39 47 N 101°16 14 E 1052 10 105 Soeharto 3°40 52 N 101°21 42 E 2204 23 96 Gedangsa 3°44 52 N 101°21 20 E 1805 4 451 Eco-friendly plantation Sua Betong 2°30 27 N 101°54 13 E 3045 29 105 Bukit Pelanduk 2°36 26 N 101°48 13 E 1770 15 118 Tanah Merah 2°38 31 N 101°48 13 E 4025 22 183 2°41 56 N 101°44 35 E 1378 9 153 Kelanang Baru 2°47 20 N 101°27 24 E 495 6 83 2°48 19 N 101°31 28 E 275 2 138 Sungai Sedu 2°51 17 N 101°32 55 E 974 5 195 2°52 19 N 101°27 42 E 490 2 245 2°53 24 N 101°23 42 E 11 509 29 397 Bukit Cerakah 3°09 25 N 101°23 58 E 1595 4 399 Bukit Kerayong 3°10 45 N 101°23 40 E 2024 3 675 Sungai 3°10 47 N 101°22 42 E 524 6 87 Elmina 3°14 14 N 101°30 26 E 1489 10 149 3°16 28 N 101°22 41 E 506 2 253 3°17 07 N 101°20 39 E 1676 2 838 Monmouth 3°19 32 N 101°21 42 E 594 11 54 Bukit Badong 3°20 39 N 101°26 29 E 246 1 246 Sungai Selangor 3°21 44 N 101°21 44 E 1735 12 145 Raja Musa 3°24 58 N 101°19 38 E 1187 2 594 Hopeful 3°28 03 N 101°27 58 E 718 8 90 Smallholding Kampung Endah 2°43 38 N 101°31 04 E 120 10 12 Sungai Lang Tengah 2°46 51 N 101°29 52 E 75 6 13 Bukit Changgang 2°49 50 N 101°37 21 E 200 17 12 Sungai Terap 3°17 36 N 101°25 54 E 90 9 10 Kampung Raja Musa 3°24 52 N 101°23 12 E 145 12 12 Kampung Tiram Jaya 3°26 46 N 101°14 52 E 180 12 15 Kampung Soeharto 3°41 31 N 101°22 48 E 350 19 18 Merbau Berdarah 3°42 52 N 101°84 29 E 450 27 17 Kampung Gedangsa 3°44 15 N 101°23 11 E 300 16 19

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Appendix S2. Using the following semi-structured questions, we asked 362 oil-palm workers about the causes of wildlife deaths in established oil-palm landscapes and other relevant issues The questions were linked to other relevant questions using the symbol ►

1. Illegal hunting 1.1. Do you hunt any wild animals in oil palm-cultivation areas? (Yes ► 1.3/No ► 1.2).

1.2. What discourages you from hunting wildlife in oil palm-cultivation areas? (► 1.9).

1.3. Why did you hunt these wild animal(s)? (► 1.4).

1.4. What native species have you successfully killed or trapped? (► 1.5).

1.5. How do you usually hunt game animal(s)? (► 1.6).

1.6. When do you usually carry out hunting? (► 1.7).

1.7. How many game animals do you usually catch in a hunting expedition? (► 1.8).

1.8. Are you aware of local wildlife laws or plantation regulations that specifically ban hunting activities? (► 1.9).

1.9. Do you know of any poacher(s) from other areas who may also hunt in this local area? (► 1.10).

1.10. What native species would this external poacher try to hunt? (► 1.11).

1.11. Do you report cases of illegal hunting to the wildlife conservation authority?

2. Road accidents 2.1. Have you found carcasses of wild animals killed in road accidents in oil palm-cultivation areas? (Yes ► 2.2 /No).

2.2. What native species are usually killed by road accidents? (► 2.3).

2.3. How often do you see this type of accident? (► 2.4).

2.4. Do you report such accidents to the wildlife authority?

3. Feral dogs 3.1. Do you encounter any feral dogs in oil palm-cultivation areas? (Yes ► 3.2 /No).

3.2. How many feral dogs do you usually see? (► 3.3).

3.3. What do the feral dogs usually eat to survive in oil palm cultivation areas?

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Appendix S3. Road kills involving native mammals in established oil-palm landscapes in Peninsular Malaysia. (a) Leopard cat, (b) long-tailed macaque, (c) common palm civet and (d) wild boar. Photographs by Badrul Azhar.

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Appendix S4. Recommended measures to control wildlife poaching In addition, to directly reduce hunting pressure, education programs should be developed and promoted in palm-oil landscapes. Such programs could be coordinated by the palm-oil stakeholders, and directed at plantation workers, particularly foreign and poorly educated local workers, as well as those employed in smallholdings. These groups are likely to be unaware of local wildlife laws that prohibit illegal hunting within oil palm-cultivation areas. Integrating oil- palm cultivation with cattle farming may also divert attention away from bushmeat consumption.

Our data suggested that poachers were motivated by the wildlife trade to hunt the Sunda pangolin and monitor lizard, with the majority of poaching activities reported in smallholdings rather than in plantation estates. Although fencing, in combination with security guards, effectively guarded many plantation estates from poachers, armed security officers should not be seen as a panacea to prevent poaching. Perhaps not surprisingly, misuse of firearms by some security guards contributed to illegal hunting in oil-palm plantation estates, despite some plantation companies banning wildlife hunting.

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