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1.
A unique whale call with 50–52 Hz emphasis from a single source has been tracked over 12 years in the central and eastern North Pacific. These calls, referred to as 52-Hz calls, were monitored and analyzed from acoustic data recorded by hydrophones of the US Navy Sound Surveillance System (SOSUS) and other arrays. The calls were noticed first in 1989, and have been detected and tracked since 1992. No other calls with similar characteristics have been identified in the acoustic data from any hydrophone system in the North Pacific basin. Only one series of these 52-Hz calls has been recorded at a time, with no call overlap, suggesting that a single whale produced the calls. The calls were recorded from August to February with most in December and January. The species producing these calls is unknown. The tracks of the 52-Hz whale were different each year, and varied in length from 708 to 11,062 km with travel speeds ranging from 0.7 to 3.8 km/h. Tracks included (A) meandering over short ranges, (B) predominantly west-to-east movement, and (C) mostly north-to-south travel. These tracks consistently appeared to be unrelated to the presence or movement of other whale species (blue, fin and humpback) monitored year-round with the same hydrophones.  相似文献   
2.
The American whaling industry rose from humble beginnings off Long island to become an international giant. In its peak year, 1846, 735 ships and 70,000 people served the industry. As whale stocks and reserves decreased, whalers were forced to go farther and farther from their New England home ports. Voyages became longer, and risks on required return-on-investment became higher. The easy money of Atlantic and Pacific whaling was no more: the only remaining profitable ventures were to Arctic and Antarctic waters. Many ships returned empty, if at all. in 1871, most of the Arctic whaling fleet was crushed by early winter ice and lost. This calamity, in conjunction with the long-term diminishing whale stocks, the diversion of investment capital to more profitable ventures, and the discovery, development, and refinement of abundant petroleum crude oil, struck the death blow to the American whaling industry. By 1890, only 200 whaling vessels were at work, and by 1971, no American commercial whaling ship sailed the world's oceans.It is apparent that no single event caused the final, rapid decline. However, a single calamity, in an already stressed industry, that was self-insured and commercially interlinked, precipitated the end. Today's American petroleum industry, although adopting some principles of the American whaling industry, also has embraced other activities such as work process reengineering and customer alliances, which may preempt, or postpone, a similar catastrophic demise.  相似文献   
3.
Mexico's Federal Programme of Actions for the Conservation of the Blue Whale (PACE) (Balaenoptera musculus) prioritizes whale watching (WW) research in the Loreto Bay National Park due to the increase of this activity. The aim of this study was to investigate whether whale watchers’ socioeconomic characteristics, motivations, attitudes towards whale conservation, and boat crowding influence the potential demand for WW for both first visits and the willingness to return to Loreto Bay National Park. A total of 143 structured surveys were conducted during the 2014 winter season after WW boats had returned to port. Logit econometric models in STATA were used in this analysis. The results show that the first WW experience is determined significantly by gender, nationality, whether hotel activities are a motivation for travelling, and knowledge about whales. The willingness to return depends on gender, nationality, sun and beach beauty, plans for WW before leaving home, and attitudes towards whale conservation. The results show that the reported crowding of whale mothers and calves and the willingness to accept more boats is negatively related to the willingness to return. Management recommendations are to maintain the current legislation, continue with passive observation and optimize the number of trips and tourists per boat. Differences in the demand determinants and in the type of tourists for first and repeat visitors suggest the possibility of creating different market segments. A national programme for WW that considers WW diversity and conservation initiatives would enhance sustainable wildlife tourism as part of marine policies.  相似文献   
4.
The Japanese government is committed to resuming sustainable commercial whaling, both on the high seas and along the Japanese coastline. To this end scientific whaling programs are supported with public money and the byproducts of the catch are distributed to the public and utilized in a variety of ways. Here we review the policies which govern how these byproducts are disseminated within Japan, as well as how the population as a whole makes use of whale resources. Possibilities for the future, if and when the international moratorium on commercial whaling ends, are also discussed.  相似文献   
5.
