为了了解海洋哺乳动物在海上时如何满足它们的日常睡眠要求，研究人员监测了野生北象海豹（Mirounga angustirostris）在加州蒙特利湾潜水时的脑电活动。脑波模式显示，海豹在潜水时进行短暂的（少于20分钟）小睡（最大深度377米；104次睡眠潜水）。
将这些模式与334只自由放养的海豹（514406次睡眠潜水）的加速器和时间深度曲线联系起来，研究人员发现在北太平洋的睡眠环境中，海豹在7个月内平均每天只睡2小时，与目前由非洲象保持的所有哺乳动物中睡眠最少的记录（每天约2小时）相媲美。
据悉，睡眠是哺乳动物日常活动模式的一个重要部分。然而，对于在海上度过数月或终生的海洋物种，睡眠的地点、时间和持续时间可能受到限制。
附：英文原文
Title: Brain activity of diving seals reveals short sleep cycles at depth
Author: Jessica M. Kendall-Bar, Terrie M. Williams, Ritika Mukherji, Daniel A. Lozano, Julie K. Pitman, Rachel R. Holser, Theresa Keates, Roxanne S. Beltran, Patrick W. Robinson, Daniel E. Crocker, Taiki Adachi, Oleg I. Lyamin, Alexei L. Vyssotski, Daniel P. Costa
Issue&Volume: 2023-04-20
Abstract: Sleep is a crucial part of the daily activity patterns of mammals. However, in marine species that spend months or entire lifetimes at sea, the location, timing, and duration of sleep may be constrained. To understand how marine mammals satisfy their daily sleep requirements while at sea, we monitored electroencephalographic activity in wild northern elephant seals (Mirounga angustirostris) diving in Monterey Bay, California. Brain-wave patterns showed that seals took short (less than 20 minutes) naps while diving (maximum depth 377 meters; 104 sleeping dives). Linking these patterns to accelerometry and the time-depth profiles of 334 free-ranging seals (514,406 sleeping dives) revealed a North Pacific sleepscape in which seals averaged only 2 hours of sleep per day for 7 months, rivaling the record for the least sleep among all mammals, which is currently held by the African elephant (about 2 hours per day).
DOI: adf0566
Source: https://www.science.org/doi/10.1126/science.adf0566