New Zealand fur seal demographics

Open Bay Islands, 2020

Mark-recapture estimate, 31 Jan – 01 Feb 2020

Total marked
384
Mean estimate
989.0
Range
812.5 – 1125.3

Mark-recapture counts

Count number Date Time Sector Unmarked count Marked count Dead marked Dead unmarked Total marked Cum. dead Estimate?
1 31 Jan 2020 09:30 – 09:35 Sector 1 2 -
31 Jan 2020 09:35 – 09:45 Sector 2 19 16
31 Jan 2020 09:50 – 10:00 Sector 3 34 28
31 Jan 2020 10:05 – 10:20 Sector 4a 15 15
31 Jan 2020 10:20 – 10:43 Sector 4b 6 34
31 Jan 2020 10:45 – 11:05 Sector 5 43 28
31 Jan 2020 11:10 – 11:19 Sector 6a 11 9
31 Jan 2020 11:35 – 11:45 Sector 6b 20 18
31 Jan 2020 11:50 – 11:53 Sector 6c - 3
31 Jan 2020 12:15 – 12:18 Sector 7a 7 3
31 Jan 2020 12:18 – 12:25 Sector 7b 18 9
31 Jan 2020 12:25 – 12:35 Sector 7c 12 4
All sectors 187 167 - - 384 - 812.5
2 31 Jan 2020 16:42 – 16:45 Sector 1 1 -
31 Jan 2020 16:30 – 16:40 Sector 2 12 7
31 Jan 2020 16:04 – 16:23 Sector 3 28 12
31 Jan 2020 15:35 – 16:00 Sector 4 37 23
31 Jan 2020 15:10 – 15:34 Sector 5 22 14
31 Jan 2020 14:46 – 14:53 Sector 6a 4 5
31 Jan 2020 14:18 – 14:40 Sector 6b 24 22
31 Jan 2020 14:13 – 14:18 Sector 6c - 2
31 Jan 2020 12:45 – 12:48 Sector 7a 9 5
31 Jan 2020 12:48 – 12:55 Sector 7b 14 9
31 Jan 2020 12:55 – 13:04 Sector 7c 10 6
All sectors 161 105 - - 384 - 968.8
3 31 Jan 2020 17:25 – 17:28 Sector 1 1 -
31 Jan 2020 17:29 – 17:40 Sector 2 11 6
31 Jan 2020 17:44 – 17:56 Sector 3 15 17
31 Jan 2020 18:01 – 18:12 Sector 4a 21 6
31 Jan 2020 18:13 – 18:24 Sector 4b 22 18
31 Jan 2020 18:25 – 18:46 Sector 5 13 9
31 Jan 2020 18:53 – 19:01 Sector 6a 5 2
31 Jan 2020 19:05 – 19:19 Sector 6b 14 5
31 Jan 2020 19:20 – 19:26 Sector 6c - 2
31 Jan 2020 13:10 – 13:15 Sector 7a 7 6
31 Jan 2020 13:30 – 13:37 Sector 7b 9 8
31 Jan 2020 13:37 – 13:47 Sector 7c 15 3
All sectors 133 82 - - 384 - 1000.9
4 01 Feb 2020 06:49 – 06:51 Sector 1 1 -
01 Feb 2020 06:51 – 07:00 Sector 2 19 16
01 Feb 2020 07:04 – 07:14 Sector 3 23 14
01 Feb 2020 07:17 – 07:30 Sector 4a 18 8
01 Feb 2020 07:32 – 07:48 Sector 4b 29 8
01 Feb 2020 07:50 – 08:06 Sector 5 28 15
01 Feb 2020 08:06 – 08:14 Sector 6a 12 6
01 Feb 2020 08:14 – 08:25 Sector 6b 18 8
01 Feb 2020 08:25 – 08:35 Sector 6c 2 1
31 Jan 2020 19:58 – 19:59 Sector 7a 7 2
31 Jan 2020 19:53 – 19:58 Sector 7b 20 11
31 Jan 2020 19:59 – 20:03 Sector 7c 4 4
All sectors 181 93 - - 384 - 1125.3
5 01 Feb 2020 08:47 – 08:48 Sector 1 1 -
01 Feb 2020 08:48 – 08:57 Sector 2 10 10
01 Feb 2020 09:00 – 09:11 Sector 3 22 12
01 Feb 2020 09:15 – 09:21 Sector 4a 8 7
01 Feb 2020 09:21 – 09:31 Sector 4b 15 6
01 Feb 2020 09:31 – 09:45 Sector 5 30 12
01 Feb 2020 09:45 – 09:51 Sector 6a 8 3
01 Feb 2020 09:51 – 09:58 Sector 6b 14 14
01 Feb 2020 09:58 – 10:02 Sector 6c - 3
31 Jan 2020 20:44 – 20:47 Sector 7a 10 4
31 Jan 2020 20:32 – 20:38 Sector 7b 23 9
31 Jan 2020 20:38 – 20:44 Sector 7c 10 8
All sectors 151 88 - - 384 - 1037.2

Dead count, 27–30 Jan 2020

Count
97

Dead counts

Date Sector Fresh Decomposing Dry Count
27 Jan 2020 Sector 2 4 3 5 12
28 Jan 2020 Sector 3 2 6 6 14
28 Jan 2020 Sector 4a - 5 3 8
29 Jan 2020 Sector 4b 1 3 3 7
29 Jan 2020 Sector 5 3 5 3 11
30 Jan 2020 Sector 6 4 10 4 18
30 Jan 2020 Sector 7 5 6 16 27
All sectors 19 38 40 97