New Zealand fur seal demographics

Open Bay Islands, 2023

Mark-recapture estimate, 26–27 Jan 2023

Total marked
368
Mean estimate
637.9
Range
604.1 – 659.8

Mark-recapture counts

Count number Date Time Sector Unmarked count Marked count Dead marked Dead unmarked Total marked Cum. dead Estimate?
1 26 Jan 2023 07:00 – 07:10 Sector 1 2 -
26 Jan 2023 07:10 – 07:25 Sector 2 9 19
26 Jan 2023 07:30 – 07:48 Sector 3 23 30
26 Jan 2023 07:52 – 08:15 Sector 4a 17 20
26 Jan 2023 08:20 – 08:42 Sector 5 13 23
26 Jan 2023 08:42 – 09:02 Sector 6a 21 14
26 Jan 2023 09:02 – 09:10 Sector 6c - 3
26 Jan 2023 09:25 – 09:35 Sector 7a 8 9
26 Jan 2023 09:39 – 09:46 Sector 7b 10 22
All sectors 103 140 - - 368 - 637.6
2 26 Jan 2023 13:11 – 13:14 Sector 1 3 -
26 Jan 2023 12:58 – 13:10 Sector 2 6 17
26 Jan 2023 12:40 – 12:56 Sector 3 13 23
26 Jan 2023 12:25 – 12:33 Sector 4a 6 4
26 Jan 2023 12:11 – 12:25 Sector 4b 8 16
26 Jan 2023 11:45 – 12:11 Sector 5 9 27
26 Jan 2023 11:27 – 11:45 Sector 6a 15 10
26 Jan 2023 11:19 – 11:27 Sector 6b 10 11
26 Jan 2023 11:13 – 11:19 Sector 6c 1 3
26 Jan 2023 10:00 – 10:05 Sector 7a 7 5
26 Jan 2023 10:09 – 10:21 Sector 7b 9 19
All sectors 87 135 - - 368 - 604.1
3 26 Jan 2023 14:27 – 14:28 Sector 1 6 -
26 Jan 2023 14:30 – 14:40 Sector 2 8 21
26 Jan 2023 14:45 – 15:05 Sector 3 10 12
26 Jan 2023 15:05 – 15:30 Sector 4a 5 10
26 Jan 2023 15:30 – 15:44 Sector 4b 5 19
26 Jan 2023 15:45 – 16:10 Sector 5 10 9
26 Jan 2023 17:00 – 17:10 Sector 6a 10 10
26 Jan 2023 16:48 – 17:00 Sector 6b 12 4
26 Jan 2023 16:45 – 16:48 Sector 6c 1 4
26 Jan 2023 10:31 – 10:37 Sector 7a 10 3
26 Jan 2023 10:40 – 10:52 Sector 7b 10 17
All sectors 87 109 - - 368 - 659.8
4 26 Jan 2023 17:45 – 17:46 Sector 1 - -
26 Jan 2023 17:46 – 17:58 Sector 2 10 16
26 Jan 2023 18:03 – 18:20 Sector 3 10 16
26 Jan 2023 18:25 – 18:30 Sector 4a 8 4
26 Jan 2023 18:30 – 18:40 Sector 4b 9 15
26 Jan 2023 18:40 – 18:57 Sector 5 7 18
26 Jan 2023 18:57 – 19:08 Sector 6a 9 9
26 Jan 2023 19:08 – 19:15 Sector 6b 6 7
26 Jan 2023 19:15 – 19:20 Sector 6c 1 -
27 Jan 2023 09:44 – 10:00 Sector 7a 12 3
27 Jan 2023 10:05 – 10:12 Sector 7b 12 19
All sectors 84 107 - - 368 - 655
5 27 Jan 2023 07:10 – 07:12 Sector 1 3 -
27 Jan 2023 07:12 – 07:29 Sector 2 8 18
27 Jan 2023 07:35 – 07:53 Sector 3 20 23
27 Jan 2023 07:58 – 08:10 Sector 4a 5 7
27 Jan 2023 08:10 – 08:25 Sector 4b 3 22
27 Jan 2023 08:25 – 08:57 Sector 5 8 16
27 Jan 2023 08:57 – 09:12 Sector 6a 12 8
27 Jan 2023 09:12 – 09:22 Sector 6b 17 14
27 Jan 2023 09:22 – 09:26 Sector 6c 2 1
27 Jan 2023 10:16 – 10:22 Sector 7a 4 3
27 Jan 2023 10:32 – 10:39 Sector 7b 10 15
All sectors 92 127 - - 368 - 633.2

Dead count, 24–27 Jan 2023

Count
138

Dead counts

Date Sector Fresh Decomposing Dry Count
24 Jan 2023 Sector 2 3 1 1 5
26 Jan 2023 Sector 2 3 - - 3
24 Jan 2023 Sector 3 5 2 4 11
26 Jan 2023 Sector 3 3 - - 3
25 Jan 2023 Sector 4 4 8 8 20
26 Jan 2023 Sector 4 8 - - 8
27 Jan 2023 Sector 4 1 - - 1
25 Jan 2023 Sector 5 1 7 3 11
26 Jan 2023 Sector 5 - - - -
25 Jan 2023 Sector 6 4 5 13 22
26 Jan 2023 Sector 6 5 - - 5
27 Jan 2023 Sector 6 1 - - 1
25 Jan 2023 Sector 7 7 8 29 44
27 Jan 2023 Sector 7 4 - - 4
All sectors 49 31 58 138