<p>1Grant-Hoffman et al.</p><p>ESM1. Islands studied during 2004 and 2005, ‘*’ indicates islands used for within-island analyses. ‘†’ indicates islands for which we did not have whole-island diversity. All islands are located off the North Island of New Zealand. Seabird densities are based on means of two to four 100m2 plots. </p><p>Distan Are ce Seabird Island Latitu Longitu a from Rat Rat density Island abbrevia de de (°E) (ha mainla History Status (burrows/10 tion (°S) ) nd 0m2) (km) Uninvad Uninvad *Ohinauiti OHI 36.71 175.88 5.9 5.3 3.5 ed ed Uninvad Uninvad *Aorangia AOA 35.48 174.71 5.6 21.4 11 ed ed Uninvad Uninvad *Ruamahauiti RTI 36.97 176.06 25.5 18.1 13 ed ed 107. Uninvad Uninvad *Aorangi AOI 35.48 174.72 20.6 17 1 ed ed *Ruamahaun Uninvad Uninvad RNI 36.95 176.09 32.4 19.9 18.5 ui ed ed 158. Uninvad Uninvad *†Tawhiti TR 35.45 174.71 21.7 24.5 Rahi 2 ed ed Uninvad Uninvad *Archway ARY 35.49 174.74 6.3 20.7 38 ed ed Uninvad Uninvad *Middle (Atiu) MID 36.6 175.84 13.5 8.3 68.5 ed ed Uninvad Uninvad Green GRN 34.64 175.85 2.5 7.2 101.5 ed ed Rattus Motukaramar MOA 36.68 175.37 10.1 3.3 norvegic Invaded 0 ama (Bush) us Rattus rattus or Motuoruhi MOI 36.73 175.4 58 2.6 R. Invaded 0 norvegic us Rattus rattus eradicat Motutapere MOE 36.78 175.4 45.6 2.5 Invaded 0 ed 1996, reinvade d Rattus rattus or Pakihi PAK 36.54 175.1 110 1.4 R. Invaded 0 (McCallum) norvegic us Rattus Rakitu (Arid) RAK 36.07 175.3 350 37.6 Invaded 0 rattus Rattus Aiguilles AIG 36.03 175.39 72.7 47.7 Invaded 0.5 rattus Rattus Goat GOT 36.26 174.8 13.4 0.015 Invaded 0.5 rattus</p><p>2 3Grant-Hoffman et al.</p><p>Rattus rattus or *Motueka MOK 36.82 175.8 6.2 1.2 R. Invaded 4 norvegic us Rattus norvegic us eradicat Manage TH 36.51 174.74 6 10.5 0.25 †Te Haupa ed 1989, d Mus musculu s Rattus norvegic us eradicat Manage HAU 37.21 175.89 10.3 0.5 1 †Hauturu ed 1985, d Mus musculu s Rattus norvegic *Motuhoropa us Manage MOP 36.41 174.57 8.6 17.9 2 pa erradicat d ed 1987, 1991 Rattus norvegic us Manage *Otata OTA 36.41 174.58 15 17.5 7 erradicat d ed 1987, 1991 Rattus norvegic Manage *Whenuakura WHE 37.22 175.89 3 0.9 us 15.25 d eradicat ed 1985</p><p>1</p><p>4</p>