Model suitable and you can diagnostics

We fit our Bayesian state-space model, consisting of both movement and observation process components, using Markov chain Monte Carlo (MCMC) methods. We assigned uninformative priors whenever there were no a priori expectations about the relationships of the model parameters and the movement behavior states (see Appendix S1). _n,t) within each iteration of the MCMC algorithm (see Appendix S2). We initialized six chains from random starting values drawn from the prior distributions. After initial pilot tuning and burn-in, we ran the chains until the univariate Gelman–Rubin potential scale reduction factor (PSRF) for monitored parameters was <1.2 and effective sample sizes exceeded 4000. This required about 6 million iterations per chain, where 1 million iterations for each parallel chain required about 100 h using six cores of a 3.7-GHz processor. Data and code can be found in Data S1.

Performance

Predicated on posterior methods to possess state projects, we discover these types of bearded seals invested 70% of its deployment attacks throughout the benthic foraging county (B). They hauled out on frost (state I) and you will rested at the ocean (state S) inside the roughly equivalent dimensions, however, there was an obvious regular component when you look at the interest finances among the latest hauled out on frost (I), benthic foraging (B), and you may transit (T) states you to coincided for the summer sanctuary and you can wintertime progress out of sea ice about Arctic (Dining table dos). All seals shown extreme benthic foraging over the continental shelves regarding the Chukchi or Beaufort seas once the ocean frost receded northward for the the summertime. We located little or no evidence of these freeze-related seals dragging on house, in the event close to the shore from inside the mainly ice-totally free months in the summertime. Surprisingly, a grown-up male briefly moved north of one’s Beaufort seaside shelf in later and was predicted getting hauled out on new falling out sea freeze border anywhere between bouts of middle-liquids foraging about better oceans of your Canada Basin (Fig. 2). We offer reveal cartoon out of forecast movements and you may condition tasks for everybody seals in line with bathymetry and you can water frost defense when you look at the Appendix S3.

• There are regular variations in hobby costs anywhere between “summer” (regarding marking when you look at the later June and you will very early July so you can 29 September), “autumn” (step 1 Oct in order to 31 December), and you can “winter” (1 January up to tag losses ranging from March and you may April) one coincided to your south advance out-of winter season ocean frost in the the Cold. Craft budget information had been determined according to the posterior form out-of time invested into the for every condition with all the way down (LCI) and upper (UCI) credible times considering 95% higher posterior density. Individual close pastime finances are part of Appendix S4.

As expected, the resting states (I, S, and L) exhibited shorter step lengths, no directional persistence, and lower proportions of each time step diving >4 m below the surface based on state-specific parameter estimates (Fig. 3; see Appendix S4 for posterior sumeters). Both the mid-water foraging (M) and transit (T) states exhibited longer step lengths, lower proportions Asian Sites dating service of dry time, and higher proportions of diving >4 m below the surface. Only the transit state exhibited strong directional persistence, but state M exhibited moderate directional persistence for some individuals (Fig. 3). The benthic foraging (B) state generally exhibited moderate step lengths, no directional persistence, lower proportions of dry time, higher proportions of diving >4 m below the surface, and considerably higher benthic dive counts (posterior median for ?_B = 41.4; 95% highest posterior density interval: 41.2–41.7). The resting (?_I = ?_S = ?_L = 9.7; 95% HPDI: 9.4–10.0) and transit (?_T = 15.0; 95% HPDI: 14.5–15.5) states exhibited moderate benthic dive counts, while the mid-water foraging state generally had the lowest benthic dive counts (?_M = 1.5; 95% HPDI: 1.3–1.7; Fig. 3). The moderate benthic dive counts for the resting and transit states could be attributable to mid-interval state switches, but there certainly could have been opportunistic benthic foraging during transit. There also could have been high-speed, directionally persistent benthic dives while transiting in relatively shallow shelf waters.