Trukhanova Irina S, Grachev Aleksey I, Somov Aleksandr G, Burkanov Vladimir N, Laidre Kristin L, Boveng Peter L
Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, Washington, United States of America.
Marine Mammal Laboratory, Alaska Fisheries Science Center, National Oceanic and Atmospheric Administration, Seattle, Washington, United States of America.
PLoS One. 2017 Aug 10;12(8):e0182725. doi: 10.1371/journal.pone.0182725. eCollection 2017.
Sealing log books from 75 out of 79 commercial harvest cruises carried out between 1972 and 1994 in the Sea of Okhotsk, Russia, were analyzed to describe spatial and temporal allocation of ice-associated seal harvest effort, species composition of catches, total harvest rates, and related parameters for species including ringed (Pusa hispida), ribbon (Histriophoca fasciata), bearded (Erignathus barbatus) and spotted (Phoca largha) seal. Variations in catch per unit effort were explored in relation to year, sea ice conditions, day of the year, and geographic location. In most years, the harvest was predominantly represented by ringed seals (mean = 0.43, range 0.25-0.67), followed by ribbon (mean = 0.31, range 0.15-0.43), spotted (mean = 0.19, range 0.11-0.35) and bearded seals (mean = 0.07, range 0.03-0.14). The struck-and-lost percentages were as high as 30-35% for ringed, bearded and spotted seals and 15-20% for ribbon seals. Catch per unit effort (number of seals/skiff*day) for ringed, ribbon, and spotted seals had a similar seasonal pattern with a distinct spike in catches for spotted seals in the first week of May, for ribbon seals in the last week of May, and for ringed seals in the second week of June. Catches of bearded seals showed a less pronounced temporal structure with a gradual increase toward the end of the harvest season in the majority of years. Spatial distribution of harvest effort followed closely with seal distribution obtained from aerial surveys. These data could be used as a source of information on seal herd location throughout the breeding and molting seasons and for more complex demographic or life-table models. We did not find any evidence of the decline of catch per unit effort over the study period. Timely introduction of state regulations and efficient harvest management apparently prevented severe depletion of ice-associated seal populations in the Sea of Okhotsk during the periods of their intense exploitation.
对1972年至1994年期间在俄罗斯鄂霍次克海进行的79次商业捕捞航行中的75次航行的航海日志进行了分析，以描述与冰相关的海豹捕捞活动的空间和时间分配、渔获物的种类组成、总捕捞率以及包括环斑海豹（Pusa hispida）、带纹海豹（Histriophoca fasciata）、髯海豹（Erignathus barbatus）和斑海豹（Phoca largha）在内的物种的相关参数。探讨了单位捕捞努力量渔获量随年份、海冰条件、一年中的日期和地理位置的变化。在大多数年份，捕捞量主要以环斑海豹为主（平均=0.43，范围0.25 - 0.67），其次是带纹海豹（平均=0.31，范围0.15 - 0.43）、斑海豹（平均=0.19，范围0.11 - 0.35）和髯海豹（平均=0.07，范围0.03 - 0.14）。环斑海豹、髯海豹和斑海豹的击伤后丢失率高达30 - 35%，带纹海豹为15 - 20%。环斑海豹、带纹海豹和斑海豹的单位捕捞努力量渔获量（海豹数量/小艇*天）具有相似的季节性模式，斑海豹在5月的第一周、带纹海豹在5月的最后一周、环斑海豹在6月的第二周捕捞量有明显峰值。髯海豹的捕捞量时间结构不太明显，在大多数年份里，随着捕捞季节接近尾声逐渐增加。捕捞活动的空间分布与通过空中调查获得的海豹分布密切相关。这些数据可作为整个繁殖和换毛季节海豹种群位置信息的来源，用于更复杂的种群统计学或生命表模型。在研究期间，我们没有发现单位捕捞努力量渔获量下降的任何证据。及时引入国家法规和有效的捕捞管理显然防止了鄂霍次克海海豹种群在其被高强度开发期间的严重枯竭。