Vigtorniella flokati, a new species of polychaete worm associated with decaying whale remains, is described. Three separate V. flokati populations were sampled using submersibles: two associated with implanted gray whale carcasses in the San Diego Trough (1240 m depth) and the Santa Cruz Basin (1670 m) off California, and one from sperm whale and balaeanopterid bones implanted on the slope of Oahu, Hawaii at 1000 m. Extraordinarily large numbers of live specimens were observed and videotaped in situ using submersibles in the San Diego Trough and the Santa Cruz Basin. The populations on the carcass implanted for 4 months in San Diego Trough, and on the bones implanted for 2 years off Oahu, were composed only of small sized individuals (including juveniles). V. flokati most closely resembles the poorly known V. zaikai Kiseleva, 1992, described from the Black Sea. Forty-six morphological characters were used in a phylogenetic analysis of selected nereidiform polychaetes. The resulting most-parsimonious trees indicate sister taxon status between V. flokati and V. zaikai, and that this clade is sister to the putatively ancient polychaete clade Chrysopetalidae. Whale falls, which are intense point sources of organic enrichment at the deep-sea floor, pass through three successional stages. V. flokati appears to colonize the middle, “enrichment opportunist” stage, inhabiting organic-rich bones and sediments 4–24 months after carcass arrival. V. flokati exhibits remarkable behavior, clinging posteriorly to whale bones or nearby sediments to form a writhing carpet at densities exceeding 8000 m−2. Its extraordinary abundance on whale falls, and apparent absence from other habitats, suggests it to be a whale-fall specialist. The precise feeding mechanism of the worm remains unknown, but we hypothesize that it may utilize dissolved organic carbon derived from the organic-rich setting of whale falls. The widespread occurrence of V. flokati on ephemeral, food-rich habitat islands in the Pacific suggests life-history strategies analogous to those for hydrothermal-vent and cold-seep species.  相似文献   
6.
Human–wildlife conflict is one of the major challenges in conservation biology. Here, we investigated the human–wildlife conflicts and their impacts in and around Chebera-Churchura National Park, Ethiopia. We conducted semistructured interview for 300 people and five focus group discussions from November 2010 to January 2011. In addition, scats of 60 spotted hyenas were collected and analyzed. Totally, 12 carnivores, 6 herbivores, and 2 primate species posing a significant problem were identified. Intensive human–wildlife conflict was observed in Churchura, Sere, and Chebera villages which were very close to the park. The carnivore’s attacks during 2007–2011 had caused about 30.49% of livestock losses. The overall economic loss by wildlife attacks was estimated to be US$ 75,234 (US$ 83/household/year). Scat analysis confirmed a substantial contribution (59%) of livestock to spotted hyena’s diet. Thus, combined strategies like improving livestock husbandries and strengthen the capacity of managers are imperative to mitigate the problems.  相似文献   
7.
Levels of total mercury (T-Hg) were surveyed in red meat (n=73) and liver (n=3) from toothed whales, dolphins and porpoises (odontocetes) sold for human consumption in the coastal cities of South Korea. High concentrations of T-Hg were found in the liver products of finless porpoises (18.7 and 156 microg/wet g) and common dolphins (13.2 microg/wet g). The T-Hg concentrations in red meat products were highest in the false killer whale (9.66+/-12.3 microg/wet g, n=9), bottlenose dolphin (10.6+/-12.6 microg/wet g, n=3) and killer whale (13.3 microg/wet g, n=1), and lowest in Cuvier's beaked whale and the harbour porpoise (0.4-0.5 microg/wet g). Thus, most of the products that originated from odontocetes exceeded the safety limit of 0.5 microg/wet g for T-Hg set by the South Korean health authorities for the fishery industry. Pregnant women and other vulnerable sectors of the population living in South Korea should therefore limit their consumption of odontocete products.  相似文献   
8.
