Table 1.
Parameter estimates (mean, 95% confidence interval) for state-dependent distributions for female and male Weddell seals, from the respective HMMs—six states for females, five states for males. The proportion state occupancy is calculated as the proportion of observations labelled as each state. Note that there are four dive states for females to spread their activity over compared to three in males. This naturally leads to smaller proportions in the six-state scenario. However, if all states occur equally often, the proportions would all be smaller, which we do not see.
| sex | haulout events | surface events | shallow dives | epipelagic dives | pelagic dives | benthic dives | |
|---|---|---|---|---|---|---|---|
| duration | F | 2.8 h (2.7–3.0) | 37.9 min (36.4–39.5) | 1.0 min (59–64 s) | 7.4 min (7.2–7.7) | 14.1 min (13.9–14.2) | 19.0 min (18.7–19.2) |
| M | 3.5 h (3.3–3.7) | 34.3 min (32.6–35.9) | 2.3 min (2.2–2.4) | 11.0 min (10.7–11.3) | — | 18.2 min (18.1–18.4) | |
| depth (m) | F | — | — | 8.8 (8.6–8.9) | 38.5 (37.2–39.8) | 193.8 (189.0–198.6) | 413.1 (409.9–416.3) |
| M | — | — | 10.2 (10.1–10.4) | 90.0 (86.8–93.2) | — | 411.8 (408.5–415.1) | |
| proportion of dive | F | — | — | 0.51 (0.50–0.51) | 0.55 (0.54–0.56) | 0.49 (0.48–0.50) | 0.43 (0.42–0.44) |
| spent hunting | M | — | — | 0.53 (0.52–0.53) | 0.46 (0.46–0.47) | — | 0.42 (0.41–0.42) |
| proportion of | F | — | — | 0.00 | 0.00 | 0.00 | 0.89 (0.72–1.00) |
| bathymetry reached | M | — | — | 0.00 | 0.00 | — | 0.91 (0.77–1.00) |
| salinity at | F | — | — | 34.18 (34.178–34.192) | 34.29 (34.283–34.292) | 34.44 (34.433–34.444) | 34.61 (34.603–34.608) |
| depth (psu) | M | — | — | 34.23 (34.226–34.234) | 34.36 (34.351–34.360) | — | 34.59 (34.591–34.598) |
| state occupancy | F | 0.13 (0.10–0.17) | 0.21 (0.18–0.28) | 0.17 (0.12–0.23) | 0.24 (0.14–0.36) | 0.15 (0.07–0.30) | 0.09 (0.01–0.26) |
| M | 0.13 (0.10–0.17) | 0.20 (0.12–0.26) | 0.31 (0.09-0.42) | 0.19 (0.12–0.31) | — | 0.17 (0.11–0.36) |