Whale watching is now reputed to be a $2 billion a year industry. This industry has the potential to impact the politics of whaling, specifically the moratorium on all commercial whaling in three ways: by creating political and economic counterweights to whalers, by countering claims about who may legitimately manage whales and to what end and by transforming views about whales and whaling both within whaling states and beyond. This article examines whale watching in Latin America and the Caribbean and the alliance of Latin American and Caribbean members of the International Whaling Commission (IWC) known as the Buenos Aires Group (BAG). The BAG group has emerged as coherent group opposing the ending of the moratorium and championing the views of whale watchers. The article finds that whale watching creates a politically important interest group in an area lacking whaling operations; it argues that these regional opponents of whaling provide a counter weight to charges that opposition to whaling is exclusively the providence of rich, urban citizens of developed countries and draw upon politically powerful frames in justifying their opposition to the lifting of the moratorium. Finally, it finds limited evidence that whale-watching is associated with a rise in general concern for marine mammals in the region. There remains the question, however, of what the future of whale watching in the region will be over the longer term.  相似文献   
9.
Whale depredation occurs when whales steal fish, damage fish or damage fishing gear. In Alaska, killer whales (Orcinus orca) and sperm whales (Physeter macrocephalus) primarily depredate on demersal sablefish (Anoplopoma fimbria) and Pacific halibut (Hippoglossus stenolepis) longline fisheries. Quantitative data on whale depredation in Alaska is limited due to low fishery observer coverage and minimal depredation evidence left on longline fishing gear. This study utilized semidirected interviews (n=70) and written questionnaires (n=95) with longline fishermen to examine: (1) perceptions and experiences of whale–fishery interactions in Alaska, (2) effects of depredation on fishing practices, and (3) potential depredation mitigation measures. Eighty-seven percent of fishermen surveyed agreed that whale depredation became worse between 1990 and 2010. Respondents reported changing their fishing practices in response to depredating whales in several ways, including: traveling up to 50 nautical miles and ceasing hauling operations up to 24 h until the whales left the fishing grounds. Respondents fishing in western Alaska, primarily encountering killer whales, were forced to wait longer and travel greater distances than fishermen operating in central and southeast Alaska, regions more affected by sperm whales. Deterrent research, gear modifications and real-time tracking of depredating whales were solutions favored by study participants. Survey respondent answers varied based on areas fished, quota owned, years involved in the fishery and vessel size. This study presents the first statewide evaluation of fishermen's perception and knowledge of whale interactions with the Alaskan longline fleet and is a critical step toward developing baseline data and feasible depredation mitigation strategies.  相似文献   
10.
The degradation and preservation affecting the biomarker record of ancient metazoa are not fully understood. We report on a five month experiment on the fate of fatty acids (FAs) during the degradation of recent whale vertebrae (Phocoena phocoena). Whale bones were analysed for extractable FAs and macromolecularly bound n-acyl compounds. Fresh bone showed extractable FAs dominated by 16:1ω7c, 16:0, 18:1ω9c and 18:0. Calculated degradation rate constant (k) values showed a rapid decrease in FA concentration, with k values higher for unsaturated than for saturated compounds (0.08/day for 18:1ω9c, 0.05/day for 16:0). The appearance or increased abundance of distinctive methyl branched (e.g. i/ai-15:0 and -17:0, 10Me-16:0) and hydroxy FAs (e.g. 10OH-16:0 and 10OH-18:0) were observed, providing clear evidence for the microbial degradation of bone organic matter and an input of lipids from specialised bacteria. Catalytic hydropyrolysis (HyPy) of demineralised extraction residues released up to 0.13% of the total n-C16 and n-C18 moieties in the degraded bones. This revealed that only a small, yet sizeable, portion of bone-derived fatty acyl units was sequestered into (proto)kerogen during the earliest stages of degradation.  相似文献   
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